Resist composition and method for producing resist pattern

Abstract

To provide a resist composition and the like which allow a resist pattern having good CD uniformity (CDU) to be produced.SOLUTION: The resist composition contains: a resin containing a structural unit derived from a compound represented by formula (I); and an acid generator containing a salt represented by formula (B1). [In the formula (I), R1-R5 each represent a hydrogen atom, a halogen atom or the like; X11 and X12 each represent -SO2-, -O-SO2-, -SO2-O- or the like; and X21 and X22 each represent a single bond, -O- or the like.]SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002] Patent Document 1 describes a resist composition containing a resin containing a structural unit derived from a compound having the following structural formula and an acid generator containing a salt having the following structural formula. TIFF2025097301000001.tif27103

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 CD uniformity (CDU) than a resist pattern formed from a resist composition containing a resin containing a structural unit derived from the above compound.

Means for Solving the Problems

[0005] The present invention includes the following inventions. 〔1〕A resist composition containing a resin containing a structural unit derived from a compound represented by formula (I) and an acid generator containing a salt represented by formula (B1). TIFF2025097301000002.tif30130[In formula (I), R 1 、R 2 and R 3Each independently represents a halogen atom, a haloalkyl group having 1 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkyl group may be replaced by -O- or -CO-. R 4 and R 5 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 11 and X 12 Each independently represents -SO2-, -O-SO2-, or -SO2-O-. X 21 and X 22 Each independently represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR 7 -**, *-NR 7 -CO-O-**, *-O-CO-NR 7 -** or *-Ax-Ph-Ay-**. R 7 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 4 or R 5 is bonded. n12 represents any integer from 0 to 4, and when n12 is 2 or more, the plurality of parentheses may be the same or different from each other. m1 represents any integer from 0 to 4, and when m1 is 2 or more, the plurality of R 1 may be the same or different from each other. m2 represents any integer from 0 to 4, and when m2 is 2 or more, the plurality of R 2 may be the same or different from each other. m3 represents any integer from 0 to 4, and when m3 is 2 or more, the plurality of R 3They may be the same as or different from each other. TIFF2025097301000003.tif1395[In formula (B1), L b1 represents a (nb1 + 1)-valent hydrocarbon group which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. L b2 represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 represents a 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 the plurality of parentheses may be the same as or different from each other. Z1 + represents an organic cation. [2] X 21 and X 22 are each independently a single bond or a group represented by any of formula (X 20 -1) to formula (X 20 -10), and the resist composition according to [1]. TIFF2025097301000004.tif43162[In formula (X 20 -1) to formula (X 20 -10), *, ** are bonding sites, and * represents the bonding site with the carbon atom to which R 4 or R 5 is bonded. Rx represents a halogen atom, a hydroxy group, a C1-6 fluoroalkyl group, a C1-18 alkyl group or a C1-6 alkoxy group. mx represents any integer from 0 to 4. X 20 represents -O- or -NR 7 -. R7 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. 〔3〕The resist composition according to 〔1〕or 〔2〕, wherein the resin containing a structural unit derived from the compound represented by the formula (I) further contains at least one selected from the group consisting of a structural unit represented by the formula (a1-0), a structural unit represented by the formula (a1-1), a structural unit represented by the formula (a1-2), a structural unit represented by the formula (a1-4), and a structural unit represented by the formula (a1-5). TIFF2025097301000005.tif44145[In the formula (a1-0), the formula (a1-1) and the formula (a1-2), L a01 、L a1 and L a2 each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents an integer of any one of 1 to 7, and * represents a 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. 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 an integer of any one of 0 to 3. TIFF2025097301000006.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 the -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 within 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.] TIFF2025097301000007.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 1 to 4, and * represents the bonding site with L 51 . L 51 , L 52 , L 53 and L 54 each independently represent -O- or -S-. s1 represents an integer of 1 to 3. s1’ represents an integer of 0 to 3.] 〔4〕The resist composition according to any one of 〔1〕~〔3〕, wherein the resin containing a structural unit derived from the compound represented by formula (I) further contains a structural unit represented by formula (a1-6). TIFF2025097301000008.tif3479[In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a62 , R a63 and R a64 each independently represent 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 a bond 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, and * represents a bond to -Ar, and L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. 〔5〕The resist composition according to any one of 〔1〕~〔4〕, wherein the resin containing a structural unit derived from the compound represented by the formula (I) further contains a structural unit represented by the formula (a2-A). TIFF2025097301000009.tif30128 [In the formula (a2-A), R a2 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO-, or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a2 represents a single bond or a carbonyl group. nA2 represents any integer from 1 to 5, and when nA2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na21 represents any integer from 0 to 4, and when na21 is 2 or more, the plurality of R a27 may be the same as or different from each other. mc represents any integer from 0 to 2. The resist composition according to any one of [1] to [5], wherein the resin containing a structural unit derived from the compound represented by the formula (I) further contains a structural unit represented by the formula (a2-D). TIFF2025097301000010.tif51106[In the formula (a2-D), R a2 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO-, or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R a21 and R a22 each independently represent a fluorinated alkyl group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents any integer from 1 to 5. When nD2 is 2 or more, the plurality of parentheses may be the same as or different from each other. nD22 represents any integer from 0 to 4. When nD22 is 2 or more, the plurality of R a27 may be the same as or different from each other.] The resist composition according to any one of [1] to [6], further containing a salt that generates an acid having a lower acidity than the acid generated from the acid generator. (1) Coating the resist composition according to any one of [1] to [7] on a substrate; (2) Drying the coated composition to form a composition layer; (3) Exposing the composition layer; (4) Heating the exposed composition layer, and (5) Developing the heated composition layer, a method for manufacturing a resist pattern including these steps. [Advantages of the Invention]

[0006] By using the resist composition of the present invention, a resist pattern can be manufactured with good CD uniformity (CDU). [Embodiments for Carrying Out the Invention]

[0007] In this specification, the term "(meth)acrylic monomer" means "at least one of acrylic monomers and methacrylic monomers". 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 it is replaced by -(X is any sign) or -SO2-, the same examples shall apply to each group, and the number of carbon atoms before replacement shall be taken as the number of carbon atoms of hydrocarbon groups and the like. "Combined group" means a group formed by bonding 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- group) 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 is eliminated to form a hydrophilic group (e.g., hydroxy group or carboxy group). A base-labile group means a group that, when contacted with a base (e.g., trimethylamine, tetramethylammonium hydroxide, etc.), the leaving group is eliminated to form a hydrophilic group (e.g., carboxy group or hydroxy group, etc.). 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, etc. 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 below from the total amount of the resist composition.

[0008] 〔Resist composition〕 The resist composition of the present invention contains a resin (hereinafter sometimes referred to as "resin (A)") containing a structural unit derived from a compound represented by formula (I) (hereinafter sometimes referred to as "compound (I)") and an acid generator (hereinafter sometimes referred to as "acid generator (B1)") containing a salt represented by formula (B1) (hereinafter sometimes referred to as "salt (B1)"). Resin (A) may be a polymer having only one kind of structural unit derived from compound (I), or a copolymer containing two or more kinds. Further, resin (A) may contain structural units other than the structural units derived from compound (I) described below. The resist composition of the present invention may contain one type of resin (A), or may contain two or more types of resins (A) each composed of partially or entirely different structural units. Also, it may contain one type of acid generator (B1), or may contain two or more types of acid generators (B1) different from each other. The resist composition of the present invention may further contain a resin other than the resin (A), 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)"), etc., or may contain a photopolymerization initiator (hereinafter sometimes referred to as "photopolymerization initiator (G)"). The resist composition of the present invention preferably contains a solvent (hereinafter sometimes referred to as "solvent (E)").

[0009] 〈Compound (I)〉 The resist composition of the present invention contains a resin (A) containing a structural unit derived from compound (I). TIFF2025097301000011.tif30130[In formula (I), all the symbols have the same meanings as described above respectively.]

[0010] R 1 、R 2 and R 3 Examples of the halogen atoms of R, R, and R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, etc. R 1 、R 2 and R 3The C1-C12 haloalkyl group refers to an alkyl group having 1 to 12 carbon atoms with a halogen atom, and examples include a fluoroalkyl group having 1 to 12 carbon atoms, a chloroalkyl group having 1 to 12 carbon atoms, a bromoalkyl group having 1 to 12 carbon atoms, an iodoalkyl group having 1 to 12 carbon atoms, and the like. Examples of the haloalkyl group include a perfluoroalkyl group having 1 to 12 carbon atoms (trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, perfluoropentyl group, perfluorohexyl group, etc.), fluoromethyl group, difluoromethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, 3,3,3-trifluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, chloromethyl group, bromomethyl group, iodomethyl group, and the like. The number of carbon atoms of the haloalkyl group is preferably 1 to 9, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. R 1 , R 2 and R 3 Examples of the C1-C12 alkyl group of R, R, and R include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, octyl group, nonyl 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.

[0011] R 1 , R 2 and R 3When -CH2- contained in the alkyl group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the alkyl group. Examples of the replaced groups 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-), 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-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-O-), and groups formed by combining two or more of these groups. Examples of the alkoxy group include alkoxy groups having 1 to 11 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group. 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 alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 11 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 11 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 10 carbon atoms, such as butoxycarbonyloxy group and the like. The number of carbon atoms of the alkoxycarbonyl group, the alkylcarbonyl group and the alkylcarbonyloxy group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3, respectively. The number of carbon atoms of the alkoxycarbonyloxy group is preferably 2 to 6, more preferably 2 to 4, and still more preferably 2 or 3 even if it is 2 to 8. R 1 , R 2 and R 3 are each independently preferably a fluorine atom, an iodine atom, a hydroxy group, a haloalkyl group having 1 to 6 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 hydroxy group, a fluoroalkyl group having 1 to 4 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-), still more preferably a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and even more preferably a fluorine atom, an iodine atom or a trifluoromethyl group.

[0012] R 4 and R 5 Examples of the halogen atom of R and R include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. Examples of the alkyl group 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 in the alkyl group is preferably 1 to 4, more preferably 1 or 2, and even more preferably 1. Examples of the alkyl group which may have a halogen atom include alkyl fluoride groups having 1 to 6 carbon atoms, alkyl chloride groups having 1 to 6 carbon atoms, alkyl bromide groups having 1 to 6 carbon atoms, alkyl iodide groups having 1 to 6 carbon atoms, and the like. Examples of the haloalkyl group include perfluoroalkyl groups having 1 to 6 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, 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, fluoromethyl group, difluoromethyl group, trifluoromethyl group, perfluorobutyl, and the like. The number of carbon atoms in the haloalkyl group is preferably 1 to 4, and more preferably 1 to 3. R 4 and R 5 are 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, even more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0013] X 21 and X 22 in the case of the group represented by *-Ax-Ph-Ay-**, is preferably a linking group represented by the following formula (X20). TIFF2025097301000012.tif3449[In the formula (X20), Ax represents a bonding species that binds to the carbon atom to which R 4 or R 5 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, an amide bond, and a carbonate ester bond. Ay is R 1 or R3 represents a bonding species that binds to a benzene ring capable of bonding, 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, an amide bond, and a carbonate bond. Rx represents a halogen atom, a hydroxy group, a C1-C6 fluoroalkyl group, a C1-C18 alkyl group, or a C1-C6 alkoxy group. mx represents any integer from 0 to 4, and when mx is an integer of 2 or more, a plurality of Rx may be the same 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, an amide bond, and a carbonate bond. When either Ax or Ay is an amide bond, it is preferably a bond represented by -CO-NR 7 -. 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. The bonding position of Ay in the phenylene group is preferably the m-position or the p-position with respect to Ax, and more preferably the p-position. X 21 and X 22 include, for example, groups represented by any of the following formulas (X 20 -1) to formula (X 20 -10). * represents the bonding position to the carbon atom to which -R 4 or R 5 is bonded. ** represents the bonding position to the benzene ring to which R 1 or R 3 can be bonded. TIFF2025097301000013.tif43162 [In formulas (X 20 -1) to formula (X 20 -10), *, ** are bonding sites, and * represents the bonding site to the carbon atom to which R 4 or R 5 is bonded. Rx represents a halogen atom, a hydroxy group, a C1-C6 fluoroalkyl group, a C1-C18 alkyl group or a C1-C6 alkoxy group. mx represents any integer from 0 to 4. X 20 represents -O- or -NR 7 -. R 7 represents a hydrogen atom or a C1-C6 alkyl group. R 7 The alkyl group of R 4 or R 5 includes the same ones as those exemplified by R R 7 is preferably a hydrogen atom or a C1-C4 alkyl group, more preferably a hydrogen atom or a C1-C3 alkyl group, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. Specific examples of the group represented by formula (X 20 -1) to formula (X 20 -10) include the following groups. TIFF2025097301000014.tif87163 Among them, X 20 is preferably a single bond or a group represented by formula (X 20 -1’) and formula (X 20 -3’) to formula (X 20 -10’), more preferably a single bond or a group represented by formula (X 20 -1’), formula (X 20 -4’), formula (X 20 -5’), formula (X 20 -6’) and formula (X 20 -10’), and still more preferably a single bond, a group represented by formula (X 20 -1’), a group represented by formula (X 20 -5’) or a group represented by formula (X 20 -6’). m1 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 or 1. m2 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 or 1. m3 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 or 1. n12 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 or 1. When n12 is 0, the bonding position of X 11 is preferably bonded to the p-position of the benzene ring with respect to the bonding positions of X 21 and X 22 . When n12 is from 1 to 4, the bonding position of X 11 is preferably bonded to the p-position of the benzene ring with respect to the bonding position of X 21 , and the bonding position of X 12 is preferably bonded to the p-position of the benzene ring with respect to the bonding position of X 22 . For the bonding positions with respect to adjacent X 12 and X 11 , it is preferably bonded to the p-position or m-position of the benzene ring.

