Resist composition, method for producing resist pattern, compound, and resin

Abstract

To provide a resist composition, a resin and the like which allow a resist pattern having good CD uniformity to be produced.SOLUTION: The resin contains a structural unit of formula (I) and a structural unit represented by formula (a1-4) and / or formula (a1-6).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resist composition, a method for producing a resist pattern using the resist composition, and a compound and a resin.

Background Art

[0002] Patent Document 1 describes a resist composition containing a resin including the following structural unit. TIFF2025100428000001.tif27100

[0003] Patent Document 2 describes a resin including the following structural unit. TIFF2025100428000002.tif27100

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides a resist composition that forms a resist pattern having better CD uniformity (CDU) than a resist pattern formed by the above resist composition.

[0006] The present invention includes the following inventions. [1] A resist composition containing a resin including a structural unit represented by formula (I) and at least one selected from the group consisting of a structural unit represented by formula (a1-4) and a structural unit represented by formula (a1-6). TIFF2025100428000003.tif4370[In formula (I), R R1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 11 represents a single bond or *-Ar-O-CO-. * represents the bonding site with the carbon atom to which R 1 is bonded. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R c1 , R c2 and R c3 each independently represent a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 48 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. TIFF2025100428000004.tif31118[In formula (a1-4), R a1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a17 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a11 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO- or -NR a18 -. R a18 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a1 represents a single bond or a carbonyl group. R a34 and R a35 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or Ra35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. na1 represents any integer from 1 to 5, and when na1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na11 represents any integer from 0 to 4, and when na11 is 2 or more, the plurality of R a17 may be the same as or different from each other. mc represents any integer from 0 to 2.] TIFF2025100428000005.tif3479[In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a62 R a63 and R a64 each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a62 and R a63 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. X a61 represents a single bond, -CO-O-*, or -CO-NR a65 -*, where * represents the bonding site to Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 -, or *-CO-O-L a62 -, where * represents the bonding site to Ar, and L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.] The resist composition according to [1], which contains only one of the structural units (a1-4) and the structural unit (a1-6). [3]A a11 and X a61 are a single bond, is the resist composition according to [1] or [2]. [4] The resist composition according to any one of [1] to [3], wherein the resin further contains a structural unit represented by the formula (a2-A). TIFF2025100428000006.tif30128 [In the formula (a2-A), R a2 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO-, or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a2 represents a single bond or a carbonyl group. nA2 represents any integer from 1 to 5, and when nA2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na21 represents any integer from 0 to 4, and when na21 is 2 or more, the plurality of R a27 may be the same as or different from each other. mc represents any integer from 0 to 2.] [5] The resist composition according to any one of [1] to [4], wherein the resin further contains a structural unit represented by the formula (a2-D). TIFF2025100428000007.tif51106[In formula (a2-D), R a2 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO-, or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R a21 and R a22 each independently represent a fluorinated alkyl group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents any integer from 1 to 4. When nD2 is 2 or more, the plural parentheses may be the same as or different from each other. nD22 represents any integer from 0 to 4. When nD22 is 2 or more, the plural R a27 may be the same as or different from each other.] [6] The resist composition according to any one of [1] to [5], wherein the resin further contains a structural unit represented by formula (a7-A). TIFF2025100428000008.tif26124[In formula (a7-A), R a7 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a71is a single bond, *-O-, *-CO-O-, *-O-CO-O-**, *-CO-NR a71 -**, *-NR a71 -CO-O-**, *-O-CO-NR a71 -** or *-Ax-Ph-Ay-**. R a71 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent bonding sites, and * represents the bonding site with the carbon atom to which R a7 is bonded. L a71 and L a72 each independently represent a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. X a72 represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, and *** represents the bonding site with L a71 na7 represents an integer of 0 to 2, and when na7 is 2 or more, the groups in a plurality of parentheses may be the same as or different from each other. RA - represents a sulfonate anion or a carboxylate anion. ZA + represents an organic cation.] [7] The resist composition according to any one of [1] to [6], further comprising an acid generator, wherein the acid generator is a salt represented by the formula (B1). TIFF2025100428000009.tif1591 [In the formula (B1), L b1 represents a single bond or an (nb1 + 1)-valent hydrocarbon group which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.​ L b2 represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. nb1 represents an integer of any one of 1 to 6. When nb1 is 2 or more, the groups in a plurality of parentheses may be the same as or different from each other. Z1 + represents an organic cation. [8] The resist composition according to [7], further containing a salt that generates an acid having a lower acidity than the acid generated from the acid generator. [9] (1) A step of applying the resist composition according to any one of [1] to [8] onto a substrate, (2) A step of drying the applied resist composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, which is a method for manufacturing a resist pattern.

[10] A resin containing the structural unit represented by the above-described formula (I) and at least one selected from the group consisting of the structural unit represented by the above-described formula (a1-4) and the structural unit represented by the above-described formula (a1-6).

[11] The resin according to

[10] , containing only one of the structural units represented by the formula (a1-4) and the formula (a1-6).

[12] A a11 and X a61 are a single bond, which is the resin according to

[10] or

[11] .

[13] The resin according to any one of

[10] to

[12] , further comprising at least one selected from the group consisting of the structural unit represented by formula (a2-A), the structural unit represented by formula (a2-D), and the structural unit represented by formula (a7-A).

[14] A resin containing a structural unit represented by formula (IA). TIFF2025100428000010.tif6173 [In formula (IA), all symbols have the same meanings as described above, respectively.]

[15] A compound represented by formula (IA-s). TIFF2025100428000011.tif6172 [In formula (IA-s), all symbols have the same meanings as described above, respectively.] [Advantages of the Invention]

[0007] By using the resist composition of the present invention, a resist pattern can be produced with good CD uniformity (CDU). [Modes for Carrying Out the Invention]

[0008] As used herein, the term “(meth)acrylic monomer” means at least one member selected from acrylic monomers and methacrylic monomers. The notations such as “(meth)acrylate” and “(meth)acrylic acid” also represent the same meaning. Among the groups described in this specification, those that can take both a linear structure and a branched structure may be either of them. When -CH2- contained in a hydrocarbon group or the like is replaced by -O-, -S-, -CO- or -SO2-, the same examples are applied to each group, and the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group or the like. The term “combined group” means a group formed by combining two or more of the exemplified groups by appropriately changing their valences, bonding forms and the like. The terms “derived from” or “derived” refer to the fact that the polymerizable C═C bond contained in the molecule becomes a single bond (-C-C-) by polymerization. When stereoisomers exist, all stereoisomers are included. The term “acid-labile group” means a group having a leaving group, and when contacted with an acid (for example, trifluoromethanesulfonic acid or the like), the leaving group is eliminated to form a hydrophilic group (for example, a hydroxy group or a carboxy group). As will be described later, the base-labile group means a group that forms a carboxy group or a hydroxy group when contacted with a base (for example, trimethylamine, tetramethylammonium hydroxide or the like). As used herein, the term “solid content of the resist composition” means the total of the components excluding the solvent (E) described later from the total amount of the resist composition.

[0009] [Resin] The resin of the present invention is a resin (hereinafter sometimes referred to as “resin (A)”) containing a structural unit represented by the formula (I) (hereinafter sometimes referred to as “structural unit (I)”) and at least one selected from the group consisting of a structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as “structural unit (a1-4)”) and a structural unit represented by the formula (a1-6) (hereinafter sometimes referred to as “structural unit (a1-6)”). Resin (A) may contain structural units known in the art other than structural unit (I), structural unit (a1-4) and structural unit (a1-6).

[0010] <Structural unit (I)> The structural unit (I) is a structural unit represented by the following formula (I), and is derived from, for example, a compound represented by the following formula (I-s) (hereinafter sometimes referred to as compound (I-s)), and the CH2=C-R 1 in the compound (I-s) is in a state where the double bond is cleaved. TIFF2025100428000012.tif4991[In formula (I) and formula (I-s), all symbols have the same meanings as described above.]

[0011] R 1 Examples of the alkyl group having 1 to 6 carbon atoms in R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R 1 Examples of the halogen atom in R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 1 Examples of the alkyl group having 1 to 6 carbon atoms and having a halogen atom in R include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, and a dibromomethyl group. R 1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0012] X 11Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms in Ar include a phenylene group, o-methylphenylene group, m-methylphenylene group, p-methylphenylene group, p-ethylphenylene group, p-tert-butylphenylene group, 1-naphthylene group, 2-naphthylene group, 1-anthrylene group, 9-anthrylene group, 1-phenanthrylene group, and 2-phenanthrylene group. Examples of the substituent that the aromatic hydrocarbon group of Ar may have include a halogen atom, hydroxy group, alkyl group having 1 to 6 carbon atoms, haloalkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 12 carbon atoms, alkoxyalkoxy group having 2 to 12 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyloxy group having 2 to 4 carbon atoms, acryloyloxy group, or methacryloyloxy group. Examples of the halogen atom, alkyl, and haloalkyl group include the same groups as the halogen atom of R 1 and the alkyl group that may have a halogen atom.

[0013] Examples of the alkoxy group include a methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, and hexyloxy group. The alkoxy group preferably has 1 to 4 carbon atoms, more preferably a methoxy group or ethoxy group, and even more preferably a methoxy group. Examples of the alkoxyalkyl group include a methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and tert-butoxymethyl group. The alkoxyalkyl group preferably has 2 to 8 carbon atoms, more preferably a methoxymethyl group or ethoxyethyl group, and even more preferably a methoxymethyl group. Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Examples of the substituent include a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms. More preferably, the substituent is a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group. Even more preferably, the substituent is a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, more preferably a phenylene group which may have a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms.

[0014] In structural unit (I), X 11 When the structural unit in which is *-Ar-O-CO- is referred to as structural unit (IA), structural unit (IA) is derived from a compound represented by the following formula (IA-s) (hereinafter sometimes referred to as compound (IA-s)), and the double bond of CH2=C-R contained in compound (IA-s) 1 is in a cleaved state. TIFF2025100428000013.tif5379[In formula (IA) and formula (IA-s), all the symbols have the same meanings as described above respectively.]

[0015] Examples of the structural unit (I) include the following structural units and the like. TIFF2025100428000014.tif126160

[0016] In the above structural unit, a hydrogen atom corresponding to R 1 which is replaced by a methyl group, a halogen atom, a haloalkyl group or an alkyl group other than a methyl group can also be cited as a specific example of the structural unit (I). Among them, the structural unit (I) is preferably a structural unit (I-1) to a structural unit (I-6). The compound (I-s) can be produced according to the production method disclosed in JP-A-2009-031767.

[0017] <Production method of compound (IA-s)> The compound (IA-s) can be produced, for example, by reacting a compound represented by formula (I-a) and a compound represented by formula (I-b) in a solvent. TIFF2025100428000015.tif45126(In the formula, all the symbols have the same meanings as described above respectively.) Examples of the solvent in this reaction include chloroform, acetonitrile, dimethylformamide and the like. The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 hour to 24 hours.

[0018] Examples of the compound represented by formula (I-a) include compounds represented below, and can also be easily produced by a known production method. TIFF2025100428000016.tif60159Examples of the compound represented by formula (I-b) include carbonyldiimidazole and the like, and can be easily obtained on the market.

[0019] When the resin (A) contains the structural unit (I), the structural unit (I) may be contained alone or may contain two or more kinds. The total content rate of the structural unit (I) is preferably 10 to 95 mol%, more preferably 0.1 mol% to 20 mol%, still more preferably 0.1 to 15 mol%, and even more preferably 1 to 10 mol% with respect to the total of all the structural units of the resin (A).

[0020] 〈Structural unit (a1-4)〉 The structural unit (a1-4) is a structural unit represented by the following formula (a1-4), and is derived from, for example, a compound represented by the following formula (a1-4-s) (hereinafter sometimes referred to as compound (a1-4-s)), and the double bond of CH2=C-R contained in the compound (a1-4) is in a cleaved state. a1 is in a state where the double bond has cleaved. TIFF2025100428000017.tif64122[In formula (a1-4) and formula (a1-4-s), all symbols have the same meanings as described above.]

[0021] R a1 and R a17 Examples of the halogen atom in R and R include a fluorine atom, a chlorine atom, and a bromine atom. R a1 and R a17 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R and R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, still more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a17 Examples of the alkoxy group in R include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably an alkoxy group having 1 to 3 carbon atoms, even more preferably a methoxy group or an ethoxy group, and most preferably a methoxy group. R a17 Examples of the alkoxyalkyl group in R include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably an alkoxyalkyl group having 2 to 4 carbon atoms, even more preferably a methoxymethyl group or an ethoxyethyl group, and most preferably a methoxymethyl group. R a17 Examples of the alkoxyalkoxy group in R include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably an alkoxyalkoxy group having 2 to 4 carbon atoms, even more preferably a methoxyethoxy group or an ethoxyethoxy group. R a17 Examples of the alkylcarbonyl group in R include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a17Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a17 is preferably a halogen atom, a hydroxy group, a carboxy group, an optionally halogenated alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0022] A a11 Examples of the alkanediyl group of A include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, and a dodecane-1,12-diyl group, and branched alkanediyl groups such as a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, a 2-methylbutane-1,4-diyl group, a heptane-1,6-diyl group, an octane-1,7-diyl group, a nonane-1,8-diyl group, a decane-1,9-diyl group, and an undecane-1,10-diyl group. The number of carbon atoms of the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, still more preferably 1 to 4, yet more preferably 1 to 3, and even more preferably 1 or 2. R a18 Examples of the alkyl group of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group. A a11When the -CH2- contained in the alkanediyl group is replaced by -O-, -CO- or -NR a18 , the number of carbon atoms before replacement shall be taken as the number of carbon atoms of the hydrocarbon group. A a11 Examples of groups in which the -CH2- contained in the alkanediyl group of A is replaced by -O- or -CO- include a hydroxy group (a group in which the -CH2- contained in the methyl group is replaced by -O-), a carboxy group (a group in which the -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a carbonyl group (a group in which the -CH2- contained in the methylene group is replaced by -CO-), an oxy group (a group in which the -CH2- contained in the methylene group is replaced by -O-), an amino group (a group in which the -CH2- contained in the alkanediyl group is replaced by -NR a28 -), an alkoxy group (a group in which any -CH2- contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which any -CH2-CH2- contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which any -CH2- contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which any -CH2-CH2- contained in the alkyl group is replaced by -CO-O-), an alkoxycarbonyloxy group (a group in which any -CH2-CH2-CH2- contained in the alkyl group is replaced by -OCO-O-), an alkylamino group (a group in which the -CH2- contained in the alkyl group is replaced by -NR a18 -), a peptide group (a group in which the -CH2-CH2- contained in the ethylene group is replaced by -CO-NR a18-replaced group), an alkanediyl-oxy group (a group in which any -CH2- in the alkanediyl group is replaced by -O-), an alkanediyl-oxycarbonyl group (a group in which any -CH2-CH2- in the alkanediyl group is replaced by -O-CO-), an alkanediyl-carbonyl group (a group in which any -CH2- in the alkanediyl group is replaced by -CO-), an alkanediyl-carbonyl-oxy group (a group in which any -CH2-CH2- in the alkanediyl group is replaced by -CO-O-), an alkanediyl-sulfonyl group (a group in which any -CH2- in the alkanediyl group is replaced by -SO2-), an alkanediyl-thio group (a group in which any -CH2- in the alkanediyl group is replaced by -S-), an alkanediyl-amino group (a group in which any -CH2- in the alkanediyl group is replaced by -NR a18 -replaced group), etc. These replaced groups include those similar to those exemplified in this specification. Examples of the alkyl-carbonyl-oxy group include alkyl-carbonyl-oxy groups having 2 to 11 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. Examples of the alkoxy-carbonyl-oxy group include alkoxy-carbonyl-oxy groups having 2 to 10 carbon atoms, such as a butoxy-carbonyl-oxy group. The number of carbon atoms of the alkyl-carbonyl-oxy group and the alkoxy-carbonyl-oxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3, respectively. Examples of the alkyl-amino group include alkyl-amino groups having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, and an octylamino group. Examples of the alkanediylamino group include alkanediylthio groups having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, and a propyleneamino group. The number of carbon atoms in the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. For example, A a11 in the alkanediyl group where -CH2- is replaced by -O-, -CO-, or -NR a18 Examples of the group thus replaced include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a12 -CO-O-, *-O-CO-A a12 -O-, *-O-A a12 -CO-O-, *-CO-O-A a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 - Among them, *-CO-O-, *-CO-O-A a12 -CO-O- or *-O-A a12 -CO-O-, *-CO-NR a18 - are preferred. Here, A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site to the carbon atom to which R a1 is bonded. The alkanediyl group of A a12 may be the same alkanediyl group as A a11 within the range allowed by the upper limit of the number of carbon atoms. A a11 is preferably a single bond, *-CO-O-, or *-CO-O-A a12 -CO-O-, more preferably a single bond, *-CO-O-, or *-CO-O-CH2-CO-O-, and still more preferably a single bond or *-CO-O-. na1 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, and still more preferably 1 or 2. na11 is preferably 0, 1, 2, or 3, more preferably 0, 1, or 2, and still more preferably 0 or 1. mc is preferably 0 or 1.

[0023] Ra34 , R a35 and R a36 Examples of the hydrocarbon group in R, R, and R include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and the like. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bonding site). TIFF2025100428000018.tif10151Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (for example, an alkylcycloalkyl group or a cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, and a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as a phenylcyclohexyl group, and the like. In particular, for R a36 , examples include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these. R a35 and R a36The divalent hydrocarbon group having 2 to 20 carbon atoms formed by combining with each other and forming together with -C-O- to which they are bonded includes, for example, the following groups. * represents a bonding site, and one side is R a34 is the bonding site with TIFF2025100428000019.tif15105

[0024] R a34 is preferably a hydrogen atom. R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a36 The hydrocarbon group of is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms. R a36 The alkyl group and alicyclic hydrocarbon group in are preferably unsubstituted. R a36 The aromatic hydrocarbon group in preferably has an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0025] -OC(R a34 )(R a35 )-O-R a36 in the structural unit (a1-4) is eliminated by contact with an acid (for example, p-toluenesulfonic acid) to form a hydroxy group or a carboxy group. -X a1 -OC(R a34 )(R a35 )-O-R a36 In the case of a benzene ring, it may be bonded to any of the o-position, m-position or p-position with respect to the bonding position of A a11 . Among them, at least one is preferably bonded to the o-position or p-position, and more preferably bonded to the p-position. In the case of a naphthalene ring, when the bonding position of A a11 is at the 1-position, it may be bonded to any of the 2nd to 8th positions, and A a11When the bonding position is the 2nd position, it may bond to any of the 1st position and the 3rd to 8th positions. Among them, A a11 When the bonding position of A is the 1st position, at least one preferably bonds to the 3rd to 6th positions, and more preferably bonds to the 3rd or 4th position. A a11 When the bonding position of A is the 2nd position, it preferably bonds to the 4th to 7th positions, and more preferably bonds to the 5th or 6th position.

