Resist composition and method for producing resist pattern

Abstract

To provide a resist composition from which a resist pattern having good line edge roughness can be produced.SOLUTION: The resist composition contains a compound represented by formula (I) and an acid generator. [In the formula (I), R1 represents a hydrogen atom or a substituted / unsubstituted hydrocarbon group, and -CH2- contained in the hydrocarbon group may be substituted with -O-, -S- or the like; R2 represents a hydrogen atom or an alkyl group; ring W represents a substituted / unsubstituted alicyclic hydrocarbon ring, and -CH2- contained in the alicyclic hydrocarbon ring may be substituted with -O-, -S-, -CO- or -SO2-; X0 represents a halogen atom or a hydrocarbon group having a halogen atom, and -CH2- contained in the hydrocarbon group may be substituted with -O-, -S- or the like; nc1 represents an integer of 1-6; and when nc1 is 2 or more, a plurality of groups in parentheses may be the same as or different from each other.]SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002] Patent Document 1 describes a resist composition containing a compound represented by the following structural formula and an acid generator. TIFF2025097300000001.tif1324

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a resist composition that forms a resist pattern having better line edge roughness (LER) than a resist pattern formed from the above resist composition.

Means for Solving the Problems

[0005] The present invention includes the following inventions. [1] A resist composition containing a compound represented by formula (I) and an acid generator. TIFF2025097300000002.tif2582[In formula (I), R 1 represents a hydrogen atom or 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-, -NR 2 -, or -SO2-. R 2 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. Ring W represents an alicyclic hydrocarbon ring having 3 to 36 carbon atoms which may have a substituent, and -CH2- contained in the alicyclic hydrocarbon ring may be replaced by -O-, -S-, -CO- or -SO2-. X 0 represents a halogen atom or a hydrocarbon group having 1 to 72 carbon atoms having a halogen atom, -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the hydrocarbon group may have a substituent other than a halogen atom. nc1 represents any integer from 1 to 6. When nc1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. [2]X 0 is an iodine atom, an alkyl fluoride group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a group formed by combining two or more selected from the group consisting of a chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and an aromatic hydrocarbon group having 6 to 36 carbon atoms (the alicyclic hydrocarbon group and the chain hydrocarbon group may have a fluorine atom, an alkyl fluoride group having 1 to 4 carbon atoms, or a hydroxy group, the aromatic hydrocarbon group may have a fluorine atom, an iodine atom, an alkyl fluoride group having 1 to 4 carbon atoms, or a hydroxy group, and -CH2- contained in the alicyclic hydrocarbon group and the chain hydrocarbon group may be replaced by -O- or -CO-). The resist composition according to [1]. [3] The resist composition according to [1] or [2], wherein the acid generator contains a salt represented by formula (B1). TIFF2025097300000003.tif1391[In formula (B1), L b1 represents a single bond or a (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 single bond or a divalent 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-. Yb1 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 any integer from 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. A resist composition according to any one of [1] to [3], further comprising a [4] resin, the resin containing a structural unit represented by formula (a2-A). TIFF2025097300000004.tif30128[In 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. When nA2 is 2 or more, the groups in a 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, a plurality of R a27 may be the same as or different from each other. mc represents an integer of any one of 0 to 2. Further includes a structural unit having an acid-labile group, The resist composition according to any one of [1] to [4], wherein the structural unit having an acid-labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). TIFF2025097300000005.tif44144 [In formula (a1-0), formula (a1-1) and 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 any one of 1 to 7, and * represents the bonding site with -CO-. R a01 、R a4 and R a5 each 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 an integer of any one of 0 to 14. n1 represents an integer of any one of 0 to 10. n1’ represents any integer from 0 to 3. TIFF2025097300000006.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 R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with -C-O- to which they are bonded, and -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. TIFF2025097300000007.tif4558[In 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 any one of 1 to 4, and * represents the bonding site with L 51 . L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-. s1 represents an integer of any one of 1 to 3. s1’ represents an integer of any one of 0 to 3.] TIFF2025097300000008.tif3681[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 -*, * 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 -, * represents the bonding site with 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. [6](1) A step of applying the resist composition according to any one of [1] to [5] on a substrate, (2) A step of drying the applied 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, A method for manufacturing a resist pattern including these steps.

Effect of the Invention

[0006] By using the resist composition of the present invention, a resist pattern can be manufactured with good line edge roughness (LER).

Mode for Carrying Out the Invention

[0007] In this specification, the “(meth)acrylic monomer” means “at least one of an acrylic monomer and a methacrylic monomer”. Similarly, 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. For -CH2- contained in a hydrocarbon group or the like, it is -O-, -S-, -CO-, -SO-, -NR XWhen replaced by -(X is any sign) or -SO2-, the same examples apply to each group, and the number of carbon atoms before replacement is defined as the number of carbon atoms of hydrocarbon groups and the like. "Combined group" means a group formed by combining two or more of the exemplified groups, and the valences of these groups may be appropriately changed depending on the bonding form. "Derived from" or "induced" means that the polymerizable C=C bond contained in the molecule becomes a single bond (-C-C-) by polymerization or any hydrogen atom becomes a bonding site. When stereoisomers exist, all stereoisomers are included. "Acid-labile group" means a group that, when contacted with an acid (e.g., trifluoromethanesulfonic acid, etc.), the leaving group leaves to form a hydrophilic group (e.g., hydroxy group or carboxy group). "Base-labile group" means a group that, when contacted with a base (e.g., trimethylamine, tetramethylammonium hydroxide, etc.), the leaving group leaves to form a hydrophilic group (carboxy group or hydroxy group). Each group may have any position and number of hydrogen atoms contained in the group replaced by a bond depending on the number of substituents and the like. The number of carbon atoms in the substituent is not included in the number of carbon atoms of the group being substituted. In this specification, "the 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.

[0008] 〔Resist Composition〕 The resist composition of the present invention contains a compound represented by formula (I) (hereinafter sometimes referred to as "compound (I)") and an acid generator (hereinafter sometimes referred to as "acid generator (B)"). The resist composition of the present invention may further contain a resin. Examples of the resin include a resin containing a structural unit having an acid-labile group (hereinafter sometimes referred to as "resin (A)"). Here, the "acid-labile group" means a group having a leaving group that, upon contact with an acid, the leaving group leaves to convert to a structural unit having a hydrophilic group (e.g., hydroxy group or carboxy group). Further, a resin other than resin (A) may be contained. The resist composition of the present invention preferably further contains a quencher such as a salt that generates an acid having a lower acidity than the acid generated from the acid generator (hereinafter sometimes referred to as "quencher (C)"), and more preferably contains a solvent (hereinafter sometimes referred to as "solvent (E)").

[0009] <Compound (I)> The resist composition of the present invention contains Compound (I). TIFF2025097300000009.tif2582[In formula (I), all symbols have the same meanings as described above.]

[0010] In formula (I), R 1 Examples of the hydrocarbon group of include chain hydrocarbon groups such as alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, and n-dodecyl group. The number of carbon atoms of the chain hydrocarbon group may be 1 to 24, preferably an alkyl group having 1 to 12 carbon atoms, and more preferably an alkyl group having 1 to 6 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, methylcyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cycloheptyl group, cyclodecyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1-(adamantan-1-yl)alkane-1-yl group, norbornyl group, methylnorbornyl group and isobornyl group and the like. The number of carbon atoms of the alicyclic hydrocarbon group may be 3 to 24, preferably an alicyclic hydrocarbon group having 6 to 12 carbon atoms, more preferably an alicyclic hydrocarbon group having 6 to 10 carbon atoms. Examples of the aromatic hydrocarbon group include phenyl group, tosyl group, naphthyl group, biphenyl group, xylyl group, anthracenyl group and the like. The number of carbon atoms of the aromatic hydrocarbon group may be 6 to 24, preferably an aromatic hydrocarbon group having 6 to 18 carbon atoms, more preferably phenyl group or naphthyl group. The group formed by combination may contain one or more of a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group respectively. For example, an aralkyl group may be mentioned, and benzyl group, phenethyl group and the like may be mentioned. R 2 Examples of the alkyl group of R 1 are the same groups as the alkyl group of R within the range allowed by the upper limit of the number of carbon atoms. When -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -CO-, -NR 2 - or -SO2-, the total number of carbon atoms before replacement is taken as the total number of carbon atoms of the hydrocarbon group. Also, the number may be one or two or more. When -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -CO-, -NR 2-or- As the group replacing -SO2-, a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), an amino group (a group in which -CH2- contained in a methyl group is replaced by -NR 2 -), 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 alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), 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 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 alkylamino group (a group in which -CH2- contained in an alkyl group is replaced by -NR 2-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-thio group (a group in which any -CH2- in the alkanediyl group is replaced by -S-), an alkanediyl-sulfonyl group (a group in which any -CH2- in the alkanediyl group is replaced by -SO2-), an alkanediyl-amino group (a group in which any -CH2- in the alkanediyl group is replaced by -NH-), an alkanediyl-peptide group (a group in which any -CH2-CH2- in the alkanediyl group is replaced by -CO-NR 2 -replaced group), groups formed by combining two or more of these groups, and the like.

[0011] Examples of the alkoxy group include alkoxy groups having 1 to 12 carbon atoms, such as methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, undecyloxy group and the like. The number of carbon atoms of the alkoxy group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylthio group include alkylthio groups having 1 to 12 carbon atoms, such as methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, hexylthio group, octylthio group, 2-ethylhexylthio group, nonylthio group, decylthio group, undecylthio group and the like. The number of carbon atoms of the alkylthio group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 12 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 12 carbon atoms, such as acetyl group, propionyl group and butyryl group and the like. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 12 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 22 carbon atoms, such as butoxycarbonyloxy group and the like. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3. The number of carbon atoms of the alkoxycarbonyloxy group may be 3 to 12 or 3 to 10, preferably 3 to 6, and more preferably 3 to 4. Examples of the alkylthio group include alkylthio groups having 1 to 12 carbon atoms, such as methylthio group, ethylthio group, propylthio group and the like. The number of carbon atoms of the alkylthio group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 12 carbon atoms, such as methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, butylsulfonyl group, pentylsulfonyl group, hexylsulfonyl group, octylsulfonyl group, 2-ethylhexylsulfonyl group, nonylsulfonyl group, decylsulfonyl group, undecylsulfonyl group and the like. The number of carbon atoms of the alkylsulfonyl group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylamino group include alkylamino groups having 1 to 12 carbon atoms, such as methylamino group, ethylamino group, propylamino group, butylamino group, pentylamino group, hexylamino group, octylamino group, 2-ethylhexylamino group, nonylamino group, decylamino group, undecylamino group and the like. The number of carbon atoms of the alkylamino group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanedioxy group include alkanedioxy groups having 1 to 12 carbon atoms, such as methyleneoxy group, ethyleneoxy group, propanedioloxy group, butanedioloxy group, pentanedioloxy group and the like. The number of carbon atoms of the alkanedioxy group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3.

[0012] Examples of the alkanediyl-oxycarbonyl group include alkanediyl-oxycarbonyl groups having 2 to 12 carbon atoms, such as a methylene-oxycarbonyl group, an ethylene-oxycarbonyl group, a propanediyl-oxycarbonyl group, and a butanediyl-oxycarbonyl group. Examples of the alkanediyl-carbonyl group include alkanediyl-carbonyl groups having 2 to 18 carbon atoms, such as a methylene-carbonyl group, an ethylene-carbonyl group, a propanediyl-carbonyl group, a butanediyl-carbonyl group, and a pentanediyl-carbonyl group. Examples of the alkanediyl-carbonyl-oxy group include alkanediyl-carbonyl-oxy groups having 2 to 12 carbon atoms, such as a methylene-carbonyl-oxy group, an ethylene-carbonyl-oxy group, a propanediyl-carbonyl-oxy group, and a butanediyl-carbonyl-oxy group. The number of carbon atoms of the alkanediyl-oxycarbonyl group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3. The number of carbon atoms of the alkanediyl-carbonyl group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3. The number of carbon atoms of the alkanediyl-carbonyl-oxy group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3. Examples of the alkanediyl-thio group include alkanediyl-thio groups having 1 to 12 carbon atoms, such as a methylene-thio group, an ethylene-thio group, and a propylene-thio group. The number of carbon atoms of the alkanediyl-thio group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylsulfonyl group include alkanediylsulfonyl groups having 1 to 12 carbon atoms, such as methylenesulfonyl group, ethylenesulfonyl group, propylenesulfonyl group and the like. The number of carbon atoms of the alkanediylsulfonyl group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 12 carbon atoms, such as methyleneamino group, ethyleneamino group, propyleneamino group and the like. The number of carbon atoms of the alkanediylamino group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylpeptide group include methylenepeptide group, ethylenepetide group, propylpeptide group and the like. The number of carbon atoms of the alkanediylpeptide group is preferably 1 to 6, more preferably 1 to 4, and still more preferably 1 to 3. In addition, -CH2- contained in a group formed by combining an alicyclic hydrocarbon group or an alicyclic saturated hydrocarbon group with an aromatic hydrocarbon group is replaced by -O-, -CO-, -S-, -SO-, -SO2- or -NR 2 Examples of the group thus replaced include the following groups and the like. -O- or -CO- in the groups represented below may each be replaced by -S-, -SO-, -SO2- or -NR 2 -. The bonding site can be at any position. TIFF2025097300000010.tif74167

[0013] R 1 Examples of the substituent that the hydrocarbon group of R may optionally 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. Preferably, it is a fluorine atom. R 1 When R is 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. Further, R 1The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced by -O-, -CO-, etc., so that R 1 The hydrocarbon group of 1 can 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, a sulfonyl group, etc. R 1 Examples of R include a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and a group formed by combining these (however, -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). A hydrogen atom and an alkyl group having 1 to 12 carbon atoms are more preferable.