[0014] Compound (I) includes compounds represented by the following formula. In the following compounds, structural units in which the hydrogen atoms corresponding to R 4 or R 5 of compound (I) are replaced by methyl groups can also be cited as specific examples of compound (I). TIFF2025097301000015.tif203162

[0015] TIFF2025097301000016.tif194164

[0016] <Structural unit derived from compound (I)> The structural unit derived from compound (I) is a structural unit represented by formula (IP) (hereinafter sometimes referred to as "structural unit (IP)"). The structural unit (IP) is CH2=C-R contained in compound (I) 4 and / or CH2=C-R 5 shows the state where the double bond is cleaved. The structural unit (IP) may be in a state where either CH2=C-R 4 or CH2=C-R 5 is not cleaved. TIFF2025097301000017.tif36149[In the formula, all symbols have the same meanings as described above.]

[0017] <Resin containing the structural unit (IP) derived from compound (I)> The resin of the present invention is a resin containing the structural unit (IP) (hereinafter sometimes referred to as "resin (A)"). Resin (A) may be a homopolymer containing one kind of structural unit (IP) or a copolymer containing two or more kinds of structural units (IP). Further, resin (A) may contain a structural unit other than the structural unit (IP). Examples of the structural unit other than the structural unit (IP) include a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)") and a structural unit other than the structural unit having an acid-labile group. Examples of the structural unit other than the structural unit having an acid-labile group include a structural unit having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)") and structural units known in the art. The content of the structural unit (IP) is usually 0.1 to 100 mol%, preferably 0.1 to 50 mol%, more preferably 0.1 to 30 mol%, and still more preferably 0.1 to 10 mol% based on the total amount of resin (A).

[0018] 〈Structural unit (a1)〉 The structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid-labile group contained in the resin (A) or the like is preferably a group represented by the formula (1) (hereinafter also referred to as group (1)) and / or a group represented by the formula (2) (hereinafter also referred to as group (2)). TIFF2025097301000018.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.] TIFF2025097301000019.tif2278[In formula (2), R a1’ and R a2’ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, 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, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.]

[0019] R a1 、R a2 and R a3Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. R a1 , R a2 and R a3 Examples of the alkenyl group in include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site). R a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms. TIFF2025097301000020.tif10159R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group in include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, and the like. Preferably, ma is 0 and na is 1. R a1 and R a2 When they 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-. TIFF2025097301000021.tif28139

[0020] R a1’ R a2’ and R a3’ Examples of the hydrocarbon group in R include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. a1 R a2 R a3 The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and the group formed by combining these are the same as those exemplified for R R a2’ and R a3’ 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-Ra3’ Examples include the following groups. * represents a bond. TIFF2025097301000022.tif19124R a1 , R a2 , R a3 , R a1 , R a2’ and R a3’ Examples of the halogen atom that may be included in R include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R a1’ and R a2’ It is preferable that at least one of them is a hydrogen atom. na’ is preferably 0.

[0021] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 are alkyl groups, ma = 0, and na = 1. A tert-butoxycarbonyl group is preferable as such a group. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, and R a3 is an alkyl group, ma = 0, and na = 1. In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1. Specific examples of the group (1) include the following groups. * represents a bond. TIFF2025097301000023.tif150162

[0022] Specific examples of the group (2) include the following groups. * represents a bond. TIFF2025097301000024.tif55153

[0023] The monomer (a1) is preferably a monomer having an acid-labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid-labile group. Among the (meth)acrylic monomers having an acid-labile group, those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms are preferably mentioned. If a resin (A) or the like having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0024] Examples of the structural unit derived from the (meth)acrylic monomer having the group (1) include a structural unit represented by the formula (a1-0) (hereinafter sometimes referred to as the structural unit (a1-0)), a structural unit represented by the formula (a1-1) (hereinafter sometimes referred to as the structural unit (a1-1)), or a structural unit represented by the formula (a1-2) (hereinafter sometimes referred to as the structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2), more preferably at least one or two structural units selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2025097301000025.tif43144[In the formula (a1-0), the formula (a1-1), and the formula (a1-2), all the symbols represent the same meaning as described above.]

[0025] 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 in the above formula include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group. R a01 , R a4 and R a5 is preferably a hydrogen atom or a methyl group, and more preferably a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or *-O-(CH2) k01 It is -CO-O- (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 and R a04 The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group and combinations thereof in the formula (1) are R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a6 and R a7 The alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combinations thereof in the formula (1) include R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a02 , Ra03 and R a04 The alkyl group in a04 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 a6 and 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 alicyclic hydrocarbon group of a7 preferably has 5 to 12 carbon atoms, more preferably 5 to 10 carbon atoms. R a02 R a03 R a04 R a6 and R a7 The aromatic hydrocarbon group of a7 preferably has 6 to 12 carbon atoms, more preferably 6 to 10 carbon atoms. The group formed by combining an alkyl group and an alicyclic hydrocarbon group preferably has a total carbon number of 18 or less when these alkyl group and alicyclic hydrocarbon group are combined. The group formed by combining an alkyl group and an aromatic hydrocarbon group preferably has a total carbon number of 18 or less when these alkyl group and aromatic hydrocarbon group are combined. R a02 and R a03 R and R are preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group which may have a halogen atom. R a04is 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, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group which may have a halogen atom. R a6 and R a7 are each independently 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, 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.

[0026] Examples of the structural unit (a1-0) include structural units represented by any of formula (a1-0-1) to formula (a1-0-24) and structural units in which the methyl group corresponding to R a01 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 formula (a1-0-1) to formula (a1-0-10), formula (a1-0-13), formula (a1-0-14), formula (a1-0-19) to formula (a1-0-21) are preferred. TIFF2025097301000026.tif119160

[0027] 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 formula (a1-1-1) to formula (a1-1-7) and R a4A structural unit in which the methyl group corresponding to is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group is preferred, and a structural unit represented by any of formula (a1-1-1) to formula (a1-1-4) is more preferred. TIFF2025097301000027.tif38168

[0028] 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 the methyl group corresponding to R in the structural unit (a1-2) a5 A structural unit in which the methyl group corresponding to is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group, and a structural unit 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 preferred. TIFF2025097301000028.tif91163

[0029] When the resin (A) contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (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, even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin (A) contains the structural unit (a1-0), its content 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, yet even more preferably 30 mol% or more, and still even more preferably 35 mol% or more, based on all the structural units such as the resin (A). Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less. Specifically, 5 to 80 mol% is mentioned, preferably 5 to 75 mol%, 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, yet even more preferably 40 mol% or more, and still even more preferably 50 mol% or more, based on all the structural units such as the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, yet even more preferably 70 mol% or less, and still even more preferably 65 mol% or less. Specifically, 10 to 90 mol% is mentioned, 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%, yet even more preferably 20 to 70 mol%.

[0030] Examples of the structural unit having the group (2) in the structural unit (a1) include the structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as "structural unit (a1-4)"). TIFF2025097301000029.tif31118[In the formula (a1-4), all the symbols have the same meanings as described above.]

[0031] R a1 and R a17Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (a1-0) include the same as those exemplified by R in a01 and the like. R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a17 Examples of the alkoxy group in the formula include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The number of carbon atoms of the alkoxy group is preferably 1 to 4, more preferably 1 to 3, even more preferably a methoxy group or an ethoxy group, and most preferably a methoxy group. R a17 Examples of the alkoxyalkyl group in the formula 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 number of carbon atoms of the alkoxyalkyl group is preferably 2 to 8, more preferably 2 to 4, even more preferably a methoxymethyl group or an ethoxyethyl group, and most preferably a methoxymethyl group. R a17 Examples of the alkoxyalkoxy group in the formula 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 number of carbon atoms of the alkoxyalkoxy group is preferably 2 to 8, more preferably 2 to 4, and even more preferably a methoxyethoxy group or an ethoxyethoxy group. R a17 Examples of the alkylcarbonyl group in the formula include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 8, more preferably 2 to 4, even more preferably 2 to 3, and most preferably an acetyl group. R a17Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group may be 2 to 8, preferably 2 to 4, more preferably 2 to 3, and even more preferably an acetyloxy group. R a17 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0032] A a11 Examples of the alkanediyl group of A include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, and a dodecane-1,12-diyl group, and branched alkanediyl groups such as a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, a 2-methylbutane-1,4-diyl group, a heptane-1,6-diyl group, an octane-1,7-diyl group, a nonane-1,8-diyl group, a decane-1,9-diyl group, and an undecane-1,10-diyl group. The number of carbon atoms in 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, even still more preferably 1 to 3, and even more preferably 1 or 2. R a18 Examples of the alkyl group of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group. A a11When the -CH2- contained in the alkanediyl group is replaced by -O-, -CO- or -NR a18 , the number of carbon atoms before replacement shall be taken as the number of carbon atoms of the hydrocarbon group. A a11 Examples of the group in which -CH2- contained in the alkanediyl group of A is replaced by -O- or -CO- include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group (the group in which -CH2- contained in the alkanediyl group is replaced by -NR a28 -), an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkylamino group (the group in which -CH2- contained in the alkyl group is replaced by -NR a18 -), a peptide group (the group in which -CH2-CH2- contained in the ethylene group is replaced by -CO-NR a18 -), an alkanediyl-oxy group (the group in which any -CH2- contained in the alkanediyl group is replaced by -O-), an alkanediyl-oxycarbonyl group (the group in which any -CH2-CH2- contained in the alkanediyl group is replaced by -O-CO-), an alkanediyl-carbonyl group (the group in which any -CH2- contained in the alkanediyl group is replaced by -CO-), an alkanediyl-carbonyloxy group (the group in which any -CH2-CH2- contained in the alkanediyl group is replaced by -CO-O-), an alkanediyl-sulfonyl group (the group in which any -CH2- contained in the alkanediyl group is replaced by -SO2-), an alkanediyl-thio group (the group in which any -CH2- contained in the alkanediyl group is replaced by -S-), an alkanediyl-amino group (the group in which any -CH2- contained in the alkanediyl group is replaced by -NR a18 -), 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 methylamino group, ethylamino group, propylamino group, butylamino group, pentylamino group, hexylamino group, octylamino group and the like. 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 methyleneamino group, ethyleneamino group, propyleneamino group and the like. 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 Examples of the group in which -CH2- contained in the alkanediyl group of A a18 is replaced by -O-, -CO- or -NR a12 - include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a12 -CO-O-, *-O-CO-A a12 -O-, *-O-A a12 -CO-O-, *-CO-O-A a12 -O-CO-, *-O-CO-A a18 -O-CO-, *-CO-NR a12 -CO-O-, *-CO-O-A a12 -CO-O-, *-CO-NR a18 - are preferable. 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 the same alkanediyl group as A a11 within the range where the upper limit of the number of carbon atoms permits. A a11 is a single bond, *-CO-O- or *-CO-O-A a12It 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-. 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.

[0033] R a34 、R a35 and R a36 Examples of the hydrocarbon group in R, R and R include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group and the like. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, 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 following groups (* represents the bonding site). Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a phenanthryl group and the like. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, etc. In particular, R a36 Examples of R 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. a35 Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms formed by R a36 and R a34 being bonded to each other and 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 TIFF2025097301000031.tif15105

[0034] Examples of R a34 are preferably a hydrogen atom. Examples of R a35 are preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. Examples of the hydrocarbon group of R a36 are preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. R a36The alkyl group and alicyclic hydrocarbon group in are preferably unsubstituted. R a36 The aromatic hydrocarbon group in preferably has an aromatic ring having an aryloxy group with 6 to 10 carbon atoms.

[0035] -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.