[0026] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferably, the structural units represented by the formulas (a1-4-1) to (a1-4-42) and the hydrogen atom corresponding to R in the structural unit (a1-4) are replaced with a halogen atom, a haloalkyl group or an alkyl group. More preferably, the structural units represented by the formulas (a1-4-1) to (a1-4-5), the formula (a1-4-10), the formula (a1-4-13), and the formula (a1-4-14) are included. a1 Examples of the structural unit in which the hydrogen atom corresponding to R in the structural unit (a1-4) is replaced with a halogen atom, a haloalkyl group or an alkyl group include structural units represented by the formulas (a1-4-1) to (a1-4-5), the formula (a1-4-10), the formula (a1-4-13), and the formula (a1-4-14). TIFF2025100428000020.tif228165

[0027] When the resin (A) contains the structural unit (a1-4), the structural unit (a1-4) may be contained alone or in two or more kinds. When the resin (A) contains the structural unit (a1-4), the total content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, still more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol% based on the total of all the structural units of the resin (A).

[0028] 〈Structural unit (a1-6)〉 The structural unit (a1-6) is a structural unit represented by the following formula (a1-6), and is derived from, for example, a compound represented by the following formula (a1-6-s) (hereinafter sometimes referred to as compound (a1-6-s)), and the double bond of CH2=C-R contained in the compound (a1-6) is in a cleaved state. a1 is in a state where the double bond is cleaved. TIFF2025100428000021.tif44138 [In formula (a1-6) and formula (a1-6-s), all symbols have the same meanings as defined above.]

[0029] R a61 Examples of the halogen atom in include a fluorine atom, a chlorine atom, and a bromine atom. Of these, a fluorine atom is preferred. R a61 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, and a perfluorohexyl group. R a61 is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group. R a62 , R a63 , R a64 and R a65 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group or an ethyl group. R a62 , R a63 and R a64 The cyclic hydrocarbon group in the formula (I) includes an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group, and the like. Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. R a62 and R a63 Examples of the ring formed by bonding with each other include an adamantane ring, a cyclopentane ring, a cyclohexane ring, and the like. Specifically, when R a62 and R a63 bond with each other to form a ring, examples of -C(R a62 )(R a63 )(R a64 ) include the following groups. * represents the bonding site with an oxygen atom. The number of carbon atoms of the ring is preferably 3 to 16, more preferably 3 to 12. TIFF2025100428000022.tif32110

[0030] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in L L a61 and L a62is preferably a methylene group or an ethylene group, independently of each other. X a61 is preferably a single bond or -CO-O-*, more preferably a single bond. X a62 is preferably a single bond or *-O-L a61 -, more preferably a single bond.

[0031] Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms in Ar include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, and a phenanthrylene group. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group.

[0032] Examples of the halogen atom include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. The substituent is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, and more preferably a phenylene group which may have a hydroxy group.

[0033] Examples of the structural unit (a1-6) include structural units represented by Formula (a1-6-1) to Formula (a1-6-44), etc. Structural units represented by Formula (a1-6-1) to Formula (a1-6-9) are preferred, and structural units represented by Formula (a1-6-1), Formula (a1-6-2), Formula (a1-6-4), Formula (a1-6-5), Formula (a1-6-7) or Formula (a1-6-8) are more preferred, and structural units represented by Formula (a1-6-1) or Formula (a1-6-2) are even more preferred. In the following structural units, R a61 Structural units in which the hydrogen atom corresponding to is replaced by a methyl group or the like, and structural units in the following structural units in which the methyl group corresponding to R a61 is replaced by a hydrogen atom or the like are also included as the structural unit (a1-6). TIFF2025100428000023.tif151164

[0034] When the resin (A) contains the structural unit (a1-6), its content is 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, even more preferably 10 mol% or more, still more preferably 20 mol% or more, still even more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on all the structural units of the resin (A). Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 65 mol%.

[0035] The resin (A) may contain any one of the structural unit (I), the structural unit (a1-4) and the structural unit (a1-6), and preferably further contains structural units other than the structural unit (a1-4) and the structural unit (a1-6). Among them, the resin (A) preferably further contains at least one selected from the group consisting of a structural unit (a2-A), a structural unit (a2-D), and a structural unit (a7-A). The resin (A) may further contain a structural unit other than the structural unit (I), the structural unit (a1-4), the structural unit (a1-6), the structural unit (a2-A), the structural unit (a2-D), and the structural unit (a7-A). The resin (A) may contain a structural unit having an acid-labile group other than the structural unit (a1-4) and the structural unit (a1-6) (hereinafter sometimes referred to as "structural unit (a1)"). The resin (A) may further contain a structural unit other than the structural unit (a1). Examples of the structural unit other than the structural unit (a1) include a structural unit having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)") and a structural unit derived from other monomers known in the art.

[0036] 〈Structural unit (a1)〉 The structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid-labile group contained in the resin (A) or the like is preferably a group represented by the formula (1) (hereinafter also referred to as "group (1)") and / or a group represented by the formula (2) (hereinafter also referred to as "group (2)"). TIFF2025100428000025.tif2298[In the formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, or R a1 and R a2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bonding site.] TIFF2025100428000026.tif2278[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’ are bonded to each other to form a heterocyclic group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X. The -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.]

[0037] R a1 , R a2 and R a3 Examples of the alkyl group in R include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and the like. a1 Examples of the alkenyl group in R a2 include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, a nonenyl group. a3 Examples of the alkenyl group in R include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, a nonenyl group. a1 Examples of the alicyclic hydrocarbon group in R a2 include both monocyclic and polycyclic groups. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bonding site). The alicyclic hydrocarbon group of R a3 preferably has 3 to 16 carbon atoms. a1 Examples of the alicyclic hydrocarbon group in R a2 include both monocyclic and polycyclic groups. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bonding site). The alicyclic hydrocarbon group of R a3 preferably has 3 to 16 carbon atoms. TIFF2025100428000027.tif10159R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group in a1 , a2 and a3 include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like. Examples of the combined group include a group formed by combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), aralkyl group such as benzyl group, aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), aryl-cycloalkyl group such as phenylcyclohexyl group and the like. Preferably, ma is 0 and na is 1. R a1 and R a2 When a1 and a2 are bonded to each other to form an alicyclic hydrocarbon group, examples of -C(R a1 )(R a2 )(R a3 ) include the following groups. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents a bond to -O-. TIFF2025100428000028.tif28137

[0038] R a1’ , R a2’ and R a3’ Examples of the hydrocarbon group in a1’ , a2’ and a3’ include alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group formed by combining these. The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group formed by combining these are R a1 , R a2and R a3 Those similar to the groups exemplified by a3 are exemplified. R a2’ and R a3’ When R and R are bonded to each other to form a heterocyclic ring together with the carbon atom to which they are bonded and X, -C(R a1’ )(R a2’ )-X-R a3’ includes the following rings. * represents the bonding site. TIFF2025100428000029.tif19124R a1’ and R a2’ Among them, at least one of them is preferably a hydrogen atom. na’ is preferably 0. R a1 R a2 R a3 R a1 R a2’ and R a3’ The halogen atom that R, R, R, R, R, R, and R may have includes a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0039] Examples of the group (1) include the following groups. In formula (1), R a1 R a2 and R a3 are alkyl groups, ma = 0, and na = 1. The tert-butoxycarbonyl group is preferred as such a group. In formula (1), R a1 R a2 together with the carbon atom to which they are bonded form an adamantyl group, and R a3 is an alkyl group, ma = 0, and na = 1. In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1. Specific examples of the group (1) include the following groups. * represents a bond. TIFF2025100428000030.tif151162

[0040] Specific examples of the group (2) include the following groups. * represents a bonding site. TIFF2025100428000031.tif55153

[0041] The monomer (a1) is preferably a monomer having an acid-labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid-labile group. Among the (meth)acrylic monomers having an acid-labile group, those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms are preferably mentioned. If a resin (A) or the like having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0042] As the structural unit derived from the (meth)acrylic monomer having the group (1), there are mentioned a structural unit represented by the formula (a1-0) (hereinafter sometimes referred to as the structural unit (a1-0)), a structural unit represented by the formula (a1-1) (hereinafter sometimes referred to as the structural unit (a1-1)), or a structural unit represented by the formula (a1-2) (hereinafter sometimes referred to as the structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2), more preferably at least one or two structural units selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2025100428000032.tif43144[In the formula (a1-0), the formula (a1-1), and the formula (a1-2), L a01 、L a1 and L a2 each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents an integer of 1 to 7, and * represents the bonding site to -CO-. R a01 、R a4 and R a5Each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 、R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. m1’ represents any integer from 0 to 14. n1 represents any integer from 0 to 10. n1’ represents any integer from 0 to 3.

[0043] R a01 、R a4 and R a5 The halogen atoms in R, R, and R include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R a01 、R a4 and R a5Examples of the alkyl group which may have a halogen atom in the above formula include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group. R a01 , R a4 and R a5 is preferably a hydrogen atom or a methyl group, and more preferably a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or *-O-(CH2) k01 It is -CO-O- (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a7 The alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combinations thereof in the formula (1) include R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a02 , R a03 , and R a04 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a6 and Ra7 The alkyl group in a7 is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group or a t-butyl group, and still more preferably an ethyl group, an isopropyl group or a t-butyl group. R a6 and R a7 The alkenyl group in a7 is preferably an alkenyl group having 2 to 6 carbon atoms, more preferably an ethenyl group, a propenyl group, an isopropenyl group or a butenyl group. R a02 、R a03 、R a04 、R a6 and R a7 The number of carbon atoms of the alicyclic hydrocarbon group of a7 is preferably 5 to 12, more preferably 5 to 10. R a02 、R a03 、R a04 、R a6 and R a7 The number of carbon atoms of the aromatic hydrocarbon group of a7 is preferably 6 to 12, more preferably 6 to 10. For the group formed by combining an alkyl group and an alicyclic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and alicyclic hydrocarbon group is 18 or less. For the group formed by combining an alkyl group and an aromatic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and aromatic hydrocarbon group is 18 or less. R a02 and R a03 R and R are preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group which may have a halogen atom. R a04 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group which may have a halogen atom. R a6 and R a7is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkenyl group having 2 to 6 carbon atoms which may have a halogen atom, or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, more preferably a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, a phenyl group or a naphthyl group which may have a halogen atom, and still more preferably an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group or a phenyl group which may have a halogen atom. m1' is preferably any integer from 0 to 3, more preferably 0 or 1. n1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1' is preferably 0 or 1.

[0044] Examples of the structural unit (a1-0) include structural units represented by any of the formulas (a1-0-1) to (a1-0-24) and structural units in which the methyl group corresponding to R in the structural unit (a1-0) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. Structural units represented by any of the formulas (a1-0-1) to (a1-0-10), formula (a1-0-13), formula (a1-0-14), formula (a1-0-19) to (a1-0-24) are preferred. a01 Examples include structural units in which the methyl group corresponding to R in the structural unit (a1-0) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. Structural units represented by any of the formulas (a1-0-1) to (a1-0-10), formula (a1-0-13), formula (a1-0-14), formula (a1-0-19) to (a1-0-24) are preferred. JPEG2025100428000033.jpg119160

[0045] Examples of the structural unit (a1-1) include structural units derived from the monomers described in JP-A-2010-204646. Among them, structural units represented by any of the formulas (a1-1-1) to (a1-1-7) and structural units in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group are preferred, and structural units represented by any of the formulas (a1-1-1) to (a1-1-4) are more preferred. a4 Examples include structural units in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. Structural units represented by any of the formulas (a1-1-1) to (a1-1-4) are more preferred. TIFF2025100428000034.tif39169

[0046] As the structural unit (a1-2), there are a structural unit represented by any one of Formula (a1-2-1) to Formula (a1-2-20) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group, and a structural unit represented by any one of Formula (a1-2-2), Formula (a1-2-5), Formula (a1-2-6) and Formula (a1-2-10) to Formula (a1-2-20) is preferred. a5 When the methyl group corresponding to R in the structural unit (a1-2) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group, examples thereof include a structural unit represented by any one of Formula (a1-2-2), Formula (a1-2-5), Formula (a1-2-6) and Formula (a1-2-10) to Formula (a1-2-20), and a structural unit represented by any one of them is preferred. When the resin (A) contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A1). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 70 mol% or less, even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin (A) contains the structural unit (a1-0), the content thereof is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, even more preferably 25 mol% or more, still even more preferably 30 mol% or more, and even more preferably 35 mol% or more, based on all the structural units of the resin (A1). Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, and even more preferably 60 mol% or less. Specifically, it is 5 to 80 mol%, preferably 5 to 75 mol%, and more preferably 10 to 70 mol%. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units such as the resin (A). Further, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, still more preferably 20 to 80 mol%, and even more preferably 20 to 75 mol%.

[0047] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) include the structural unit represented by the formula (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)"). TIFF2025100428000036.tif4558[In the formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Z a1 represents a single bond or *-(CH2) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, and * represents the bonding site with L 51 . L 51 L 52 L 53 and L 54 each independently represent -O- or -S-. s1 represents an integer of 1 to 3. s1' represents an integer of 0 to 3.]

[0048] R a8Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include R in formula (a1-0). a01 Examples thereof include the same as those exemplified above. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Among them, it is preferable that one is -O- and the other is -S-. s1 is preferably 1. s1' is preferably any integer from 0 to 2. Z a1 is preferably a single bond or *-CH2-CO-O-.

[0049] Examples of the structural unit (a1-5) include structural units derived from the monomers described in JP-A-2010-61117. Among them, the structural units represented by formula (a1-5-1) to formula (a1-5-4) are preferable, and the structural unit represented by formula (a1-5-1) or formula (a1-5-2) is more preferable. When the resin (A) contains the structural unit (a1-5), the content thereof is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, even more preferably 10 mol% or more, still even more preferably 20 mol% or more, and even more preferably 25 mol% or more, based on all the structural units of the resin (A). Also, it is 80 mol% or less, preferably 70 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 45 mol% or less, still even more preferably 40 mol% or less, and even more preferably 30 mol% or less. Specifically, 1 to 50 mol% is preferable, 3 to 45 mol% is more preferable, 5 to 40 mol% is still more preferable, and 5 to 30 mol% is even more preferable.

[0050] Examples of the structural unit (a1) also include the following structural units. TIFF2025100428000038.tif33167

[0051] When the resin (A) or the like contains the structural units represented by the formulas (a1-7-1) to (a1-7-7), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more with respect to all the structural units of the resin (A) or the like. Further, 95 mol% or less is mentioned, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 95 mol% is preferable, 15 to 90 mol% is more preferable, 20 to 85 mol% is still more preferable, 20 to 70 mol% is even more preferable, and 20 to 60 mol% is particularly preferable.

[0052] Examples of the structural unit (a1) also include the following structural units. When the resin (A) contains a structural unit represented by the formulas (a1-8-1) to (a1-8-3), its content is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 60 mol% is preferable, 15 to 55 mol% is more preferable, 20 to 50 mol% is still more preferable, 20 to 45 mol% is even more preferable, and 20 to 40 mol% is particularly preferable.

[0053] 〈Structural unit(s)〉 The structural unit(s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer(s)"). As the monomer from which the structural unit(s) is derived, a monomer having no acid-labile group known in the resist field can be used. As the structural unit(s), it is preferable to have a hydroxy group, a carboxy group or a lactone ring. By using a resin containing a structural unit having a hydroxy group or a carboxy group and not having an acid-labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and not having an acid-labile group (hereinafter sometimes referred to as "structural unit (a3)") in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved. In addition to the above-described structural units, the structural unit(s) includes a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), a structural unit having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"), or other structural units well-known in the art.

[0054] 〈Structural unit (a2)〉 The structural unit (a2) is a structural unit represented by the formula (a2) and has an alcoholic hydroxy group, a phenolic hydroxy group or a carboxy group. TIFF2025100428000040.tif4094[In the formula (a2), R a2 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO- or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. L a21 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. L a22represents an alkanediyl group having 1 to 12 carbon atoms which may have a single bond or a fluorine atom, and -CH2- contained in the alkanediyl may be replaced by -O- or -CO-. na2 represents any integer from 1 to 5. When na2 is 2 or more, a plurality of Ls a22 may be the same as or different from each other.

[0055] R a2 Examples of the halogen atom in R include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. R a2 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group, and the like. R a2 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0056] A a21Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, etc. Preferably it is 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still even more preferably 1 to 3, and still more preferably 1 or 2. R a28 Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group. A a21 When -CH2- contained in the alkanediyl group of a21 A is replaced by -O-, -CO- or -NR a28 , the carbon number before replacement is defined as the carbon number of the hydrocarbon group. A a21 Examples of the group in which -CH2- contained in the alkanediyl group of a21 A is replaced by -O- or -CO- include hydroxy group (the group in which -CH2- contained in the methyl group is replaced by -O-), carboxy group (the group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), carbonyl group (the group in which -CH2- contained in the methylene group is replaced by -CO-), oxy group (the group in which -CH2- contained in the methylene group is replaced by -O-), amino group (the group in which -CH2- contained in the alkanediyl group is replaced by -NR a28-replaced group), alkoxy group (a group in which any -CH2- in the alkyl group is replaced by -O-), alkoxycarbonyl group (a group in which any -CH2-CH2- in the alkyl group is replaced by -O-CO-), alkylcarbonyl group (a group in which any -CH2- in the alkyl group is replaced by -CO-), alkylamino group (a group in which -CH2- contained in the alkyl group is replaced by -NR a28 -replaced group), peptide group (a group in which -CH2-CH2- contained in the ethylene group is replaced by -CO-NR a28 -replaced group), alkanediylamino group (a group in which any -CH2- in the alkanediyl group is replaced by -NR a28 -replaced group), etc. These replaced groups include those similar to those exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. For example, A a21 The -CH2- contained in the alkanediyl group of is replaced by -O-, -CO- or -NR a28 -replaced groups include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a22 -CO-O-, *-O-CO-A a22 -O-, *-O-A a22 -CO-O-, *-CO-O-A a22 -O-CO-, *-O-CO-A a22 -O-CO-, *-CO-NR a28 - are included. Among them, *-CO-O-, *-CO-O-A a22 -CO-O- or *-O-A a22 -CO-O-, *-CO-NR a28 - are preferred. Here, A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site bonded to the carbon atom to which R a2 is bonded. The alkanediyl group of A a22 includes the same alkanediyl group as A a21 within the range where the upper limit of the number of carbon atoms permits. A a21 is a single bond, *-CO-O- or *-CO-O-A a22It is preferably -CO-O-, more preferably a single bond, *-CO-O- or *-CO-O-CH2-CO-O-, and even more preferably a single bond or *-CO-O-.