[0014] Examples of the alicyclic hydrocarbon ring having 3 to 36 carbon atoms in ring W are the same as those exemplified for the alicyclic hydrocarbon group of R 1 and rings represented by formula (a-1) to formula (a-11) are preferable, an alicyclic hydrocarbon ring having 3 to 18 carbon atoms is more preferable, and a ring represented by formula (a-1), a ring represented by formula (a-2) or a ring represented by formula (a-3) are even more preferable. The bonding site can be at any position. TIFF2025097300000011.tif27165[In formula (a-1) to formula (a-11), -CH2- contained in the ring may be replaced by -O-, -S-, -CO- or -SO2-, and the hydrogen atom contained in the ring may have a substituent.] Examples of the substituent that ring W may have include an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon ring having 3 to 36 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, a halogen atom, a cyano group, and a nitro group. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, dodecyl group and the like. Examples of the alkoxy group having 1 to 12 carbon atoms include methoxy group, ethoxy group, n-propoxy group, n-butoxy group, n-pentyloxy group, n-hexyloxy group, n-octyloxy group, 2-ethylhexyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group and n-dodecyloxy group. Examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include the groups shown below. The bonding site can be at any position. Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include phenyl group and naphthyl group. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom and iodine atom. For the group in which -CH2- contained in the alicyclic hydrocarbon ring of ring W is replaced by -O-, -S-, -CO- or -SO2-, within the range allowed by the upper limit of the number of carbon atoms, the groups exemplified in this specification, for example, R 1 include those similar to those exemplified by.

[0015] X 0 Examples of the halogen atom of X include fluorine atom, chlorine atom, bromine atom, iodine atom and the like. X 0 Examples of the hydrocarbon group of X include a (nc1)-valent hydrocarbon group, which is a group obtained by removing (nc1-1) hydrogen atoms from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining two or more of these groups. Examples of the chain hydrocarbon group include a group obtained by removing (nc1-1) 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, 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, decanyl group, undecanyl group, dodecanyl group, tridecanyl group, tetradecanyl group, pentadecanyl group, heptadecanyl group, etc. 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 1 to 48, more preferably 1 to 36, still more preferably 1 to 20, even more preferably 1 to 18, still even more preferably 1 to 12, and most preferably 1 to 10. Examples of the alicyclic hydrocarbon group include a group obtained by removing (nc1-1) hydrogen atoms from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include cyclobutyl group, cyclopentane group, cyclohexane group, cyclopentyl group, cyclooctyl group, etc. 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 norbornyl group, adamantyl group, etc. Examples of the cycloalkyl group in which two or more rings are condensed include bicyclo[4,4,0]decane group, steroid group (steroid skeleton), etc. Examples of the ring in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one or more cycloalkyl groups selected from the group consisting of cyclopentyl group, cyclohexyl group, norbornyl group, and adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. In addition, a double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include those represented by the following formula. TIFF2025097300000013.tif27165When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is, for example, 3 to 24, preferably 3 to 12, and more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is, for example, 7 to 48, preferably 7 to 36, more preferably 7 to 24, still more preferably 7 to 18, and even more preferably 7 to 12. Examples of the aromatic hydrocarbon group include an aryl group from which (nc1-1) hydrogen atoms have been removed. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorene group, and the like. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, and more preferably 5 to 10. X 0 When the -CH2- contained in the hydrocarbon group of X is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is defined as the number of carbon atoms in the hydrocarbon group. X 0Among 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 the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in the methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in the methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -CO-O-), an alkanedioxy group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -CO-O-), etc. These replaced groups are R 1 Examples of the replacement of the hydrocarbon group are the same as those exemplified above. X 0 Among the hydrocarbon groups, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include cyclic ethers, cyclic ketones, cyclic esters (lactones), cyclic thioethers, cyclic acetals, cyclic sultones, etc. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding positions of the alicyclic hydrocarbon groups mentioned in the following formulas can be at any position. TIFF2025097300000014.tif50162X 0Among the hydrocarbon groups, -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 and 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 following groups and the like. The bonding site can be at any position. Examples of the group combining two or more of a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group include the group combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, the group combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, the group combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and the group combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group. Examples of the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group may be a condensed ring. X 0 The hydrocarbon group may have a halogen atom or a substituent other than a halogen atom. Examples of the substituent other than a halogen atom include a cyano group and a nitro group. X 0 When X is a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group, substantially, the chain hydrocarbon group can be regarded as a substituent possessed by the alicyclic hydrocarbon group or the aromatic hydrocarbon group. Also, X 0 By replacing -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of X with -O-, -CO-, -S- or -SO2-, the hydrocarbon group of X 0 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, a sulfonyl group and the like. The hydrogen atoms contained in an alkyl group, a carboxyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, and an alkylcarbonyloxy group may be replaced by halogen atoms.

[0016] X 0 Preferably, it is a fluorine atom, an iodine atom, and an aliphatic hydrocarbon group having 2 to 72 carbon atoms having a halogen atom and / or a C1-C6 fluorinated alkyl group (the -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the aliphatic hydrocarbon group may have a substituent other than a halogen atom), a hydrocarbon group having 6 to 72 carbon atoms containing an aromatic hydrocarbon group having 6 to 36 carbon atoms having a halogen atom and / or a C1-C6 fluorinated alkyl group (the -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the hydrocarbon group may have a substituent other than a halogen atom). More preferably, it is a fluorine atom, an iodine atom, and an alicyclic hydrocarbon group having 3 to 36 carbon atoms having a halogen atom and / or a C1-C4 fluorinated alkyl group, an aromatic hydrocarbon group having 6 to 36 carbon atoms having a halogen atom and / or a C1-C4 fluorinated alkyl group, or a group composed of two or more selected from the group consisting of a chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms having a halogen atom and / or a C1-C4 fluorinated alkyl group, and an aromatic hydrocarbon group having 6 to 36 carbon atoms having a halogen atom and / or a C1-C4 fluorinated alkyl group (the alicyclic hydrocarbon group and the chain hydrocarbon group may have a hydroxy group, the aromatic hydrocarbon group may have a hydroxy group, and the -CH2- contained in the alicyclic hydrocarbon group and the chain hydrocarbon group may be replaced by -O- or -CO-). More preferably, it is a group composed of two or more selected from the group consisting of an iodine atom, an alkyl fluoride group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and an aromatic hydrocarbon group having 6 to 36 carbon atoms (the alicyclic hydrocarbon group and the chain hydrocarbon group may have a fluorine atom, an alkyl fluoride group having 1 to 4 carbon atoms, or a hydroxy group, and the aromatic hydrocarbon group may have a fluorine atom, an iodine atom, an alkyl fluoride group having 1 to 4 carbon atoms, or a hydroxy group, and -CH2- contained in the alicyclic hydrocarbon group and the chain hydrocarbon group may be replaced by -O- or -CO-). Examples of the alkyl fluoride group having 1 to 4 carbon atoms include a trifluoromethyl group, a difluoromethyl group, a monofluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, and the like. Also, X 0 may be the following group. TIFF2025097300000016.tif4492[In formula (X 0 -1), nc2 represents an integer from 0 to 6. When nc2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. nc3 represents an integer from 0 to 6, satisfying 1 ≦ nc2 + nc3 ≦ 6. When nc3 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. R c1 and R c2 each independently represent a halogen atom or an alkyl fluoride group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl fluoride group may be replaced by -O- or -CO-. nc4 and nc5 each represent any integer from 0 to 5, and at least one of nc4 and nc5 of 1 or more is 1 or more. L c1 、L c2 and L c3Each independently represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent. W c1 and W c2 Each independently represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and -CH= or -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. ** represents the bonding site with ring W. The total carbon number of each group does not exceed 72. R c1 and R c2 The halogen atoms of are the same halogen atoms as those exemplified by X 0 Also, the alkyl fluoride groups of R c1 and R c2 include alkyl groups in which one or more hydrogen atoms of the alkyl group exemplified by X 0 are replaced by fluorine within the range allowed by the upper limit of the carbon number. L c1 L c2 and L c3 The chain hydrocarbon groups of include the same groups as the chain hydrocarbon groups exemplified by X 0 as long as the upper limit of the carbon number is present. W c1 and W c2 The alicyclic hydrocarbon groups and aromatic hydrocarbon groups of include the same groups as the alicyclic hydrocarbon groups and aromatic hydrocarbon groups exemplified by X 0 as long as the upper limit of the carbon number is allowed. L c1 L c2 and L c3 The substituents that the chain hydrocarbon groups of may have and the alicyclic hydrocarbon groups and aromatic hydrocarbon groups of W c1 and W c2 that may have substituents are X 0Examples of the substituent which the hydrocarbon group may have include the same groups as the substituents exemplified above. R c1 and R c2 are each independently preferably an iodine atom, a fluorine atom, or a C1-C3 perfluoroalkyl group. nc4 is preferably any integer from 1 to 5, nc5 is preferably any integer from 0 to 4, and more preferably any integer from 0 to 3. L c1 L c2 and L c3 are each independently preferably a single bond or a C1-C6 alkanediyl group (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-, and the alkanediyl group may be substituted with a fluorine atom). L c1 and L c2 are each independently preferably a single bond, a methylene group, an ethylene group, or a group in which an ester bond bonded to W c1 is combined with a C1-C3 alkanediyl group, and L c2 is preferably a single bond, a methylene group, an ethylene group, or a group in which an ester bond bonded to W c1 is combined with a C1-C3 alkanediyl group. In formula (X 0 -1), the alicyclic hydrocarbon group and the aromatic hydrocarbon group of W c1 and W c2 are each independently preferably an alicyclic hydrocarbon group and an aromatic hydrocarbon group represented by the following. In the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below, * and ** represent the bonding sites. In the case of W c1 , * represents a hydrogen atom or the bonding site with R c1 , and in the case of W c2 , * represents the bonding site with L c2 . In the case of W c1 , ** represents a hydrogen atom, a substituent, or the bonding site with L c1 , and at least one of ** represents the bonding site with L c1 . In the case of W c2In the case of, ** is a hydrogen atom, R c2 , a substituent, L c3 represents a bonding site with, and at least one of ** is L c3 represents a bonding site with. In addition, in the alicyclic hydrocarbon group represented below, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. When -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, it preferably forms an ether ring, an ester ring (lactone ring), a carbonate ester ring, a sulfonic acid ester ring (sultone ring) or an acetal ring. TIFF2025097300000017.tif36168W c1 and W c2 are each independently a cyclopentane ring, a cyclohexane ring (in the cyclopentane ring and the cyclohexane ring, two -CH2- contained in the cyclopentane ring and the cyclohexane ring may be replaced by -O- or -S- to form an acetal ring or a thioacetal ring.), a norbornane ring (in the norbornane ring, -CH2- contained in the norbornane ring may be replaced by -O- or -S- to form an oxonorbornane ring or a thionorbornane ring.), a norbornanelactone ring, an adamantane ring, an adamantanlactone ring, a benzene ring, a naphthalene ring, and the cyclopentane ring, the cyclopentane ring, the cyclohexane ring, the norbornane ring, the norbornanelactone ring, the adamantane ring, the adamantanlactone ring, the benzene ring, the naphthalene ring may have substituents such as an iodine atom, a fluorine atom, a trifluoromethyl group, a hydroxy group, a methoxy group, an ethoxy group, etc. in addition to R c1 , R c2 and R c3 . W c1is preferably a spirocyclic hydrocarbon group formed by a cyclopentane ring, a cyclohexane ring, a norbornane ring or an adamantane ring and a cyclopentane ring, a cyclohexane ring, a cycloheptane ring or a cyclooctane ring (the spirocyclic hydrocarbon group may have two -CH2- groups contained in the cyclopentane ring, cyclohexane ring, cycloheptane ring or cyclooctane ring replaced by -O- or -S- respectively to form an acetal ring or a thioacetal ring). The cyclopentane ring, the cyclohexane ring, the norbornane ring and the adamantane ring may have substituents such as iodine atom, fluorine atom, trifluoromethyl group, hydroxy group, methoxy group, ethoxy group, etc. other than R c1 In addition, it may have substituents such as iodine atom, fluorine atom, trifluoromethyl group, hydroxy group, methoxy group, ethoxy group, etc.

[0017] Examples of the compound (I) include compounds represented by the following formula. TIFF2025097300000018.tif194161

[0018] The compound (I) contained in the resist composition of the present invention may be at least one kind of the compound represented by the formula (I), and may contain two or more kinds of the compounds represented by the formula (I). The total content of the compound (I) is usually 0.001 to 20% by mass, preferably 0.005 to 15% by mass, more preferably 0.01 to 10% by mass based on the solid content of the resist composition. The compound (I) can be obtained from commercially available compounds or synthesized by conventionally known methods.

[0019] <Acid generator (B)> As the acid generator (B) contained in the resist composition of the present invention, 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, and the like.

[0020] As the acid generator (B), compounds that generate an acid by radiation, such as those described in 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 used alone or in combination of two or more. The acid generator (B) may contain a structural unit having an acid generating function, for example, it may be a resin having the structural unit (a7) described later. Further, 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-mentioned 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.