[0036] Examples of the structural unit (a1-4) include structural units derived from the monomers described in JP-A-2010-204646. Preferably, the structural units represented by the formulas (a1-4-1) to (a1-4-42) and R in the structural unit (a1-4) a1Examples of the structural unit in which the hydrogen atom corresponding thereto is replaced with a halogen atom, a haloalkyl group or an alkyl group include, 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). TIFF2025097301000032.tif228165

[0037] When the resin (A) contains the structural unit (a1-4), its content 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 60 mol% with respect to the total of all the structural units of the resin (A).

[0038] 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)"). TIFF2025097301000033.tif4558[In formula (a1-5), all the symbols have the same meanings as described above.]

[0039] R a8 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 above for R in formula (a1-0). 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 of them is -O- and the other is -S-. s1 is preferably 1. s1' is preferably any integer from 0 to 2. Z a1is preferably a single bond or *-CH2-CO-O-.

[0040] 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. TIFF2025097301000034.tif33133

[0041] When the resin (A) contains the structural unit (a1-5), the content thereof is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, even more preferably 10 mol% or more, still even more preferably 20 mol% or more, and 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.

[0042] 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)"). TIFF2025097301000035.tif3479[In formula (a1-6), all the symbols have the same meanings as described above.]

[0043] R a61 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 formula (a1-0) of R R a61is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group. R a62 , R a63 , R a64 and R a65 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group or an ethyl group. R a62 , R a63 and R a64 The cyclic hydrocarbon group in the formula (I) includes an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, and a norbornyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, and more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group and a naphthylene group. Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. R a62 and R a63 Examples of the ring formed by bonding with each other include an adamantane ring, a cyclopentane ring, and a cyclohexane ring. a62 and R a63 When they are bonded to each other to form a ring, -C(R a62 )(R a63 )(R a64Examples of the group include the following groups. * represents the bonding site with an oxygen atom. The number of carbon atoms in the ring is preferably 3 to 16, more preferably 3 to 12. TIFF2025097301000036.tif32110

[0044] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in L and L 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 a61 is preferably a single bond or -CO-O-*, more preferably a single bond. X a62 is preferably a single bond or *-O-L a61 -, more preferably a single bond.

[0045] Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms in Ar include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, and a phenanthrylene group. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group.

[0046] Examples of the halogen atom include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, 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. Examples of the substituent include a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, 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, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, more preferably a phenylene group which may have a hydroxy group.

[0047] Examples of the structural unit (a1-6) include structural units represented by formula (a1-6-1) to formula (a1-6-44), etc., preferably structural units represented by formula (a1-6-1) to formula (a1-6-9), more preferably 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), and even more preferably structural units represented by formula (a1-6-1) or formula (a1-6-2). TIFF2025097301000037.tif227164

[0048] 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), the hydrogen atom corresponding to R a61 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), the methyl group corresponding to R a61 replaced by a hydrogen atom, a halogen atom, a haloalkyl group, etc. are also included as the structural unit (a1-6).

[0049] 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, based on all the structural units of the resin (A). Also, 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, and even more preferably 60 mol% or less can be mentioned. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 7 to 70 mol%, still more preferably 7 to 65 mol%, and particularly preferably 10 to 60 mol%.

[0050] Also, as the structural unit (a1), the following structural units can also be mentioned. TIFF2025097301000038.tif33167

[0051] 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 still more preferably 50 mol% or more, based on all the structural units of the resin (A) etc. Also, 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 still more preferably 60 mol% or less can be mentioned. Specifically, it 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%.

[0052] Also, as the structural unit (a1), the following structural units can also be mentioned. When the resin (A) etc. contain structural units represented by the 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 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, 10 to 60 mol% is preferable, 15 to 55 mol% is more preferable, 20 to 50 mol% is still more preferable, 20 to 45 mol% is even more preferable, and 20 to 40 mol% is particularly preferable.

[0053] 〈Structural unit(s)〉 The structural unit(s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer(s)"). As the monomer 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) include 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.

[0054] 〈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 phenolic carboxy group. TIFF2025097301000040.tif4094[In the formula (a2), R a2 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO- or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 4 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 4. When na2 is 2 or more, a plurality of Ls a22 may be the same as or different from each other.

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

[0056] A a21Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, 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 the -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 the -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 - can be mentioned. Among them, *-CO-O-, *-CO-O-A a22 -CO-O- or *-O-A a22 -CO-O-, *-CO-NR a28 - are preferred. Here, A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site bonded to the carbon atom to which R a2 is bonded. The alkanediyl group of A a22 includes the same alkanediyl group as A a21 within the range 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-.

[0057] L a21 The hydrocarbon group in is a (na2 + 1)-valent hydrocarbon group, and examples thereof include a chain hydrocarbon group, an alicyclic hydrocarbon group of a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.), and a cyclic hydrocarbon group such as an aromatic hydrocarbon group. 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 include a divalent to hexavalent chain hydrocarbon group such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, an alkanepentayl group, and an alkanhexayl group. L a21 Examples of the alkanediyl group of include, for example, the same alkanediyl group as A a21 L a21 Examples of the alkanetriyl group of include a methanetriyl group, an ethanetriyl group, a propanetriyl group, a butanetriyl group, a pentanetriyl group, a hexanetriyl group, a heptanetriyl group, an octanetriyl group, a nonanetriyl group, a decanetriyl group, an undecanetriyl group, a dodecanetriyl group, a tridecanetriyl group, a tetradecanetriyl group, a pentadecanetriyl group, a hexadecanetriyl group, and a heptadecanetriyl group. Examples of the alkanetetrayl group include a methanetetrayl group, an ethanetetrayl group, a propanetetrayl group, a butanetetrayl group, a pentanetetrayl group, a hexanetetrayl group, a heptanetetrayl group, an octanetetrayl group, a nonanetetrayl group, a decanetetrayl group, an undecanetetrayl group, a dodecanetetrayl group, a tridecanetetrayl group, a tetradecanetetrayl group, a pentadecanetetrayl group, a hexadecanetetrayl group, and a heptadecanetetrayl group. ​Examples of the alkane pentyl group include a methane pentyl group, an ethane pentyl group, a propane pentyl group, a butane pentyl group, a pentane pentyl group, a hexane pentyl group, and the like. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. L a21 The number of carbon atoms of the chain hydrocarbon group of L is preferably from 1 to 18, more preferably from 1 to 12, still more preferably from 1 to 10, even more preferably from 1 to 9, still even more preferably from 1 to 8, still more preferably from 1 to 6, still even more preferably from 1 to 5, and particularly preferably from 1 to 4. L a21 Examples of the monocyclic and polycyclic divalent alicyclic hydrocarbon groups in L include the following alicyclic hydrocarbon groups and the like. The bonding site can be at any position. TIFF2025097301000041.tif46168 For example, divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkane pentyl group, a cycloalkanehexyl group, and the like can be mentioned. Specifically, monocyclic alicyclic hydrocarbon groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclooctane-1,5-diyl group, a cyclopropanetriyl group, a cyclobutanetriyl group, a cyclopentanetriyl group, a cyclohexanetriyl group, a cycloheptanetriyl group, a cyclooctanetriyl group, a cyclodecanetriyl group, a cyclopropanetetrayl group, a cyclobutanetetrayl group, a cyclopentanetetrayl group, a cyclohexanetetrayl group, a cycloheptanetetrayl group, a cyclooctanetetrayl group, a cyclodecanetetrayl group, and Examples of the polycyclic alicyclic hydrocarbon group include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, decahydronaphthalenediyl group, bicyclo[3.3.0]octanediy group, norbornanetril group, adamantanetril group, decahydronaphthalenetril group, bicyclo[3.3.0]octanetril group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, bicyclo[3.3.0]octanetetrayl group, and the like. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site, and the like. 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. a21 Examples of the aromatic hydrocarbon group in [compound name] include divalent to hexavalent aromatic hydrocarbon groups such as arylene group, arenetricyl group, arenetetrayl group, arenepentayl group, arenexayl group, and the like. Specifically, phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, benzenetricyl group, naphthalenetricyl group, anthracenetricyl group, biphenylenetricyl group, phenanthrenetricyl group, benzenetetrayl group, naphthalenetetrayl group, anthracenetetrayl group, biphenylenetetrayl group, phenanthrenetetrayl group, and the like can be mentioned. 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, the aromatic hydrocarbon group, and the chain hydrocarbon group may be combined with each other. Further, any group may be bonded to A a21 and L a22 . Examples of the trivalent to pentavalent alicyclic hydrocarbon group and aromatic hydrocarbon group include groups in which 1 to 3 hydrogen atoms are removed from the above-described divalent group to form a bond. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -SO2-), an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group,Examples include an aromatic hydrocarbon group-carbonyl oxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group formed by combining two or more of these groups. Also included are groups in which one or more hydrogen atoms of these groups are replaced at the bonding site. These replaced groups include, within the range permitted by the upper limit of the number of carbon atoms, those similar to the groups exemplified in this specification.

[0058] As for the group in which -CH2- contained in an alicyclic hydrocarbon group and a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, those similar to the groups exemplified in this specification are included within the range permitted by the upper limit of the number of carbon atoms. L a21 The hydrocarbon group in L may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the haloalkyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-). 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 L 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 L includes a branched structure, whereby 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 of the alkyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, and even still more preferably 1 to 3. L a21 is substantially a group in which -CH2- contained in the hydrocarbon group of L is replaced by -O-, -CO-, -S- or -SO2-. a21 can substantially have substituents such as a hydroxy group, a carboxy group, a thiol group, a sulfonyl group, an alkoxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, and the like. The number of carbon atoms of 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 of 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 of 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- or -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 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-). Preferably, it is 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 a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 6 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-).

[0059] L a22Examples of the chain hydrocarbon group having 1 to 12 carbon atoms include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-dimethylpropane-1,3-diyl group, pentane-2,4-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc. The number of carbon atoms in 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- are the same as those exemplified in the present specification. L a22 The fluorine atom(s) 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. TIFF2025097301000042.tif67164

[0060] When producing a resist pattern from the resist composition of the present invention, when using a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) as an exposure light source, as the structural unit (a2), a structural unit (a2) having a phenolic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-A) described later. When using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-1) described later. The structural unit (a2) may be included alone by 1 type, or may be included by 2 types or more.

[0061] In the structural unit (a2), L a21 In the case where is a cyclic hydrocarbon group, examples of the structural unit having a phenolic hydroxy group or a carboxy group include the structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF2025097301000043.tif30128[In the formula (a2-A), all the symbols have the same meanings as described above respectively.] R a2 and A a21 are the same groups as those exemplified by the formula (a2), respectively. 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, 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, more preferably an acetyl group. R a27 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R 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 ethoxyethoxy 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, more preferably 1 or 2. na21 is preferably 0, 1, or 2, 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, 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, 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, more preferably bonded to the 5th or 6th position.

[0062] 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 formulae (a2-2-1) to (a2-2-32) and formulae (a2-3-1) to (a2-3-24), and structural units in which the methyl group corresponding to R in the structural unit (a2-A) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. a2 TIFF2025097301000044.tif107170

[0063] 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

[0064] In structural unit (a2), L a21 When it is a cyclic hydrocarbon group, examples of the structural unit having an alcoholic hydroxy group or a carboxy group include a structural unit represented by formula (a2-B) (hereinafter sometimes referred to as "structural unit (a2-B)"), a structural unit represented by formula (a2-C) (hereinafter sometimes referred to as "structural unit (a2-C)"), or a structural unit represented by formula (a2-D) (hereinafter sometimes referred to as "structural unit (a2-D)"). TIFF2025097301000046.tif45100[In formula (a2-B) and formula (a2-C), R a2 represents the same meaning as in formula (a2). R a27 represents the same meaning as in formula (a2-A). L a25 is -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 X 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 R 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 ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. 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.

[0065] 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 the formula is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Among them, the structural units represented by any of formula (a2-B-1) to formula (a2-B-5) and formula (a2-C-1) to formula (a2-C-9) are preferable. When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on all the structural units of the resin (A). Further, it is 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, still more preferably 20 mol% or less, and even more preferably 10 mol% or less. Specifically, 1 to 45 mol% is mentioned, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, still more preferably 1 to 20 mol% or 2 to 20 mol%, and even more preferably 1 to 10 mol% or 2 to 10 mol%.

[0066] 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)"). TIFF2025097301000048.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 the plurality of parentheses may be the same as or different from each other. nD22 represents an integer of any one of 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 group of R and R 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, and the like. R a21 and R a22 are preferably a trifluoromethyl group. L a24 Examples of the alkanediyl group of L include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, and the like. L a24 is preferably a single bond or a methylene group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, a C1-C4 alkyl group which may have a halogen atom, a C1-C4 alkoxy group or a C2-C8 alkoxyalkoxy group, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxy-methoxy group, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nD2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, still more preferably 1 or 2, and even more preferably 1. Also preferably, nD2 is 1 and the group in parentheses is bonded to the para position. nD22 is preferably an integer of any one of 0 to 3, more preferably an integer of any one of 0 to 2, still more preferably 0 or 1, and even more preferably 0.