[0057] L a21 The hydrocarbon group in L is a (na2 + 1)-valent hydrocarbon group, and examples thereof include linear or branched chain hydrocarbon groups, monocyclic or polycyclic (including spiro rings, condensed rings, bridged rings, etc.) alicyclic hydrocarbon groups, and cyclic hydrocarbon groups such as aromatic hydrocarbon groups. A group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group) may also be used. L a21 Examples of the chain hydrocarbon group of L include divalent to hexavalent chain hydrocarbon groups such as alkanediyl groups, alkanetriyl groups, alkanetetrayl groups, alkanepentayl groups, and alkanexayl groups. L a21 Examples of the alkanediyl group of L include, for example, the same alkanediyl group as A a21 L a21 Examples of the alkanetriyl group of L include methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decanetriyl group, undecanetriyl group, dodecanetriyl group, tridecanetriyl group, tetradecanetriyl group, pentadecanetriyl group, hexadecanetriyl group, and heptadecanetriyl group. Examples of the alkanetetrayl group include methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group, decanetetrayl group, undecanetetrayl group, dodecanetetrayl group, tridecanetetrayl group, tetradecanetetrayl group, pentadecanetetrayl group, hexadecanetetrayl group, and heptadecanetetrayl group. ​Examples of the alkanpentyl group include a methanepentyl group, an ethanepentyl group, a propanepentyl group, a butanepentyl group, a pentanepentyl group, a hexanepentyl group, and the like. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. L a21 The number of carbon atoms of the chain hydrocarbon group of L is preferably from 1 to 18, more preferably from 1 to 12, still more preferably from 1 to 10, even more preferably from 1 to 9, still even more preferably from 1 to 8, still more preferably from 1 to 6, still even more preferably from 1 to 5, and particularly preferably from 1 to 4. L a21 Examples of the monocyclic and polycyclic alicyclic hydrocarbon groups in L include the following alicyclic hydrocarbon groups and the like. The bonding site can be at any position. TIFF2025100428000041.tif46167For example, divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanpentyl group, a cycloalkanhexyl group, and the like can be mentioned. Specifically, monocyclic alicyclic hydrocarbon groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclooctane-1,5-diyl group, a cyclopropanetriyl group, a cyclobutanetriyl group, a cyclopentanetriyl group, a cyclohexanetriyl group, a cycloheptanetriyl group, a cyclooctanetriyl group, a cyclodecanetriyl group, a cyclopropanetetrayl group, a cyclobutanetetrayl group, a cyclopentanetetrayl group, a cyclohexanetetrayl group, a cycloheptanetetrayl group, a cyclooctanetetrayl group, a cyclodecanetetrayl group, and Examples of the polycyclic alicyclic hydrocarbon group include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, decahydronaphthalenediyl group, bicyclo[3.3.0]octanediy group, norbornanetril group, adamantanetril group, decahydronaphthalenetril group, bicyclo[3.3.0]octanetril group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, bicyclo[3.3.0]octanetetrayl group, and the like. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, and even more preferably 3 to 12. L a21 Examples of the aromatic hydrocarbon group in L include divalent to hexavalent aromatic hydrocarbon groups such as an arylene group, an arenetricyl group, an arenetetrayl group, an arenepentayl group, and an arenexayl group. Specifically, aromatic hydrocarbon groups such as a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, a benzenetricyl group, a naphthalenetricyl group, an anthracenetricyl group, a biphenylenetricyl group, a phenanthrenetricyl group, a benzenetetrayl group, a naphthalenetetrayl group, an anthracenetetrayl group, a biphenylenetetrayl group, and a phenanthrenetetrayl group can be mentioned. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 20, more preferably 6 to 18, still more preferably 6 to 14, and even more preferably 6 to 10. Examples of the trivalent to pentavalent alicyclic hydrocarbon group and aromatic hydrocarbon group include a group in which 1 to 3 hydrogen atoms are removed from the above-described divalent group to form a bond. Examples of the group formed by combining two or more groups include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group, a group formed by combining an alicyclic hydrocarbon group, a chain hydrocarbon group, and an aromatic hydrocarbon group, and the like. In the combination, two or more alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined respectively. Further, any group may be bonded to A a21 and L a22 as well. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -SO2-), an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group,Examples include an aromatic hydrocarbon group-carbonyl oxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group formed by combining two or more of these groups. Also included are groups in which one or more hydrogen atoms of these groups are replaced at the bonding site. These replaced groups include, within the range allowed by the upper limit of the number of carbon atoms, those similar to the groups exemplified in this specification.

[0058] Examples of groups in which -CH2- contained in an alicyclic hydrocarbon group and a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include, within the range allowed by the upper limit of the number of carbon atoms, those similar to the groups exemplified in this specification. L a21 The hydrocarbon group in may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the haloalkyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-), an acryloyloxy group or a methacryloyloxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. L a21 By having a halogen atom as a substituent, the hydrocarbon group in can substantially have a substituent such as a haloalkyl group. Examples of the haloalkyl group include a chloromethyl group, a bromomethyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluorobutyl group and the like. A haloalkyl group having 1 to 4 carbon atoms is preferred, and a haloalkyl group having 1 to 3 carbon atoms is more preferred. L a21 The hydrocarbon group of may include a branched structure, whereby L a21may substantially have substituents such as an alkyl group. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, and the like. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. L a21 is a group in which -CH2- contained in the hydrocarbon group of L is replaced by -O-, -CO-, -S- or -SO2-. a21 may substantially have substituents such as a hydroxy group, a carboxy group, a thiol group, a sulfonyl group, an alkoxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, and the like. These groups include those exemplified in the present specification and similar ones as long as the upper limit of the number of carbon atoms permits. L a21 Preferred substituents that the hydrocarbon group in L may have include a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-). More preferred are a fluorine atom, an iodine atom, a haloalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-). Even more preferred are a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group. L a21is preferably a group formed by combining a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or an optionally substituted chain hydrocarbon group having 1 to 8 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-); more preferably, it is a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or an optionally substituted chain hydrocarbon group having 1 to 6 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-).

[0059] L a22Examples of the chain hydrocarbon group having 1 to 12 carbon atoms include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-dimethylpropane-1,3-diyl group, pentane-2,4-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc. The carbon number of the alkanediyl is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. Examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O- or -CO- include those similar to those exemplified herein, within the range where the upper limit of the carbon number is allowed. L a22 The fluorine atom that L has may be one or two or more. na2 is preferably any integer from 1 to 4, more preferably any integer from 1 to 3, and still more preferably 1 or 2. L a21 Examples of the structural unit (a2) when L is a single bond or a chain hydrocarbon group include, for example, the following structural units. Among the following structural units, the methyl group corresponding to R a2 replaced by a hydrogen atom or the like is also a preferred structural unit of the structural unit (a2) in the same manner as the following structural units. TIFF2025100428000042.tif66164

[0060] When producing a resist pattern from the resist composition of the present invention, when using a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) as an exposure light source, as the structural unit (a2), a structural unit (a2) having a phenolic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-A) described later. When using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-1) described later. As the structural unit (a2), one kind may be contained alone, or two or more kinds may be contained.

[0061] In the structural unit (a2), when L a21 is a cyclic hydrocarbon group, examples of the structural unit having a phenolic hydroxy group or a carboxy group include a structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF2025100428000043.tif30128[In the formula (a2-A), R a2 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO-, or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a2 represents a single bond or a carbonyl group. nA2 represents any integer from 1 to 5. When nA2 is 2 or more, the groups within the plurality of parentheses may be the same as or different from each other. na21 represents any integer from 0 to 4. When na21 is 2 or more, the plurality of R a27 may be the same as or different from each other. mc represents any integer from 0 to 2.

[0062] R a2 and A a21 are each exemplified by the same groups as those in formula (a2). R a2 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a27 Examples of the halogen atom of R include a fluorine atom, a chlorine atom, an iodine atom, a bromine atom and the like. R a27 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom of R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, even more preferably a methyl group or an ethyl group, and still more preferably a methyl group. R a27Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 4, more preferably 1 to 3, still more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a27 Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and still more preferably a methoxymethyl group. R a27 Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. R a27 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a27 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an optionally halogenated C1-C4 alkyl group, a C1-C4 alkoxy group or a C2-C8 alkoxyalkoxy group, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nA2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na21 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. mc is preferably 0 or 1. -X a2 -OH, in the case of a benzene ring, may be bonded to any of the o-position, m-position or p-position with respect to the bonding position of A a21 . Among them, at least one is preferably bonded to the m-position or p-position, and more preferably bonded to the m-position. In the case of a naphthalene ring, when the bonding position of A a21 is at the 1-position, it may be bonded to any of the 2-position to 8-position, and when the bonding position of A a21 is at the 2-position, it may be bonded to any of the 1-position and the 3-position to 8-position. Among them, when the bonding position of A a21 is at the 1-position, at least one is preferably bonded to the 3-position to 6-position, and more preferably bonded to the 3-position or 4-position. When the bonding position of A a21 is at the 2-position, it is preferably bonded to the 4-position to 7-position, and more preferably bonded to the 5-position or 6-position.

[0063] Examples of the structural unit (a2-A) include structural units derived from the monomers described in JP-A-2010-204634 and JP-A-2012-12577. Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-32), Formula (a2-3-1) to Formula (a2-3-24), and structural units represented by Formula (a2-2-1) to Formula (a2-2-32), Formula (a2-3-1) to Formula (a2-3-24), where the methyl group corresponding to R in the structural unit (a2-A) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. a2 Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-32), Formula (a2-3-1) to Formula (a2-3-24), and structural units represented by Formula (a2-2-1) to Formula (a2-2-32), Formula (a2-3-1) to Formula (a2-3-24), where the methyl group corresponding to R in the structural unit (a2-A) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2025100428000044.tif107170

[0064] When the resin (A) contains the structural unit (a2-A), the content of the structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 15 mol% or more, even more preferably 20 mol% or more, based on all the structural units. Also, it is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, even more preferably 60 mol% or less, still even more preferably 50 mol% or less, still more preferably 45 mol% or less, and even more preferably 40 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, still more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%. The structural unit (a2-A) can be incorporated into the resin (A) by polymerizing a compound that induces the structural unit (a2-A) (for example, a compound (a2-A') in which -CH2-C(-R a2 )- in the structural unit (a2-A) is in the state of CH2=C(-R a2 ) of the double bond before cleavage). Further, for example, after polymerization using the structural unit (a1-4), it can be incorporated into the resin (A) by treatment with an acid such as p-toluenesulfonic acid. Also, after polymerization using acetoxystyrene or the like, the structural unit (a2-A) can be incorporated into the resin (A) by treatment with an alkali such as tetramethylammonium hydroxide.

[0065] In the structural unit (a2), when L a21 is a cyclic hydrocarbon group, examples of the structural unit having an alcoholic hydroxy group or a carboxy group include a structural unit represented by formula (a2-B) (hereinafter sometimes referred to as "structural unit (a2-B)"), a structural unit represented by formula (a2-C) (hereinafter sometimes referred to as "structural unit (a2-C)"), and a structural unit represented by formula (a2-D) (hereinafter sometimes referred to as "structural unit (a2-D)"). TIFF2025100428000046.tif45100[In formula (a2-B) and formula (a2-C), R a2 represents the same meaning as in formula (a2). R a27 represents the same meaning as in formula (a2-A). L a25 represents -O- or *-O-(CH2) k2 -CO-O-, k2 represents any integer from 1 to 7. * represents the bonding site with -CO-. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represent a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents any integer from 1 to 5. When nB2 is 2 or more, the plurality of Xs a2 may be the same as or different from each other. nB22 represents any integer from 0 to 8. When nB22 is 2 or more, the plurality of Rs a27 may be the same as or different from each other. nC22 represents any integer from 0 to 10. When nC22 is 2 or more, the plurality of Rs a27 may be the same as or different from each other.] L a25 is preferably -O-, -O-(CH2) f1 -CO-O- (wherein f1 represents any integer from 1 to 4), and more preferably -O-. R a2is preferably a methyl group. X a2 is preferably a single bond. R a25 is preferably a hydrogen atom. R a26 is preferably a hydrogen atom or a hydroxy group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, an optionally halogenated alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nB2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. nB22 is preferably any integer from 0 to 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. nC22 is preferably any integer from 0 to 6, more preferably any integer from 0 to 3, and even more preferably 0 or 1.

[0066] Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from the monomers described in JP-A-2010-204646, the following structural units, and methyl groups or hydrogen atoms corresponding to R in the following structural units, which are replaced with hydrogen atoms, halogen atoms, haloalkyl groups or other alkyl groups. Among them, the structural units represented by any of formula (a2-B-1) to formula (a2-B-5) and formula (a2-C-1) to formula (a2-C-9) are preferred. a2 Examples thereof include structural units in which the methyl group or hydrogen atom corresponding to R is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. Among them, the structural units represented by any of formula (a2-B-1) to formula (a2-B-5) and formula (a2-C-1) to formula (a2-C-9) are preferred. When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on all the structural units of the resin (A). Further, it is 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, still more preferably 20 mol% or less, and even more preferably 10 mol% or less. Specifically, 1 to 45 mol% is mentioned, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, still more preferably 1 to 20 mol% or 2 to 20 mol%, and even more preferably 1 to 10 mol% or 2 to 10 mol%.

[0067] TIFF2025100428000048.tif51106[In the formula (a2-D), R a2 and A a21 each represent the same meaning as in the formula (a2). R a27 represents the same meaning as in the formula (a2-A). R a21 and R a22 each independently represent an alkyl fluoride group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents any integer from 1 to 5. When nD2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. nD22 represents any integer from 0 to 4. When nD22 is 2 or more, the plurality of R a27 may be the same as or different from each other. However, 1 ≦ nD2 + nD22 ≦ 5.] R a21 and R a22 As the alkyl fluoride groups of R and R a21and R a22 is preferably a trifluoromethyl group. L a24 Examples of the alkanediyl group of L include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, and the like. L a24 is preferably a single bond or a methylene group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxy-methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nD2 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, even more preferably 1 or 2, and even more preferably 1. Further, preferably, nD2 is 1 and the group in parentheses is bonded to the para position. nD22 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2, even more preferably 0 or 1, and even more preferably 0.

[0068] As the structural unit (a2-D), a structural unit represented by the following formula (a2-D1) (hereinafter, may be referred to as "structural unit (a2-D1)") is more preferable. TIFF2025100428000049.tif51107[In formula (a2-D1), R a2 , A a21 , R a27 , na2 and na21 represent the same meanings as in formula (a2-D).] In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group. A a21 is preferably a single bond.

[0069] Examples of the structural unit (a2-D) include the structural units described below. TIFF2025100428000050.tif62167

[0070] In the structural units represented by formula (a2-D-1) to formula (a2-D-8), the hydrogen atom corresponding to R a2 and the structural units in which the hydrogen atom corresponding to R is replaced by a methyl group or the like, and the structural units represented by formula (a2-D-9) to formula (a2-D-16), in which the methyl group corresponding to R a2 is replaced by a hydrogen atom or the like can also be cited as specific examples of the structural unit (a2-D). Among them, the structural units represented by formula (a2-D-1) to formula (a2-D-8) are preferred, the structural units represented by formula (a2-D-1) to formula (a2-D-4) are more preferred, and the structural unit represented by formula (a2-D-1) is even more preferred.

[0071] When the resin (A) contains the structural unit (a2-D), its content is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on all the structural units of the resin (A). Also, it is preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, and still more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 10 to 70 mol%, and still more preferably 10 to 65 mol%.

[0072] 〈Structural unit (a3)〉 The lactone ring of the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, γ-butyrolactone ring, or δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, the structural unit represented by the following formula (a3-2)) can be cited.

[0073] The structural unit (a3) is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3) or formula (a3-4). These may be contained alone or in combination of two or more. TIFF2025100428000051.tif48155[In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 、L a5 and L a6 each independently represents a group represented by -O- or *-O-(CH2) k3 -CO-O- (where k3 represents an integer from 1 to 7). L a7 represents -O-, *-O-L a8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding position to the carbonyl group. R a18 、R a19 、R a20 and R a24 each independently represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 、R a23 and R a25 each independently represents a carboxy group, a cyano group or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer from 0 to 5. q1 represents an integer from 0 to 3. r1 represents an integer from 0 to 3. w1 represents an integer from 0 to 8. When p1, q1, r1, and / or w1 is 2 or more, a plurality of Rs a21 , R a22 , R a23 and / or R a25 may be the same as or different from each other.

[0074] R a21 , R a22 , R a23 and R a25 Examples of the aliphatic hydrocarbon group in R, R, R, and R include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, and tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom and the alkyl group which may have a halogen atom in R, R, R, and R are the same as those exemplified by R of formula (a1-0) a01 and the like. L a8 and L a9 Examples of the alkanediyl group in L and L include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. L a4 ~L a6 are each independently preferably -O- or, in *-O-(CH2) k3 -CO-O-, a group in which k3 is an integer from 1 to 4, more preferably -O- and, *-O-CH2-CO-O-, even more preferably an oxygen atom. L a7 is preferably -O- or *-O-L a8 -CO-O-, more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. R a18 , Ra19 and R a20 and R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group. R a21 is preferably a methyl group. R a22 and R a23 and R a25 are each independently preferably a carboxy group, a cyano group or a methyl group. p1, q1 and r1 are each independently preferably any integer from 0 to 2, more preferably 0 or 1. w1 is preferably any integer from 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)'. TIFF2025100428000052.tif3848 (wherein R a24 and L a7 represent the same meaning as above.)

[0075] Examples of the structural unit (a3) include structural units derived from the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. Examples of the structural unit (a3) include structural units represented by any of formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2), formula (a3-3-1), formula (a3-3-2) and formula (a3-4-1) to formula (a3-4-12), and, in the above structural units, structural units in which the methyl groups corresponding to R a18 and R a19 and R a20 and R a24 are replaced by hydrogen atoms are preferred. TIFF2025100428000053.tif108164

[0076] When the resin (A) contains the structural unit (a3), the total content is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and still more preferably 10 mol% or more with respect to all the structural units of the resin (A). Also, 70 mol% or less is mentioned, preferably 65 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still even more preferably 30 mol% or less, even more preferably 25 mol% or less, and still even more preferably 20 mol% or less. Specifically, 1 to 70 mol% is mentioned, preferably 1 to 65 mol%, more preferably 1 to 60 mol%, and still more preferably 3 to 60 mol%. Also, the content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3), or the structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, and even more preferably 10 mol% or more with respect to all the structural units of the resin (A). Also, it is preferably 60 mol% or less, more preferably 55 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still even more preferably 30 mol% or less, even more preferably 25 mol% or less, and still even more preferably 20 mol% or less. Specifically, 1 to 60 mol% is preferable, 3 to 50 mol% is more preferable, and 5 to 50 mol% is still more preferable.

[0077] 〈Structural unit (a4)〉 The structural unit represented by the formula (a4) is shown below. TIFF2025100428000054.tif2770[In the formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents an aliphatic hydrocarbon group having a halogen atom with 1 to 48 carbon atoms, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-.]

[0078] R 42 The aliphatic hydrocarbon group represented by 42 includes a linear or branched chain hydrocarbon group, a monocyclic or polycyclic alicyclic hydrocarbon group, and a group formed by combining these, etc. Examples of the chain hydrocarbon group include linear alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, hexadecyl group, heptadecyl group, and octadecyl group; and branched alkyl groups such as isopropyl group and isobutyl group. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include monocyclic alicyclic hydrocarbon groups that are monocyclic cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooctyl group; and polycyclic alicyclic hydrocarbon groups that are polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group, and the following group (* represents the bonding site). Examples of the group formed by the combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, -alkanediyl group-alicyclic hydrocarbon group-alkyl group, etc. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, and hexane-1,6-diyl group; and branched alkanediyl groups such as propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom contained in 42 include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R 42Examples of the group in which -CH2- of the aliphatic hydrocarbon group contained in the formula is replaced by -O- or -CO- include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanedioxy group, an alkanedioxycarbonyl group, an alkanedicarbonyl group, an alkanedicarbonyl oxy group, a cycloalkoxy group, a cycloalkylalkoxy group, a group formed by combining two or more of these groups, and the like. These replaced groups include the same groups as those exemplified in the present specification within the range where the upper limit of the number of carbon atoms permits.