[0021] As a preferred form of the acid generator (B), salts represented by the formula (B1) (hereinafter sometimes referred to as "acid generator (B1)") and the like can be mentioned. TIFF2025097300000019.tif1391[In the formula, all the symbols are the same as described above.] L b1 As the (nb1 + 1)-valent hydrocarbon group of, from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining two or more of these groups, nb1 hydrogen atoms are removed, and one or more L b2 Groups that bind to can be mentioned. As the chain hydrocarbon group, a group obtained by removing nb1 hydrogen atoms from an alkyl group or an alkenyl group can be mentioned. The alkyl group may be linear or branched, and specifically, X 0 The same groups as those described as the chain hydrocarbon group of can be mentioned. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 20, and even more preferably 1 to 10. As the alicyclic hydrocarbon group, a group obtained by removing nb1 hydrogen atoms from a monocyclic or polycyclic cycloalkyl group can be mentioned. 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. 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, an adamantyl group, and the like. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group, a steroid group (steroid skeleton), and the like. Further, examples of the ring in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one or more cycloalkyl groups 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 contained in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include those represented by the following formula. TIFF2025097300000020.tif28158 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 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 7 to 12. Examples of the aromatic hydrocarbon group include an aryl group from which nb1 hydrogen atoms have been removed. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorene group, and the like. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, more preferably 5 to 10. L b1 When -CH2- contained in the hydrocarbon group of L is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is defined as the number of carbon atoms in 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 the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in the methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in the methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -CO-O-), an alkanedioxy group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -CO-O-), and the like. These replaced groups include those similar to the above-mentioned ones. L b1 Among the hydrocarbon groups, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a cyclic ether, a cyclic ketone, a cyclic ester (lactone), a cyclic thioether, a cyclic acetal, a cyclic sultone, and the like. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding positions of the alicyclic hydrocarbon groups mentioned in the following formulas can be at any positions. TIFF2025097300000021.tif46146L b1Among the hydrocarbon groups, -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 and 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 the present specification within the range where the upper limit of the number of carbon atoms permits. Examples of the group combining two or more of a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group include a group combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, a group combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, a group combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and a group combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group. Examples of the group 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 chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group formed by removing one hydrogen atom from a group combining two or more of these groups, which binds to Y b1 and. L b2 Examples of the divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group combining two or more of these groups of L b1 are groups formed by removing one hydrogen atom from the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and group combining two or more of these groups exemplified by L L b1 and L b2 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, an iodine atom, etc. L b1 and L b2When it is a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group, substantially, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, L b1 and L b2 When the -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of is replaced by -O-, -CO-, -S- or -SO2-, L b1 and L b2 The hydrocarbon groups of can 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, a sulfonyl group and the like. Y b1 Examples of the cyclic hydrocarbon group of include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group and an aromatic hydrocarbon group are combined. Y b1 The alicyclic hydrogen group and the aromatic hydrocarbon group of are the same as the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified by L b1 respectively, and when they have no substituent, they may be a monovalent alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 Examples of the substituent that the methyl group of may have include a halogen atom, a cyano group, a hydroxy group, and a nitro group. Y b1 Examples of the substituent that the cyclic hydrocarbon group of 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. The -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 may have as a substituent include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which these groups are combined. Examples of a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which two or more of these groups are combined include, within the range allowed by the upper limit of the number of carbon atoms, L b1Examples of groups similar to the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group formed by combining two or more of these groups exemplified above, and Y b1 Examples of groups in which -CH2- contained in a hydrocarbon group having 1 to 18 carbon atoms, which may have a cyclic hydrocarbon group of Y b1 as a substituent, is replaced by -O-, -S-, -CO-, or -SO2- are groups similar to the groups exemplified by groups in which -CH2- contained in the hydrocarbon group of Lb1 is replaced by -O-, -S-, -CO-, or -SO2- within the range allowed by the upper limit of the number of carbon atoms. Further, Y 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). TIFF2025097300000022.tif31125 [In formula (B1-A1), L b2 and Y b1 represent the same meaning as in formula (B1). Q b1 Q b2 Q b3 and Q b4 each independently represent 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. X 1 represents -O-CO-, -CO-O-, -O-CO-O-, or -O-. L b3 represents a hydrocarbon group having (nb2 + 1) 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.] Q b1 Q b2 Q b3 and Q b4Examples of the alkyl group represented by the formula (I) 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. Q b1 , Q b2 , Q b3 and Q b4 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms 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, and a perfluorohexyl group. Q b1 and Q b2 Q b1 and Q b2 At least one of the groups preferably contains a fluorine atom or a perfluoroalkyl group, 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. Q b3 and Q b4 are each preferably independently a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b3 is preferably a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b4 is preferably a hydrogen atom or a fluorine atom. z1 is preferably an integer of 0 to 3, and is preferably 0, 1 or 2. X 1 is preferably -O-CO- or -CO-O-.

[0022] L b3 As the hydrocarbon group in the formula (B1), within the range permitted by the upper limit of the number of carbon atoms, b1 The same hydrocarbon groups as those exemplified above are included. In formula (B1-A1), L b3is preferably a linear hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (wherein -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-), 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-, -S-, -CO- or -SO2-), an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent (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, and more preferably a linear hydrocarbon group having 1 to 6 carbon atoms or a group represented by the following formula (Lb3-1). When the linear hydrocarbon group is replaced by -O- or -CO-, the number of -CH2- contained in the linear hydrocarbon group replaced by -O- or -CO- is preferably 1 to 4, and preferably one -CH2-CH2- contained in the linear hydrocarbon group is replaced by -O-CO- or -CO-O-, or -CH2-CH2-CH2- contained in the linear hydrocarbon group is replaced by -O-CO-O-. TIFF2025097300000023.tif1581[In the formula (Lb3-1), nb2 represents the same meaning as the formula (B1-A1). L b31 is a single bond or a linear hydrocarbon group having 1 to 12 carbon atoms, wherein -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO- and 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, wherein -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 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 linear hydrocarbon group, as long as it has an upper limit of the number of carbon atoms, L b1Groups similar to the chain hydrocarbon groups exemplified by the chain hydrocarbon groups exemplified herein can be mentioned. W b3 The alicyclic hydrocarbon groups and aromatic hydrocarbon groups of are, as long as the upper limit of the number of carbon atoms permits, the alicyclic hydrocarbon groups and aromatic hydrocarbon groups exemplified by L b1 can be mentioned. L b31 The substituents that the chain hydrocarbon groups of may have and W b1 The substituents that the alicyclic hydrocarbon groups and aromatic hydrocarbon groups of may have are groups similar to the substituents exemplified as the substituents that the hydrocarbon groups of L b1 can 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, W b1 The alicyclic hydrocarbon groups and aromatic hydrocarbon groups of are preferably the alicyclic hydrocarbon groups and aromatic hydrocarbon groups represented below. In the alicyclic hydrocarbon groups and aromatic hydrocarbon groups represented below, * and ** represent the bonding sites, * represents the bonding site with X 1 or L b31 represents the bonding site with, and ** represents the bonding site with a hydrogen atom, a substituent or L b2 represents the bonding site with, and at least one ** represents the bonding site with L b2 represents the bonding site with. Further, 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 ring) or an acetal ring. In formula (B1-A1) of TIFF2025097300000024.tif37168, L b2is preferably a single bond or an alkanediyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and is preferably a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O- or *-L b21 -X 2 -L b22 -**(L b21 and L b22 either one of them represents an alkanediyl group having at least 1 to 6 carbon atoms, the other represents a single bond or an alkanediyl 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 represents. However, L b21 , X 2 and L b22 The total number of carbon atoms of is 12 or less.) is preferred. Y b1 is preferably 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 group represented by the following formulas (Y1) to (Y36). In the formulas (Y1) to (Y36), R Yb represents an alkyl group having 1 to 4 carbon atoms among the substituents which the cyclic hydrocarbon group of Y b1 may have, R Yc represents a hydrogen atom or a substituent which the cyclic hydrocarbon group of Y b1 may have, and * represents the bonding site with L b2 represents. The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formulas are not particularly shown in the following formulas, but may have other substituents. TIFF2025097300000025.tif83158

[0023] As the anion in the salt represented by formula (B1), anions represented by formula (B1-A1-1) to formula (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 formula (B1-A1-1) to formula (B1-A1-4), formula (B1-A1-9), formula (B1-A1-10), formula (B1-A1-24) to formula (B1-A1-33), formula (B1-A1-36) to formula (B1-A1-40), and formula (B1-A1-47) to formula (B1-A1-85) is more preferable. TIFF2025097300000026.tif216161

[0024] TIFF2025097300000027.tif249151

[0025] TIFF2025097300000028.tif254163

[0026] 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 described above. Specific examples of the anion represented by formula (B1-A1) include the anions described in JP-A-2010-204646.

[0027] Preferable anions in the salt represented by formula (B1) include anions respectively represented by formula (B1a-1) to formula (B1a-70). TIFF2025097300000029.tif186163

[0028] TIFF2025097300000030.tif253166

[0029] TIFF2025097300000031.tif71167

[0030] Among them, anions represented by any of Formula (B1a-1) to Formula (B1a-3), Formula (B1a-7) to Formula (B1a-19), and Formula (B1a-22) to Formula (B1a-70) are preferable.

[0031] The anion represented by Formula (B1-A2) is represented by the following formula. TIFF2025097300000032.tif24100[In Formula (B1-A2), L b2 and Y b1 have the same meaning as in 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 an integer of any one of 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 an integer of any one of 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.]

[0032] In Formula (B1-A2), for the hydrocarbon group of L b2 and the cyclic hydrocarbon group of Y b1 examples are the same as the examples of the hydrocarbon group of L b2 in Formula (B1) and the examples of the cyclic hydrocarbon group of Y b1 within the range allowed by the upper limit of the number of carbon atoms. For the hydrocarbon group of L b2 , the methyl group of Y b1 and the substituents that the cyclic hydrocarbon group may have, for L in Formula (B1) b2The hydrocarbon group, Y b1 Examples of the substituents that the methyl group and the cyclic hydrocarbon group of b1 may have are the same as those exemplified above. L b2 preferably represents an alkanediyl group having 1 to 12 carbon atoms, and -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 -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. *, represents SO3 - 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 18 carbon atoms (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O- or -CO-), more preferably Y of formula (B1-A1) b1 , and further L b1 is the cyclic hydrocarbon group exemplified above, and more preferably the following groups. R Yb and R Yc have the same meanings as described above. TIFF2025097300000033.tif83158

[0033] 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 - . TIFF2025097300000034.tif28107[In the above formula, L b2 , Y b1 , R b1 , nb3 represent the same meanings as in formula (B1-A2).] In formula (B1-A2), when n4b is 2 or more, a plurality of Lb2 and Y b1 preferably represent the same group as each other.

[0034] 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, 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 even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group, or a methyl group. nb3 is any integer from 0 to 4 (that is, nb3 - 1 represents any integer from 0 to 3), preferably any integer from 0 to 3, more preferably any 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. 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.

[0035] Examples of the anion (B1-A2) include, for example, the following anions. Among them, the anions represented by formula (B2a-1) to formula (B2a-20) are preferred, and the anions represented by formula (B2a-1) to formula (B2a-11), formula (B2a-16) to formula (B2a-20) are more preferred. TIFF2025097300000035.tif95162

[0036] In another form of the acid generator (B), an anion in which the anion represented by formula (B1) is replaced with a sulfonimide anion or a sulfonylmethide anion or a carboxylic acid anion is also preferably used as the acid generator (B). Examples of the sulfonylimide anion and the sulfonylmethide anion include the following. TIFF2025097300000036.tif1289[In formula (B1-A3), A 1 represents a nitrogen atom or a carbon atom. L b2’ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced with -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 with -O-, -S-, -SO2- or -CO-, and two -SO2-L b2’ -Y b1’ may combine together to form a ring containing A 1 . nb5 represents 2 or 3. When nb5 is 2, A 1 represents a nitrogen atom, and when nb5 is 3, A 1 represents a carbon atom. The groups in the plurality of parentheses may be the same as or different from each other.] In formula (B1-A3), L b2’ and Y b1’ Examples of the hydrocarbon group, the cyclic hydrocarbon group and their substituents of are the same as those of L b2 and Yb1 include the same group. In formula (B1-A3), L b2’ represents 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 the -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. In formula (B1-A3), 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). nb5 is preferably 2 or 3.

[0037] In formula (B1-A3), when two -SO2-L b2’ -Y b1’ combine together to form a ring containing A 1 for example, an anion represented by formula (B1-A3’) can be mentioned. TIFF2025097300000037.tif21122 [In formula (B1-A3’), A 1 , Y b1 , L b2 , nb5 each represent the same meaning 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 b4The disulfonylimide ring or disulfonylmethide ring 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.