[0067] 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)").

[0068] 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)"). TIFF2025097301000049.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.

[0069] Examples of the structural unit (a2-D) include the structural units described below. TIFF2025097301000050.tif62167

[0070] In 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.

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

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

[0073] The structural unit (a3) is preferably a structural unit represented by the formula (a3-1), the formula (a3-2), the formula (a3-3), or the formula (a3-4). These may be contained alone or in combination of two or more. JPEG2025097301000051.jpg48155[In the formula (a3-1), the formula (a3-2), the formula (a3-3), and the formula (a3-4), L a4 、L a5 and L a6 each independently represents a group represented by -O- or *-O-(CH2) k3 -CO-O- (where k3 represents an integer from 1 to 7). L a7 represents -O-, *-O-L a8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding position with the carbonyl group. R a18 、R a19 、R a20 and R a24 each independently represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 、R a23 and R a25 each independently represents a carboxy group, a cyano group or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents 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.

[0074] R a21 、R a22 、R a23 and R a25 Examples of the aliphatic hydrocarbon group in 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 、Ra20 and R a24 Examples of the halogen atom and the alkyl group which may have a halogen atom in include R of formula (a1-0) a01 and the like are the same as those exemplified above. L a8 and L a9 Examples of the alkanediyl group in include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group and the like. L a4 ~L a6 are each independently preferably -O- or, *-O-(CH2) k3 -CO-O-, where k3 is an integer of any one of 1 to 4, more preferably -O- and, *-O-CH2-CO-O-, still more preferably an oxygen atom. L a7 is preferably -O- or *-O-L a8 -CO-O-, more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. R a18 R a19 R a20 and R a24 are 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, still 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 are each independently preferably an integer of any one of 0 to 2, more preferably 0 or 1. w1 is preferably any integer from 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)’. TIFF2025097301000052.tif3848 (wherein R a24 , L a7 represents the same meaning as above.)

[0075] Examples of the structural unit (a3) include structural units derived from the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. Examples of the structural unit (a3) include structural units represented by any of formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2), formula (a3-3-1), formula (a3-3-2), and formula (a3-4-1) to formula (a3-4-12), and, in the above structural units, structural units in which the methyl groups corresponding to R a18 , R a19 , R a20 and R a24 are replaced by hydrogen atoms are preferred. TIFF2025097301000053.tif108164

[0076] 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 even more preferably 25 mol% or less, and still 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.

[0077] 〈Structural unit (a4)〉 The structural unit represented by the formula (a4) is shown below. TIFF2025097301000054.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 saturated hydrocarbon group may be replaced by -O- or -CO-.

[0078] 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 monocyclic alicyclic saturated hydrocarbon groups which are monocyclic cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic saturated hydrocarbon groups which are polycyclic cycloalkyl groups 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 TIFF2025097301000055.tif10146 include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, such as -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group. 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, and 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, and 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 included 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, and groups formed by combining two or more of these groups. These replaced groups include those similar to the groups exemplified in this specification as long as the upper limit of the number of carbon atoms permits.

[0079] 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, may be referred to as "structural unit (a4-1)"), a structural unit represented by the formula (a4-2) (hereinafter, may be referred to as "structural unit (a4-2)"), a structural unit represented by the formula (a4-3) (hereinafter, may be referred to as "structural unit (a4-3)"), and a structural unit represented by the formula (a4-A) (hereinafter, may be referred to as "structural unit (a4-A)"). The structural unit represented by the formula (a4-1) is the structural unit shown below. TIFF2025097301000056.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.]

[0080] 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 [description] 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, and an octane-1,8-diyl group having a fluorine atom; Examples of the branched alkanediyl group having a fluorine atom include 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, and 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 [description] 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, and a cyclooctane-1,5-diyl group having a fluorine atom, Examples of the polycyclic cycloalkanediyl group having a fluorine atom include a norbornane-1,4-diyl group having a fluorine atom, a norbornane-2,5-diyl group having a fluorine atom, a 5-norbornene-2,3-diyl group having a fluorine atom, an adamantane-1,5-diyl group having a fluorine atom, and an adamantane-2,6-diyl group having a fluorine atom. L 42f The number of fluorine atoms of the alkanediyl group having a fluorine atom and the cycloalkanediyl group having a fluorine atom in [description] may be 1 or more, and preferably 2 or more. L42f The alkanediyl group and the cycloalkanediyl group having a fluorine atom in are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

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

[0082] L 41 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms, more preferably a single bond, a methylene group or an ethylene group, and 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.

[0083] As the structural unit (a4-1), the structural units shown below and the methyl group corresponding to R in the structural unit (a4-1) in the following structural units 41 in which the methyl group is replaced by a hydrogen atom are exemplified. The structural unit represented by the formula (a4-2) is the structural unit shown below. TIFF2025097301000058.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 43f L and 43f R has a fluorine atom, and the upper limit of the total number of carbon atoms of 43f L and 43f R is 21.]

[0084] Examples of the saturated hydrocarbon group in 43f L and 43f R include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these. Examples of the saturated hydrocarbon group in 43f L and 43f R are, as long as the upper limit of the total number of carbon atoms of 43f L and 43f R permits, R in the formula (a4)42 Examples of the aliphatic hydrocarbon group of 42 include the same groups as the exemplified aliphatic hydrocarbon groups.

[0085] L 43f As the saturated hydrocarbon group of 43f , an alkanediyl group having 1 to 6 carbon atoms or a group represented by the formula (L43f-1) is preferable. TIFF2025097301000059.tif14120[In the formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represent a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. L 47f represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. X 46f and X 47f each independently represent -O-, -CO-, -CO-O- or -O-CO-. However, the total number of carbon atoms 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 .]

[0086] Examples of the divalent aliphatic hydrocarbon group represented by L 45f , L 46f and L 47f in the group represented by the formula (L43f-1) include linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic hydrocarbon groups, and divalent saturated 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. may be mentioned. s is preferably 0.

[0087] 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. TIFF2025097301000060.tif47140

[0088] 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). TIFF2025097301000061.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 is 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 and A 43f and 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, 42 includes saturated hydrocarbon groups similar to the aliphatic hydrocarbon groups exemplified by 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, 43fB includes saturated hydrocarbon groups similar to the saturated hydrocarbon groups exemplified by R in formula (a4). 42 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 fluoroalkanediyl group having 1 to 6 carbon atoms. R 43fBThe aliphatic hydrocarbon group which may have a fluorine atom is preferably a chain hydrocarbon group, an alicyclic hydrocarbon group or a combination thereof which may have a fluorine atom, more preferably an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or a combination thereof which may have a fluorine atom, and trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, pentyl group, hexyl group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group and perfluorooctyl group and other alkyl fluoride groups, cyclopropylmethyl group, cyclopropyl group, cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantylmethyl group and the like are more preferable.

[0089] 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). TIFF2025097301000062.tif15170

[0090] 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. TIFF2025097301000063.tif99167

[0091] Examples of the structural unit represented by formula (a4-2B) include the following structural units and structural units in which the methyl group corresponding to R in the following structural units is replaced by a hydrogen atom. 41 Examples thereof include a structural unit in which the methyl group corresponding to R in the structural unit represented by formula (a4-2B) is replaced by a hydrogen atom. TIFF2025097301000064.tif111163

[0092] Examples of the structural unit (a4) also include a structural unit represented by formula (a4-3). TIFF2025097301000065.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 aliphatic 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 carbon number of L 44f and R 44f is 21.]

[0093] Examples of the aliphatic hydrocarbon group in L 44f and R 44f 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 44f and R 44f include, as long as the upper limit of the total carbon number of L 44f and R 44f allows, groups similar to the aliphatic hydrocarbon groups exemplified as the aliphatic hydrocarbon group of R 42 in formula (a4). L 44fis preferably an alkanediyl group having 1 to 14 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 - or -(CH2) j4 -CO-O-(CH2) j5 - (where j1 to j5 each independently represent an integer of 1 to 6). More preferably, it is an alkanediyl group having 1 to 4 carbon atoms (where one -CH2- contained in the alkanediyl group may be replaced by -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced by -CO-O- or -O-CO-). R 44f is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, an alicyclic hydrocarbon group having 3 to 10 carbon atoms having a fluorine atom, or a group combining them, still more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms having a fluorine atom.

[0094] 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 TIFF2025097301000066.tif86170

[0095] Examples of the structural unit (a4) also include a structural unit represented by the formula (a4-A). TIFF2025097301000067.tif3686 [In the formula (a4-A), R 1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 11 represents a single bond or *-CO-O-. * is R​1 represents the bonding site with the carbon atom to which it is bonded. L 1 represents an aliphatic hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. R 2 represents a fluorinated alkyl group having 1 to 8 carbon atoms. R 3 represents a hydrogen atom or a fluorinated alkyl group having 1 to 6 carbon atoms, and the fluorinated alkyl group may be bonded to L 1 to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-. mi represents any integer from 1 to 4. When mi is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other.]

[0096] R 1 Examples of the halogen atom and the alkyl group which may have a halogen atom in R include the same ones as those exemplified by R of formula (a1-0) to formula (a1-2). a01 R a4 and R a5 and the same ones as those exemplified by R of formula (a1-0) to formula (a1-2) are included. R 1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0097] L 1 Examples of the aliphatic hydrocarbon group in L include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.) alicyclic hydrocarbon group, and a group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group) may also be used. Examples of the chain hydrocarbon group include divalent to pentavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, and an alkanpentayl group. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Examples also include groups in which one or more hydrogen atoms of the above-described groups are replaced with bonding sites. The number of carbon atoms in 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.

[0098] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups, etc. The bonding site can be at any position. TIFF2025097301000068.tif45164For example, divalent to pentavalent alicyclic hydrocarbon groups such as cycloalkanediyl group, cycloalkanetriyl group, cycloalkanetetrayl group, and cycloalkanepentayl group, etc. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group, and Examples of the polycyclic alicyclic hydrocarbon group include a spiro ring 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]octanediy group, a spirocyclohexane-1,2'-cyclopentane-diyl group, a spiroadamantane-2,3'-cyclopentane-diyl group, etc., a norbornanediyl group or an adamantanediyl group, and a cycloalkanediyl group spiro-bonded thereto respectively. Also, examples include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, and even more preferably 3 to 12.

[0099] Examples of the group combined with two or more kinds include a group combining an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more kinds of the alicyclic hydrocarbon group and the chain hydrocarbon group may be combined respectively. Also, any group may be bonded to X 11 . Examples of a group combining an alicyclic hydrocarbon group and a chain hydrocarbon group include a group in which an alicyclic hydrocarbon group is bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which an alicyclic hydrocarbon group, a chain hydrocarbon group, and an alicyclic hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group, an alicyclic hydrocarbon group, and a chain hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), and the like. * represents the bonding site to X. 11 Also, examples include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site.

[0100] L 1 In the aliphatic hydrocarbon group having 1 to 28 carbon atoms in L, -CH2- may be replaced with -O-, -S-, -SO2- or -CO-. L 1 When -CH2- contained in the aliphatic hydrocarbon group having 1 to 28 carbon atoms in L is replaced with -O-, -S-, -SO2- or -CO-, the number of carbon atoms before replacement is defined 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 allowed by the upper limit of the number of carbon atoms. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced by a bonding site. 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.

[0101] L 1 The aliphatic hydrocarbon group in L may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms (the -CH2- contained in the alkyl group or the alicyclic hydrocarbon 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, 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. Examples of the alicyclic hydrocarbon group having 3 to 18 carbon atoms include monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, and polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, 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, and still more preferably 3 to 10. Examples of the aromatic hydrocarbon group having 6 to 18 carbon atoms include phenyl group, naphthyl group, biphenyl group, anthryl group, phenanthryl group, binaphthyl group, and the like. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 14, more preferably 6 to 12, and still more preferably 6 to 10. When -CH2- contained in an alkyl group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the alkyl group. Examples of the replaced group include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, and the like. L 1 Examples of the substituent that the aliphatic hydrocarbon group in 1 may have include 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-). A fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-) is more preferable. A fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group is even more preferable. L 1 is R 3When 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 (provided that -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.