[0079] The structural unit (a4) is preferably such that R 42 is an aliphatic hydrocarbon group having a fluorine atom, and examples of the structural unit (a4) in which R 42 is an aliphatic hydrocarbon group having a fluorine atom include a structural unit represented by the formula (a4-1) (hereinafter sometimes referred to as "structural unit (a4-1)"), a structural unit represented by the formula (a4-2) (hereinafter sometimes referred to as "structural unit (a4-2)"), a structural unit represented by the formula (a4-3) (hereinafter sometimes referred to as "structural unit (a4-3)"), and a structural unit represented by the formula (a4-A) (hereinafter sometimes referred to as "structural unit (a4-A)"). The structural unit represented by the formula (a4-1) is the structural unit shown below. TIFF2025100428000056.tif3092[In the formula (a4-1), R 41 represents a hydrogen atom or a methyl group. L 41 represents a single bond or an alkanedioyl group having 1 to 4 carbon atoms. L 42f represents an alkanedioyl group having 1 to 8 carbon atoms and having a fluorine atom or a cycloalkanedioyl group having 3 to 12 carbon atoms and having a fluorine atom. R 42f represents a hydrogen atom or a fluorine atom.]

[0080] L 41Examples of the alkanediyl group in [context] include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, etc., and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group and 2-methylpropane-1,2-diyl group. The terminal of the branched alkanediyl group may be a methyl group. L 42f Examples of the alkanediyl group having a fluorine atom in [context] include linear alkanediyl groups having a fluorine atom such as methylene group having a fluorine atom, ethylene group having a fluorine atom, propane-1,3-diyl group having a fluorine atom, butane-1,4-diyl group having a fluorine atom, pentane-1,5-diyl group having a fluorine atom, hexane-1,6-diyl group having a fluorine atom, heptane-1,7-diyl group having a fluorine atom, octane-1,8-diyl group having a fluorine atom, etc.; branched alkanediyl groups having a fluorine atom such as ethane-1,1-diyl group having a fluorine atom, propane-1,1-diyl group having a fluorine atom, propane-1,2-diyl group having a fluorine atom, propane-2,2-diyl group having a fluorine atom, pentane-2,4-diyl group having a fluorine atom, 2-methylpropane-1,3-diyl group having a fluorine atom, 2-methylpropane-1,2-diyl group having a fluorine atom, pentane-1,4-diyl group having a fluorine atom, 2-methylbutane-1,4-diyl group having a fluorine atom. The terminal of the branched alkanediyl group may be a methyl group which may have a fluorine atom. L 42f Examples of the cycloalkanediyl group having a fluorine atom in [context] include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group having a fluorine atom, cyclopentane-1,3-diyl group having a fluorine atom, cyclohexane-1,4-diyl group having a fluorine atom, cyclohexene-3,6-diyl group having a fluorine atom, cyclooctane-1,5-diyl group having a fluorine atom, etc., Examples of the polycyclic cycloalkanediyl group having a fluorine atom include a norbornane-1,4-diyl group having a fluorine atom, a norbornane-2,5-diyl group having a fluorine atom, a 5-norbornene-2,3-diyl group having a fluorine atom, an adamantane-1,5-diyl group having a fluorine atom, and an adamantane-2,6-diyl group having a fluorine atom. L 42f The number of fluorine atoms in the alkanediyl group having a fluorine atom and the cycloalkanediyl group having a fluorine atom in may be 1 or more, and is preferably 2 or more. L 42f The alkanediyl group having a fluorine atom and the cycloalkanediyl group having a fluorine atom in are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0081] L 42f Examples of the perfluoroalkanediyl group in include a difluoromethylene group, a perfluoroethylene group, a perfluoroethylfluoromethylene group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, a perfluoropentane-1,5-diyl group, a perfluoropentane-2,2-diyl group, a perfluoropentane-3,3-diyl group, a perfluorohexane-1,6-diyl group, a perfluorohexane-2,2-diyl group, a perfluorohexane-3,3-diyl group, a perfluoroheptane-1,7-diyl group, a perfluoroheptane-2,2-diyl group, a perfluoroheptane-3,4-diyl group, a perfluoroheptane-4,4-diyl group, a perfluorooctane-1,8-diyl group, a perfluorooctane-2,2-diyl group, a perfluorooctane-3,3-diyl group, and a perfluorooctane-4,4-diyl group. L 42fExamples of the perfluorocycloalkanediyl group include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, a perfluoroadamantanediyl group, and the like.

[0082] L 41 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms, more preferably a single bond, a methylene group or an ethylene group, and even more preferably a single bond or a methylene group. L 42f is preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and even more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0083] Examples of the structural unit (a4-1) include the structural units shown below and the structural units in which the methyl group corresponding to R in the following structural units is replaced with a hydrogen atom in the structural unit (a4-1). 41 TIFF2025100428000057.tif55167

[0084] The structural unit represented by the formula (a4-2) is the structural unit shown below. TIFF2025100428000058.tif33101[In the formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. R 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L 43f and R 43fAt least one of them has a fluorine atom, and L 43f and R 43f The upper limit of the total number of carbon atoms is 21.]

[0085] L 43f and R 43f Examples of the aliphatic hydrocarbon group in L 43f and R 43f include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these, etc. Examples of the aliphatic hydrocarbon group in L 43f and R 43f include groups similar to the aliphatic hydrocarbon groups exemplified as long as the upper limit of the total number of carbon atoms in L 42 and R

[0086] L 43f The aliphatic hydrocarbon group of is preferably an alkanediyl group having 1 to 6 carbon atoms or a group represented by the formula (L43f-1). TIFF2025100428000059.tif13120[In the formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represent a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. L 47f represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. X 46f and X 47f each independently represent -O-, -CO-, -CO-O- or -O-CO-. However, the total number of carbon atoms in L 45f , L 46f , L 47f , X 46f and X 47f is 7 or less. * and ** are bonding sites, and ** is the bonding site with -O-CO-R 43f .

[0087] L in the group represented by formula (L43f-1) 45f L 46f and L 47f Examples of the divalent aliphatic hydrocarbon group represented by include linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic hydrocarbon groups, and divalent aliphatic hydrocarbon groups formed by combining an alkanediyl group and a divalent alicyclic hydrocarbon group. Specifically, examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, and the like. s is preferably 0.

[0088] Examples of the group represented by formula (L43f-1) include the following groups. In the following examples, * and ** each represent a bonding site, and ** is the bonding site with -O-CO-R 43f . TIFF2025100428000060.tif47140

[0089] R 43f is preferably an aliphatic hydrocarbon group having a fluorine atom. Examples of the structural unit represented by formula (a4-2) in this case include the structural units represented by formula (a4-2A) or (formula a4-2B). TIFF2025100428000061.tif41157[In formula (a4-2A) and formula (a4-2B), R 41 and L 43f represent the same as those in formula (a4-2). R 43fA represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms and having a fluorine atom. A 43f represents a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** is A43f Represents the binding site with R 43fB represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, in formula (a4-2A), L 43f and R 43fA The total number of carbon atoms of is 21 or less. In formula (a4-2B), L 43f , A 43f , X 43 and R 43fB The total number of carbon atoms of is 21 or less. Among A 43f and R 43fB at least one of them has at least one fluorine atom.] R 43fA The aliphatic hydrocarbon group of is, as long as the upper limit of the number of carbon atoms permits, the same aliphatic hydrocarbon group as the aliphatic hydrocarbon group exemplified by R 42 can be mentioned. R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and having a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms and having a fluorine atom, or a group combining them, *-(CF2) n43f -R 42’ (* represents the binding site with the carbonyl group. n43f represents any integer from 1 to 6. R 42’ represents a hydrogen atom or a fluorine atom.) or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferable. A 43f and R 43fB The aliphatic hydrocarbon groups of are, as long as the upper limit of the number of carbon atoms permits, the same aliphatic hydrocarbon groups as the aliphatic hydrocarbon groups exemplified by R 42 in formula (a4). A 43f is preferably a divalent chain hydrocarbon group which may have a fluorine atom, a divalent alicyclic hydrocarbon group, or a group combining them, more preferably a divalent chain hydrocarbon group having a fluorine atom, and even more preferably a fluorinated alkanediyl group having 1 to 6 carbon atoms. R 43fBThe aliphatic hydrocarbon group which may have a fluorine atom is preferably a chain hydrocarbon group, an alicyclic hydrocarbon group or a combination thereof which may have a fluorine atom, more preferably an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or a combination thereof which may have a fluorine atom, and trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, pentyl group, hexyl group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group, perfluorooctyl group and other alkyl fluoride groups, cyclopropylmethyl group, cyclopropyl group, cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantylmethyl group and the like are more preferable.

[0090] In formula (a4-2B), *-A f43 -X 43 -R f43B An example of the structure that the group represented by can take is the following structure (* is the bonding site with the carbonyl group). TIFF2025100428000062.tif15170

[0091] As the structural unit represented by formula (a4-2A), there may be mentioned the following structural units and the structural units in which the methyl group corresponding to R in the structural unit represented by formula (a4-2A) below is replaced by a hydrogen atom. 41 TIFF2025100428000063.tif99167

[0092] Examples of the structural unit represented by formula (a4-2B) include the following structural units and structural units in which the methyl group corresponding to R in the following structural units and represented by formula (a4-2B) is replaced with a hydrogen atom. 41 Examples include structural units in which the methyl group corresponding to R is replaced with a hydrogen atom. TIFF2025100428000064.tif111164

[0093] Examples of the structural unit (a4) also include the structural unit represented by formula (a4-3). TIFF2025100428000065.tif3589[In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. R 44f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. However, at least one of L 44f and R 44f has a fluorine atom, and the upper limit of the total number of carbon atoms of L 44f and R 44f is 21.]

[0094] Examples of the aliphatic hydrocarbon group in L 44f and R 44f include linear or branched chain aliphatic hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these. Examples of the aliphatic hydrocarbon group in L 44f and R 44f are, as long as the upper limit of the total number of carbon atoms of L 44f and R 44f allows it, the same groups as the aliphatic hydrocarbon groups exemplified as the aliphatic hydrocarbon group of R 42 in formula (a4). L 44fis preferably an alkanediyl group having 1 to 14 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 - or -(CH2) j4 -CO-O-(CH2) j5 - (where j1 to j5 each independently represent an integer of 1 to 6). More preferably, it is an alkanediyl group having 1 to 4 carbon atoms (where one -CH2- contained in the alkanediyl group may be replaced by -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced by -CO-O- or -O-CO-). R 44f is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, an alicyclic hydrocarbon group having 3 to 10 carbon atoms having a fluorine atom, or a group combining them, still more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms having a fluorine atom.

[0095] Examples of the structural unit represented by the formula (a4-3) include structural units represented by the following structural units and the following formulas, in which the methyl group corresponding to R in the structural unit (a4-3) is replaced by a hydrogen atom. 41 TIFF2025100428000066.tif85170

[0096] Examples of the structural unit (a4) also include a structural unit represented by the formula (a4-A). TIFF2025100428000067.tif3686 [In the formula (a4-A), all symbols represent the same meaning as described above.]

[0097] R 1 ​The alkyl group having 1 to 6 carbon atoms in [compound name] includes a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R 1 Examples of the halogen atom in [compound name] include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 1 Examples of the alkyl group having 1 to 6 carbon atoms and having a halogen atom in [compound name] include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, a dibromomethyl group, and the like. R 1 R is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0098] L 1 Examples of the aliphatic hydrocarbon group in [compound name] include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.) alicyclic hydrocarbon group, and a group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group) may also be used. Examples of the chain hydrocarbon group include divalent to pentavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, and an alkanepentayl group. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Also, groups in which one or more hydrogen atoms of the above-described groups are replaced with bonding sites, and the like can be mentioned. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, still more preferably 1 to 10, even more preferably 1 to 9, still even more preferably 1 to 8, still more preferably 1 to 6, still even more preferably 1 to 5, and particularly preferably 1 to 4.

[0099] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups, etc. The bonding site can be at any position. TIFF2025100428000068.tif45164 For example, alicyclic hydrocarbon groups such as cycloalkanediyl groups, etc. can be mentioned. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group, and Polycyclic alicyclic hydrocarbon groups such as spiro rings having a cycloalkanediyl group such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, a decahydronaphthalenediyl group, a bicyclo[3.3.0]octanediyl group, a spirocyclohexane-1,2'-cyclopentane-diyl group, a spiroadamantane-2,3'-cyclopentane-diyl group, etc., or a cycloalkanediyl group spiro-bonded to a norbornyl group or an adamantyl group respectively. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, and even more preferably 3 to 12.

[0100] Examples of the group combined with two or more kinds include a group combining an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, the alicyclic hydrocarbon group and the chain hydrocarbon group may each be combined with two or more kinds. Also, any of the groups may be bonded to X 11 It may be bonded. Examples of the group combining an alicyclic hydrocarbon group and a chain hydrocarbon group include a group in which an alicyclic hydrocarbon group is bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which an alicyclic hydrocarbon group, a chain hydrocarbon group, and an alicyclic hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group, an alicyclic hydrocarbon group, and a chain hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), etc. * represents the bonding site with X 11 It represents the bonding site with X.

[0101] L 1 In the aliphatic hydrocarbon group having 1 to 28 carbon atoms of L, -CH2- may be replaced by -O-, -S-, -SO2- or -CO-. L 1 When -CH2- contained in the aliphatic hydrocarbon group of L is replaced by -O-, -S-, -SO2- or -CO-, the number of carbon atoms before replacement is taken as the number of carbon atoms of the aliphatic hydrocarbon group. Examples of the group in which -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group, a carboxy group, a thiol group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, a group formed by combining two or more of these groups, and the like. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. Also included are groups in which one or more hydrogen atoms of the above-described groups are replaced by a bonding site, and the like. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits.

[0102] L 1 The aliphatic hydrocarbon group in may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms (in the alkyl group or the alicyclic hydrocarbon group, -CH2- may be replaced by -O- or -CO-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. The haloalkyl group having 1 to 4 carbon atoms includes a fluoroalkyl group having 1 to 4 carbon atoms, a chloroalkyl group having 1 to 4 carbon atoms, a bromoalkyl group having 1 to 4 carbon atoms, an iodoalkyl group having 1 to 4 carbon atoms and the like. Examples of the haloalkyl group include a perfluoroalkyl group having 1 to 4 carbon atoms (such as a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, etc.), a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, a 3,3,4,4,4-pentafluorobutyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group and the like. The number of carbon atoms of the haloalkyl group is preferably 1 to 3, more preferably 1 or 2. Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 9, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. When -CH2- contained in the alkyl group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the alkyl group. Examples of the replaced group include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group and the like. L 1Examples of the substituent that the aliphatic hydrocarbon group in [Compound Name] may have include a halogen atom, a haloalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms (wherein -CH2- contained in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). A fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-) is more preferable. A fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group is even more preferable. L 1 is R 3When it does not form an alkyl fluoride group and an alicyclic hydrocarbon group, it may have a substituent, a chain hydrocarbon group having 1 to 12 carbon atoms (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), preferably a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent, or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), more preferably a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent, a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining an alicyclic hydrocarbon group having 5 to 12 carbon atoms, a chain hydrocarbon group having 1 to 6 carbon atoms, and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), even more preferably.

[0103] R 2Examples of the C1-C8 fluoroalkyl group in [text] include difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1-(trifluoromethyl)-1,2,2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis(trifluoro)methyl-2,2,2-trifluoroethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2-(perfluorobutyl)ethyl group, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group, perfluorohexyl group, perfluoroheptyl group, perfluorooctyl group. The carbon number of the fluoroalkyl group is preferably 1-6, more preferably 1-5, still more preferably 1-4, and even more preferably 1-3. R 3 In [text], the C1-C6 fluoroalkyl group, as long as the upper limit of the carbon number permits, includes the C1-C6 fluoroalkyl groups exemplified for the fluoroalkyl group of 2 R. R 2 is preferably a C1-C6 fluoroalkyl group, more preferably a C1-C3 fluoroalkyl group, still more preferably a trifluoromethyl group, perfluoroethyl group or perfluoropropyl group, and even more preferably a trifluoromethyl group when 3 R is a C1-C6 fluoroalkyl group. R2 is, when R 3 is a hydrogen atom, preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride group having 1 to 5 carbon atoms, and still more preferably an alkyl fluoride group having 3 to 5 carbon atoms. R 3 is L 1 and combines to form an alicyclic hydrocarbon group having 3 to 6 carbon atoms, R 3 is L 1 Examples of the group formed by the combination with include groups represented by the following formulas. Among the following formulas, * and ** represent bonding sites, and two ** represent that one represents the bonding site with a hydroxy group and the other represents the bonding site with R 2 and the bonding site with, and L 1A is, L 1 is a part of the hydrocarbon group of, and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. TIFF2025100428000069.tif22138R 3 is preferably a hydrogen atom or an alkyl fluoride group having 1 to 3 carbon atoms. mi is preferably any integer from 1 to 3, more preferably 1 or 2, and still more preferably 1.

[0104] Examples of the structural unit (a4-A) include the following structural units and the like. In the following structural units, structural units in which the methyl group corresponding to R 1 is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or an alkyl group other than a methyl group, and structural units in which the hydrogen atom corresponding to R 1 is replaced with a halogen atom, a haloalkyl group or an alkyl group can also be cited as specific examples of the structural unit (a4-A). TIFF2025100428000070.tif192167

[0105] When the resin (A) has the structural unit (a4), its content is preferably 1 to 97 mol%, more preferably 2 to 95 mol%, and still more preferably 3 to 90 mol% based on all the structural units of the resin (A).

[0106] <Structural unit (a5)> Examples of the non-detachable hydrocarbon group in the structural unit (a5) include groups having a linear, branched or cyclic hydrocarbon group. Among them, the structural unit (a5) preferably has a group having an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by formula (a5-1). TIFF2025100428000071.tif3351[In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0107] R 52 The alicyclic hydrocarbon group in R may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group and a 2-ethylhexyl group. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group.

[0108] L 55Examples of the divalent saturated hydrocarbon group in [compound name] include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, preferably a divalent chain saturated hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include alkane diyl groups such as a methylene group, an ethylene group, a propane diyl group, a butane diyl group, and a pentane diyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic divalent alicyclic saturated hydrocarbon group include cycloalkane diyl groups such as a cyclopentane diyl group and a cyclohexane diyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include an adamantane diyl group and a norbornane diyl group.

[0109] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced with -O- or -CO- include the groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom. TIFF2025100428000072.tif19164[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents the bonding site with L x1 .). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the total number of carbon atoms of L x1 and L x2 is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the total number of carbon atoms of L x3 and L x4 is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms of L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, the total number of carbon atoms of L x8 , L x9 and W x1 is 15 or less.

[0110] L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0111] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF2025100428000073.tif37148 Examples of the group represented by the formula (L1-2) include the following divalent groups. TIFF2025100428000074.tif23130 Examples of the group represented by the formula (L1-3) include the following divalent groups. TIFF2025100428000075.tif16147 Examples of the group represented by the formula (L1-4) include the following divalent groups. TIFF2025100428000076.tif13168L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0112] Examples of the structural unit (a5-1) include the following structural units and the structural units in the following structural units where the methyl group corresponding to R in the structural unit (a5-1) is replaced by a hydrogen atom. 51 are mentioned. TIFF2025100428000077.tif104151 When the resin (A) has the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, still more preferably 3 to 15 mol% based on all the structural units of the resin (A).