[0038] Examples of the anion represented by the formula (B1-A3) include the following. Among them, the anions represented by the formula (B1-a3-1) and the formula (B1-a3-2) are preferable. TIFF2025097300000038.tif188163Examples of the carboxylic acid anion include the following. TIFF2025097300000039.tif41155

[0039] Z1 + Examples of the organic cation of include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferable, and arylsulfonium cations or aryl iodonium cations are more preferable. Specifically, cations represented by any of the formulas (b2-1) to (b2-5) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number) are included. TIFF2025097300000040.tif82160[In the formulas (b2-1) to (b2-5), R b4 ~R b6Each independently represents an acyclic 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 atoms contained in the acyclic 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, and the hydrogen atoms 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, and the hydrogen atoms 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 the —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 any integer from 0 to 5. When m2 is 2 or more, the plurality of R b7 may be the same or different, and when n2 is 2 or more, the plurality of R b8 may be the same or different. R b9 and R b10 each independently represents an acyclic 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 be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and the —CH2— contained in the ring may be replaced with —O—, —S—, or —CO—. R b11represents 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 a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 and may be bonded to each other to form a ring including -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced with -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 and may be bonded to each other to form a ring containing a sulfur atom together with the benzene ring to which they are bonded, and -CH2- contained in the ring may be replaced with -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 any integer from 0 to 5. q2 and r2 each independently represent any integer from 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, a plurality of R b13are the same or different, and when p2 is 2 or more, a plurality of R b14 are the same or different, and when q2 is 2 or more, a plurality of R b15 are the same or different, and when r2 is 2 or more, a plurality of R b16 are the same or different, and when s2 is 2 or more, a plurality of R b17 are the same or different, and when t2 is 2 or more, a plurality of R b18 are the same or different. u3 represents any integer from 1 to 3 and satisfies 1 ≦ u3 + q23 ≦ 5. u4 and u5 each independently represent any integer from 0 to 3 and satisfy 0 ≦ u4 + o21 ≦ 5 and 0 ≦ u5 + p22 ≦ 5. o21, p22, q23, r24, t25, and s26 each independently represent any integer from 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 at least one of R b13 ~R b16 is preferably a halogen atom. When u2 is 1, any one of o2, p2, s2, t2, q2, and r2 is 1 or more, and at least one of R b13 ~R b18 is preferably a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, more preferably 1. Also, when u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom.

[0040] 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, R b9 ~R b12 The chain hydrocarbon group is preferably a group 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. TIFF2025097300000041.tif11157In particular, R b9 ~R b12 The alicyclic hydrocarbon group is preferably a group having 3 to 18 carbon atoms, more preferably a group having 4 to 12 carbon atoms.

[0041] Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include methylcyclohexyl group, dimethylcyclohexyl group, 2-methyladamantan-2-yl group, 2-ethyladamantan-2-yl group, 2-isopropyladamantan-2-yl group, methylnorbornyl group, and isobornyl group. 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 fluoromethyl group, difluoromethyl group, trifluoromethyl group, and perfluorobutyl. 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.

[0042] Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, biphenyl group, naphthyl group, and 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 tolyl group, xylyl group, cumenyl group, mesityl group, p-ethylphenyl group, p-tert-butylphenyl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc., and examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group include p-cyclohexylphenyl group, p-adamantylphenyl group, etc. 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 preferred. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include p-methoxyphenyl group, etc. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as benzyl group, phenethyl group, phenylpropyl group, trityl group, naphthylmethyl group, naphthylethyl group, etc.

[0043] Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group, dodecyloxy group, etc. Examples of the alkylcarbonyl group include acetyl group, propionyl group, butyryl group, etc. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, iodine atom, etc. Examples of the alkylcarbonyloxy group include methylcarbonyloxy group, ethylcarbonyloxy group, propylcarbonyloxy group, isopropylcarbonyloxy group, butylcarbonyloxy group, sec-butylcarbonyloxy group, tert-butylcarbonyloxy group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyloxy group, 2-ethylhexylcarbonyloxy group, etc.

[0044] Rb4 and R b5 The ring formed by the combination of and together with the sulfur atom to which they are attached may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. Further, the ring containing a sulfur atom includes 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings, and examples thereof include the following rings. * represents a bonding site. TIFF2025097300000042.tif18125

[0045] R b9 and R b10 The ring formed by and together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. Examples thereof include thiolan-1-ium ring (tetrahydrothiophenium ring), thian-1-ium ring, 1,4-oxathian-4-ium ring and the like. R b11 and R b12 The ring formed by and together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. Examples thereof include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring and the like. R b27 ~R b29 Examples of the group containing an acid-labile group of ~ include -R c30 , -CO-O-R c30 or -L c10 -CO-O-R c30 The group represented by (L c10 represents an alkanediyl group having 1 to 6 carbon atoms, and R c30 represents an acid-labile group.). etc. are included. R b27 ~R b29 represents, as an acid-labile group, for example, the group (1) or group (2) described later.

[0046] Among cations (b2-1) to (b2-5), preferably, they are cation (b2-1), cation (b2-4) or cation (b2-5). Examples of cation (b2-1) include the following cations. TIFF2025097300000043.tif150165 Examples of cation (b2-2) include the following cations. TIFF2025097300000044.tif14136 Examples of cation (b2-3) include the following cations. TIFF2025097300000045.tif21130 Examples of cation (b2-4) include the following cations. TIFF2025097300000046.tif122162 Examples of cation (b2-5) include the following cations. TIFF2025097300000047.tif114158

[0047] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. Examples of the acid generator (B) preferably include any anion 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).

[0048] As the acid generator (B), 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 preferably 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. TIFF2025097300000048.tif174167

[0049] TIFF2025097300000049.tif251160

[0050] TIFF2025097300000050.tif254165

[0051] TIFF2025097300000051.tif252160

[0052] TIFF2025097300000052.tif249163

[0053] TIFF2025097300000053.tif247150

[0054] TIFF2025097300000054.tif184159

[0055] In the resist composition of the present invention, the content of the acid generator (B) is 1% by mass or more and 45% by mass or less, preferably 1% by mass or more and 40% by mass or less, more preferably 3% by mass or more and 35% by mass or less, based on the solid content of the resist composition. Further, when the resist composition of the present invention contains the resin (A) described later, the content of the acid generator (B) is preferably 1 part by mass or more and 45 parts by mass or less, more preferably 1 part by mass or more and 40 parts by mass or less, still more preferably 3 parts by mass or more and 35 parts by mass or less, per 100 parts by mass of the resin (A).

[0056] <Resin (A)> Resin (A) contains a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)"). Resin (A) preferably further contains a structural unit other than structural unit (a1). Examples of the structural unit other than structural unit (a1) include a structural unit having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)"), a structural unit other than structural unit (a1) and structural unit (s) (for example, a structural unit having a halogen atom described later (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group described later (hereinafter sometimes referred to as "structural unit (a5)"), and a structural unit derived from other monomers known in the art, etc.).

[0057] 〈Structural unit (a1)〉 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 Resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF2025097300000055.tif2298[In 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 group combining these, 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.] TIFF2025097300000056.tif2278[In formula (2), R a1’ and Ra2’ 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-. 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.]

[0058] R a1 、R a2 and R a3 Examples of the alkyl group in R 、R a1 、R a2 and R a3 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, etc. R a1 、R a2 and R a3 The alicyclic hydrocarbon group in R a1 、R a2 and R a3 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.). The carbon number of the alicyclic hydrocarbon group of R TIFF2025097300000057.tif10159R a1 、R a2 and Ra3 Examples of the aromatic hydrocarbon group in [the compound] include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, and phenanthryl group. Examples of the combined group include groups formed by combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), aralkyl groups such as benzyl group, aromatic hydrocarbon groups 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 groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. Preferably, ma is 0 and na is 1. R a1 and R a2 When R a1 and R a2 and R a3 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-. TIFF2025097300000058.tif27138

[0059] R a1’ R a2’ and R a3’ Examples of the hydrocarbon group in R a1’ R a2’ and R a3’ include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and the group formed by combining these are the same as the groups exemplified for R a1 R a2 and R a3 . R a2’ and Ra3’ When they 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 groups. * represents a bond. TIFF2025097300000059.tif19124R a1’ and R a2’ Among them, at least one 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

[0060] Group (1) includes the following groups. In formula (1), R a1 、R a2 and R a3 are alkyl groups, ma = 0, and na = 1. As such a group, a tert-butoxycarbonyl group is preferable. In formula (1), R a1 、R a2 together with the carbon atom to which they are bonded form an adamantyl group, 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 group (1) include the following groups. * represents a bond. TIFF2025097300000060.tif150162

[0061] Specific examples of group (2) include the following groups. * represents a bond. TIFF2025097300000061.tif55153

[0062] 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 preferred. If a resin (A) 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.

[0063] Examples of the structural unit derived from the (meth)acrylic monomer having group (1) include a structural unit represented by formula (a1-0) (hereinafter sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter sometimes referred to as structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of structural unit (a1-0), structural unit (a1-1), and structural unit (a1-2), more preferably at least one or two structural units selected from the group consisting of structural unit (a1-1) and structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2025097300000062.tif44144[In formula (a1-0), formula (a1-1), and formula (a1-2), all symbols have the same meanings as described above.]

[0064] R a01 、R a4 and R a5 The halogen atoms in are fluorine atom, chlorine atom, bromine atom, or iodine atom. R a01 、R a4 and R a5Examples of the alkyl group which may have a halogen atom include 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, chloromethyl group, bromomethyl group, and iodomethyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, and still 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 are preferably a hydrogen atom or a methyl group, and more preferably a methyl group. L a01 、L a1 and L a2 are preferably an oxygen atom or *-O-(CH2) k01 -CO-O- (wherein k01 is preferably any integer from 1 to 4, and more preferably 1), and more preferably an oxygen atom. R a02 、R a03 、R a04 、R a6 and R a7 Examples of the halogen atom, alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group and the group formed by combining these in R a1 、R a2 and R a3 are the same groups as those exemplified for R R a02 、R a03 、and R a04 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and still more preferably a methyl group. R a6and R a7 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 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 Ra7 is 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.

[0065] 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), and formulas (a1-0-19) to (a1-0-21) are preferred. a01 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. TIFF2025097300000063.tif119160

[0066] 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 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. TIFF2025097300000064.tif35169

[0067] Examples of the structural unit (a1-2) include a structural unit represented by any 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. Among them, the structural units represented by any of Formula (a1-2-2), Formula (a1-2-5), Formula (a1-2-6), and Formula (a1-2-10) to Formula (a1-2-20) are preferable. a5 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, and still even more preferably 40 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 70 mol% or less, and 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%. TIFF2025097300000065.tif91163

[0068] 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, and still even more preferably 30 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, and more preferably 70 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 with respect to all the structural units of 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 90 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, still more preferably 20 to 80 mol%, even more preferably 20 to 75 mol%, and still even more preferably 20 to 70 mol%.

[0069] Examples of the structural unit having the group (2) in the structural unit (a1) include a structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as "structural unit (a1-4)"). TIFF2025097300000066.tif31118[In the formula (a1-4), all the symbols have the same meanings as described above.]

[0070] R a1 and R a17 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R a01 are the same as those exemplified by R of the formula (a1-0). 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 still more preferably a hydrogen atom or a methyl group. R a17Examples of the alkoxy group in [compound name] include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, and 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, still more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a17 Examples of the alkoxyalkyl group in [compound name] include methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and tert-butoxymethyl group. The alkoxyalkyl group may be an alkoxyalkyl group having 2 to 8 carbon atoms, preferably an alkoxyalkyl group having 2 to 4 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and still more preferably a methoxymethyl group. R a17 Examples of the alkoxyalkoxy group in [compound name] include methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, ethoxyethoxy group, propoxymethoxy group, isopropoxymethoxy group, butoxymethoxy group, sec-butoxymethoxy group, and 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, still more preferably a methoxyethoxy group or an ethoxyethoxy group. R a17 Examples of the alkylcarbonyl group in [compound name] include acetyl group, propionyl group, and butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 4 carbon atoms, more preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and still more preferably an acetyl group. R a17 Examples of the alkylcarbonyloxy group in [compound name] include acetyloxy group, propionyloxy group, and butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 4 carbon atoms, more preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and still more preferably an acetyloxy group. R a17is 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.

[0071] A a11 Examples of the alkanediyl group of 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 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-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, undecane-1,10-diyl group, etc. 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 even more preferably 1 to 3, and even more preferably 1 or 2. R a18 Examples of the alkyl group of include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group. A a11 When -CH2- contained in the alkanediyl group of is replaced by -O-, -CO- or -NR a18 -, the number of carbon atoms before replacement is taken as the number of carbon atoms of the alkanediyl group. A a11 When -CH2- contained in the alkanediyl group of is replaced by -O-, -CO- or -NRa18 - as the replaced group, there are a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group (wherein -CH2- contained in the methyl group is replaced by -NR a18 - group), an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylamino group (wherein any -CH2- contained in the alkyl group is replaced by -NR a18 - group), a peptide group (wherein -CH2-CH2- contained in the ethylene group is replaced by -CO-NR a18 - group), an alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediyl-carbonyl group, an alkanediyl-carbonyl-oxy group, an alkanediyl-sulfonyl group, an alkanediyl-thio group, an alkanediyl-amino group (wherein any -CH2- contained in the alkanediyl group is replaced by -NR a18 - group), etc. These replaced groups include those similar to those exemplified herein within the range allowed by the upper limit of the number of carbon atoms. Examples of the alkylamino group include alkylamino 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, an octylamino group, etc. The number of carbon atoms of the alkylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms of 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 - as the group in which -CH2- contained in the alkanediyl group of is replaced by -O-, -CO- or -NR a18 - group, there are *-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 - includes. Among them, *-CO-O-, *-CO-O-A a12 -CO-O-, *-O-A a12 -CO-O-, *-CO-NR a18 - is preferred. Here, A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site with the carbon atom to which R a1 is bonded. The alkanediyl group of A a12 includes alkanediyl groups similar to A within the range allowed by the upper limit of the number of carbon atoms. A a11 is a single bond, *-CO-O- or *-CO-O-A a12 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. na1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na11 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.