[0102] R 2Examples of the C1-C8 fluoroalkyl group 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, and 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 When the C1-C6 fluoroalkyl group in is, as long as the upper limit of the number of carbon atoms permits, the C1-C6 fluoroalkyl groups listed in the examples of the R 2 fluoroalkyl group are similarly listed. R 2 is, when R 3 is a C1-C6 fluoroalkyl group, 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. R2 is, when R 3 is a hydrogen atom, preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride group having 1 to 5 carbon atoms, and still more preferably an alkyl fluoride group having 3 to 5 carbon atoms. R 3 is L 1 and combines to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, R 3 is L 1 Examples of the group formed by combining with L 2 include, for example, groups represented by the following formulas. Among the following formulas, * and ** represent bonding sites, and the two ** represent, 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 3 is L 1 and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. The number of carbon atoms of the alicyclic hydrocarbon group formed by combining R TIFF2025097301000069.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.

[0103] Examples of the structural unit (a4-A) include the following structural units and the like. In the following structural units, structural units in which the methyl group corresponding to R 1 is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or an alkyl group other than a methyl group, and structural units in which the hydrogen atom corresponding to R 1 is replaced with a halogen atom, a haloalkyl group, or an alkyl group can also be cited as specific examples of the structural unit (a4-A). TIFF2025097301000070.tif192167

[0104] 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.

[0105] 〈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). TIFF2025097301000071.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 an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0106] R 52 The alicyclic hydrocarbon group in 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 etc. 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 etc. R 52is 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 55 Examples of the divalent saturated hydrocarbon group in 55 include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and 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.

[0107] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by 55 is replaced by -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. TIFF2025097301000072.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents a bonding site with L x1 and represents a bonding site with L). 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 x4represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, L x3 and L x4 have a total carbon number of 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, L x5 , L x6 and L x7 have a total carbon number of 15 or less. In formula (L1-4), L x8 and L x9 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, L x8 , L x9 and W x1 have a total carbon number of 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 x6is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0108] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF2025097301000073.tif36147 Examples of the group represented by the formula (L1-2) include the following divalent groups. TIFF2025097301000074.tif23130 Examples of the group represented by the formula (L1-3) include the following divalent groups. TIFF2025097301000075.tif16147 Examples of the group represented by the formula (L1-4) include the following divalent groups. TIFF2025097301000076.tif13168L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0109] Examples of the structural unit (a5-1) include the following structural units and the structural units in the following structural units where the methyl group corresponding to R in the structural unit (a5-1) is replaced by a hydrogen atom. 51 are mentioned. When the resin (A) contains the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and still more preferably 3 to 15 mol% based on all the structural units of the resin (A).

[0110] 〈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-.

[0111] Examples of the sultone ring include the rings represented by 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. TIFF2025097301000078.tif3077

[0112] The sultone ring may have a substituent, and examples of the substituent include 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, and an alkylcarbonyl group having 2 to 4 carbon atoms.

[0113] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and a decyl group. Preferably, it is an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group. Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. Preferably, a trifluoromethyl group is included. Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a hydroxyalkyl group such as a 2-hydroxyethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkoxycarbonyl group include a group in which an alkoxy group such as a methoxycarbonyl group or an ethoxycarbonyl group is bonded to a carbonyl group, preferably an alkoxycarbonyl group having 6 or fewer 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 preferable.

[0114] As the sultone ring, a ring represented by the following formula (T1') is preferable. TIFF2025097301000079.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, and more preferably a methylene group. R 41 includes the same groups 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, and more preferably 0.

[0115] Examples of the ring represented by formula (T1’) include the following rings. The bonding site can be at any position. Among them, the bonding site is preferably at the 1-position or 3-position. TIFF2025097301000080.tif44147-Structural units having a -SO2- group preferably further have 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 structural unit (a6) is preferably a monomer having an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer.

[0116] Structural unit (a6) is preferably a structural unit represented by formula (a6-0). TIFF2025097301000081.tif4077[In 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.

[0117] Rx Examples of the halogen atom of x include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R x Examples of the alkyl group of x include, for example, 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, it is an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group. R x Examples of the alkyl group having a halogen atom of x include, for example, 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, etc. R x R 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. A x Examples of the divalent saturated hydrocarbon group of x 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 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; Monocyclic divalent alicyclic saturated hydrocarbon groups that are cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; Polycyclic divalent 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. can be mentioned. A x The bonding position to the sultone ring of

[0118] Examples of the structural unit (a6-0) include the following structural units. TIFF2025097301000082.tif93150

[0119] 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 preferable, and the structural units represented by formula (a6-1), formula (a6-2), formula (a6-7) and (a6-8) are more preferable. When the resin (A) has the structural unit (a6), its content is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, and further preferably 3 to 30 mol% based on all the structural units of the resin (A).

[0120] <Structural unit (a7)> The resin (A) etc. may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"). Specific examples of the structural unit (a7) include the structural units described in JP-A-2016-79235, and it is preferably a structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain or a structural unit having a sulfonio group and an organic anion in the side chain.

[0121] 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 the formula (a7-A). TIFF2025097301000083.tif26124[In the formula (a7-A), R a7 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 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-, and *** represents the bonding site with L a71 . na7 represents an integer of 0 to 2. When na7 is 2, the groups in the plurality of parentheses may be the same as or different from each other. RA - represents a sulfonate anion or a carboxylate anion. ZA + represents an organic cation.]

[0122] 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 of formula (a1-0) a01 include the same ones as those exemplified above. R a7 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.

[0123] X a71 When X is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025097301000084.tif3251[In formula (X10), Ax represents a bonding species that binds to the carbon atom to which R a7 is bonded, and represents one or more bonding species selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. Ay represents a bonding species that binds 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, the 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, -CO-NR a71It is preferably a bond represented by -. The bonding position of Ay in the phenylene group is preferably the m-position or p-position with respect to the bonding position of Ax, and more preferably the p-position. Among them, Rx is preferably a fluorine atom, iodine atom, trifluoromethyl group, methyl group or ethyl group. mx is preferably 0, 1 or 2. X a71 Examples of it include, for example, a single bond, the following formula (X 10 -1) to formula (X 10 -10). * represents the bonding site with the carbon atom to which -R a7 is bonded. ** represents the bonding site with L a71 . X 20 represents -O- or -NR a71 -. TIFF2025097301000085.tif43162 Formula (X 10 -1) to formula (X 10 -10) include the following groups as specific examples. TIFF2025097301000086.tif87163 Among them, X 10 is preferably a single bond or a group represented by formula (X 10 -1’) and formula (X 10 -3’) to formula (X 10 -10’), more preferably a single bond or a group represented by formula (X 10 -1’), formula (X 10 -4’), formula (X 10 -5’), formula (X 10 -6’) and formula (X 10 -10’), and even more preferably a single bond, a group represented by formula (X 10 -1’), a group represented by formula (X 10 -5’) or a group represented by formula (X 10 -6’).

[0124] L a71As the hydrocarbon group, one hydrogen atom is removed from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, and the group that binds to X a71 and X a72 is mentioned. Also, as the hydrocarbon group of L a72 one hydrogen atom is removed from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, and the group that binds to X a72 and RA - is mentioned. L a71 and L a72 As the chain hydrocarbon group, a group obtained by removing one hydrogen atom from an alkyl group or an alkenyl group is mentioned. As the alkyl group, it may be linear or branched, and specifically, the same groups as those described as the chain hydrocarbon group of X 0 are 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. L a71 and L a72 As the alicyclic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocyclic or polycyclic cycloalkyl group is mentioned. As the monocyclic cycloalkyl group, a cyclobutyl group, a cyclopentane group, a cyclohexane group, a cyclopentyl group, a cyclooctyl group, etc. are mentioned. L a71 and L a72Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include a norbornyl group and an adamantyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of the ring in which two rings are spiro-bonded include a spirocycloalkyl 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. 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 represented by the following formula can be given. TIFF2025097301000087.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. L a71 and L a72 Examples of the aromatic hydrocarbon group of L 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, and a fluorene group. 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 L and 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 a71 and L a72Among 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 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, and the like. These replaced groups include those similar to the groups exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. L a71 and L a72 Among the hydrocarbon groups, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group and the group combining the alicyclic hydrocarbon group and the aromatic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include those similar to those exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. L a71 and L a72 Among the hydrocarbon groups, -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 combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and 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. The above combined groups are included. The group 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 may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. La71 and L a72 When 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 possessed by the alicyclic hydrocarbon group or the aromatic hydrocarbon group. Also, L b1‘ and L b2‘ When -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 group of 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. na7 is preferably 0 or 1. ZA in the formula (a7-A) + is the same as the cation Z1 in the salt represented by the formula (B1) described later + and the like can be mentioned.

[0125] Examples of the structural unit represented by the formula (a7-A) include the following structural units, R a7 Structural units in which a group corresponding to the methyl group of 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 structural units described in WO 2012 / 050015. ZA + represents an organic cation. TIFF2025097301000088.tif130157

[0126] TIFF2025097301000089.tif244163

[0127] 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). TIFF2025097301000090.tif27104[In the formula (a7-B), R a7represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A II1 represents a single bond or a divalent linking group. R II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. R II2 and R II3 each independently represent a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, and R II2 and R II3 may combine with each other to form a ring together with the sulfur atom to which they are attached. A - represents an organic anion. R a7 Examples of the halogen atom and the alkyl group which may have a halogen atom of R include the same halogen atom and the alkyl group which may have a halogen atom as those in formula (a7-A). R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by R include a phenylene group and a naphthylene group. R II2 and R II3 Examples of the hydrocarbon group represented by R and R include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the alkyl group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and the group formed by combining these are the same as those described above. A II1 Examples of the divalent linking group represented by A include a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S-, or -CO-. Examples of the divalent saturated hydrocarbon group include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and combinations thereof. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. can be mentioned. 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. TIFF2025097301000091.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.]

[0128] Examples of the structural unit containing the cation in formula (a7-B) include the structural unit represented below and a group corresponding to the methyl group of R a7 wherein the group corresponding to the methyl group of R is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.), and the like. JPEG2025097301000092.jpg72163

[0129] A - Examples of the organic anion represented by A include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion. A - The organic anion represented by A is preferably a sulfonate anion, and more preferably an anion contained in the salt represented by formula (B1) described below. Examples of the sulfonylimide anion, the sulfonylmethide anion, and the carboxylate anion are the same as those exemplified as the anion of the acid generator (B).

[0130] Examples of the structural unit represented by formula (a7-B) include the structural unit represented below. TIFF2025097301000093.tif95157

[0131] When the resin (A) contains the structural unit (a7), the structural unit (a7) may be contained alone or in combination of two or more. The content ratio 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).

[0132] The resin (A) is preferably a resin composed of the structural unit (IP), the structural unit (a1), and the structural unit (s), that is, a copolymer of the compound (I), the monomer (a1), and the monomer (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2), the structural unit (a1-4), the structural unit (a1-5), and the structural unit (a1-6); more preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2), the structural unit (a1-4), and the structural unit (a1-5); still more preferably at least one selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2); and even more preferably at least two selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by the formula (a2-A) or a structural unit represented by the formula (a2-D). 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).

[0133] Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers that lead to these structural units. The content 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), 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less), but may contain oligomers having a weight average molecular weight smaller than this. In this specification, the weight average molecular weight is a value determined by gel permeation chromatography under the conditions described in the examples.

[0134] <Resin other than resin (A)> The resist composition of the present invention may contain a resin other than the resin (A). Examples of the resin other than the resin (A) include a resin (AX) having the same structural units as the resin (A) except for not containing the structural unit (a1) in the resin (A) described above, a resin (AA) having the same structural units as the resin (A) except for not containing the structural unit (I) in the resin (A) described above, a resin containing the structural unit (a4) and / or the structural unit (a5) (however, not containing the structural unit (IP) and the structural unit (a1); hereinafter sometimes referred to as "resin (X)"), and the like. Examples of the resin (AA) include a resin composed of the structural unit (a1) and the structural unit (s), that is, a copolymer of the monomer (a1) and the monomer (s). Examples of the resin (AX) include a resin containing the structural unit (a2), preferably a resin containing the structural unit (a2-A), and more preferably a resin containing the structural unit (a2-A) and the structural unit (a2-B). In the resin (AX), the content of the structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, and still more preferably 15 mol% or more, based on the total of all the structural units of the resin (AX). Also, it is preferably 80 mol% or less, and more preferably 70 mol% or less. In the resin (AX), the content of the structural unit (a2-B) is preferably 5 mol% or more, more preferably 10 mol% or more, and still more preferably 15 mol% or more, based on the total of all the structural units of the resin (AX). Also, it is preferably 80 mol% or less, and more preferably 70 mol% or less. In the resin (AX), the content of the structural unit (a2-B) is preferably greater than the content of the structural unit (a2-A). Examples of the structural units that the resin (X) may further have include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. Among them, the resin (X) is preferably a resin composed only of the structural unit (a4) and / or the structural unit (a5), and more preferably a resin composed only of the structural unit (a4). When the resin (X) contains the structural unit (a4), in the resin (X), the content of the structural unit (a4) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, still more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. When the resin (X) contains the structural unit (a5), the content of the structural unit (a5) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, still more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. Further, when the resin (X) contains the structural unit (a4) and the structural unit (a5), the total content of the structural unit (a4) and the structural unit (a5) is 40 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, and still more preferably 80 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less. Specifically, it is 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and still more preferably 80 to 100 mol%. 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, and more preferably 30:70 to 70:30 or 40:60 to 60:40. Each structural unit constituting resin (AA), resin (AX), and resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers that induce these structural units. The content of each structural unit of resin (AA), resin (AX), and resin (X) can be adjusted by the amount of monomers used in the polymerization. The weight average molecular weight of resin (AA), resin (AX), and 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 resin (X) is the same as that for resin (A) and the like.