[0113] 〈Structural unit (a6)〉 The structural unit (a6) is a structural unit having a -SO2- group, and preferably has a -SO2- group in the side chain. The structural unit having a -SO2- group may have a linear structure having a -SO2- group, a branched structure having a -SO2- group, or a cyclic structure (monocyclic and polycyclic structures) having a -SO2- group. Preferably, it is a structural unit having a cyclic structure having a -SO2- group, and more preferably, it is a structural unit having a cyclic structure (sultone ring) containing -SO2-O-.

[0114] Examples of the sultone ring include the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and formula (T 1 -4). The bonding site can be at any position. The sultone ring may be monocyclic, but is preferably polycyclic. The polycyclic sultone ring means a bridged ring containing -SO2-O- as an atomic group constituting the ring, and examples include the rings represented by formula (T 1 -1) and formula (T 1 -2). The sultone ring may contain, in addition to -SO2-O-, a hetero atom as an atomic group constituting the ring, like the ring represented by formula (T 1 -2). Examples of the hetero atom include an oxygen atom, a sulfur atom or a nitrogen atom, and preferably an oxygen atom. TIFF2025100428000078.tif2977

[0115] The sultone ring may have a substituent, and examples of the substituent include a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an alkylcarbonyl group having 2 to 4 carbon atoms.

[0116] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and a decyl group. Preferably, it is an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group. Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. Preferably, a trifluoromethyl group is included. Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a hydroxyalkyl group such as a 2-hydroxyethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkoxycarbonyl group include a group in which an alkoxy group such as a methoxycarbonyl group and an ethoxycarbonyl group is bonded to a carbonyl group. Preferably, an alkoxycarbonyl group having 6 or less carbon atoms is included, and more preferably a methoxycarbonyl group is included. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group.

[0117] From the viewpoint that the production of the monomer leading to the structural unit (a6) is easy, a sultone ring having no substituent is preferable. As the sultone ring, a ring represented by the following formula (T1’) is preferable. TIFF2025100428000079.tif2665[In the formula (T1’), X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents any integer from 0 to 9. When ma is 2 or more, a plurality of R 41 may be the same or different. The bonding site is at an arbitrary position.] X 11 is preferably an oxygen atom or a methylene group, more preferably a methylene group. R 41 Examples thereof are the same as those of the substituent of the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group is preferable. ma is preferably 0 or 1, more preferably 0.

[0118] Examples of the ring represented by the formula (T1’) include the following rings. The bonding site is at an arbitrary position. Among them, those in which the bonding site is at the 1-position or the 3-position are preferable. TIFF2025100428000080.tif44147

[0119] The structural unit having a -SO2- group preferably further has a group derived from a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, a methacryloylthio group and the like. Among them, the monomer leading to the structural unit (a6) is preferably a monomer having an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer.

[0120] The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2025100428000081.tif3878[In the formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. A xx represents an oxygen atom, -N(R c )- or a sulfur atom. A x represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -CO- or -N(R d )-. X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents the same meaning as described above. ma represents any integer from 0 to 9. When ma is 2 or more, a plurality of R 41 may be the same or different. R c and R d each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.]

[0121] R x Examples of the halogen atom of R include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R x Examples of the alkyl group of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group and an n-hexyl group, etc., preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group. R xExamples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, a triiodomethyl group, and the like. R x is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0122] A x Examples of the divalent saturated hydrocarbon group of A include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and a combination of two or more of these groups may also be used. Specifically, linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, a heptadecane-1,17-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group; branched alkanediyl groups such as a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group; monocyclic divalent alicyclic saturated hydrocarbon groups which are cycloalkanediyl groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, and a cyclooctane-1,5-diyl group; Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, and the like. A x The bonding position to the sultone ring of x can be any position, but the position at the 1-position is preferred.

[0123] Examples of the structural unit (a6-0) include the following structural units. TIFF2025100428000082.tif78129

[0124] Among them, the structural units represented by formula (a6-1), formula (a6-2), formula (a6-6), formula (a6-7), formula (a6-8) and formula (a6-12) are preferred, and the structural units represented by formula (a6-1), formula (a6-2), formula (a6-7) and (a6-8) are more preferred. When the resin (A) has the structural unit (a6), its content is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, and still more preferably 3 to 30 mol% based on all the structural units of the resin (A).

[0125] <Structural unit (a7)> The resin (A) etc. may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"). Specific examples of the structural unit (a7) include the structural units described in JP-A-2016-79235, and it is preferably a structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain or a structural unit having a sulfonio group and an organic anion in the side chain.

[0126] The structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (a7-A). TIFF2025100428000083.tif26123[In formula (a7-A), all the symbols have the same meanings as described above.]

[0127] Ra7 The alkyl group having 1 to 6 carbon atoms in a7 includes a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a7 Examples of the halogen atom in a7 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a7 Examples of the alkyl group having 1 to 6 carbon atoms and having a halogen atom in a7 include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, and a dibromomethyl group. R a7 R is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0128] X a71 When X is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025100428000084.tif3351[In formula (X10), Ax represents a bonding species that binds to the carbon atom to which R a7 is bonded, and represents one or more bonding species selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. Ay is L a71Represents a bonding type that binds to, and represents one or more bonding types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond. Rx represents a halogen atom, a hydroxy group, a C1-C6 fluoroalkyl group, a C1-C18 alkyl group, or a C1-C6 alkoxy group. mx represents any integer from 0 to 4, and when mx is an integer of 2 or more, the plurality of Rx may be the same as or different from each other. When either Ax or Ay is a single bond, it is preferable that the other is one or more selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond. When either Ax or Ay is an amide bond, it is preferably a bond represented by -CO-NR a71 -. The bonding position of Ay in the phenylene group is preferably the m-position or the p-position with respect to the bonding position of Ax, and more preferably the p-position. Among them, Rx is preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, or an ethyl group. mx is preferably 0, 1, or 2. X a71 Examples of [X] include, for example, a single bond, the following formula (X 10 -1) to formula (X 10 -10). * represents the bonding site with the carbon atom to which -R a7 is bonded. ** represents the bonding site with L a71 . X 20 represents -O- or -NR a71 -. TIFF2025100428000085.tif43162 Formula (X 10 -1) to formula (X 10 -10) Specific examples of the groups represented by include the following groups. TIFF2025100428000086.tif78162 Among them, X 10 is a single bond or formula (X 10 -1') and formula (X 10 -3') to formula (X10 It is preferably a group represented by any of (-10’), and is a single bond or formula (X 10 -1’), formula (X 10 -4’), formula (X 10 -5’), formula (X 10 -6’) and formula (X 10 -10’), more preferably a single bond, a group represented by formula (X 10 -1’), a group represented by formula (X 10 -5’) or a group represented by formula (X 10 -6’).

[0129] L a71 Examples of the hydrocarbon group of are a group obtained by removing one hydrogen atom from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, and bonding to X a71 and X a72 . Further, examples of the hydrocarbon group of L a72 are a group obtained by removing one hydrogen atom from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, and bonding to X a72 and RA - . L a71 and L a72 Examples of the chain hydrocarbon group of include a group obtained by removing one hydrogen atom from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specifically includes a methane group, an ethane group, a propane group, an iso-propyl group, an n-butyl group, a sec-butyl group, an iso-butyl group, a tert-butyl group, a heptyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decane group, an undecane group, a dodecane group, a tridecane group, a tetradecane group, a pentadecane, a heptadecane group, etc. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, a nonenyl group. The number of carbon atoms in the chain hydrocarbon group is preferably from 1 to 36, more preferably from 1 to 20, and even more preferably from 1 to 10. L a71 and L a72 Examples of the alicyclic hydrocarbon group of L and L include a group obtained by removing one hydrogen atom from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cyclopentane group, a cyclohexane group, a cyclopentyl group, a cyclooctyl group, and the like. L a71 and L a72 Examples of the polycyclic cycloalkyl group of L and L include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include a norbornane group, an adamantane group, and the like. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4.4.0]decanyl group, a steroid group (steroid skeleton), and the like. Examples of the ring in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornane group, and an adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. Further, a double bond may be formed between two carbon atoms included in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group represented by the following formula can be given. TIFF2025100428000087.tif28158 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably from 3 to 12, more preferably from 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably from 7 to 12. L a71 and L a72Examples of the aromatic hydrocarbon group include aryl groups with one hydrogen atom removed. Examples of aryl groups include phenyl group, naphthyl group, anthryl group, biphenyl group, fluorene group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, and more preferably 5 to 10. L a71 and L a72 When -CH2- contained in the hydrocarbon group of a71 and a72 is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group. L a71 and L a72 Among the hydrocarbon groups of a71 and a72 , examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include hydroxy group, carboxy group, thiol group, carbonyl group, oxy group, thio group, sulfonyl group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, alkanedioxy group, alkanedioxycarbonyl group, alkanediylcarbonyl group, alkanediylcarbonyloxy group, etc. These replaced groups include those similar to the groups exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. L a71 and L a72 Among the hydrocarbon groups of a71 and a72 , examples of the group in which -CH2- contained in the alicyclic hydrocarbon group and the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include those similar to the ones exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. L a71 and L a72 Among the hydrocarbon groups of a71 and a72 , -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include furan ring or thiophene ring, respectively. L a71 and L a72Examples of a group formed by combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group include a group formed by combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, a group formed by combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, a group formed by combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and a group formed by combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group, and the above aromatic hydrocarbon group. Examples of the combined group include the above. As the group formed by combining the alicyclic hydrocarbon group and the aromatic hydrocarbon group, a condensed ring may be used. L a71 and L a72 Examples of the substituent that the hydrocarbon group of may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a71 and L a72 When and are a group formed by combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with a chain hydrocarbon group, the chain hydrocarbon group may be substantially regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, L b1‘ and L b2‘ When -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of and is replaced by -O-, -CO-, -S-, or -SO2-, the hydrocarbon group of and may substantially have substituents such as a hydroxy group, a carboxyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, and a sulfonyl group. b1‘ and L b2‘ na7 is preferably 0 or 1. ZA in the formula (a7-A) + is the same as the cation Z1 in the salt represented by the formula (B1) described later + and the like can be mentioned.

[0130] Examples of the structural unit represented by the formula (a7-A) include, for example, the following structural units, R a7 a7Groups corresponding to the methyl group are replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group, etc.), and structural units described in WO 2012 / 050015. ZA + represents an organic cation. TIFF2025100428000088.tif179164

[0131] TIFF2025100428000089.tif188157

[0132] The structural unit having a sulfonio group and an organic anion in the side chain is preferably a structural unit represented by the formula (a7-B). TIFF2025100428000090.tif27104[In the formula (a7-B), R a7 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A II1 represents a single bond or a divalent linking group. R II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. R II2 and R II3 each independently represent a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, and R II2 and R II3 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. A - represents an organic anion. ] R a7 Examples of the halogen atom and the alkyl group which may have a halogen atom of R include the same halogen atoms and alkyl groups which may have a halogen atom as those in the formula (a7-A). R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by include a phenylene group and a naphthylene group. R II2 and R II3Examples of the hydrocarbon group represented by include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group formed by combining these groups are the same as those described above. A II1 Examples of the divalent linking group represented by include a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S-, or -CO-. Examples of the divalent saturated hydrocarbon group include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, or a combination thereof. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Examples of those in which -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S-, or -CO- include divalent groups represented by formula (X1) to formula (X53). However, the number of carbon atoms before -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S-, or -CO- is 17 or less, respectively. In the following formulas, * and ** represent bonding sites, and * is RII2 represents the binding site with JPEG2025100428000091.jpg123161[wherein, X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.]

[0133] Examples of the structural unit containing the cation in formula (a7-B) include the structural unit represented below and a structural unit in which the group corresponding to the methyl group of R a7 is replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group, etc.). TIFF2025100428000092.tif75163

[0134] A - Examples of the organic anion represented by - include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, etc. The organic anion represented by

[0135] Examples of the structural unit represented by formula (a7-B) include the structural unit represented below. JPEG2025100428000093.jpg95156

[0136] When the resin (A) contains the structural unit (a7), the structural unit (a7) may be contained alone or may contain two or more kinds. The content rate of the total structural unit (a7) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and still more preferably 3 to 20 mol% based on all the structural units of the resin (A).

[0137] The resin (A) is preferably a resin composed of the structural unit (I), at least one selected from the group consisting of the structural units (a1-4) and (a1-6), the structural units (a2-A) and (a2-B); a resin composed of the structural unit (I), at least one selected from the group consisting of the structural units (a1-4) and (a1-6), the structural unit (a2-A), the structural unit (a2-B), and the structural unit (a7-A); a resin composed of the structural unit (I), at least one selected from the group consisting of the structural units (a1-4) and (a1-6), the structural unit (a2-A), and the structural unit (s); a resin composed of the structural unit (I), at least one selected from the group consisting of the structural units (a1-4) and (a1-6), the structural unit (a2-A), and at least one selected from the group consisting of the structural units (a1-0), (a1-1), and (a1-2); a resin composed of the structural unit (I), at least one selected from the group consisting of the structural units (a1-4) and (a1-6), the structural unit (a2-A), at least one selected from the group consisting of the structural units (a1-0), (a1-1), and (a1-2), and at least one selected from the group consisting of the structural unit (s). The structural unit (s) is preferably at least one selected from the group consisting of the structural units (a2) and (a3). The structural unit (a2) is preferably the structural unit (a2-1), the structural unit (a2-A), or the structural unit (a2-B). The structural unit (a3) is preferably at least one selected from the group consisting of the structural unit represented by the formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-4).

[0138] Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers that lead to these structural units. The content ratio of each structural unit of the resin (A) can be adjusted by the amount of monomers used in the polymerization. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less), but may contain oligomers having a weight average molecular weight smaller than this. In this specification, the weight average molecular weight is a value determined under the conditions described in the examples by gel permeation chromatography.

[0139] [[Resist composition]] The resist composition of the present invention is a resist composition containing the resin (A). The resist composition of the present invention preferably further contains an acid generator. In addition to the resin (A), the resist composition of the present invention may contain, unlike the resin (A), a resin containing a structural unit having an acid-labile group without containing the structural unit (I) (hereinafter sometimes referred to as "resin (A2)"), a resin other than the resin (A) and the resin (A2), and an acid generator (hereinafter sometimes referred to as "acid generator (B)"). Examples of the acid generator include acid generators known in the resist field (hereinafter sometimes referred to as "acid generator (B)") and / or solvents (hereinafter sometimes referred to as "solvent (E)"). The resist composition of the present invention preferably further contains a quencher (hereinafter sometimes referred to as "quencher (C)") and / or a solvent (hereinafter sometimes referred to as "solvent (E)").

[0140] [[Resin (A2)]] Resin (A2) has a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit having an acid-labile group including the structural unit represented by formula (a1-2) (hereinafter sometimes referred to as "structural unit (a1)"). The structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)"). Resin (A2) preferably further contains a structural unit other than the structural unit (a1). Examples of the structural unit other than the structural unit (a1) include the above-described structural unit (s) and the above-described other structural units.

[0141] When resin (A2) contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is usually 10 to 95 mol%, preferably 15 to 90 mol%, and more preferably 20 to 85 mol% based on all the structural units of resin (A2). When resin (A2) contains the structural unit (a1-3), its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, and even more preferably 20 to 85 mol% based on all the structural units of resin (A2). When resin (A2) has the structural unit (a1-4), its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, and even more preferably 20 to 85 mol% based on all the structural units of resin (A2). When resin (A2) has the structural unit (a1-5), its content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, and even more preferably 5 to 40 mol% based on all the structural units of resin (A2).

[0142] As the structural unit (a1) having an acid-labile group in the resin (A2), at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2), and the structural unit (a1-5) is preferable, at least two or more are more preferable, and the combination of the structural unit (a1-1) and the structural unit (a1-2), the combination of the structural unit (a1-1) and the structural unit (a1-5), the combination of the structural unit (a1-1) and the structural unit (a1-0), the combination of the structural unit (a1-2) and the structural unit (a1-0), the combination of the structural unit (a1-5) and the structural unit (a1-0), the combination of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2), and the combination of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-5) are more preferable, and the structural unit (a1-1) or the structural unit (a1-2), and the combination of the structural unit (a1-1) and the structural unit (a1-2) are particularly preferable.

[0143] When the resin (A2) has the structural unit (a2-0), its content is preferably 5 to 95 mol%, more preferably 10 to 80 mol%, and even more preferably 15 to 80 mol% with respect to all the structural units of the resin (A2). When the resin (A2) contains the structural unit (a2-1), its content is usually 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, and even more preferably 2 to 20 mol% with respect to all the structural units of the resin (A2).

[0144] When the resin (A2) contains the structural unit (a3), its total content is usually 5 to 70 mol%, preferably 10 to 65 mol%, and more preferably 10 to 60 mol% with respect to all the structural units of the resin (A2). Also, the content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3), and the structural unit (a3-4) is preferably 5 to 60 mol%, more preferably 5 to 50 mol%, and even more preferably 10 to 50 mol% with respect to all the structural units of the resin (A2), respectively.

[0145] When the resin (A2) has the structural unit (a4), its content is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and still more preferably 3 to 10 mol% based on all the structural units of the resin (A2). When the resin (A2) has the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and still more preferably 3 to 15 mol% based on all the structural units of the resin (A2). When the resin (A2) contains the structural unit (a6), its content is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, and still more preferably 3 to 30 mol% based on all the structural units of the resin (A). When the resin (A2) contains the structural unit (a7), its content is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and still more preferably 3 to 20 mol% based on all the structural units of the resin (A2).

[0146] The resin (A2) is preferably a resin composed of the structural unit (a1) and the structural unit (s), that is, a copolymer of the monomer (a1) and the monomer (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group), more preferably at least two kinds, and still more preferably at least two kinds selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably the structural unit (a2-1) or the structural unit (a2-A). The structural unit (a3) is preferably at least one selected from the group consisting of the structural unit represented by the formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-4).

[0147] Each structural unit constituting the resin (A2) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers that induce these structural units. The content of each structural unit of the resin (A2) can be adjusted by the amount of monomers used in the polymerization. The weight average molecular weight of the resin (A2) is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more), 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less), but may contain oligomers having a weight average molecular weight smaller than this.

[0148] <Resins other than resin (A) and resin (A2)> The resist composition of the present invention may contain a resin other than the resin (A) and the resin (A2). Examples of the resin other than the resin (A) and the resin (A2) include resins composed of only structural unit(s), resins composed of structural unit (a2), structural unit (a3) and / or structural units derived from other known monomers.

[0149] Also, as other resins, resins containing structural unit (a4) and / or structural unit (a5) (however, not containing structural unit (I) and structural unit (a1); hereinafter sometimes referred to as "resin (X)") etc. are also included. Among them, as the resin (X), a resin containing structural unit (a4) is preferable. When the resin (X) contains the structural unit (a4), in the resin (X), the content of the structural unit (a4) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, still more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. When the resin (X) contains the structural unit (a5), the content of the structural unit (a5) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, still more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. Further, when the resin (X) contains the structural unit (a4) and the structural unit (a5), the total content of the structural unit (a4) and the structural unit (a5) is 40 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, and still more preferably 80 mol% or more, based on the total of all the structural units of the resin (X). Furthermore, it is 100 mol% or less. Specifically, it is 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and still more preferably 80 to 100 mol%. Examples of the structural unit that the resin (X) may further have include the structural unit (a2), the structural unit (a3), and the structural unit derived from other known monomers. Among them, the resin (X) is preferably a resin composed of only the structural unit (a4) and / or the structural unit (a5). Each structural unit constituting the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers that induce these structural units. The content of each structural unit of the resin (X) can be adjusted by the amount of monomers used in the polymerization. The weight average molecular weight of the resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less), but may contain oligomers having a weight average molecular weight smaller than this. The measuring means for the weight average molecular weight of the resin (X) is the same as that of the resin (A2).