[0072] R a34 、R a35 and R a36 The hydrocarbon groups in include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups and groups combining these. Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, 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 cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents the bonding site). Examples of the aromatic hydrocarbon group 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 groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group and the like), aralkyl groups such as benzyl group, aromatic hydrocarbon groups 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 and the like), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group and the like), aryl-cycloalkyl groups such as phenylcyclohexyl group and the like. In particular, R a36 Examples thereof 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 a36 Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms formed by R and R bonding to each other together with the -C-O- to which they are bonded include, for example, the following groups. * represents the bonding site, and one side is the bonding site with R a34 TIFF2025097300000068.tif15105

[0073] 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, 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, 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 the 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.

[0074] -OC(R a34 )(R a35 )-O-R a36 in the structural unit (a1-4) eliminates upon contact with an acid (for example, p-toluenesulfonic acid) to form a hydroxy group or a carboxy group. -X a1 -O-C(R a34 )(R a35 )-O-R a36 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 a11 . Among them, it is preferable that at least one is 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 when the bonding position of A a11 is at the 2nd position, it may be bonded to any of the 1st and 3rd to 8th positions. Among them, when the bonding position of A a11 is at the 1-position, it is preferable that at least one is bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. When the bonding position of A a11 is at the 2nd position, it is preferable that it is bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0075] 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 formula (a1-4-1) to formula (a1-4-42) and the hydrogen atom corresponding to R in the structural unit (a1-4) a1 are replaced by a halogen atom, a haloalkyl group or an alkyl group, and more preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-5), formula (a1-4-10), formula (a1-4-13), formula (a1-4-14), formula (a1-4-19), and formula (a1-4-20). When the resin (A) contains the structural unit (a1-4), its 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).

[0076] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) also include the structural unit represented by formula (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)"). TIFF2025097300000070.tif4558[In formula (a1-5), all the symbols have the same meanings as described above.]

[0077] R a8 Examples of the halogen atom in R and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom are the same as those exemplified for R of formula (a1-0). a01 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-. For s1, 1 is preferable. For s1', any integer from 0 to 2 is preferable. Z a1 is preferably a single bond or *-CH2-CO-O-.

[0078] 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), its content 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 still 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 still 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 still more preferably.

[0079] Examples of the structural unit having the group (1) in the structural unit (a1) include the structural unit represented by Formula (a1-6) (hereinafter sometimes referred to as "structural unit (a1-6)"). TIFF2025097300000072.tif3481[In Formula (a1-6), all the symbols have the same meanings as described above.]

[0080] R a61Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in (a1-0) include the same ones as those exemplified by R in a01 and the like. 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 and the like. 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 still more preferably a methyl group or an ethyl group. R a62 、R a63 and R a64 Examples of the cyclic hydrocarbon group in include 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. TIFF2025097300000073.tif32110

[0081] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in 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 butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group and the like. L a61 and L a62 are each independently preferably a methylene group or an ethylene group. X a61is 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.

[0082] Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, 1-naphthylene group, 2-naphthylene group, 1-anthrylene group, 9-anthrylene group, biphenylene group, 1-phenanthrylene group, 2-phenanthrylene group, and the like. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, hydroxy group, alkyl 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.

[0083] Examples of the halogen atom include a fluorine atom, iodine atom, chlorine atom, bromine atom, and the like. Examples of the alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, and 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, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, and 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. Preferred substituents 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 preferred are 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 preferred are 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.

[0084] 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, 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. TIFF2025097300000074.tif227164

[0085] In the structural units represented by Formula (a1-6-1) to Formula (a1-6-9), Formula (a1-6-16) to Formula (a1-6-21), Formula (a1-6-28) to Formula (a1-6-30), and Formula (a1-6-37) to Formula (a1-6-43), R a61 Structural units in which the hydrogen atom corresponding to is replaced by a methyl group, a halogen atom, a haloalkyl group, etc., and in the structural units represented by Formula (a1-6-10) to Formula (a1-6-15), Formula (a1-6-22) to Formula (a1-6-27), and Formula (a1-6-31) to Formula (a1-6-36), R a61 Structural units in which the methyl group corresponding to is replaced by a hydrogen atom, a halogen atom, a haloalkyl group, etc. are also included as the structural unit (a1-6).

[0086] 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, still more preferably 10 mol% or more, even 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, still more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 65 mol%.

[0087] Moreover, as the structural unit (a1), the following structural units are also included. TIFF2025097300000075.tif33167

[0088] When the resin (A) etc. contains the structural units represented by the formulas (a1-7-1) to (a1-7-7), 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) etc. 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, it is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol%.

[0089] Moreover, as the structural unit (a1), the following structural units are also included. When resin (A) etc. contain structural units represented by formulas (a1-8-1) to (a1-8-3), 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, based on all the structural units of resin (A) etc. 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.

[0090] 〈Structural unit(s)〉 The structural unit(s) is / are derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer(s)"). As the monomer that leads to the structural unit(s), 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)"), or a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"), and the like.

[0091] 〈Structural unit (a2)〉 The structural unit (a2) is a structural unit represented by the formula (a2) and has an alcoholic hydroxy, phenolic hydroxy group or carboxy group. TIFF2025097300000077.tif4194[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 a chain hydrocarbon group having 1 to 12 carbon atoms which may have a single bond or a fluorine atom, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. na2 represents any integer from 1 to 5. When na2 is any integer of 2 or more, a plurality of Ls a22 may be the same as or different from each other.

[0092] R a2 Examples of the halogen atom in R include a fluorine atom, an iodine atom, a chlorine atom, a bromine atom and the like. 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. 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.

[0093] 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, 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, 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-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, undecane-1,10-diyl group. The number of carbon atoms in the alkanediyl group is preferably 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 even 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, and tert-butyl group. A a21 When -CH2- contained in the alkanediyl group of A is replaced by -O-, -CO- or -NR a28 , the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group. A a21 Examples of the group in which -CH2- contained in the alkanediyl group of 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 allowed by the upper limit of the number of carbon atoms. For example, A a21 The -CH2- contained in the alkanediyl group of, when 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 with 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 allowed by the upper limit of the number of carbon atoms. 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-.

[0094] 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. Also, examples thereof 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 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. L a21 Examples of the monocyclic and polycyclic divalent alicyclic hydrocarbon groups in L include the following alicyclic hydrocarbon groups and the like. The bonding site can be at any position. TIFF2025097300000078.tif46168For example, divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanpentyl group, and a cyclohexanhexyl group 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, and 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, etc. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced by a bonding site, etc. 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, even more preferably 3 to 12, still even more preferably 6 to 12, and particularly preferably 6 to 10. L a21 Examples of the aromatic hydrocarbon group in include divalent to hexavalent aromatic hydrocarbon groups such as an arylene group, an arenetricyl group, an arenetetrayl group, an arenepentayl group, an arenexayl group, etc. Specifically, 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, a phenanthrenetetrayl group, etc. can be mentioned. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced by a bonding site, etc. 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, even more preferably 6 to 12, and still even more preferably 6 to 10. Examples of the group formed by combining two or more of them 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 of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined with each other. Also, any of the groups may be bonded to A a21 and L a22 . Examples of the trivalent to pentavalent alicyclic hydrocarbon group and aromatic hydrocarbon group include groups formed by removing 1 to 3 hydrogen atoms from the above-described divalent groups to form bonds. 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 those similar to the groups exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms.

[0095] 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 allowed by the upper limit of the number of carbon atoms. Examples of the group in which -CH2- contained in the combined group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. The bonding site can be at any position. TIFF2025097300000079.tif26164L 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 (the -CH2- contained in the haloalkyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. 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, etc. 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 includes a branched structure, so that L a21can 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 in 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 still more preferably 1 to 3. L a21 The -CH2- contained in the hydrocarbon group of L is replaced by a group such as -O-, -CO-, -S- or -SO2-. a21 L a21 can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, a thiol group, a sulfonyl group, an alkoxyalkyl group, an alkoxyalkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, and the like. The number of carbon atoms in the alkoxy group is preferably 1 to 12, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. The number of carbon atoms in the alkoxycarbonyl group, the alkylcarbonyl group, and the alkylcarbonyloxy group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 to 3. The number of carbon atoms in the alkoxyalkyl group and the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 8, still more preferably 2 to 6, and even more preferably 2 to 4. These groups include those similar to those exemplified in this specification. L a21Examples of the substituent that the hydrocarbon group in [compound name] may have include a halogen atom, a haloalkyl group having 1 to 8 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-). A halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-) is more preferable. 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-) is even more preferable. 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-) is still more preferable. A fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group is yet more preferable. Also, when a21 the alkanediyl group of L a23 is replaced by -O-, -CO-, etc., for example, *-L a21 -X a23 - (L a21 represents an alkanediyl group having 1 to 8 carbon atoms, X a21 represents -O-, -O-CO-, -CO-O-, or -O-CO-O-, and * represents the bonding site with A 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-).

[0096] 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 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 number of carbon atoms of the chain hydrocarbon group 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 the same as those exemplified in this specification. L a22 The fluorine atom that L has may be one or two or more. na2 is preferably any integer from 1 to 4, and more preferably any integer from 1 to 3. 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. TIFF2025097300000080.tif67163

[0097] 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. The structural unit (a2) may be contained alone or in combination of two or more.

[0098] In the structural unit (a2), L a21 When 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)"). TIFF2025097300000081.tif30128 [In the formula (a2-A), all the symbols have the same meanings as described above.]

[0099] R a2 and A a21 are each a group similar to those exemplified in the formula (a2). R a27 Examples of the halogen atom of R include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom. R a27Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include 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, chloromethyl group, bromomethyl group, and 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 a27 Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, and tert-butoxy group. The number of carbon atoms of 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 methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and 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 methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, ethoxyethoxy group, propoxymethoxy group, isopropoxymethoxy group, butoxymethoxy group, sec-butoxymethoxy group, and 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. R a27Examples 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. 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, and more preferably an acetyloxy group. R a27 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 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 may be 1, 2, 3, or 4, preferably 1, 2, or 3, and more preferably 1 or 2. na21 is preferably 0, 1, or 2, and 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 2nd to 8th positions, and when the bonding position of A a21 is at the 2nd position, it may be bonded to any of the 1st and 3rd to 8th positions. Among them, when the bonding position of A a21 is at the 1st position, at least one is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. When the bonding position of A a21 is at the 2nd position, it is preferably bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0100] Examples of the structural unit (a2-A) include structural units derived from 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) and formula (a2-3-1) to formula (a2-3-24), and in the structural units represented by formula (a2-2-1) to formula (a2-2-32) and formula (a2-3-1) to formula (a2-3-24), the methyl group corresponding to R a2 in the structural unit (a2-A) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2025097300000082.tif107170

[0101] 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, and 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) is a compound that induces the structural unit (a2-A) (for example, -CH2-C(-R a2 )- of the structural unit (a2-A) is CH2=C(-R of the double bond before cleavage a2By polymerizing a compound (such as (a2-A’)) in the state of ), it can be incorporated into the resin (A). 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.

[0102] 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 the formula (a2-B) (hereinafter sometimes referred to as “structural unit (a2-B)”), a structural unit represented by the formula (a2-C) (hereinafter sometimes referred to as “structural unit (a2-C)”), or a structural unit represented by the formula (a2-D) (hereinafter sometimes referred to as “structural unit (a2-D)”). TIFF2025097300000084.tif45100[In the formula (a2-B) and the formula (a2-C), R a2 represents the same meaning as in the formula (a2). R a27 represents the same meaning as in the formula (a2-A). L a25 represents -O- or *-O-(CH2) k2 -CO-O-, k2 represents an integer of 1 to 7. * represents the bonding position with -CO-. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents an integer of 1 to 5. When nB2 is 2 or more, a plurality of Xs a2 may be the same as or different from each other. nB22 represents an integer of 0 to 8. When nB22 is 2 or more, a 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, a plurality of R 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 a2 is 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.

[0103] 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 R in the following structural units a2Examples of the structural unit in which the methyl group or hydrogen atom corresponding to it is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group include those represented by Formula (a2-B-1) to Formula (a2-B-5) and Formula (a2-C-1) to Formula (a2-C-9). 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. TIFF2025097300000085.tif80164When 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, it is 1 to 45 mol%, 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%.

[0104] Examples of the structural unit having an alcoholic hydroxy group in the structural unit (a2) include the structural unit represented by Formula (a2-D) (hereinafter sometimes referred to as "structural unit (a2-D)"). TIFF2025097300000086.tif51106[In Formula (a2-D), R a2 and A a21 each represent the same meaning as in Formula (a2). R a27 represents the same meaning as in Formula (a2-A). R a21 and R a22 each independently represent a fluoroalkyl 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 a 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, a plurality of Rs a27 may be the same as or different from each other. However, 1 ≦ nD2 + nD22 ≦ 5.] R a21 and R a22 Examples of the C1-C4 fluoroalkyl groups for R and R a21 include, independently of each other, a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, etc. a22 As R and R a24 a trifluoromethyl group is preferred. Examples of the alkanediyl group for L a24 include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, etc. As L a27 a single bond or a methylene group is preferred. nD2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, still more preferably 1 or 2, and even more preferably 1. Also preferably, nD2 is 1 and the group in parentheses is bonded at the para position. nD22 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2, still more preferably 0 or 1, and even more preferably 0.