[0135] When the resist composition of the present invention contains resin (AA), resin (AX), or resin (X), the content thereof 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, respectively, based on 100 parts by mass of resin (A) and the like.

[0136] The content of resin (A) in the resist composition is preferably 60% by mass or more and 99% by mass or less, more preferably 65% by mass or more and 99% by mass or less, based on the solid content of the resist composition. Also, the total content of resin (A) is preferably 60% by mass or more and 99% by mass or less, more preferably 65% by mass or more and 99% by mass or less, based on the solid content of the resist composition. When containing resins other than resin (A), the total content of resins other than resin (A) is preferably 5% by mass or more and 80% by mass or less, preferably 10% by mass or more and 70% by mass. The total content of resin (A) and resins other than 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 relative thereto can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0137] <Acid generator (B)> The resist composition of the present invention contains an acid generator (B1). TIFF2025097301000094.tif1392[wherein all the symbols are the same as above.] L b1 As the (nb1 + 1)-valent hydrocarbon group of L, nb1 hydrogen atoms are removed from a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent group combining two or more of these groups, and a group that binds to one or more L b2 is mentioned. The number of carbon atoms of the hydrocarbon group is preferably 1 to 48, more preferably 1 to 42, still more preferably 1 to 36, even more preferably 1 to 30, even further preferably 1 to 24, and even more preferably 1 to 18. As the chain hydrocarbon group, a group obtained by removing nb1 hydrogen atoms from an alkyl group or an alkenyl group is mentioned. The alkyl group may be linear or branched, and specifically, L a71 and L a72 are the same groups as those described as the chain hydrocarbon groups of. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 20, and still 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 is mentioned. As the monocyclic cycloalkyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, etc. are mentioned. Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include a norbornyl group and an adamantyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of the cycloalkyl group in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. Further, a double bond may be formed between two carbon atoms included in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include those represented by the following formula. TIFF2025097301000095.tif26168 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, still more preferably 3 to 18, even more preferably 3 to 12, even more preferably 3 to 10, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms of the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, still more preferably 6 to 18, even more preferably 6 to 12, and even more preferably 7 to 12. Examples of the aromatic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a fluorenyl group. More specifically, examples of the aromatic hydrocarbon group include those represented by the following formula. As for the number of carbon atoms in the aromatic hydrocarbon group in TIFF2025097301000096.tif1085, it is preferably 4 to 24, more preferably 4 to 20, still more preferably 4 to 18, even more preferably 5 to 14, still even more preferably 5 to 10, and even more preferably 6 to 10. L b1 When -CH2- contained in the hydrocarbon group of b1 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 b1 Among the hydrocarbon groups of b1 , examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an 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-), and the like. These replaced groups include, within the range permitted by the upper limit of the number of carbon atoms, the same groups as those exemplified in this specification. L b1 Among the hydrocarbon groups of b1 , as groups in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2-, groups including structures such as cyclic ethers, cyclic ketones, cyclic esters (lactones), cyclic thioethers, cyclic acetals, cyclic sulfonic acid esters (sultones), etc. can be mentioned. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding position of the alicyclic hydrocarbon groups listed in the following formulas can be any position. TIFF2025097301000097.tif48165L b1 Among the hydrocarbon groups of b1 , -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and as groups in which -CH2- is replaced by -O- or -S-, groups derived from a furan ring or a thiophene ring, etc. can be mentioned respectively. Specifically, aromatic hydrocarbon groups represented by the following formulas can be mentioned. TIFF2025097301000098.tif1326As groups in which -CH2- contained in a group combining an alicyclic saturated hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, within the range permitted by the upper limit of the number of carbon atoms, the same groups as those exemplified in this specification can be mentioned. As groups combining two or more of a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group, groups combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, groups combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, groups combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and groups combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group can be mentioned. As a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group, a condensed ring may be used. L b2 Examples of the divalent hydrocarbon group of b2 include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group combining two or more of these groups. One hydrogen atom is removed from the monovalent hydrocarbon group, and Yb1 Examples of the group that binds to L b2 The divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group formed by combining two or more of these groups of L b1 include groups obtained by removing one hydrogen atom from the monovalent chain hydrocarbon group, monovalent alicyclic hydrocarbon group, monovalent aromatic hydrocarbon group, and monovalent group formed by combining two or more of these, exemplified by L b1 and L b2 Examples of the substituent that the hydrocarbon group of L b1 and L b2 may have include halogen atoms, cyano groups, nitro groups, etc. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, iodine atom, etc. b1 and L b2 When b1 and L b2 are groups 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 aromatic hydrocarbon group has. Further, when the -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of Y b1 Examples of the cyclic hydrocarbon group of Y b1 include alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. b1 The alicyclic hydrocarbon group and aromatic hydrocarbon group of Y b1Examples of the substituent that the methyl group may have include a halogen atom, a cyano group, a hydroxy group, a nitro group, etc. Y b1 Examples of the substituent that the cyclic hydrocarbon group of b1 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, or a nitro group. The -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. Y b1 The number of carbon atoms of the hydrocarbon group that the cyclic hydrocarbon group of Y b1 does not include the number of carbon atoms of the cyclic hydrocarbon group. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these groups. Examples of the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group combining two or more of these groups include, within the range permitted by the upper limit of the number of carbon atoms, L b1 the same groups as those exemplified for the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group combining two or more of these groups exemplified by b1 . Also, Y b1 Examples of the group in which -CH2- contained in the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent is replaced by -O-, -S-, -CO-, or -SO2- include, within the range permitted by the upper limit of the number of carbon atoms, the same groups as those exemplified for the group in which -CH2- contained in the hydrocarbon group of Lb1 is replaced by -O-, -S-, -CO-, or -SO2-. Also, Y b1 The hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent may constitute a protecting group or a leaving group (an acid-labile group or a base-labile group) generally used in the art. Examples of the anion of the salt represented by formula (B1) include, for example, an anion represented by the following formula (B1-A1) (hereinafter sometimes referred to as "anion (B1-A1)") or an anion represented by formula (B1-A2) (hereinafter sometimes referred to as "anion (B1-A2)"). TIFF2025097301000099.tif31125[In formula (B1-A1), L b2 and Y b1 have the same meaning as in formula (B1). Q b1 、Q b2 、Q b3 and Q b4 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. z1 represents any integer from 0 to 6. When z1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. X 1 represents -O-CO-, -CO-O-, -O-CO-O-, or -O-. L b3 represents a single bond or an (nb2 + 1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. nb2 represents any integer from 1 to 3. When nb2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other.] Q b1 、Q b2 、Q b3 and Q b4 Examples of the alkyl group of Q b1 、Q b2 、Q b3 and Q b4 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 and Q b2 are b1 Q b2It is preferably included in at least one of them, a fluorine atom or a perfluoroalkyl group, more preferably a fluorine atom or a perfluoroalkyl group, still more preferably a fluorine atom or a trifluoromethyl group, and even more preferably both are fluorine atoms. Q b3 and Q b4 are each independently preferably 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.

[0138] z1 is preferably any integer from 0 to 3, and more preferably 0, 1 or 2. X 1 is preferably -O-CO- or -CO-O-.

[0139] L b3 As the hydrocarbon group in, within the range allowed by the upper limit of the number of carbon atoms, the same hydrocarbon groups as exemplified for L in formula (B1) can be mentioned. b1 are mentioned. L b3is preferably a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), an optionally substituted aromatic hydrocarbon group having 6 to 10 carbon atoms (wherein -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-), or a group formed by combining two or more of these groups, and more preferably a single bond, a chain hydrocarbon group having 1 to 6 carbon atoms or a group represented by the following formula (Lb3-1). When -CH2- contained in the chain hydrocarbon group is replaced by -O- or -CO-, the number thereof is preferably 1 to 4, and preferably, one -CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO- or -CO-O-, or one -CH2-CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO-O-. TIFF2025097301000100.tif1682[In the formula (Lb3-1), nb2 represents the same meaning as the formula (B1-A1). L b31 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent. W b3 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent. * and ** represent bonding sites, and * represents the bonding site with X 1 and represents the bonding site with.] In the formula (Lb3-1), L b31 's chain hydrocarbon group, as long as the upper limit of the number of carbon atoms permits, L b1Examples thereof include the same groups as the chain hydrocarbon groups exemplified above. In formula (Lb3-1), W b3 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of, as long as the upper limit of the number of carbon atoms permits, are the same groups as the alicyclic hydrocarbon groups and the aromatic hydrocarbon groups exemplified by L b1 Examples thereof include the same groups as the alicyclic hydrocarbon groups and the aromatic hydrocarbon groups exemplified above. In formula (Lb3-1), L b31 The substituents that the chain hydrocarbon group of may have and W b3 The substituents that the alicyclic hydrocarbon group and the aromatic hydrocarbon group of may have are the same groups as the substituents exemplified as the substituents that the hydrocarbon group of L b1 may have. L b31 is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, the alicyclic hydrocarbon group and the aromatic hydrocarbon group of W b3 are preferably the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below. In the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below, * and ** represent the bonding sites, * represents the bonding site with X 1 or L b31 and ** represents a hydrogen atom, a substituent or the bonding site with L b2 and at least one ** represents the bonding site with L b2 In addition, in the alicyclic hydrocarbon group represented below, the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. When the -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, it is preferably a ether ring, an ester ring (lactone), a carbonate ester ring, a sulfonic acid ester ring (sultone) or an acetal ring. In formula (B1-A1), L b2is a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), 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 which represents a chain hydrocarbon group having 1 to 6 carbon atoms, and the other represents a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms. X 2 represents -O-, -CO-O-, -O-CO- or -O-CO-O-. * and ** represent bonding sites, and ** represents the bonding site with Y b1 However, the total carbon number of L b21 , X 2 and L b22 is 12 or less.) is more preferable. In formula (B1-A1), Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, it is preferably a group represented by the following formula (Y1) to formula (Y36). In formula (Y1) to formula (Y36), R Yb represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms among the substituents 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 L b2represents a binding site to. The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formula are not particularly shown in the following formula, but may have substituents that the cyclic hydrocarbon group of Y b1 may also have. TIFF2025097301000102.tif84158

[0140] As the anion represented by the formula (B1-A1), anions represented by the formulas (B1-A1-1) to (B1-A1-85) [hereinafter, may be referred to as "anion (B1-A1-1)" etc. according to the formula number] are preferable, and anions represented by any of the formulas (B1-A1-1) to (B1-A1-4), formula (B1-A1-9), formula (B1-A1-10), formulas (B1-A1-24) to (B1-A1-33), formulas (B1-A1-36) to (B1-A1-40), and formulas (B1-A1-47) to (B1-A1-85) are more preferable. TIFF2025097301000103.tif216161

[0141] TIFF2025097301000104.tif249151

[0142] TIFF2025097301000105.tif254163

[0143] Here, R i2 ~R i7 are, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 represent the same meaning as above. As the anion represented by the formula (B1-A1), specifically, the anions described in JP-A-2010-204646 can be mentioned.

[0144] Preferred anions represented by the formula (B1-A1) include anions represented by the formula (B1a-1) to the formula (B1a-70), respectively. TIFF2025097301000106.tif185163

[0145] TIFF2025097301000107.tif252166

[0146] TIFF2025097301000108.tif70166

[0147] Among them, anions represented by any of the formula (B1a-1) to the formula (B1a-3), the formula (B1a-7) to the formula (B1a-19), and the formula (B1a-22) to the formula (B1a-70) are preferred.

[0148] The anion represented by the formula (B1-A2) is represented by the following formula. TIFF2025097301000109.tif23100[In the formula (B1-A2), L b2 and Y b1 have the same meaning as in the formula (B1). R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl group may be replaced by -O- or -CO-. nb4 represents any integer from 1 to 5. When nb4 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. nb3 represents any integer from 0 to 4. When nb3 is 2 or more, the plurality of R b1 may be the same as or different from each other. However, 1 ≦ nb4 + nb3 ≦ 5 is satisfied.]