[0150] When the resist composition of the present invention contains the resin (X), its content is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, still more preferably 1 to 40 parts by mass, even more preferably 1 to 30 parts by mass, and even more preferably 1 to 8 parts by mass with respect to 100 parts by mass of the total content of the resin (A) and the resin (A2).

[0151] The content of the resin (A) in the resist composition is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less with respect to the solid content of the resist composition. The total content of the resin (A) and the resin (A2) in the resist composition is preferably 20% by mass or more and 100% by mass or less, more preferably 50% by mass or more and 99% by mass or less with respect to the solid content of the resist composition. When including resins other than the resin (A) and the resin (A2), the total content of the resin (A), the resin (A2), and the resins other than the resin (A) and the resin (A2) is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less with respect to the solid content of the resist composition. The solid content of the resist composition and the content of the resin relative thereto can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0152] <Acid generator (B)> As the acid generator (B), either a nonionic compound or an ionic compound may be used. Examples of the nonionic compound include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxy ketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), and the like. Representative examples of the ionic compound include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of the anion of the onium salt include sulfonic acid anion, benzenesulfonyl anion, sulfonylimide anion, sulfonylmethide anion, and carboxylic acid anion, among others. The acid generator (B) may be one of the structural units constituting the resin contained in the resist composition of the present invention, such as the structural unit (a7).

[0153] As the acid generator (B), compounds that generate an acid upon irradiation, as described in, for example, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc., can be used. Further, compounds produced by known methods may also be used. The acid generator (B) may be an acid generator having an acid-labile group. For example, the compound or resin serving as the acid generator may contain a partial structure that becomes an acid-labile group, and the acid-labile group preferably contains the above-described group (1) or group (2). When the resist composition of the present invention has a compound having an acid-labile group, the resin containing a structural unit having an acid-labile group may not be included.

[0154] A preferred form of the acid generator (B) includes a salt represented by the formula (B1) (hereinafter sometimes referred to as "acid generator (B1)"). TIFF2025100428000094.tif1392[wherein all the symbols are the same as those described above.] The number of carbon atoms in the hydrocarbon group is preferably from 1 to 48, more preferably from 1 to 42, still more preferably from 1 to 36, even more preferably from 1 to 30, and even more preferably from 1 to 24. Examples of the chain hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, heptadecyl group and the like. Examples of the alkenyl group include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, isooctenyl group, nonenyl group. The number of carbon atoms in the chain hydrocarbon group is preferably from 1 to 36, more preferably from 1 to 24, still more preferably from 1 to 20, even more preferably from 1 to 18, even more preferably from 1 to 12, and even more preferably from 1 to 10. Examples of the alicyclic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include a norbornyl group and an adamantyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of the cycloalkyl group in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. Further, a double bond may be formed between two carbon atoms included in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group represented by the following formula can be given. TIFF2025100428000095.tif26168 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, still more preferably 3 to 18, even more preferably 3 to 12, even still more preferably 3 to 10, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms of the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, still more preferably 6 to 18, even more preferably 6 to 12, and even still more preferably 7 to 12. Examples of the aromatic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a fluorenyl group. More specifically, examples of the aromatic hydrocarbon group represented by the following formula can be given. For the number of carbon atoms in the aromatic hydrocarbon group in TIFF2025100428000096.tif1085, it is preferably 4 to 24, more preferably 4 to 20, still more preferably 4 to 18, even more preferably 5 to 14, still even more preferably 5 to 10, and even more preferably 6 to 10. L b1 When -CH2- contained in the hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is taken as the number of carbon atoms of the hydrocarbon group. L b1Among the hydrocarbon groups, examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a thiol group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-O-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanedioyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanedioyl group is replaced by -O-CO-), an alkanedioylcarbonyl group (a group in which -CH2- at any position contained in an alkanedioyl group is replaced by -CO-), an alkanedioylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanedioyl group is replaced by -CO-O-), etc., an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -S-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is-SO2-, etc.). These substituted groups include the same groups as those described above, within the range permitted by the upper limit of the number of carbon atoms. L b1 Among the hydrocarbon groups of b1 , examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include groups containing structures such as cyclic ethers, cyclic ketones, cyclic esters (lactones), cyclic thioethers, cyclic acetals, cyclic sulfonic acid esters (sultones), etc. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding position of the alicyclic hydrocarbon group mentioned in the following formulas can be any position. TIFF2025100428000097.tif48165L b1 Among the hydrocarbon groups of b1 , -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively. Specifically, aromatic hydrocarbon groups represented by the following formulas can be mentioned. TIFF2025100428000098.tif1324L b1 Among the hydrocarbon groups of b1 , -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include a furan ring or a thiophene ring, respectively. Examples of the group in which -CH2- contained in the group combining an alicyclic saturated hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. Examples of a group formed by combining two or more of an alicyclic hydrocarbon group, an aliphatic hydrocarbon group, and an aromatic hydrocarbon group include a group formed by combining the above aliphatic hydrocarbon group and the above alicyclic hydrocarbon group, a group formed by combining the above aliphatic hydrocarbon group and the above aromatic hydrocarbon group, a group formed by combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and a group formed by combining the above aliphatic hydrocarbon group, the above alicyclic hydrocarbon group, and the above aromatic hydrocarbon group. The above combined groups are included. The group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group may be a condensed ring. L b2 Examples of the divalent hydrocarbon group of include a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group formed by removing one hydrogen atom from a combination of two or more of these groups, which binds to Y b1 and the like. L b2 Examples of the divalent aliphatic hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group formed by combining two or more of these groups of L b1 are each a group formed by removing one hydrogen atom from the aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and group formed by combining two or more of these groups exemplified in L L b1 and L b2 Examples of the substituent that the hydrocarbon group of and L L b1 and L b2 may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. b1 and L b2 When and L b1 and L b2The hydrocarbon group may substantially have substituents such as a hydroxy group, a carboxyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, a sulfonyl group and the like. L b1 and L b2 The number of substituents that may be possessed is not particularly limited, and a plurality of substituents may be possessed. Y b1 Examples of the cyclic hydrocarbon group of Y include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of Y are respectively the same as the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified by L b1 and, when having no substituent, may be a monovalent alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 Examples of the substituents that the methyl group of Y may have include a halogen atom, a cyano group, a hydroxy group, and a nitro group. Y b1 Examples of the substituents that the cyclic hydrocarbon group of Y may have include a halogen atom, a cyano group, a nitro group, or a hydrocarbon group having 1 to 18 carbon atoms that may have a halogen atom, a cyano group, and a nitro group. -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y may have as a substituent include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these groups. Examples of the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group combining two or more of these groups include, within the range allowed by the upper limit of the number of carbon atoms, L b1 the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group similar to a group combining two or more of these groups exemplified by L. Also, Y b1Examples of groups in which -CH2- contained in a hydrocarbon group having 1 to 18 carbon atoms which may have a cyclic hydrocarbon group as a substituent is replaced by -O-, -S-, -CO- or -SO2- include, within the range allowed by the upper limit of the number of carbon atoms, groups similar to those exemplified by groups in which -CH2- contained in the hydrocarbon group of Lb1 is replaced by -O-, -S-, -CO- or -SO2-. Also, Y b1 The hydrocarbon group having 1 to 18 carbon atoms which may have a cyclic hydrocarbon group as a substituent may constitute a protecting group or a leaving group (an acid-labile group or a base-labile group) generally used in the art. The anion of the salt represented by formula (B1) is preferably an anion represented by the following formula (B1-A1) or an anion represented by formula (B1-A2). TIFF2025100428000099.tif31125[In formula (B1-A1), L b2 and Y b1 have the same meanings as in formula (B1). Q b1 Q b2 Q b3 and Q b4 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms. z1 represents any integer from 0 to 6. When z1 is 2 or more, the groups within the plurality of parentheses may be the same as or different from each other. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L b3 represents a single bond or an (nb2 + 1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. nb2 represents any integer from 1 to 3. When nb2 is 2 or more, the groups within the plurality of parentheses may be the same as or different from each other.] Q b1 Q b2 Q b3 and Q b4Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, and the like. Q b1 , Q b2 , Q b3 and Q b4 Examples of the perfluoroalkyl group of b4 include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, and the like. Q b1 and Q b2 are preferably included in at least one of b2 and b1 and Q, more preferably a fluorine atom or a perfluoroalkyl group, even more preferably a fluorine atom or a trifluoromethyl group, and even more preferably both are fluorine atoms. b1 and Q b2 b2 and b3 and Q are each independently preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, b3 is preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and b4 is preferably a hydrogen atom or a fluorine atom. Q b3 and Q b4 b4 and b3 and Q are each independently preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, b3 is preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and b4 is preferably a hydrogen atom or a fluorine atom. b3 b3 and b4 and Q are each independently preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, b3 is preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and b4 is preferably a hydrogen atom or a fluorine atom. b4 b4 is preferably a hydrogen atom or a fluorine atom. z1 is preferably any integer from 0 to 3, more preferably 0, 1 or 2. X 1 1 is preferably -O-CO- or -CO-O-.

[0155] L b3 Examples of the hydrocarbon group in b3 include the same hydrocarbon groups as those exemplified for L in formula (B1) within the range allowed by the upper limit of the number of carbon atoms. b1 b1 and b3 and Q are each independently preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, b3 is preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and b4 is preferably a hydrogen atom or a fluorine atom. In formula (B1-A1), L b3is a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), an optionally substituted aromatic hydrocarbon group having 6 to 10 carbon atoms (wherein -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-), or a group formed by combining two or more of these groups, preferably a single bond, a chain hydrocarbon group having 1 to 6 carbon atoms or a group represented by the following formula (Lb3-1). When -CH2- contained in the chain hydrocarbon group is replaced by -O- or -CO-, the number thereof is preferably 1 to 4, and preferably one -CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO- or -CO-O-, or one -CH2-CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO-O-. TIFF2025100428000100.tif1582[In the formula (Lb3-1), nb2 represents the same meaning as the formula (B1-A1). L b31 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent. W b3 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent. * and ** represent bonding sites, and * represents the bonding site with X 1 and represents the bonding site with.] In the formula (Lb3-1), L b31 's chain hydrocarbon group, as long as the upper limit of the number of carbon atoms permits, L b1Examples thereof include the same groups as the chain hydrocarbon groups exemplified above. In formula (Lb3-1), W b3 The alicyclic hydrocarbon group and aromatic hydrocarbon group of, as long as the upper limit of the number of carbon atoms permits, are the same groups as the alicyclic hydrocarbon groups and aromatic hydrocarbon groups exemplified by L b1 Examples thereof include the same groups as the alicyclic hydrocarbon groups and aromatic hydrocarbon groups exemplified above. In formula (Lb3-1), L b31 The substituents that the chain hydrocarbon group of may have and W b3 The substituents that the alicyclic hydrocarbon group and aromatic hydrocarbon group of may have are the same groups as the substituents exemplified as the substituents that the hydrocarbon group of L b1 may have. L b31 is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, as the alicyclic hydrocarbon group and aromatic hydrocarbon group of W b3 the following alicyclic hydrocarbon groups and aromatic hydrocarbon groups are preferred. In the alicyclic hydrocarbon groups and aromatic hydrocarbon groups represented below, * and ** represent bonding sites, * represents the bonding site with X 1 or L b31 and ** represents a hydrogen atom, a substituent or the bonding site with L b2 and at least one ** represents the bonding site with L b2 In addition, in the alicyclic hydrocarbon groups represented below, the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. When the -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, it is preferably a ether ring, an ester ring (lactone), a carbonate ester ring, a sulfonic acid ester ring ( sultone) or an acetal ring. In formula (B1-A1), L b2is preferably a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and is a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O- or *-L b21 -X 2 -L b22 -**(L b21 and L b22 either represents a chain hydrocarbon group having 1 to 6 carbon atoms, and the other represents a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms. X 2 represents -O-, -CO-O-, -O-CO- or -O-CO-O-. * and ** represent bonding sites, and ** represents the bonding site with Y b1 However, L b21 X 2 and L b22 The total number of carbon atoms of is 12 or less.). It is more preferable that In formula (B1-A1), Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and still more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, it is preferably a group represented by the following formula (Y1) to formula (Y36). In formula (Y1) to formula (Y36), R Yb represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms among the substituents that the cyclic hydrocarbon group of Y b1 may have, and R Yc represents a hydrogen atom or a substituent that the cyclic hydrocarbon group of Y b1 may have, and * represents L b2represents a binding site to. The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formula are not particularly illustrated in the following formula, but may have substituents that the cyclic hydrocarbon group of Y b1 may also have. TIFF2025100428000102.tif83159

[0156] As the anion in the salt represented by the formula (B1), anions represented by the formulas (B1-A1-1) to (B1-A1-85) [hereinafter, may be referred to as "anion (B1-A1-1)" etc. according to the formula number] are preferable, and an anion represented by any of the formulas (B1-A1-1) to (B1-A1-4), formula (B1-A1-9), formula (B1-A1-10), formulas (B1-A1-24) to (B1-A1-33), formulas (B1-A1-36) to (B1-A1-40), and formulas (B1-A1-47) to (B1-A1-85) is more preferable. TIFF2025100428000103.tif215160

[0157] TIFF2025100428000104.tif251151

[0158] TIFF2025100428000105.tif254163

[0159] Here, R i2 ~R i7 are, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 represent the same meaning as above. Examples of the anion represented by the formula (B1-A1) specifically include the anions described in JP-A-2010-204646.

[0160] Examples of the anion in the preferably formed salt represented by the formula (B1) include anions represented by the formulae (B1a-1) to (B1a-70). TIFF2025100428000106.tif185163

[0161] TIFF2025100428000107.tif252166

[0162] TIFF2025100428000108.tif69166

[0163] Among them, anions represented by any of the formulae (B1a-1) to (B1a-3), (B1a-7) to (B1a-19), and (B1a-22) to (B1a-70) are preferred.

[0164] The anion represented by the formula (B1-A2) is represented by the following formula. TIFF2025100428000109.tif23100[In the formula (B1-A2), L b2 and Y b1 have the same meanings as in the formula (B1). R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl group may be replaced by -O- or -CO-. nb4 represents any integer from 1 to 5. When nb4 is 2 or more, a plurality of -L b2 -Y b1 may be the same as or different from each other. nb3 represents any integer from 0 to 4. When nb3 is 2 or more, a plurality of R b1 may be the same as or different from each other. However, 1 ≦ nb4 + nb3 ≦ 5 is satisfied.]

[0165] In formula (B1-A2), L b2 Examples of the hydrocarbon group of and Y b1 Examples of the cyclic hydrocarbon group of are, within the range permitted by the upper limit of the number of carbon atoms, the same as the examples of the hydrocarbon group of L in formula (B1) b2 Examples of the hydrocarbon group of and Y b1 Examples of the cyclic hydrocarbon group of are the same as those given. The hydrocarbon group of L b2 , the methyl group of Y b1 and the substituents that the cyclic hydrocarbon group may have are also the same as the examples of the hydrocarbon group of L in formula (B1) b2 , the methyl group of Y b1 and the substituents that the cyclic hydrocarbon group may have. L b2 preferably represents an alkanediyl group having 1 to 12 carbon atoms, and the -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. More preferably, *-CO-O-L b41 -(L b41 is a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms, and the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. * represents the bonding site with the phenyl group to which SO3 - is bonded. L b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms. ). Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have substituents (the -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-). More preferably, it is an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have substituents (the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have substituents. Even more preferably, Y in formula (B1-A1) b1 or L b1 is the alicyclic hydrocarbon group or aromatic hydrocarbon group exemplified by. Specifically, it is preferably a group represented by the above-mentioned formulas (Y1) to (Y36), and more preferably a group represented by the above-mentioned formulas (Y1) to (Y19).

[0166] In formula (B1-A2), nb4 is preferably any integer from 1 to 4, more preferably any integer from 1 to 3, still more preferably 1 or 2, and even more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 The bonding position of is preferably the following structure which is the m-position substitution of the benzene ring with respect to the bonding position of SO3 - . TIFF2025100428000110.tif29107[In the above formula, L b2 , Y b1 , R b1 , and nb3 have the same meanings as in formula (B1-A2).] In formula (B1-A2), when nb4 is 2 or more, the plurality of L b2 and Y b1 preferably represent the same group as each other.

[0167] R b1 Examples of the alkyl group having 1 to 6 carbon atoms for R include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, and hexyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R b1 Examples of the halogen atom for R include fluorine atom, chlorine atom, bromine atom, and iodine atom. R b1 is each independently preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), more preferably a fluorine atom, an iodine atom, or an alkyl group having 1 to 3 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), and still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group, or a methyl group. nb3 is an integer from 0 to 4 (that is, nb3 - 1 represents an integer from 0 to 3), preferably an integer from 0 to 3, and more preferably an integer from 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, R b1 is preferably a halogen atom, and R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2, one of R b1 is preferably a halogen atom and the other is preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms, and one of R b1 is more preferably a fluorine atom or an iodine atom and the other is more preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 3 carbon atoms.

[0168] Examples of the anion (B1 - A2) include the following anions. Among them, anions represented by formula (B2a - 1) to formula (B2a - 20) are preferred, and anions represented by formula (B2a - 1) to formula (B2a - 11), formula (B2a - 16) to formula (B2a - 20) are more preferred. In the following anions, some R b1 are omitted and may include substituents not shown. TIFF2025100428000111.tif95162

[0169] In another form of the acid generator (B), an anion in which the anion represented by formula (B1) is replaced with a sulfonimide anion, a sulfonylmethide anion or a carboxylic acid anion is also preferably used as the acid generator (B). Sulfonylimide anions and sulfonylmethide anions are represented by the following formulas. TIFF2025100428000112.tif1189[In formula (B1 - A3), A 1 represents a nitrogen atom or a carbon atom. L b2' represents a hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 ' represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. nb5 represents 2 or 3. A 1 When A is a nitrogen atom, nb5 is 2, and A 1 When A is a carbon atom, nb5 is 3. A plurality of -L b2 '-Y b1 ' may be the same as or different from each other, and two -SO2-L b2 '-Y b1 ' may combine together to form a ring.

[0170] In formula (B1-A3), examples of the hydrocarbon group, cyclic hydrocarbon group and their substituents of L b2’ and Y b1’ are the same groups as those of L b2 and Y b1 in formula (B1-A1). L b2 ' is a single bond, *-L b23 -X 2 - or *-L b23 -X 2 -W 2 -X 3 -(L b23 represents an alkanediyl group having 1 to 6 carbon atoms which may have a fluorine atom, X 2 and X 3 each independently represent -O-, -CO-O-, -O-CO-, -O-CO-O- or -O-, W 2 represents an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-, and * represents the bonding site with SO2.). It is preferably this. Y b1' is preferably a trifluoromethyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or a phenyl group which may have a substituent, and more preferably a trifluoromethyl group or a group represented by Formula (Y1) to Formula (Y36) in Formula (B1-A1). In Formula (B1-A3), two SO2-L b2 '-Y b1 When'-Y' combines together to form a ring, for example, an anion represented by Formula (B1-A3') can be mentioned. TIFF2025100428000113.tif21122[In Formula (B1-A3'), A 1 、Y b1 、L b2 、nb5 represent the same meanings as in Formula (B1) and Formula (B1-A3). W b4 represents a disulfonylimide ring or a disulfonylmethide ring having 3 to 12 carbon atoms which may have a fluorine atom. W b4 The disulfonylimide ring or the disulfonylmethide ring of W preferably has 3 to 6 carbon atoms, and the hydrogen atom of the methylene group contained in the ring is preferably replaced by a fluorine atom.