[0105] As the structural unit (a2-D), it is more preferable that it is a structural unit represented by the following formula (a2-D1) (hereinafter, may be referred to as "structural unit (a2-D1)"). TIFF2025097300000087.tif51107[In formula (a2-D1), R a2 、A a21 、R a27 、na2 and na21 represent the same meaning 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.

[0106] Examples of the structural unit (a2-D) include the structural units described below. TIFF2025097300000088.tif62167In the structural units represented by formula (a2-D-1) to formula (a2-D-8), the structural units in which the hydrogen atom corresponding to R a2 is replaced by a methyl group or the like, and in the structural units represented by formula (a2-D-9) to formula (a2-D-16), the structural units 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 preferable, the structural units represented by formula (a2-D-1) to formula (a2-D-4) are more preferable, and the structural unit represented by formula (a2-D-1) is even more preferable.

[0107] 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 with respect to 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%.

[0108] 〈Structural unit (a3)〉 The lactone ring possessed by the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an adamantanlactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)) can be mentioned.

[0109] 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. TIFF2025097300000089.tif51164[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 site with the carbonyl group. R a18 、R a19 、R a20 and R a24 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a3represents -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 any integer from 0 to 5. q1 represents any integer from 0 to 3. r1 represents any integer from 0 to 3. w1 represents any integer from 0 to 8. When p1, q1, r1 and / or w1 is 2 or more, a plurality of R a21 、R a22 、R a23 and / or R a25 may be the same as or different from each other.

[0110] R a21 、R a22 、R a23 and R a25 Examples of the aliphatic hydrocarbon group in R R a18 、R a19 、R a20 and R a24 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 a01 include the same ones as those exemplified by R of formula (a1-0) L a8 and L a9Examples of the alkanediyl group in the formula (I) 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 pentane-1,5-diyl group, a hexane-1,6-diyl group, 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. L a4 ~L a6 are each independently preferably -O- or *-O-(CH2) k3 In the -CO-O- group, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and further preferably an oxygen atom. L a7 is preferably -O- or *-OL a8 -CO-O-, and more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. R a18 , R a19 , 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 even more preferably a hydrogen atom or a methyl group. R a21 is preferably a methyl group. R a22 , R a23 and R a25 are each independently preferably a carboxy group, a cyano group, or a methyl group. p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1. w1 is preferably an integer of 0 to 2, and more preferably 0 or 1. In particular, the formula (a3-4) is preferably the formula (a3-4)'. TIFF2025097300000090.tif4051 (in the formula, R a24 , L a7 has the same meaning as above.)

[0111] 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 said structural units, R in formula (a3-1) to formula (a3-4) a18 , R a19 , R a20 and R a24 structural units in which the methyl groups corresponding to are replaced with hydrogen atoms are preferred. When the resin (A) contains the structural unit (a3), the total content thereof is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 10 mol% or more, based on all the structural units of the resin (A). Further, it is 70 mol% or less, 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, still more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, it is 1 to 70 mol%, preferably 1 to 65 mol%, more preferably 1 to 60 mol%, still more preferably 3 to 60 mol%. In addition, the content ratio 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, respectively, based on all the structural units of the resin (A). Further, 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 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.

[0112] 〈Structural unit (a4)〉 The structural unit represented by the formula (a4) is shown below. TIFF2025097300000092.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-.

[0113] R 42 Examples of the aliphatic hydrocarbon group represented by include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these. 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 a monocyclic alicyclic hydrocarbon group which is a monocyclic cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group; and a polycyclic alicyclic hydrocarbon group which is a polycyclic cycloalkyl group such as a decahydronaphthyl group, an adamantyl group, a norbornyl group and the following group (* represents a bonding site). Examples of the group formed by the combination of TIFF2025097300000093.tif10146 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 a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group; and branched alkanediyl groups such as a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a 1-methylbutane-1,4-diyl group, a 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 the aliphatic hydrocarbon group contained in R include a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. R 42 Examples of the group in which -CH2- of the aliphatic hydrocarbon group contained in R 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 alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, a cycloalkoxy group, a cycloalkylalkoxy group, a group formed by combining two or more of these groups, etc. These replaced groups include the same groups as those exemplified in this specification within the range where the upper limit of the number of carbon atoms permits.

[0114] As the structural unit (a4), R 42 is preferably an aliphatic hydrocarbon group having a fluorine atom, and R 42 Examples of the structural unit (a4) in which 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. TIFF2025097300000094.tif3092[In the formula (a4-1), R 41 represents a hydrogen atom or a methyl group. L 41 represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 42f represents an alkanediyl group having 1 to 8 carbon atoms having a fluorine atom or a cycloalkanediyl group having 3 to 12 carbon atoms having a fluorine atom. R 42f represents a hydrogen atom or a fluorine atom.]

[0115] L 41 Examples of the alkanediyl group in include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. The terminal of the branched alkanediyl group may be a methyl group. L 42fExamples of the alkanediyl group having a fluorine atom in [specific context] include linear alkanediyl groups having a fluorine atom such as a methylene group having a fluorine atom, an ethylene group having a fluorine atom, a propane-1,3-diyl group having a fluorine atom, a butane-1,4-diyl group having a fluorine atom, a pentane-1,5-diyl group having a fluorine atom, a hexane-1,6-diyl group having a fluorine atom, a heptane-1,7-diyl group having a fluorine atom, an octane-1,8-diyl group having a fluorine atom; branched alkanediyl groups having a fluorine atom such as an ethane-1,1-diyl group having a fluorine atom, a propane-1,1-diyl group having a fluorine atom, a propane-1,2-diyl group having a fluorine atom, a propane-2,2-diyl group having a fluorine atom, a pentane-2,4-diyl group having a fluorine atom, a 2-methylpropane-1,3-diyl group having a fluorine atom, a 2-methylpropane-1,2-diyl group having a fluorine atom, a pentane-1,4-diyl group having a fluorine atom, a 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 [specific context] include monocyclic cycloalkanediyl groups such as a cyclobutane-1,3-diyl group having a fluorine atom, a cyclopentane-1,3-diyl group having a fluorine atom, a cyclohexane-1,4-diyl group having a fluorine atom, a cyclohexene-3,6-diyl group having a fluorine atom, a cyclooctane-1,5-diyl group having a fluorine atom, and polycyclic cycloalkanediyl groups having a fluorine atom such as 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, an adamantane-2,6-diyl group having a fluorine atom. L 42f The number of fluorine atoms of the alkanediyl group and cycloalkanediyl group having a fluorine atom in [specific context] may be 1 or more, and is preferably 2 or more. L42f The alkandiyl group and the cycloalkandiyl group having a fluorine atom in are preferably a perfluoroalkandiyl group and a perfluorocycloalkandiyl group, respectively.

[0116] L 42f Examples of the perfluoroalkandiyl 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, a perfluorooctane-4,4-diyl group, and the like. L 42f Examples of the perfluorocycloalkandiyl group in include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, a perfluoroadamantanediyl group, and the like.

[0117] L 41 is preferably a single bond or an alkandiyl group having 1 to 3 carbon atoms, more preferably a single bond, a methylene group or an ethylene group, and still more preferably a single bond or a methylene group. L 42fis 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 still more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0118] Examples of the structural unit (a4-1) include the structural units shown below and the structural units in the structural unit (a4-1) in the following structural units where the methyl group corresponding to R 41 is replaced by a hydrogen atom. The structural unit represented by the formula (a4-2) is the structural unit shown below. TIFF2025097300000096.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 by -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 by -O- or -CO-. However, at least one of L 43f and R 43f has a fluorine atom, and the upper limit of the total carbon number of L 43f and R 43f is 21.]

[0119] 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. Examples of the aliphatic hydrocarbon group in L 43f and R 43f are, as long as the upper limit of the total carbon number of L 43f and R 43f allows, R in the formula (a4)42 Examples of the aliphatic hydrocarbon group of

[0120] L 43f include, as the aliphatic hydrocarbon group of TIFF2025097300000097.tif14120[in 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 of 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

[0121] Examples of the divalent aliphatic hydrocarbon group represented by L 45f , L 46f and L 47f in the group represented by formula (L43f-1) 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, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, etc. are included. ​s is preferably 0.

[0122] 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 -O-CO-R 43f and is the bonding site with -O-CO-R. TIFF2025097300000098.tif47140

[0123] R 43f is preferably an aliphatic hydrocarbon group having a fluorine atom. In this case, examples of the structural unit represented by formula (a4-2) include the structural units represented by formula (a4-2A) or (formula a4-2B). TIFF2025097300000099.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 ** represents the bonding site with A 43f and represents the bonding site with A. R 43fB represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, in formula (a4-2A), the total number of carbon atoms of L 43f and R 43fA is 21 or less, and in formula (a4-2B), the total number of carbon atoms of L 43f , A 43f , X 43 and R 43fB is 21 or less, and at least one of A 43f and R 43fB has at least one fluorine atom. R 43fA The aliphatic hydrocarbon group of R, as long as the upper limit of the number of carbon atoms permits, is an aliphatic hydrocarbon group similar to the aliphatic hydrocarbon group exemplified by R 42 and includes the same aliphatic hydrocarbon groups as those exemplified for the aliphatic hydrocarbon group of R R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and having fluorine atoms, a cycloalkyl group having 3 to 12 carbon atoms and having fluorine atoms, or a group combining them, *-(CF2) n43f -R 42’ (* represents the bonding 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 the aliphatic hydrocarbon group of R, as long as the upper limit of the number of carbon atoms permits, is an aliphatic hydrocarbon group similar to the aliphatic hydrocarbon group exemplified by R in formula (a4) 43fB and includes the same aliphatic hydrocarbon groups as those exemplified for the aliphatic hydrocarbon group of R 42 in formula (a4). A 43f is preferably a divalent chain hydrocarbon group which may have fluorine atoms, a divalent alicyclic hydrocarbon group, or a group combining them, more preferably a divalent chain hydrocarbon group having fluorine atoms, 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 even more preferably 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 heptyl group, a perfluoroheptyl group, an octyl group, a perfluorooctyl group and other alkyl fluoride groups, a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, an adamantyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, a perfluoroadamantylmethyl group and the like.

[0124] 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). TIFF2025097300000100.tif15170

[0125] Examples of the structural unit represented by formula (a4-2A) include 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 are mentioned. TIFF2025097300000101.tif99167

[0126] Examples of the structural unit represented by formula (a4-2B) 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 represented by formula (a4-2B) is replaced by a hydrogen atom. 41 include structural units in which the methyl group corresponding to R in the structural unit represented by formula (a4-2B) is replaced by a hydrogen atom. TIFF2025097300000102.tif111163

[0127] Examples of the structural unit (a4) also include the structural unit represented by formula (a4-3). TIFF2025097300000103.tif3689[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 by -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 by -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.]

[0128] L 44f and R 44f Examples of the aliphatic hydrocarbon group in include linear or branched chain aliphatic hydrocarbon groups and monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these. L 44f and R 44f Examples of the aliphatic hydrocarbon group in are, as long as the upper limit of the total number of carbon atoms of L 44f and R 44f allows, 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 (wherein 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 and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, an alicyclic hydrocarbon group having 3 to 10 carbon atoms and having a fluorine atom, or a group combining them, still more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0129] 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 TIFF2025097300000104.tif86170

[0130] Examples of the structural unit (a4) also include a structural unit represented by the formula (a4-A). TIFF2025097300000105.tif3686 [In the formula (a4-A), all symbols represent the same meaning as described above.]

[0131] R 1 ​The alkyl group having 1 to 6 carbon atoms in [[]] 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 [[]] 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 [[]] 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 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 even more preferably a hydrogen atom or a methyl group.

[0132] L 1 Examples of the aliphatic hydrocarbon group in [[]] include a chain hydrocarbon group, and an alicyclic hydrocarbon group which is monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.). 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 a chain hydrocarbon group such as an alkanediyl 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, 2-methylbutane-1,4-diyl group, etc. 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.

[0133] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups, etc. The bonding site can be at any position. TIFF2025097300000106.tif45164 For example, alicyclic hydrocarbon groups such as cycloalkanediyl group, etc. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, etc. 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 each of a norbornyl group or an adamantyl group. 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.

[0134] Examples of the group formed by combining two or more types include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups and chain hydrocarbon groups may be combined respectively. Also, any of the groups may be bonded to X 11 It may be bonded to. Examples of the group formed by 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 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-), 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 a chain hydrocarbon group, an alicyclic 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 an alicyclic 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.

[0135] 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.

[0136] 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, or an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the alkyl group 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 groups having 1 to 4 carbon atoms include fluoroalkyl groups having 1 to 4 carbon atoms, chloroalkyl groups having 1 to 4 carbon atoms, bromoalkyl groups having 1 to 4 carbon atoms, iodoalkyl groups having 1 to 4 carbon atoms, and the like. Examples of the haloalkyl group include perfluoroalkyl groups having 1 to 4 carbon atoms (such as trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, and 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, 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 methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, 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 total 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 hydroxy group, carboxy group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, alkoxycarbonyloxy group, and the like. L 1 The substituent that the aliphatic hydrocarbon group in [L] may have is preferably a halogen atom, a haloalkyl group having 1 to 3 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 preferably 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-), and still more preferably a fluorine atom, an iodine atom, trifluoromethyl group, methyl group, hydroxy group or methoxy group. L 1 is R 3When not forming an alkyl group or an alicyclic hydrocarbon group, it is preferably a linear hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (wherein -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-), 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- or -CO-), or a group formed by combining a linear 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 (wherein -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-). More preferably, it is a linear hydrocarbon group having 1 to 8 carbon atoms which may have a substituent, an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent, or a group formed by combining a linear 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 (however, -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-). Even more preferably, it is a linear hydrocarbon group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 6 to 12 carbon atoms, a group formed by combining a linear hydrocarbon group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 6 to 12 carbon atoms, or a group formed by combining an alicyclic hydrocarbon group having 6 to 12 carbon atoms, a linear hydrocarbon group having 1 to 6 carbon atoms, and an alicyclic hydrocarbon group having 6 to 12 carbon atoms.