[0149] In the formula (B1-A2), L b2 hydrocarbon group of and Yb1 Examples of the cyclic hydrocarbon group of L in formula (B1) include those within the range permitted by the upper limit of the number of carbon atoms b2 of the hydrocarbon group of Y b1 and are the same as the examples of the cyclic hydrocarbon group of Y b2 Examples of the hydrocarbon group of L b1 and the substituents that the methyl group and the cyclic hydrocarbon group of Y may have are also the same as the examples of the substituents that the hydrocarbon group of L b2 of formula (B1), the methyl group of Y b1 and the cyclic hydrocarbon group may have. These hydrocarbon groups, methyl groups, and cyclic hydrocarbon groups may have one substituent or a plurality of substituents. In formula (B1-A2), L b2 is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), 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 the bonding site with the benzene ring to which SO3 - is bonded. L b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms.) and even more preferably *-CO-O-. Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and Y b1 or L b1It is more preferable that it is an alicyclic hydrocarbon group or an aromatic hydrocarbon group exemplified above. Specifically, it is preferably a group represented by the above-described formulas (Y1) to (Y36), and more preferably a group represented by the above-described formulas (Y1) to (Y19). 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 is preferably bonded at the m-position of the benzene ring with respect to the bonding position of SO3 - in the following structure.

[0150] 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 is preferably bonded at the m-position of the benzene ring with respect to the bonding position of SO3 - in the following structure. TIFF2025097301000110.tif28107[In the above formula, L b2 , Y b1 , R b1 , and nb3 have the same meanings as in formula (B1-A2).] In formula (B1-A2), when n4b is 2 or more, a plurality of L b2 and Y b1 preferably represent the same group as each other.

[0151] Examples of the alkyl group having 1 to 6 carbon atoms for R b1 include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, and hexyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, and more preferably 1 to 3. Examples of the halogen atom for R b1 include fluorine atom, chlorine atom, bromine atom, and iodine atom. Examples of the group in which -CH2- contained in the alkyl group is replaced by -O- or -CO- include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an oxy group, a carbonyl group, and the like. These replaced groups include those similar to the groups exemplified in the present specification as long as the upper limit of the number of carbon atoms permits. 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, and 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.

[0152] Examples of the anion represented by formula (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. The following anions have some R b1is omitted and may contain substituents not shown in the figure. TIFF2025097301000111.tif95162

[0153] In another form of the acid generator (B), an anion in which the anion represented by the formula (B1) is replaced with a sulfonimide anion, a sulfonylmethide anion, or a carboxylic acid anion is also preferably used as the acid generator (B). Examples of the sulfonylimide anion and the sulfonylmethide anion include the following. TIFF2025097301000112.tif1289[In the 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 is formed. 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 the formula (B1-A3), L b2’ and Y b1’ Examples of the hydrocarbon group, the cyclic hydrocarbon group, and their substituents of are the same groups as L b2 and Y b1 in the formula (B1-A1). In the formula (B1-A3), L b2’ is a single bond, *-L b23 -X2 - 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, and X 2 and X 3 each independently represent -O-, -CO-O-, -O-CO-, -O-CO-O- or -O-, and W 2 represents an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-, and * represents a bonding site with SO2.) is preferable. 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.

[0154] 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. TIFF2025097301000113.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 b4 The disulfonylimide ring or the disulfonylmethide ring of W is preferably having 3 to 6 carbon atoms, and the hydrogen atom of the methylene group contained in the ring is preferably replaced by a fluorine atom.

[0155] 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. Examples of the carboxylic acid anion include the following. TIFF2025097301000115.tif41155

[0156] 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, etc. Among these, organic sulfonium cations and organic iodonium cations are preferable, and arylsulfonium cations or aryliodonium 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. TIFF2025097301000116.tif82160[In the formulas (b2-1) to (b2-5), R b4 ~R b6 each independently represents a chain 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 chain 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 b5They 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 by -O-, -S- or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of any one of 0 to 5. When m2 is 2 or more, a plurality of R b7 may be the same or different, and when n2 is 2 or more, a plurality of R b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may 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 by -O-, -S- or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the 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 may be bonded to each other to form a ring including -CH-CO- to which they are bonded, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 and Rb21 ~R b26 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b13 and R b14 and R b21 and R b22 may 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 by -O-, -S- or -CO-. R b27 ~R b29 each independently represents a hydrogen atom or a group containing an acid-labile group. L b31 and L b41 ~L b43 each independently represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of any one of 0 to 5. q2 and r2 each independently represent an integer of any one of 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, a plurality of R b13 are the same or different, when p2 is 2 or more, a plurality of R b14 are the same or different, when q2 is 2 or more, a plurality of R b15 are the same or different, when r2 is 2 or more, a plurality of R b16 are the same or different, when s2 is 2 or more, a plurality of R b17 are the same or different, when t2 is 2 or more, a plurality of R b18 are the same or different. u3 represents an integer of any one of 1 to 3, and satisfies 1 ≦ u3 + q23 ≦ 5. u4 and u5 each independently represent an integer of any one of 0 to 3, and satisfy 0 ≦ u4 + o21 ≦ 5 and 0 ≦ u5 + p22 ≦ 5. o21, p22, q23, r24, t25, and s26 each independently represent an integer of any one of 0 to 4. When u3, u4, and u5 are each 2 or more, the groups in parentheses are each the same or different. When o21, p22, q23, r24, t25, and s26 are each 2 or more, the 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.

[0157] The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, and 2-ethylhexyl group. In particular, the chain hydrocarbon group of R b9 ~R b12 is preferably C1-C12. 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. TIFF2025097301000117.tif11157 In particular, R b9 ~R b12 The alicyclic hydrocarbon group of ~R preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

[0158] Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methylnorbornil group, an isobornyl group, and the like. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The alkyl fluoride group represents an alkyl group having 1 to 12 carbon atoms and having a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a perfluorobutyl group. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4.

[0159] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples of the aromatic hydrocarbon group having a chain hydrocarbon group include a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group, and examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group include a p-cyclohexylphenyl group and a p-adamantylphenyl group. When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as benzyl group, phenethyl group, phenylpropyl group, trityl group, naphthylmethyl group, and naphthylethyl group.

[0160] Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group, and dodecyloxy group. Examples of the alkylcarbonyl group include acetyl group, propionyl group, and butyryl group. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, and iodine atom. 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, and 2-ethylhexylcarbonyloxy group.

[0161] R b4 and R b5 The ring formed by R TIFF2025097301000118.tif24142

[0162] R b9 and R b10The ring formed by combining them may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. For example, thiolan-1-ium ring (tetrahydrothiophenium ring), thian-1-ium ring, 1,4-oxathian-4-ium ring and the like can be mentioned. R b11 and R b12 The ring formed by combining them may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring and the like. R b27 ~R b29 Examples of the group containing an acid-labile group of ~R c30 include -R c30 or -L c10 -CO-O-R c30 represented by (L c10 represents an alkanediyl group having 1 to 6 carbon atoms, and R c30 represents an acid-labile group.). R b27 ~R b29 As the acid-labile group, for example, represents the above-mentioned group (1) or group (2).

[0163] Among cations (b2-1) to cations (b2-5), preferably, it is cation (b2-1), cation (b2-4) or cation (b2-5). Examples of the cation (b2-1) include cations represented by Formula (b2-c-1) to Formula (b2-c-27), Formula (b2-c-47) to Formula (b2-c-53), and Formula (b2-c-59) to Formula (b2-c-64). Examples of the cation (b2-2) include cations represented by Formula (b2-c-28) to Formula (b2-c-30) and Formula (b2-c-50). Examples of the cation (b2-3) include cations represented by Formula (b2-c-31) to Formula (b2-c-34). Examples of the cation (b2-4) include cations represented by Formula (b2-c-35) to Formula (b2-c-46), Formula (b2-c-54) to Formula (b2-c-58), and Formula (b2-c-65) to Formula (b2-c-68). Examples of the cation (b2-1) include the following cations represented by Formula (b2-c-69) to Formula (b2-c-79). TIFF2025097301000119.tif248162

[0164] TIFF2025097301000120.tif230164

[0165] The acid generator (B1) 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 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 the cation (b2-1), cation (b2-2), cation (b2-3), cation (b2-4), or cation (b2-5).

[0166] As the acid generator (B1), preferably those represented by Formula (B1-1) to Formula (B1-105), Formula (B2-1) to Formula (B2-20), and Formula (B3-1) to Formula (B3-28) can be mentioned. Among them, those containing an arylsulfonium cation are preferable, 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 preferable. TIFF2025097301000121.tif167165

[0167] TIFF2025097301000122.tif249155

[0168] TIFF2025097301000123.tif254165

[0169] TIFF2025097301000124.tif252160

[0170] TIFF2025097301000125.tif249163

[0171] TIFF2025097301000126.tif247150

[0172] TIFF2025097301000127.tif187159

[0173] In addition to the acid generator (B1), the resist composition of the present invention may also contain acid generators known in the art. As the acid generator (B), either a nonionic compound or an ionic compound may be used. Examples of nonionic compounds 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), etc. Representative examples of ionic compounds include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of anions of onium salts include sulfonic acid anion, benzenesulfonyl anion, sulfonylimide anion, sulfonylmethide anion, and carboxylic acid anion, etc.

[0174] In the resist composition of the present invention, the content of the acid generator is preferably 0.1% by mass or more and 99.9% by mass or less based on the solid content of the resist composition. Among them, the content of the acid generator (B1) is preferably 1% by mass or more and 45% by mass or less, more preferably 1% by mass or more and 40% by mass or less, and still more preferably 3% by mass or more and 35% by mass or less based on the solid content of the resist composition. Further, the content of the acid generator (B1) is preferably 1 part by mass or more and 50 parts by mass or less, more preferably 1 part by mass or more and 45 parts by mass or less, still more preferably 3 parts by mass or more and 40 parts by mass or less, and even more preferably 3 parts by mass or more and 35 parts by mass or less with respect to 100 parts by mass of the resin (A).

[0175] <Quencher (C)> The quencher (C) includes salts that generate an acid with a lower acidity than the acid generated from a basic nitrogen-containing organic compound or an acid generator (for example, acid generator (B1), acid generator (B), the same applies hereinafter). 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, still more preferably about 0.1 to 8% by mass, and even more preferably about 0.1 to 7% by mass based on the solid content of the resist composition. Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. Examples of the amine include aliphatic amines and aromatic amines. Examples of the aliphatic amine 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.

[0176] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator is indicated by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator 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 include a salt represented by the following formula, a salt 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 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). TIFF2025097301000128.tif97153

[0177] The weak acid inner salt (D) is preferably a diphenyliodonium salt having an iodonium cation to which two phenyl groups are bonded and a carboxylic acid anion substituted for at least one of the two phenyl groups bonded to the iodonium cation, and specifically, salts represented by the following formulas can be mentioned.

[0178] TIFF2025097301000129.tif1695 [In formula (D), R D1 and R D2 each independently represents 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 thereof 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 and the like. Examples of the group formed by combining these include alkyl-cycloalkyl groups, cycloalkyl-alkyl groups, aralkyl groups (e.g., 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, more preferably 0. When m' is 2 or more, the plurality of R D1 may be the same or different, and when n' is 2 or more, the plurality of R D2 may be the same or different.

[0179] More specifically, the following salts can be mentioned. TIFF2025097301000130.tif72165

[0180] <Photoinitiator (G)> The photoinitiator (G) includes, for example, an active radical generator that generates active radicals upon irradiation with light. Examples of the active radical generator include acetophenone-based photoinitiators, benzoin-based photoinitiators, benzophenone-based photoinitiators, thioxanthone-based photoinitiators, triazine-based photoinitiators, and the like. The photoinitiators (F) may each be used alone or in combination of two or more thereof.

[0181] Examples of the acetophenone-based photoinitiator include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]propan -1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-morpholino-1-(4-methylthiophenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, and an oligomer of 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propan-1-one. Examples of the benzoin-based photoinitiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and the like. Examples of the benzophenone-based photoinitiator include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3',4,4'-tetra(tert-butylperoxycarbonyl oxy)benzophenone, 2,4,6-trimethylbenzophenone, and the like. Examples of the thioxanthone-based photoinitiator include 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, and the like. Examples of the triazine-based photoinitiators include 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxynaphthyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-piperonyl-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(5-methylfuran-2-yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(furan-2-yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2- (4-diethylamino-2-methylphenyl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(3,4-dimethoxyphenyl)ethenyl]-1,3,5-triazine, and the like. As the radical generator, for example, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 10-butyl-2-chloroacridone, 2-ethylanthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methyl phenylglyoxylate, titanocene compounds, etc. can also be used. Examples of the radical generator include commercially available products such as the product name "Irgacure-907" (an acetophenone-based photoinitiator, manufactured by CIBA-GEIGY).