[0171] Examples of the anion represented by Formula (B1-A3) include the following. Among them, anions represented by Formula (B3a-1) and Formula (B3a-2) are preferable. TIFF2025100428000114.tif132161

[0172] TIFF2025100428000115.tif57165

[0173] Examples of the carboxylic acid anion include the following. TIFF2025100428000116.tif41155

[0174] Z1 +Examples of the organic cation include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, organic phosphonium cations, and the like. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations or aryliodonium cations are more preferred. Specifically, cations represented by any of Formula (b2-1) to Formula (b2-5) (hereinafter sometimes referred to as "cation (b2-1)" etc. according to the formula number) can be mentioned. TIFF2025100428000117.tif83159[In Formula (b2-1) to Formula (b2-5), R b4 ~R b6 each independently represents a linear hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the linear hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group. The hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S-, or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of 0 to 5. When m2 is 2 or more, a plurality of Rb7 may be the same or different, and when n2 is 2 or more, a plurality of Rs b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may combine with each other to form a ring together with the sulfur atom to which they are attached, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the chain hydrocarbon group may be substituted by an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted by an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may combine with each other to form a ring including the -CH-CO- to which they are attached, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 and R b21 ~R b26 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. R b13 and R b14 and R b21 and R b22 may combine with each other to form a ring containing a sulfur atom together with the benzene ring to which they are attached, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b27 ~R b29 each independently represents a hydrogen atom or a group containing an acid-labile group. L b31 and L b41 ~L b43 each independently represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of any one of 0 to 5. q2 and r2 each independently represent an integer of any one of 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, a plurality of R b13 are the same or different, when p2 is 2 or more, a plurality of R b14 are the same or different, when q2 is 2 or more, a plurality of R b15 are the same or different, when r2 is 2 or more, a plurality of R b16 are the same or different, when s2 is 2 or more, a plurality of R b17 are the same or different, when t2 is 2 or more, a plurality of R b18 are the same or different. u3 represents an integer of any one of 1 to 3, and satisfies 1 ≦ u3 + q23 ≦ 5. u4 and u5 each independently represent an integer of any one of 0 to 3, and satisfy 0 ≦ u4 + o21 ≦ 5 and 0 ≦ u5 + p22 ≦ 5. o21, p22, q23, r24, t25, and s26 each independently represent an integer of any one of 0 to 4. When u3, u4, and u5 are each 2 or more, the groups in parentheses are each the same or different. When o21, p22, q23, r24, t25, and s26 are each 2 or more, a plurality of R b21 ~R b26 are each the same or different. When u3, u4, and u5 are each 2 or more, the groups in parentheses are each the same or different. When u2 is 0, any one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16At least one of them is preferably a halogen atom. When u2 is 1, any one of o2, p2, s2, t2, q2 and r2 is 1 or more, and R b13 ~R b18 At least one of them is preferably a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, and more preferably 1. Also, when u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom.

[0175] The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. In particular, the chain hydrocarbon group of R b9 ~R b12 is preferably having 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups. TIFF2025100428000118.tif11157 In particular, the alicyclic hydrocarbon group of R b9 ~R b12 is preferably having 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

[0176] Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methylnorbornil group, an isobornyl group, and the like. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The alkyl fluoride group represents an alkyl group having 1 to 12 carbon atoms and having a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a perfluorobutyl group. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4.

[0177] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples of the aromatic hydrocarbon group having a chain hydrocarbon group include a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group, and examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group include a p-cyclohexylphenyl group and a p-adamantylphenyl group. When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferable. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.

[0178] Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, a dodecyloxy group, and the like. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, a 2-ethylhexylcarbonyloxy group, and the like.

[0179] R b4 and R b5 The ring formed by R and R bonding to each other together with the sulfur atom to which they are bonded may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated, and unsaturated rings. Examples of this ring include rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. In addition, examples of the ring containing a sulfur atom include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, the following rings can be mentioned. * represents the bonding site. TIFF2025100428000119.tif23142

[0180] R b9 and R b10 The ring formed by R and R together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated, and unsaturated rings. Examples of this ring include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, a 1,4-oxathian-4-ium ring, and the like can be mentioned. R b11 and R b12The ring formed by combining them may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring, etc. R b27 ~R b29 Examples of the group containing an acid-labile group of ~R c30 include -R c30 , -CO-O-R c10 or -L c30 -CO-O-R c10 (where L c30 represents an alkanediyl group having 1 to 6 carbon atoms, and R R b27 ~R b29 represents an acid-labile group. Examples include, etc.).

[0181] Among cations (b2-1) to (b2-5), preferably, cation (b2-1), cation (b2-4) or cation (b2-5). Examples of cation (b2-1) include the following cations. TIFF2025100428000120.tif149164 Examples of cation (b2-2) include the following cations. TIFF2025100428000121.tif15135 Examples of cation (b2-3) include the following cations. TIFF2025100428000122.tif21130 Examples of cation (b2-4) include the following cations. TIFF2025100428000123.tif123164 Examples of cation (b2-5) include the following cations. TIFF2025100428000124.tif115157

[0182] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. As the acid generator (B), preferably, it is any of the anions represented by any of Formula (B1a-1) to Formula (B1a-3), Formula (B1a-7) to Formula (B1a-19), Formula (B1a-22) to Formula (B1a-70) or Formula (B2a-1) to Formula (B2a-11), Formula (B2a-16) to Formula (B2a-20), Formula (B1-3a-1) to Formula (B1-3a-3) or Formula (B1-3a-11) to Formula (B1-3a-14), and a combination with cation (b2-1), cation (b2-2), cation (b2-3), cation (b2-4) or cation (b2-5).

[0183] As the acid generator (B), preferably, those represented by Formula (B1-1) to Formula (B1-105), Formula (B2-1) to Formula (B2-20) and Formula (B3-1) to Formula (B3-28) are exemplified. Among them, those containing an arylsulfonium cation are preferred, and those represented by Formula (B1-1) to Formula (B1-3), Formula (B1-5) to Formula (B1-7), Formula (B1-11) to Formula (B1-14), Formula (B1-20) to Formula (B1-26), Formula (B1-29), Formula (B1-31) to Formula (B1-105), Formula (B2-1) to Formula (B2-20) and Formula (B3-1) to Formula (B3-28) are particularly preferred. TIFF2025100428000125.tif173168

[0184] TIFF2025100428000126.tif254162

[0185] TIFF2025100428000127.tif254165

[0186] TIFF2025100428000128.tif254159

[0187] TIFF2025100428000129.tif248162

[0188] TIFF2025100428000130.tif250150

[0189] TIFF2025100428000131.tif187159

[0190] The content rate of the acid generator (B1) is preferably 30 mass% or more and 100 mass% or less, more preferably 50 mass% or more and 100 mass% or less, and even more preferably substantially only the acid generator (B1), with respect to the total amount of the acid generator (B). The content rate of the acid generator (B) is preferably 1 mass% or more (more preferably 3 mass% or more) and preferably 30 mass% or less (more preferably 25 mass% or less) with respect to the solid content of the resist composition. Also, the content of the acid generator (B) is preferably 1 mass part or more (more preferably 3 mass parts or more) and preferably 30 mass parts or less (more preferably 25 mass parts or less) with respect to 100 mass parts of the resin (A2). The resist composition of the present invention may contain one kind of the acid generator (B) alone or may contain a plurality of kinds.

[0191] <Solvent (E)> The content rate of the solvent (E) in the resist composition is usually 90 mass% or more and 99.9 mass% or less, preferably 92 mass% or more and 99 mass% or less, and more preferably 94 mass% or more and 99 mass% or less. The content rate of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography. Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; and the like. One kind of the solvent (E) may be used alone, or two or more kinds may be used.

[0192] <Quencher (C)> Examples of the quencher (C) include salts that generate an acid with a lower acidity than the acid generated from the acid generator (B), and basic nitrogen-containing organic compounds. The content of the quencher (C) is preferably about 0.01 to 15% by mass, more preferably about 0.01 to 10% by mass, still more preferably about 0.1 to 8% by mass, and even more preferably about 0.1 to 7% by mass, based on the solid content of the resist composition.

[0193] The acidity of the salt that generates an acid with a lower acidity than the acid generated from the acid generator is indicated by the acid dissociation constant (pKa). The salt that generates an acid with a lower acidity than the acid generated from the acid generator is a salt in which the acid dissociation constant of the acid generated from the salt is usually -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. As the salt that generates an acid with a lower acidity than the acid generated from the acid generator, preferably, it is a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (a salt having a carboxylic acid anion), more preferably, it is the weak acid inner salt (D), and still more preferably, among the weak acid inner salts (D), it is a diphenyliodonium salt containing a phenyl group substituted with a carboxylic acid anion. TIFF2025100428000132.tif97153

[0194] As the weak acid inner salt (D), a diphenyliodonium salt having an iodonium cation to which two phenyl groups are bonded and a carboxylate anion substituted for at least one of the two phenyl groups bonded to the iodonium cation is preferable, and examples thereof include salts represented by the following formula. TIFF2025100428000133.tif1692[In formula (D), R D1 and R D2 each independently represent a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 7 carbon atoms, an acyloxy group having 2 to 7 carbon atoms, an alkoxycarbonyl group having 2 to 7 carbon atoms, a nitro group, or a halogen atom. m' and n' each independently represent an integer of 0 to 4. When m' is 2 or more, a plurality of R D1 may be the same or different, and when n' is 2 or more, a plurality of R D2 may be the same or different.] R D1 and R D2 Examples of the hydrocarbon group include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, nonyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and may be either saturated or unsaturated. Examples thereof include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclononyl group, cyclododecyl group, norbornyl group, adamantyl group. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, 1-naphthyl group, 2-naphthyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-propylphenyl group, 4-isopropylphenyl group, 4-butylphenyl group, 4-t-butylphenyl group, 4-hexylphenyl group, 4-cyclohexylphenyl group, anthryl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc. Examples of the group formed by combining these include alkyl-cycloalkyl group, cycloalkyl-alkyl group, aralkyl group (for example, phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1-phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, 6-phenyl-1-hexyl group, etc.). Examples of the alkoxy group include methoxy group, ethoxy group, etc. Examples of the acyl group include acetyl group, propanoyl group, benzoyl group, cyclohexanecarbonyl group, etc. Examples of the acyloxy group include the group in which an oxy group (-O-) is bonded to the above acyl group, etc. Examples of the alkoxycarbonyl group include the group in which a carbonyl group (-CO-) is bonded to the above alkoxy group, etc. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, etc. R D1 and R D2 are each independently preferably an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 2 to 4 carbon atoms, a nitro group or a halogen atom. m' and n' are each independently preferably any integer from 0 to 2, and more preferably 0. When m' is 2 or more, a plurality of RD1 may be the same or different, and when n' is 2 or more, a plurality of R D2 may be the same or different. More specifically, the following salts can be mentioned. TIFF2025100428000134.tif71166

[0195] Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. Examples of amines include aliphatic amines and aromatic amines. Examples of aliphatic amines include primary amines, secondary amines, and tertiary amines. Examples of the amine include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 1,2-di(4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridylsulfide, 4,4'-dipyridyldisulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine and the like. Aromatic amines such as diisopropylaniline are preferable, and 2,6-diisopropylaniline is more preferable. Examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, and choline.

[0196] <Other components> The resist composition of the present invention may contain, if necessary, components other than the above-described components (hereinafter sometimes referred to as "other components (F)"). There is no particular limitation on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used.

[0197] <Preparation of resist composition> The resist composition of the present invention can be prepared by mixing the resin (A), optionally the resin (A2) containing a structural unit having an acid-labile group, the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F), etc. The mixing order is arbitrary and is not particularly limited. The temperature at the time of mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is also not particularly limited, and stirring and mixing, etc. can be used. After mixing the respective components, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

[0198] <Method for producing resist pattern> The method for producing a resist pattern of the present invention is (1) A step of applying the resist composition of the present invention onto a substrate, (2) A step of drying the applied resist composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the composition layer after exposure, and (5) A step of developing the composition layer after heating. To apply the resist composition onto a substrate, it can be usually performed by an apparatus such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers and organic substrates having a resist film or the like formed on the surface. Before applying the resist composition, the substrate may be cleaned, or an antireflection film or the like may be formed on the substrate. By drying the applied composition, the solvent is removed to form a composition layer. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-bake), or by using a decompression device. The heating temperature is preferably 50 to 200 °C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during decompression drying is preferably about 1 to 1.0×10 5 Pa. The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, those that emit laser light in the ultraviolet region such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), those that convert laser light from a solid laser light source (YAG or semiconductor laser, etc.) to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams, extreme ultraviolet light (EUV), etc., various ones can be used. In this specification, irradiating these radiations may be collectively referred to as "exposure" in some cases. During exposure, usually, exposure is performed through a mask corresponding to the required pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask. The composition layer after exposure is heat-treated (so-called post-exposure bake) to promote the deprotection reaction at the acid-labile groups. The heating temperature is usually about 50 to 200°C, preferably about 70 to 150°C. Chemical treatment (silylation) may be performed to adjust the hydrophilicity or hydrophobicity of the resin on the surface side of the composition after heating. Also, before development, the steps of coating, drying, exposing, and heating the resist composition may be repeated on the composition layer after exposure. The composition layer after heating is usually developed using a developing solution with a developing apparatus. Examples of the developing method include dip method, paddle method, spray method, dynamic dispense method, etc. The developing temperature is preferably, for example, 5 to 60°C, and the developing time is preferably, for example, 5 to 300 seconds. By selecting the type of developing solution as follows, a positive resist pattern or a negative resist pattern can be manufactured. When manufacturing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developing solution. The alkaline developer may be various alkaline aqueous solutions used in this field. For example, aqueous solutions of tetramethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide (commonly called choline), etc. may be mentioned. The alkaline developer may contain a surfactant. It is preferable to wash the resist pattern with ultrapure water after development, and then remove the water remaining on the substrate and the pattern. When manufacturing a negative resist pattern from the resist composition of the present invention, a developing solution containing an organic solvent (hereinafter sometimes referred to as an "organic-based developing solution") is used as the developing solution. Examples of the organic solvent contained in the organic-based developing solution include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole, etc. In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and still more preferably substantially only the organic solvent. Among them, as the organic developer, a developer containing butyl acetate and / or 2-heptanone is preferable. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and still more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant. Further, the organic developer may contain a trace amount of water. During development, development may be stopped by substituting with a solvent of a type different from the organic developer. It is preferable to wash the resist pattern after development with a rinse solution. The rinse solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After washing, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

[0199] <Usage> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, particularly as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for semiconductor microfabrication.

Examples

[0200] The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing the content or the amount used are based on mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography. The analysis conditions for gel permeation chromatography are as follows. Column: TSKgel Multipore HXL-M x 3 + guard column (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 °C Injection volume: 100 μl Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC is Agilent 1100 type, MASS is Agilent LC / MSD type). In the following examples, the value of this molecular ion peak is indicated by "MASS".

[0201] Example 1: Synthesis of the compound represented by formula (I-5) 2.76 parts of the compound represented by formula (I-5-a) and 50 parts of chloroform were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 1.62 parts of carbonyldiimidazole was added, and the mixture was further stirred at 50 °C for 2 hours. To the resulting organic layer, 25 parts of 5% oxalic acid aqueous solution was added, and the mixture was stirred at 23 °C for 30 minutes, then separated to obtain the organic layer. To the obtained organic layer, 25 parts of ion-exchanged water was added and the mixture was stirred at 23 °C for 30 minutes, then separated to obtain the organic layer. This water washing operation was repeated 5 times. By concentrating the obtained organic layer, 3.59 parts of the compound represented by formula (I-5) was obtained. MASS: 371.0 [M+H] +

[0202] Example 2: Synthesis of the compound represented by formula (I-6) 3.72 parts of the compound represented by TIFF2025100428000136.tif3199 formula (I-6-a) and 50 parts of chloroform were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 1.62 parts of carbonyldiimidazole was added, and further stirred at 50 °C for 2 hours. To the resulting organic layer, 25 parts of 5% aqueous oxalic acid solution was added, stirred at 23 °C for 30 minutes, and then separated to extract the organic layer. To the resulting organic layer, 25 parts of ion-exchanged water was added, stirred at 23 °C for 30 minutes, and then separated to extract the organic layer. This water washing operation was repeated 5 times. By concentrating the resulting organic layer, 4.55 parts of the compound represented by formula (I-6) was obtained. MASS: 466.9 [M+H] +

[0203] Example 3: Synthesis of the compound represented by formula (I-9) 1.92 parts of the compound represented by TIFF2025100428000137.tif4693 formula (I-9-a) and 50 parts of chloroform were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 1.62 parts of carbonyldiimidazole was added, and further stirred at 50 °C for 2 hours. To the resulting organic layer, 25 parts of 5% aqueous oxalic acid solution was added, stirred at 23 °C for 30 minutes, and then separated to extract the organic layer. To the resulting organic layer, 25 parts of ion-exchanged water was added, stirred at 23 °C for 30 minutes, and then separated to extract the organic layer. This water washing operation was repeated 5 times. By concentrating the resulting organic layer, 2.66 parts of the compound represented by formula (I-9) was obtained. MASS: 287.0 [M+H] +

[0204] Example 4: Synthesis of the compound represented by formula (I-13) 1.20 parts of the compound represented by TIFF2025100428000138.tif4294 formula (I-13-a) and 50 parts of chloroform were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 1.62 parts of carbonyldiimidazole were added, and the mixture was further stirred at 50 °C for 2 hours. To the resulting organic layer, 25 parts of a 5% aqueous oxalic acid solution were added, and the mixture was stirred at 23 °C for 30 minutes. After liquid separation, the organic layer was taken out. To the resulting organic layer, 25 parts of ion-exchanged water were added, and the mixture was stirred at 23 °C for 30 minutes. After liquid separation, the organic layer was taken out. This water washing operation was repeated 5 times. By concentrating the resulting organic layer, 2.07 parts of the compound represented by formula (I-13) were obtained. MASS: 215.1 [M+H] +

[0205] Example 5: Synthesis of the compound represented by formula (I-14) 1.20 parts of the compound represented by TIFF2025100428000139.tif3099 formula (I-14-a) and 50 parts of chloroform were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 1.62 parts of carbonyldiimidazole were added, and the mixture was further stirred at 50 °C for 2 hours. To the resulting organic layer, 25 parts of a 5% aqueous oxalic acid solution were added, and the mixture was stirred at 23 °C for 30 minutes. After liquid separation, the organic layer was taken out. To the resulting organic layer, 25 parts of ion-exchanged water were added, and the mixture was stirred at 23 °C for 30 minutes. After liquid separation, the organic layer was taken out. This water washing operation was repeated 5 times. By concentrating the resulting organic layer, 2.03 parts of the compound represented by formula (I-14) were obtained. MASS: 215.1 [M+H] +