[0137] R 2Examples of the C1-C8 fluoroalkyl group in [context not provided] 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 number of carbon atoms 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 [context not provided], the C1-C6 fluoroalkyl group, as long as the upper limit of the number of carbon atoms permits, includes the C1-C6 fluoroalkyl groups listed in the examples of the fluoroalkyl group of R 2 similarly. R 2 is preferably a C1-C6 fluoroalkyl group, more preferably a C1-C3 fluoroalkyl group, still more preferably a trifluoromethyl group, a perfluoroethyl group or a perfluoropropyl group, and even more preferably a trifluoromethyl group when R 3 is a C1-C6 fluoroalkyl group. R2 When R 3 is a hydrogen atom, it is 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 L 2 include groups represented by the following formulas. Among the following formulas, * and ** represent bonding sites, and the two ** represent that one represents the bonding site with a hydroxy group and the other represents the bonding site with R 1A is L 1 is a part of the hydrocarbon group of L 1 and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. TIFF2025097300000107.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.

[0138] Examples of the structural unit (a4-A) include the following structural units. 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). TIFF2025097300000108.tif192167

[0139] When the resin (A) etc. 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% with respect to all the structural units of the resin (A) etc.

[0140] <Structural unit (a5)> Examples of the non-detachable hydrocarbon group contained 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 the formula (a5-1). TIFF2025097300000109.tif3971[In the 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 aliphatic hydrocarbon groups 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-.]

[0141] 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. 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 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.

[0142] 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. TIFF2025097300000110.tif18165[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.] 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 x8is 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.

[0143] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF2025097300000111.tif36147 Examples of the group represented by the formula (L1-2) include the following divalent groups. TIFF2025097300000112.tif23130 Examples of the group represented by the formula (L1-3) include the following divalent groups. TIFF2025097300000113.tif16147 Examples of the group represented by the formula (L1-4) include the following divalent groups. TIFF2025097300000114.tif13168L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0144] Examples of the structural unit (a5-1) include the following structural units and structural units in which the methyl group corresponding to R in the structural unit (a5-1) below is replaced by a hydrogen atom. 51 are mentioned. TIFF2025097300000115.tif104151 When the resin (A) contains 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).

[0145] 〈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-.

[0146] 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 further contain a heteroatom in addition to -SO2-O- as an atomic group constituting the ring, like the ring represented by formula (T 1 -2). Examples of the heteroatom include an oxygen atom, a sulfur atom or a nitrogen atom, and preferably an oxygen atom. TIFF2025097300000116.tif3077

[0147] 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, etc.

[0148] 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 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, and preferably a trifluoromethyl group. 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, and more preferably a methoxycarbonyl group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. From the viewpoint of easy production of the monomer leading to the structural unit (a6), a sultone ring having no substituent is preferred.

[0149] As the sultone ring, a ring represented by the following formula (T1’) is preferable. TIFF2025097300000117.tif2666[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 of R include the same as the substituents 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.

[0150] Examples of the ring represented by the formula (T1’) include the following rings. The bonding site is at an arbitrary position. Among them, those having the bonding site at the 1-position or the 3-position are preferable. TIFF2025097300000118.tif44147

[0151] 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 that leads to the structural unit (a6) is preferably a monomer having an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer.

[0152] The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2025097300000119.tif4077[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 group 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.]

[0153] 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, and a triiodomethyl group. 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. 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 those obtained by combining 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.

[0154] Examples of the structural unit (a6-0) include the following structural units. TIFF2025097300000120.tif93150

[0155] 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).

[0156] <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 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 is preferred.

[0157] 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). TIFF2025097300000121.tif26124[In formula (a7-A), R a7represents 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. 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. * 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-, where *** represents the bonding site with L a71 . na7 represents any integer from 0 to 2. When na7 is 2, the groups in the plurality of parentheses may be the same or different from each other. RA - represents a sulfonate anion or a carboxylate anion. ZA + represents an organic cation.

[0158] R a7 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R are the same as those exemplified by R of formula (a1-0). a01 And the like can be mentioned. Ra7 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 even more preferably a hydrogen atom or a methyl group.

[0159] X a71 When it is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025097300000122.tif3251[In the formula (X10), Ax represents a bonding species that bonds 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 represents a bonding species that bonds to L a71 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. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents any integer from 0 to 4, and when mx is an integer of 2 or more, a plurality of Rx may be the same as or different from each other.] When either Ax or Ay is a single bond, the other is preferably one or more selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate ester 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 the substituent include a single bond and a substituent represented by the following formula (X 10 -1)~Formula(X 10 -10) is a group represented by * -R a7 represents the bonding site with the carbon atom to which L is bonded. a71 It represents the binding site with X 20 is -O- or -NR a71 - represents. TIFF2025097300000123.tif43162 expression (X 10 -1)~Formula(X 10 Specific examples of the group represented by -10) include the following groups. TIFF2025097300000124.tif87163 Among them, X 10 is a single bond or a group of the formula (X 10 -1') and formula (X 10 -3')~expression(X 10 -10'), a single bond or a group represented by the formula (X 10 -1'), expression (X 10 -4'), expression (X 10 -5'), expression (X 10 -6') and formula (X 10 -10'), and more preferably a single bond, a group represented by the formula (X 10 -1'), a group represented by the formula (X 10 -5') or a group represented by the formula (X 10 -6') is more preferable.

[0160] L a71 The hydrocarbon group is a group formed 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, to form X. a71 and X a72 Also, L a72 The hydrocarbon group is a group formed 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, to form X. a72 and R.A. - Examples of such groups include groups that bond to the L a71 and L a72 Examples of the chain hydrocarbon group of L 0 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, the same groups as those described for the chain hydrocarbon group of X The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 20, and even more preferably 1 to 10. L a71 and L a72 Examples of the alicyclic hydrocarbon group of 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, etc. a71 and L a72 Examples of the polycyclic cycloalkyl group of 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 norbornyl group, an adamantyl group, etc. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group, a steroid group (steroid skeleton), etc. Also, examples of the ring in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one or more cycloalkyl groups 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. Also, a double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group represented by the following formula can be mentioned. When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 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 7 to 12. L a71 and L a72 Examples of the aromatic hydrocarbon group of and L include an aryl group from which one hydrogen atom has been removed. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorene group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, more preferably 5 to 10. L a71 and L a72 When -CH2- contained in the hydrocarbon group of and L 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 a71 and L a72 Among the hydrocarbon groups of and L, 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 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 alkanediylcarbonyl group, an alkanediylcarbonyloxy group, etc. 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. L a71 and L a72 Among the hydrocarbon groups of and L, 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 those exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. L a71 and L a72Among the hydrocarbon groups, -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 and a thiophene ring, respectively. L a71 and L a72 Examples of the group formed by combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group of L and L include the group formed by combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, the group formed by combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, the group formed by combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and the group formed by combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group, and the above aromatic hydrocarbon group. The above combined groups are included. The group formed by combining the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be a condensed ring. L a71 and L a72 Examples of the substituent that the hydrocarbon group of L and L 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, etc. L a71 and L a72 When the group of L and L is 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 L and L is replaced by -O-, -CO-, -S-, or -SO2-, the hydrocarbon group of L b1‘ and L b2‘ 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, a sulfonyl group, etc. na7 is preferably 0 or 1. ZA in formula (a7-A) + is the same as the cation Z1 in the salt represented by formula (B1) described later + and the like can be mentioned.

[0161] Examples of the structural unit represented by the formula (a7-A) include the following structural units, R a7 wherein the group corresponding to the methyl group of is replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms that may have a halogen atom (for example, a trifluoromethyl group), and the structural unit described in International Publication No. 2012 / 050015. ZA + represents an organic cation. TIFF2025097300000126.tif131156

[0162] TIFF2025097300000127.tif244163

[0163] 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). TIFF2025097300000128.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 that 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 that may have a substituent. R II2 and R II3 each independently represent a hydrocarbon group having 1 to 18 carbon atoms that 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 that may have a halogen atom of are the same as the halogen atom and the alkyl group that may have a halogen atom in the formula (a7-A). R II1Examples 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 II3 Examples 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. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group formed by combining these are the same as those described above. A II1 Examples of the divalent linking group represented by include, for example, 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, and combinations thereof may also be possible. 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; and 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 the following. 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 formula, * and ** represent bonding sites, and * represents the bonding site with R II2 and represents the bonding site with R TIFF2025097300000129.tif123162[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]

[0164] Examples of the structural unit containing the cation in formula (a7-B) include the structural unit represented by the following and the group corresponding to the methyl group of R a7 in which the methyl group is replaced by 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 the like JPEG2025097300000130.jpg72163

[0165] A - Examples of the organic anion represented by include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, and the like. A -The organic anion represented by [[ID=]] is preferably a sulfonate anion, and more preferably an anion contained in the salt represented by the following formula (B1) as the sulfonate anion. Examples of the sulfonylimide anion, sulfonylmethide anion, and carboxylate anion are the same as those exemplified as the anion of the acid generator (B).

[0166] Examples of the structural unit represented by the formula (a7-B) include structural units represented as follows. JPEG2025097300000131.jpg96157

[0167] When the resin (A) contains the structural unit (a7), the structural unit (a7) may be contained alone or in two or more kinds. The content 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).

[0168] The resin (A) may contain structural units other than the above-mentioned structural units, and examples of such structural units include structural units well-known in the art. The resin (A) is preferably a resin composed of the structural unit (a1) and the structural unit (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 the structural unit (a1-1) and / or 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 a structural unit represented by the formula (a2-A) or a structural unit represented by the formula (a2-1). 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).

[0169] 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 the monomers leading 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). In this specification, the weight average molecular weight is a value determined by gel permeation chromatography under the conditions described in the examples.

[0170] <Resin other than resin (A)> The resist composition of the present invention may be used in combination with a resin other than the resin (A). Examples of the resin other than the resin (A) include resins containing the structural unit (a2), the structural unit (a4), or the structural unit (a5) (hereinafter sometimes referred to as resin (X)). Among them, examples of the resin (X) include a resin composed only of the structural unit (a2), a resin composed only of the structural unit (a4), and a resin composed of the structural unit (a4) and the structural unit (a5). Examples of the structural unit that the resin (X) may further have include the structural unit (a3) and structural units derived from other known monomers. When the resin (X) contains the structural unit (a2), the structural unit (a2) is preferably the structural unit (a2-A) or the structural unit (a2-B). 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, still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Further, 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, still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Further, 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, still more preferably 80 mol% or more, based on the total of all the structural units of the resin (X). Further, it is 100 mol% or less. Specifically, it is 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, still more preferably 80 to 100 mol%. Among them, the resin (X) is preferably a resin composed of only the structural unit (a4) and / or the structural unit (a5). In this case, the ratio of the structural unit (a4): the structural unit (a5) is 0:100 to 100:0, preferably 10:90 to 90:10, more preferably 30:70 to 70:30 or 40:60 to 60:40. 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 the 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 (A).

[0171] 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 particularly preferably 1 to 8 parts by mass with respect to 100 parts by mass of the resin (A).

[0172] 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, based on the solid content of the resist composition. When containing resins other than the resin (A), the total content of the resin (A) and the resins other than the resin (A) 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, based on the solid content of the resist composition. The solid content of the resist composition and the content of the resin with respect thereto can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0173] <Solvent (E)> The content of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less, preferably 92% by mass or more and 99% by mass or less, more preferably 94% by mass or more and 99% by mass or less. The content 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.

[0174] <Quencher (C)> Examples of the quencher (C) include basic nitrogen-containing organic compounds and salts that generate an acid having a lower acidity than the acid generated from the acid generator (B). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15% by mass, more preferably about 0.01 to 10% by mass, further 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. Examples of the basic nitrogen-containing organic compounds include amines and ammonium salts. Examples of the amines include aliphatic amines and aromatic amines. Examples of the 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, etc. 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, choline, and the like.

[0175] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is indicated by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is a salt having an acid dissociation constant of the acid generated from the salt usually of -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 (B) 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. The salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is preferably a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (B) (a salt having a carboxylic acid anion), more preferably a weak acid inner salt (D), and even more preferably a diphenyliodonium salt containing a phenyl group substituted with a carboxylic acid anion among the weak acid inner salts (D). TIFF2025097300000132.tif97153

[0176] 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. Specifically, salts represented by the following formulae can be mentioned.

[0177] TIFF2025097300000133.tif1695[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 any one 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 and the like. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and may be either saturated or unsaturated. Examples include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclononyl group, cyclododecyl group, norbornyl group, adamantyl group and the like. 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, 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 a group in which an oxy group (-O-) is bonded to the above acyl group, etc. Examples of the alkoxycarbonyl group include a 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.

[0178] More specifically, the following salts can be mentioned. TIFF2025097300000134.tif72165

[0179] <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 are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used.

[0180] <Preparation of resist composition> The resist composition of the present invention can be prepared by mixing the compound (I), the acid generator (B), and, if necessary, the resin (A), a resin other than the resin (A), the solvent (E), the quencher (C), and the other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during 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. In addition, the mixing means is 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.

[0181] <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 composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and It includes a step of developing the composition layer after heating. To apply the resist composition onto a substrate, it can usually be done by using a commonly used device such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers and organic substrates with a resist film or the like formed on the surface. Before applying the resist composition, the substrate may be cleaned, and 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 a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), an F2 excimer laser (wavelength 157 nm), those that convert laser light from a solid laser light source (such as a YAG or semiconductor laser) into harmonic laser light in the far ultraviolet region or vacuum ultraviolet region and emit it, those that irradiate electron beams, extreme ultraviolet light (EUV), etc. can be used. In this specification, irradiating these radiations may sometimes be collectively referred to as "exposure". 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 subjected to a heat treatment (so-called post-exposure bake) to promote the deprotection reaction in the acid-labile group. The heating temperature is usually about 50 to 200 °C, preferably about 70 to 150 °C. A 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 applying, drying, exposing, and heating the resist composition may be repeated on the composition layer after exposure. The heated composition layer is usually developed using a developer with a developing apparatus. Examples of the developing method include a dip method, a paddle method, a spray method, a 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 developer 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 alkali developer is used as the developer. The alkali developer may be any of various alkaline aqueous solutions used in this field. For example, an aqueous solution of tetramethylammonium hydroxide or (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline), etc. may be mentioned. The alkali 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 developer containing an organic solvent (hereinafter sometimes referred to as an "organic-based developer") is used as the developer. Examples of the organic solvent contained in the organic-based developer 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-based 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 even more preferably substantially only the organic solvent. Among them, as the organic-based developer, a developer containing butyl acetate and / or 2-heptanone is preferable. In the organic-based 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 even 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 replacing with a solvent of a type different from the organic developer. It is preferable to wash the resist pattern after development with a rinsing solution. The rinsing 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 rinsing solution remaining on the substrate and the pattern.

[0182] <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, and is particularly useful for semiconductor microfabrication.

Examples

[0183] 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 under the following conditions. Apparatus: HLC-8120GPC type (manufactured by Tosoh Corporation) Column: TSKgel Multipore H XL -M x 3 + guardcolumn (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)

[0184] In addition, the structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC: Agilent 1100 type, MASS: Agilent LC / MSD type). In the following examples, the value of this molecular ion peak is indicated as "MASS".

[0185] Synthesis Example 1: Synthesis of the compound represented by formula (I-1) 2.76 parts of the compound represented by formula (I-1-a), 0.92 parts of the compound represented by formula (I-1-b), and 30 parts of methanol were charged and stirred at 23°C for 30 minutes. Then, 0.90 parts of pyridine was added and stirred at 23°C for 1 hour. To the resulting reaction product, 100 parts of chloroform was added and stirred, then 30 parts of 5% oxalic acid aqueous solution was added and stirred at 23°C for 30 minutes. Then, it was allowed to stand and separated. 30 parts of ion-exchanged water was charged into the recovered organic layer, stirred at 23°C for 30 minutes, and the organic layer was recovered by liquid separation. This washing operation with water was performed 5 times. By concentrating the obtained organic layer, 2.54 parts of the compound represented by formula (I-1) was obtained. MASS: 306.0 [M+H] +

[0186] Synthesis Example 2: Synthesis of the compound represented by formula (I-2) 2.76 parts of the compound represented by formula (I-1-a), 0.76 parts of the compound represented by formula (I-2-b), and 30 parts of methanol were charged and stirred at 23°C for 30 minutes. Then, magnesium sulfate was added, and the mixture was refluxed and dehydrated at 65°C for 6 hours and then cooled to 23°C. To the resulting reaction product, 100 parts of chloroform was added and stirred, then 30 parts of 5% oxalic acid aqueous solution was added and stirred at 23°C for 30 minutes. Then, it was allowed to stand and separated. 30 parts of ion-exchanged water was charged into the recovered organic layer, stirred at 23°C for 30 minutes, and the organic layer was recovered by liquid separation. This washing operation with water was performed 5 times. By concentrating the obtained organic layer, 1.98 parts of the compound represented by formula (I-2) was obtained. MASS: 292.0 [M+H] +

[0187] Synthesis Example 3: Synthesis of the compound represented by formula (I-12) 3.96 parts of the compound represented by formula (I-12-a), 0.92 parts of the compound represented by formula (I-1-b), and 30 parts of methanol were charged and stirred at 23°C for 30 minutes. Then, 0.90 parts of pyridine was added and stirred at 23°C for 1 hour. To the resulting reaction mixture, 100 parts of chloroform was added and stirred, then 30 parts of 5% aqueous oxalic acid solution was added and stirred at 23°C for 30 minutes. Then, it was allowed to stand and separated. 30 parts of ion-exchanged water was charged into the recovered organic layer, stirred at 23°C for 30 minutes, and the organic layer was recovered by liquid separation. This washing operation with water was carried out 5 times. By concentrating the obtained organic layer, 3.29 parts of the compound represented by formula (I-12) was obtained. MASS: 426.1 [M+H] +

[0188] Synthesis Example 4: Synthesis of the compound represented by formula (I-5) 2.24 parts of the compound represented by formula (I-5-a), 0.92 parts of the compound represented by formula (I-1-b), and 30 parts of methanol were charged and stirred at 23°C for 30 minutes. Then, 0.90 parts of pyridine was added and stirred at 23°C for 1 hour. To the resulting reaction mixture, 100 parts of chloroform was added and stirred, then 30 parts of 5% aqueous oxalic acid solution was added and stirred at 23°C for 30 minutes. Then, it was allowed to stand and separated. 30 parts of ion-exchanged water was charged into the recovered organic layer, stirred at 23°C for 30 minutes, and the organic layer was recovered by liquid separation. This washing operation with water was carried out 5 times. By concentrating the obtained organic layer, 2.18 parts of the compound represented by formula (I-5) was obtained. MASS: 254.0 [M+H] +

[0189] Synthesis Example 5: Synthesis of the compound represented by formula (I-15) 3.60 parts of the compound represented by TIFF2025097300000139 (I-15-a), 0.92 parts of the compound represented by formula (I-1-b), and 30 parts of methanol were charged and stirred at 23 °C for 30 minutes. Then, 0.90 parts of pyridine was added and stirred at 23 °C for 1 hour. To the resulting reaction product, 100 parts of chloroform was added and stirred, then 30 parts of 5% aqueous oxalic acid solution was added and stirred at 23 °C for 30 minutes. Then, it was allowed to stand and separated. 30 parts of ion-exchanged water was charged into the recovered organic layer, stirred at 23 °C for 30 minutes, and the organic layer was recovered by liquid separation. This washing operation with water was performed 5 times. By concentrating the obtained organic layer, 3.33 parts of the compound represented by formula (I-15) was obtained. MASS: 390.1 [M+H] +

[0190] 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 (a1-2-6)" etc. according to their formula numbers. TIFF2025097300000140.tif4151

[0191] Synthesis Example 6 [Synthesis of Resin A1] As monomers, monomer (a1-4-2) and monomer (a1-2-6) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6)] was 38:62. 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, azobisisobutyronitrile was added as an initiator so that it was 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Then, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, stirred for 6 hours, and then separated. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. Thus, resin A1 (copolymer) having a weight average molecular weight of about 5.4×10 3 was obtained in a yield of 89%. This resin A1 has the following structural units. TIFF2025097300000141.tif2887

[0192] <Preparation of Resist Composition> As shown in Table 1, each of the following components was 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

[0193] <Resin> A1: Resin A1 <Acid Generator (B)> B1-43: Salt represented by formula (B1-43) (synthesized according to the examples of JP-A-2016-47815) TIFF2025097300000143.tif43114<Compound (I), etc.> I-1: Compound represented by formula (I-1) I-2: Compound represented by formula (I-2) I-5: Compound represented by formula (I-5) I-12: Compound represented by formula (I-12) I-15: Compound represented by formula (I-15) <Quencher (C)> IX-1: Obtained from Tokyo Chemical Industry JPEG2025097300000144.jpg1351<Solvent> Propylene Glycol Monomethyl Ether Acetate 400 parts Propylene Glycol Monomethyl Ether 100 parts γ-Butyrolactone 5 parts

[0194] (Electron Beam Exposure Evaluation of Resist Composition: Alkaline Development) A 6-inch silicon wafer was treated with hexamethyldisilazane at 90 °C for 60 seconds on a direct hot plate. 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 pre-baked for 60 seconds at the temperature shown in the "PB" column of Table 1 on a direct hot plate to form a composition layer. Using an electron beam lithography machine ("ELS-F125 125 keV" manufactured by Elionix, Inc.), the exposure dose was changed stepwise on the composition layer formed on the wafer, and direct drawing was performed so as to obtain a line and space pattern (pitch 60 nm / line width 30 nm) after development. After exposure, post-exposure baking was performed for 60 seconds at the temperature shown in the "PEB" column of Table 1 on a hot plate. Next, the composition layer on this silicon wafer was paddle-developed for 60 seconds at 23 °C using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide as a developer to obtain a resist pattern. The obtained resist pattern (line and space pattern) was observed with a scanning electron microscope, and the exposure dose at which the line width and space width of the line and space pattern with a pitch of 60 nm became 1:1 was defined as the effective sensitivity. Line edge roughness evaluation (LER): The line edge roughness was determined by measuring the amplitude of the unevenness of the side wall surface of the resist pattern manufactured with the effective sensitivity using a scanning electron microscope. The results are shown in Table 2.

Table 2

Industrial Applicability

[0195] The resist composition of the present invention is excellent in the line edge roughness (LER) of the obtained resist pattern, and thus is suitable for semiconductor microfabrication and is extremely useful industrially.

Claims

1. A resist composition comprising a compound represented by formula (I) and an acid generator. [In formula (I), R 1 represents a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -CO-, -NR ２ -or-SO ２ It may be replaced with -. R ２ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. Ring W represents an alicyclic hydrocarbon ring having 3 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. X ０ represents a halogen atom or a hydrocarbon group having 1 to 72 carbon atoms and a halogen atom, and the —CH 2 - is -O-, -S-, -CO- or -SO ２ The hydrocarbon group may be substituted with -, and may have a substituent other than a halogen atom. nc1 represents an integer of 1 to 6. When nc1 is 2 or more, the groups in the parentheses may be the same or different.]

2. X ０ a group formed by combining two or more selected from the group consisting of an iodine atom, a fluorinated alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, and an aromatic hydrocarbon group having 6 to 36 carbon atoms (the alicyclic hydrocarbon group and the chain hydrocarbon group may have a fluorine atom, a fluorinated alkyl group having 1 to 4 carbon atoms, or a hydroxy group, the aromatic hydrocarbon group may have a fluorine atom, an iodine atom, a fluorinated alkyl group having 1 to 4 carbon atoms, or a hydroxy group, and the -CH contained in the alicyclic hydrocarbon group and the chain hydrocarbon group ２ 2. The resist composition according to claim 1, wherein - may be replaced by -O- or -CO-.

3. 2. The resist composition according to claim 1, wherein the acid generator comprises a salt represented by formula (B1). [In formula (B1), L b1 represents a single bond or a (nb1+1)-valent hydrocarbon group which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced with -. L b2 represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced by -. 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 - is -O-, -S-, -SO 2 It may be replaced by --or --CO--. nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the parentheses may be the same or different. Z1 ＋ represents an organic cation.

4. The method further comprises the steps of: The resist composition according to claim 1, which comprises a structural unit represented by formula (a2-A): [In 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 the —CH ２ - is -O-, -CO- or -NR ａ２８ May be replaced with -. 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 an integer of 1 to 5, and when nA2 is 2 or more, the groups in the multiple parentheses may be the same or different. na21 represents an integer of 0 to 4, and when na21 is 2 or more, a plurality of R ａ２７ may be the same or different from each other. mc represents an integer of 0 to 2.

5. Further comprising a structural unit having an acid labile group, The resist composition according to claim 1, wherein the structural unit having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L ａ１ and L ａ２ are each independently -O- or *-O-(CH ２ ) ｋ１ represents --CO--O--, k1 represents an integer of 1 to 7, and * represents the bonding site with --CO--. R a01 , R ａ４ and R ａ５ each 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 combination thereof, and the alkyl group, alicyclic hydrocarbon group and 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, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom. m1′ represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. [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 the —CH ２ - is -O-, -CO- or -NR ａ１８ May be replaced with -. 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; 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 the hydrocarbon group and the -CH 2 - may be replaced by -O- or -S-. na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the parentheses may be the same or different. na11 represents an integer of 0 to 4, and when na11 is 2 or more, a plurality of R ａ１７ may be the same or different from each other. mc represents an integer of 0 to 2. [In 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 is a single bond or *-(CH 2 ) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents --O-- or --S--. s1 represents an integer of 1 to 3. s1′ represents an integer of 0 to 3.] [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, together with the carbon atoms to which they are attached, a ring having 3 to 20 carbon atoms. X a61 is a single bond, -CO-O-* or -CO-NR a65 - represents *, * represents a bonding site with Ar, R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 is a single bond, *-O-L a61 - or *-CO-OL a62 -, * represents a bonding site with Ar, 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.

6. (1) A step of applying the resist composition according to claim 1 onto a substrate; (2) A step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising the steps of:

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