[0206] Synthesis of resin The compounds (monomers) used in the synthesis of resin (A) are shown below. Hereinafter, these compounds will be referred to as "monomer (a1-1-3)" etc. according to their formula numbers. TIFF2025100428000140.tif66163

[0207] Example 6 [Synthesis of Resin A1] As monomers, 4-acetoxystyrene, monomer (a1-4-2) and monomer (I-1) were used and mixed so that their molar ratio [4-acetoxystyrene: monomer (a1-4-2): monomer (I-1)] was 40:56:4. Further, 1.5 mass times of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, stirred for 3 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and the weight average molecular weight was about 5.0×10 3 Resin A1 (copolymer) having this was obtained at a yield of 78%. This resin A1 has the following structural units. TIFF2025100428000141.tif30126

[0208] Example 7 [Synthesis of Resin A2] As monomers, 4-acetoxystyrene, monomer (a1-6-8) and monomer (I-1) were used and mixed so that their molar ratio [4-acetoxystyrene: monomer (a1-6-8): monomer (I-1)] was 40:56:4. Further, 1.5 mass times of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, stirred for 3 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and the weight average molecular weight was about 5.1×10 3 Resin A2 (copolymer) having this was obtained at a yield of 75%. This resin A2 has the following structural units. TIFF2025100428000142.tif27126

[0209] Example 8 [Synthesis of Resin A3] As monomers, monomer (a2-B-1), monomer (a1-6-8), and monomer (I-1) were used and mixed so that their molar ratio [monomer (a2-B-1): monomer (a1-6-8): monomer (I-1)] was 40:56:4. Further, 1.5 times the mass of methyl isobutyl ketone with respect to the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% with respect to the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A3 (copolymer) having a weight average molecular weight of about 4.8×10 3 in a yield of 83%. This resin A3 has the following structural units. TIFF2025100428000143.tif28129

[0210] Example 9 [Synthesis of Resin A4] As monomers, 4-acetoxystyrene, monomer (a1-6-8), monomer (I-1), and monomer (a7-1) were used and mixed so that their molar ratio [4-acetoxystyrene: monomer (a1-6-8): monomer (I-1) and monomer (a7-1)] was 40:46:4:10. Further, 1.5 times the mass of propylene glycol monomethyl ether with respect to the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% with respect to the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 3 hours, the solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain a weight average molecular weight of about 4.9×10 3Resin A4 (copolymer) was obtained in a yield of 70%. This resin A4 has the following structural units. TIFF2025100428000144.tif48161

[0211] Example 10 [Synthesis of Resin A5] As monomers, 4-acetoxystyrene, monomer (a1-6-8), monomer (I-5), and monomer (a7-1) were used and mixed so that their molar ratio [4-acetoxystyrene: monomer (a1-6-8): monomer (I-5) and monomer (a7-1)] was 40:46:4:10. Further, propylene glycol monomethyl ether 1.5 times the total mass of all the monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all the monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 3 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby a resin A5 (copolymer) having a weight average molecular weight of about 4.7×10 3 was obtained in a yield of 73%. This resin A5 has the following structural units. TIFF2025100428000145.tif47161

[0212] Example 11 [Synthesis of Resin A6] As monomers, 4-acetoxystyrene, monomer (a1-6-8), monomer (I-6), and monomer (a7-1) were used, and they were mixed so that the molar ratio [4-acetoxystyrene: monomer (a1-6-8): monomer (I-6) and monomer (a7-1)] was 40:46:4:10. Further, 1.5 times the mass of propylene glycol monomethyl ether based on the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Then, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 3 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. The resin A6 (copolymer) having a weight average molecular weight of about 4.5×10 3 was obtained in a yield of 68%. This resin A6 has the following structural units. TIFF2025100428000146.tif47165

[0213] Example 12 [Synthesis of Resin A7] As monomers, 3-acetoxystyrene, monomer (a1-6-8), and monomer (I-1) were used, and they were mixed so that the molar ratio [3-acetoxystyrene: monomer (a1-6-8): monomer (I-1)] was 40:56:4. Further, 1.5 times the mass of methyl isobutyl ketone based on the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Then, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 3 hours, liquid separation was carried out. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. The resin A7 (copolymer) having a weight average molecular weight of about 5.2×10 3 was obtained in a yield of 73%. This resin A7 has the following structural units. TIFF2025100428000147.tif27126

[0214] Example 13 [Synthesis of Resin A8] As monomers, monomer (a2-2-4), monomer (a1-6-8), monomer (I-6), and monomer (a7-1) were used, and their molar ratio [monomer (a2-2-4): monomer (a1-6-8): monomer (I-6) and monomer (a7-1)] was mixed so as to be in a ratio of 40:46:4:10. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby resin A8 (copolymer) having a weight average molecular weight of about 4.8×10 3 was obtained at a yield of 77%. This resin A8 has the following structural units. TIFF2025100428000148.tif47165

[0215] Example 14 [Synthesis of Resin A9] As monomers, monomer (a2-2-4), monomer (a1-6-8), monomer (I-5), and monomer (a7-1) were used, and their molar ratio [monomer (a2-2-4): monomer (a1-6-8): monomer (I-5) and monomer (a7-1)] was mixed so as to be in a ratio of 40:46:4:10. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby resin A9 having a weight average molecular weight of about 5.0×10 3Resin A9 (copolymer) was obtained in a yield of 79%. This Resin A9 has the following structural units. TIFF2025100428000149.tif47161

[0216] Example 15 [Synthesis of Resin A10] As monomers, monomer (a2-2-4), monomer (a1-6-8), monomer (I-9), and monomer (a7-1) were used and mixed so that their molar ratio [monomer (a2-2-4): monomer (a1-6-8): monomer (I-9) and monomer (a7-1)] was 40:46:4:10. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain Resin A10 (copolymer) having a weight average molecular weight of about 5.1×10 3 in a yield of 82%. This Resin A10 has the following structural units. TIFF2025100428000150.tif47164

[0217] Example 16 [Synthesis of Resin A11] As monomers, monomer (a2-2-4), monomer (a1-6-8), monomer (I-13), and monomer (a7-1) were used and mixed so that their molar ratio [monomer (a2-2-4): monomer (a1-6-8): monomer (I-13) and monomer (a7-1)] was 40:46:4:10. Further, propylene glycol monomethyl ether at 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator at 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A11 (copolymer) having a weight average molecular weight of about 5.3×10 3 in a yield of 85%. This resin A11 has the following structural units. TIFF2025100428000151.tif47164

[0218] Example 17 [Synthesis of Resin A12] As monomers, monomer (a2-2-4), monomer (a1-6-8), monomer (I-14), and monomer (a7-1) were used and mixed so that their molar ratio [monomer (a2-2-4): monomer (a1-6-8): monomer (I-14) and monomer (a7-1)] was 40:46:4:10. Further, propylene glycol monomethyl ether at 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator at 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A12 (copolymer) having a weight average molecular weight of about 5.5×10 3 in a yield of 77%. This resin A12 has the following structural units. TIFF2025100428000152.tif47169

[0219] Synthesis Example 1 [Synthesis of Resin AX1] As monomers, 4-acetoxystyrene, monomer (a1-0-1), and monomer (I-1) were used, and they were mixed so that the molar ratio [4-acetoxystyrene: monomer (a1-0-1): monomer (I-1)] was 40:56:4. Further, 1.5 mass times of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Then, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, stirred for 3 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby resin AX1 (copolymer) having a weight average molecular weight of about 5.3×10 3 was obtained in a yield of 84%. This resin AX1 has the following structural units. TIFF2025100428000153.tif25129

[0220] Synthesis Example 2 [Synthesis of Resin AX2] As monomers, 3-acetoxystyrene, monomer (a1-2-6), and monomer (I-1) were used, and they were mixed so that the molar ratio [3-acetoxystyrene: monomer (a1-2-6): monomer (I-1)] was 40:56:4. Further, 1.5 mass times of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 15 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 73 °C for about 5 hours. Then, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, stirred for 3 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby resin AX2 having a weight average molecular weight of about 5.1×10 3The resin AX2 (copolymer) was obtained with a yield of 87%. This resin AX2 has the following structural units. TIFF2025100428000154.tif23129

[0221] <Preparation of Resist Composition> As shown in Table 1, the following components were mixed, and the resulting mixture was filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a resist composition.

Table 1

[0222] <Resin> A1~A12, AX1, AX2: Resin A1~Resin A12, Resin AX1, Resin AX2 <Acid Generator> B1-43: Salt represented by formula (B1-43) (synthesized according to the examples of JP-A-2016-47815) TIFF2025100428000156.tif44115<Quencher (C)> C1: Synthesized by the method described in JP-A-2011-39502 TIFF2025100428000157.tif3660<Solvent> 400 parts of propylene glycol monomethyl ether acetate 100 parts of propylene glycol monomethyl ether 5 parts of γ-butyrolactone

[0223] (Electron Beam Exposure Evaluation of Resist Composition) A 6-inch silicon wafer was treated with hexamethyldisilazane on a direct hot plate at 90 °C for 60 seconds. A resist composition was spin-coated onto this silicon wafer so that the film thickness of the composition layer was 0.04 μm. Then, it was prebaked on a direct hot plate at the temperature shown in the "PB" column of Table 1 for 60 seconds to form a composition layer. Using an electron beam lithography machine ["ELS-F125 125 keV" manufactured by Elionix, Inc.], a contact hole pattern (hole pitch 40 nm / hole diameter 17 nm) was directly drawn on the composition layer formed on the wafer by gradually changing the exposure dose. After exposure, post-exposure baking was performed on a hot plate at the temperature shown in the "PEB" column of Table 1 for 60 seconds, and further paddle development was performed with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide for 60 seconds to obtain a resist pattern.

[0224] In the resist pattern obtained after development, the exposure dose at which the formed hole diameter became 17 nm was defined as the effective sensitivity.

[0225] <CD Uniformity (CDU) Evaluation> At the effective sensitivity, the hole diameter of the pattern formed with a hole diameter of 17 nm was measured 24 times for each hole, and the average value was taken as the average hole diameter of one hole. Using as the population the measurement of the average hole diameter of the patterns formed with a hole diameter of 17 nm at 400 locations within the same wafer, the standard deviation was determined. The results are shown in Table 2. The numerical values in the table indicate the standard deviation (nm).

Table 2

Industrial Applicability

[0226] The resist composition of the present invention has good CD uniformity (CDU) and is useful for fine processing of semiconductors.

Claims

1. A resist composition containing a resin including a structural unit represented by formula (I) and at least one selected from the group consisting of a structural unit represented by formula (a1-4) and a structural unit represented by formula (a1-6). [In formula (I), Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R 1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X １１ represents a single bond or *-Ar-O-CO-. * represents the bonding site with the carbon atom to which R １ is bonded. [In formula (a1-4), R ｃ１ , R ｃ２ and R ｃ３ each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 48 carbon atoms, and the hydrocarbon group may have a substituent, and -CH ２ - in the hydrocarbon group may be replaced by -O-, -CO-, -S-, or -SO ２ -.] na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. R ａ１ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ１７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ１１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ１８ -. R ａ１８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ１ represents a single bond or a carbonyl group. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and -CH 2 - contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. mc represents any integer from 0 to 2.]] na11 represents any integer from 0 to 4, and when na11 is 2 or more, a plurality of Rs ａ１７ may be the same as or different from each other. [In formula (I), Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R a61 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a6２ 、R a63 and R a6４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a6２ and R a63 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded. X a61 represents a single bond, -CO-O-*, or -CO-NR a65 -*, where * represents the bonding site with -Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 - or *-CO-O-L a62 -, where * represents the bonding site with Ar, and L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. [In formula (a1-4), na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]] [In formula (I), A ａ１１ and X a61 The resist composition according to claim 1, wherein is a single bond. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. [In formula (a1-4), na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. R ａ２ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ２８ -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ２ represents a single bond or a carbonyl group. mc represents any integer from 0 to 2.]] na21 represents any integer from 0 to 4, and when na21 is 2 or more, a plurality of Rs ａ２７ may be the same as or different from each other. [In formula (a1-4), na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]] [In formula (a1-4), R ａ２ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ２８ -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ａ２１ and R ａ２２ each independently represents an alkyl fluoride group having 1 to 4 carbon atoms. L ａ２４ represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]] nD22 represents any integer from 0 to 4. When nD22 is 2 or more, a plurality of Rs ａ２７ may be the same as or different from each other.] [In formula (a1-4), na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]] R ａ７ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X ａ７１ represents a single bond, *-O-, *-CO-O-, *-O-CO-O-**, *-CO-NR ａ７１ -**, *-NR ａ７１ -CO-O-**, *-O-CO-NR ａ７１ -** or *-Ax-Ph-Ay-**. R ａ７１ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. [In formula (a1-6), Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.]] * and ** represent binding sites, and * represents the binding site with the carbon atom to which R ａ７ is attached. L ａ７１ and L ａ７２ each independently represents a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. X ａ７２ represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, and *** represents L ａ７１ represents the binding site with L. [In formula (a1-6), RA － represents a sulfonic acid anion or a carboxylic acid anion. ZA ＋ represents an organic cation. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.]]

2. The resist composition according to claim 1, containing only one of the structural unit (a1-4) and the structural unit (a1-6).

3. L b1 represents a (nb1 + 1)-valent hydrocarbon group which may have a single bond or substituents, and -CH 2 - contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. L b2 represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH 2 - in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO 2 - or -CO-.

4. Z1 ＋ represents an organic cation. The resist composition according to claim 1, wherein the resin further contains a structural unit represented by formula (a2-A). [In formula (a2-A), nA2 represents any integer from 1 to 5. When nA2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]] [In formula (a2-A), nA2 represents any integer from 1 to 5. When nA2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]] [In formula (a2-A), nA2 represents any integer from 1 to 5. When nA2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. mc represents any integer from 0 to 2.]]

5. The resist composition according to claim 1, wherein the resin further contains a structural unit represented by formula (a2-D). [In formula (a2-D), nD2 represents any integer from 1 to 4. When nD2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]] [In formula (a2-D), nD2 represents any integer from 1 to 4. When nD2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]] [In formula (a2-D), nD2 represents any integer from 1 to 4. When nD2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]]

6. The resist composition according to claim 1, wherein the resin further contains a structural unit represented by formula (a7-A). [In formula (a7-A), Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. na7 represents an integer from 0 to 2. When na7 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]] [In formula (a7-A), Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. na7 represents an integer from 0 to 2. When na7 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]] [In formula (a7-A), Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. na7 represents an integer from 0 to 2. When na7 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]] [In formula (a7-A), Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. na7 represents an integer from 0 to 2. When na7 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]]

7. Further containing an acid generator, The resist composition according to claim 1, wherein the acid generator is a salt represented by formula (B1). [In formula (B1), nb1 represents any integer from 1 to 6. When nb1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]] [In formula (B1), nb1 represents any integer from 1 to 6. When nb1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other.]]

8. The resist composition according to claim 7, further comprising a salt that generates an acid having a lower acidity than the acid generated from the acid generator.

9. (1) A step of applying the resist composition according to any one of claims 1 to 8 onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) A step of exposing the composition layer; (4) A step of heating the composition layer after exposure; and (5) A step of developing the composition layer after heating, A method for manufacturing a resist pattern including the above steps.

10. A resin including a structural unit represented by formula (I) and at least one selected from the group consisting of a structural unit represented by formula (a1-4) and a structural unit represented by formula (a1-6). [In formula (I), Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R 1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X １１ represents a single bond or *-Ar-O-CO-. * represents the bonding site with the carbon atom to which R １ is bonded. [In formula (a1-4), R ｃ１ , R ｃ２ and R ｃ３ each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 48 carbon atoms, the hydrocarbon group may have a substituent, and -CH ２ - in the hydrocarbon group may be replaced by -O-, -CO-, -S-, or -SO ２ -]. na1 represents an integer of any one of 1 to 5. When na1 is 2 or more, the groups in a plurality of parentheses may be the same as or different from each other. R ａ１ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ１７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ１１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ１８ -. R ａ１８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ１ represents a single bond or a carbonyl group. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and -CH 2 - contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. mc represents an integer of any one of 0 to 2. ] na11 represents any integer from 0 to 4, and when na11 is 2 or more, a plurality of Rs ａ１７ may be the same as or different from each other. [In formula (a1-6), Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. ] R a61 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a6２ , R a63 and R a6４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a6２ and R a63 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. X a61 represents a single bond, -CO-O-*, or -CO-NR a65 -*, where * represents the bonding site with -Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 - or *-CO-O-L a62 -, where * represents the bonding site with Ar, and L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms.

11. The resin according to claim 10, including only one of the structural units represented by formula (a1-4) and formula (a1-6).

12.

13. A ａ１１ and X a61 The resin according to claim 10, wherein the bond is a single bond. The resin according to claim 10, further including at least one selected from the group consisting of a structural unit represented by formula (a2-A), a structural unit represented by formula (a2-D), and a structural unit represented by formula (a7-A). [In formula (a2-A), nA2 represents an integer of any one of 1 to 5. When nA2 is 2 or more, the groups in a plurality of parentheses may be the same as or different from each other. R ａ２ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ２８ -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ２ represents a single bond or a carbonyl group. mc represents an integer of any one of 0 to 2. ] na21 represents any integer from 0 to 4, and when na21 is 2 or more, a plurality of Rs ａ２７ may be the same as or different from each other. [In formula (a2-D), nD2 represents an integer of any one of 1 to 4. R ａ２ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ２８ -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ａ２１ and R ａ２２ each independently represents an alkyl fluoride group having 1 to 4 carbon atoms. L ａ２４ represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. When nD2 is 2 or more, the groups in a plurality of parentheses may be the same as or different from each other. [In formula (a7-A), nD22 represents any integer from 0 to 4. When nD22 is 2 or more, a plurality of Rs ａ２７ may be the same as or different from each other.] Ph represents a phenylene group which may have a substituent. R ａ７ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X ａ７１ represents a single bond, *-O-, *-CO-O-, *-O-CO-O-**, *-CO-NR ａ７１ -**, *-NR ａ７１ -CO-O-**, *-O-CO-NR ａ７１ -** or *-Ax-Ph-Ay-**. R ａ７１ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. na7 represents an integer of 0 to 2. When na7 is 2 or more, the groups in a plurality of parentheses may be the same as or different from each other. * and ** represent the binding sites, and * represents the binding site with the carbon atom to which R ａ７ is attached. L ａ７１ and L ａ７２ each independently represents a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 - X ａ７２ represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, where *** represents L ａ７１ and represents the binding site with L.

14. RA － represents a sulfonate anion or a carboxylate anion. ZA ＋ represents an organic cation. A resin including a structural unit represented by formula (IA). [In formula (IA), ​ R 1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R ｃ１ 、 R ｃ２ and R ｃ３ each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 48 carbon atoms, the hydrocarbon group may have a substituent, and the -CH ２ - in the hydrocarbon group may be replaced by -O-, -CO-, -S-, or -SO ２ -. ] **Claim 15** A compound represented by formula (IA-s). [In formula (IA-s), R 1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R ｃ１ , R ｃ２ and R ｃ３ each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 48 carbon atoms, and the hydrocarbon group may have a substituent, and -CH ２ - in the hydrocarbon group may be replaced by -O-, -CO-, -S-, or -SO ２ -. ]

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