[0182] The resist composition of the present invention may contain a photoinitiator coagent. The photoinitiator coagent is a compound used in combination with a photoinitiator to promote the polymerization of the compound (I) initiated by the photoinitiator (G). Examples of the photoinitiator coagent include amine-based photoinitiator coagents, alkoxyanthracene-based photoinitiator coagents, etc. These may be used alone or in combination of two or more.

[0183] Examples of amine-based photopolymerization initiator aids include triethanolamine, methyldiethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 2-dimethyl aminoethyl benzoate, 2-ethylhexyl 4-dimethylaminobenzoate, N,N-dimethylparatoluidine, 4,4'-bis(dimethylamino)benzophenone (commonly known as Michler's ketone), 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(ethylmethylamino)benzophenone, and the like.

[0184] Examples of alkoxyanthracene-based photopolymerization initiator aids include 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 2-ethyl-9,10-diethoxyanthracene, and the like. Commercially available photopolymerization initiator aids can also be used. Examples of commercially available photopolymerization initiator aids include, for example, the product name "EAB-F" (manufactured by Hodogaya Chemical Co., Ltd.).

[0185] When the resist composition of the present invention uses a photopolymerization initiator (G), its content is preferably 3 parts by mass or more and 30 parts by mass or less, more preferably 5 parts by mass or more and 25 parts by mass or less, based on the solid content contained in the resist composition. When using a photopolymerization initiator aid, its content is usually 10 moles or less, preferably 0.01 mole or more and 5 moles or less, per mole of the photopolymerization initiator. The content of the photopolymerization initiator (G) and the photopolymerization initiator aid is preferably 3 parts by mass or more and 30 parts by mass or less, more preferably 5 parts by mass or more and 25 parts by mass or less, based on the solid content contained in the resist composition.

[0186] <Solvent (E)> The content rate 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, and more preferably 94% by mass or more and 99% by mass or less. The content rate of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography. Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; and the like. One kind of the solvent (E) may be used alone, or two or more kinds may be used.

[0187] 〈Other Components〉 The resist composition of the present invention may contain, if necessary, components other than the above-described components (hereinafter sometimes referred to as "other components (F)"). There is no particular limitation on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc., can be used. As a preferred embodiment of the resist composition of the present invention, a resist containing the resin (A), the acid generator (B1), and the quencher (C) is preferable, and a resist containing the resin (A) containing a structural unit having an acid-labile group, the acid generator (B1), and the quencher (C) is more preferable.

[0188] 〈Preparation of Resist Composition〉 The resist composition of the present invention can be prepared by mixing a resin (A) containing a structural unit derived from a compound represented by formula (I), an acid generator (B1), and, if necessary, a photopolymerization initiator (G), a resin other than the resin (A), a solvent (E), a quencher (C), and other components (F). The mixing order is arbitrary and 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. Note that the mixing means is also not particularly limited, and stirring and mixing, etc. can be used. After mixing the respective components, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

[0189] <Method for manufacturing a resist pattern> The method for manufacturing 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 (5) A step of developing the heated composition layer. To apply the resist composition onto a substrate, it can be carried out by a commonly used apparatus such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers and organic substrates having a resist film or the like formed on the surface. Before applying the resist composition, the substrate may be cleaned, or an antireflection film or the like may be formed on the substrate. By drying the applied composition, the solvent is removed to form a composition layer. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-bake), or by using a decompression device. The heating temperature is preferably 50 to 200 °C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during vacuum 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 emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region by wavelength-converting laser light from a solid laser light source (such as YAG or semiconductor laser), electron beams, those that irradiate extreme ultraviolet light (EUV), etc., various ones can be used. In the present specification, irradiating these radiations may 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 heat-treated (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. Chemical treatment (silylation) may be performed to adjust the hydrophilicity or hydrophobicity of the resin on the surface side of the composition after heating. Also, before development, the steps of coating, drying, exposing, and heating the resist composition may be repeatedly performed on the composition layer after exposure. The composition layer after heating is usually developed using a developing solution with a developing device. Examples of the developing method include the dip method, paddle method, spray method, dynamic dispense method, etc. The developing temperature is preferably, for example, 5 to 60 °C, and the developing time is preferably, for example, 5 to 300 seconds. By selecting the type of developing solution as follows, a positive resist pattern or a negative resist pattern can be manufactured. When manufacturing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developing solution. The alkaline developer may be various alkaline aqueous solutions used in this field. For example, aqueous solutions of tetramethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline), etc. may be mentioned. The alkaline developer may contain a surfactant. It is preferable to wash the developed resist pattern with ultrapure water and then remove the water remaining on the substrate and the pattern. When producing 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 developer") is used as the developer. Examples of the organic solvent contained in the organic 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; and aromatic hydrocarbon solvents such as anisole. In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and even more preferably substantially only the organic solvent. Among them, as the organic developer, a developer containing butyl acetate and / or 2-heptanone is preferable. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant. The organic developer may also contain a small amount of water. During development, development may be stopped by replacing with a solvent of a different type from the organic developer. It is preferable to wash the developed resist pattern with a rinse solution. The rinse solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After washing, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

[0190] 〈Use〉 The resist composition of the present invention is 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 suitable as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for semiconductor microfabrication.

Examples

[0191] The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing content or usage amount 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 + guard column (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 °C Injection volume: 100 μl Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

[0192] In addition, the structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC is Agilent 1100 type, MASS is Agilent LC / MSD type). In the following examples, the value of this molecular ion peak is indicated by “MASS”.

[0193] Synthesis Example 1: Synthesis of the compound represented by formula (I-1) 25 parts of the compound represented by formula (I-1-a), 200 parts of tetrahydrofuran, 25.27 parts of triethylamine, and 1.22 parts of dimethylaminopyridine were mixed and stirred at 23°C for 30 minutes, and then cooled to 5°C. To the resulting mixture, 30.23 parts of the compound represented by formula (I-1-b) was added over 30 minutes. After the temperature was raised to 23°C, the mixture was stirred at 23°C for 1 hour. To the resulting mixture, 300 parts of ethyl acetate and 100 parts of 10% aqueous potassium carbonate solution were added and stirred at 23°C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 100 parts of 5% aqueous oxalic acid solution was added and stirred at 23°C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 150 parts of ion-exchanged water was added and stirred at 23°C for 30 minutes, and then the layers were separated to obtain the organic layer. This water washing operation was repeated 5 times. By concentrating the obtained organic layer, 24.33 parts of the compound represented by formula (I-1) was obtained. MASS: 359.1 [M+H] +

[0194] Synthesis Example 2: Synthesis of the compound represented by formula (I-1m) 25 parts of the compound represented by formula (I-1-a), 200 parts of tetrahydrofuran, 25.27 parts of triethylamine, and 1.22 parts of dimethylaminopyridine were mixed and stirred at 23°C for 30 minutes, and then cooled to 5°C. To the resulting mixture, 36.96 parts of the compound represented by formula (I-1m-b) was added over 30 minutes. After the temperature was raised to 23°C, the mixture was stirred at 23°C for 1 hour. To the resulting mixture, 300 parts of ethyl acetate and 100 parts of 10% aqueous potassium carbonate solution were added and stirred at 23°C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 100 parts of 5% aqueous oxalic acid solution was added and stirred at 23°C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 150 parts of ion-exchanged water was added and stirred at 23°C for 30 minutes, and then the layers were separated to obtain the organic layer. This water washing operation was repeated 5 times. By concentrating the obtained organic layer, 30.27 parts of the compound represented by formula (I-1m) was obtained. MASS: 387.1 [M+H] +

[0195] Synthesis Example 3: Synthesis of the compound represented by formula (I-2) 1.64 parts of the compound represented by formula (I-2-a), 20 parts of tetrahydrofuran, 1.27 parts of triethylamine, 0.07 part of dimethylaminopyridine, and 2.47 parts of the compound represented by formula (I-2-b) were mixed and stirred at 23°C for 30 minutes, and then further stirred at 50°C for 1 hour. After the obtained mixture was cooled to 23°C, 100 parts of ethyl acetate and 30 parts of a 10% aqueous potassium carbonate solution were added, and the mixture was stirred at 23°C for 30 minutes and then separated to obtain the organic layer. To the obtained organic layer, 30 parts of a 5% aqueous oxalic acid solution was added, and the mixture was stirred at 23°C for 30 minutes and then separated to obtain the organic layer. To the obtained organic layer, 30 parts of ion-exchanged water was added, and the mixture was stirred at 23°C for 30 minutes and then separated to obtain the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and the concentrated mixture was fractionated using a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 1.89 parts of the compound represented by formula (I-2). MASS: 375.1 [M+H] +

[0196] Synthesis Example 4: Synthesis of the compound represented by formula (I-4m) 3.56 parts of the compound represented by TIFF2025097301000134.tif36158 formula (I-2m-a), 30 parts of tetrahydrofuran, 2.53 parts of triethylamine, 0.12 part of dimethylaminopyridine and 2.75 parts of the compound represented by formula (I-4m-b) were mixed and stirred at 23 °C for 30 minutes, and then further stirred at 50 °C for 1 hour. After the obtained mixture was cooled to 23 °C, 100 parts of ethyl acetate and 30 parts of 10% aqueous potassium carbonate solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 30 parts of 5% aqueous oxalic acid solution was added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 30 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and the concentrated mixture was fractionated using a column (silica gel 60N (spherical, neutral) 100 - 210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 2.48 parts of the compound represented by formula (I-4m). MASS:559.1[M+H] +

[0197] Synthesis Example 5: Synthesis of the compound represented by formula (I-3m) 39 parts of the compound represented by the formula (I-3-a), 200 parts of tetrahydrofuran, 25.27 parts of triethylamine and 1.22 parts of dimethylaminopyridine were mixed and stirred at 23 °C for 30 minutes, and then cooled to 5 °C. To the resulting mixture, 36.96 parts of the compound represented by the formula (I-1m-b) were added over 30 minutes, and after warming to 23 °C, the mixture was stirred at 23 °C for 1 hour. To the resulting mixture, 300 parts of ethyl acetate and 100 parts of a 10% aqueous potassium carbonate solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 100 parts of a 5% aqueous oxalic acid solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 150 parts of ion-exchanged water were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. This washing operation was repeated 5 times. The obtained organic layer was concentrated, and the concentrated mixture was fractionated using a column (silica gel 60N (spherical, neutral) 100 - 210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 35.88 parts of the compound represented by the formula (I-3m). MASS:527.1[M+H] +

[0198] Synthesis Example 6: Synthesis of the compound represented by the formula (I-31m) 41 parts of the compound represented by TIFF2025097301000136, formula (I-31-a), 200 parts of tetrahydrofuran, 25.27 parts of triethylamine and 1.22 parts of dimethylaminopyridine were mixed and stirred at 23 °C for 30 minutes, and then cooled to 5 °C. To the resulting mixture, 36.96 parts of the compound represented by formula (I-1m-b) were added over 30 minutes. After the temperature was raised to 23 °C, the mixture was stirred at 23 °C for 1 hour. To the resulting mixture, 300 parts of ethyl acetate and 100 parts of 10% aqueous potassium carbonate solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 100 parts of 5% aqueous oxalic acid solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 150 parts of ion-exchanged water were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. This washing operation was repeated 5 times. The obtained organic layer was concentrated, and the concentrated mixture was fractionated using a column (silica gel 60N (spherical, neutral), 100 - 210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 19.32 parts of the compound represented by formula (I-31m). MASS: 543.1 [M+H] +

[0199] Synthesis Example 7: Synthesis of the compound represented by formula (I-9) 2.50 parts of the compound represented by TIFF2025097301000137, formula (I-1-a), 244 parts of the compound represented by formula (I-9-b), 50 parts of acetonitrile and 4.15 parts of potassium carbonate were mixed and stirred at 23 °C for 30 minutes, and then the temperature was raised to 70 °C, and further stirred at 70 °C for 3 hours. To the resulting reaction product, 120 parts of chloroform and 60 parts of 5% aqueous oxalic acid solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the recovered organic layer, 60 parts of ion-exchanged water were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. This washing operation was repeated 5 times. The obtained organic layer was concentrated, and the concentrated mixture was fractionated using a column (silica gel 60N (spherical, neutral), 100 - 210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 3.88 parts of the compound represented by formula (I-9). MASS: 455.1 [M+H] +

[0200] Synthesis of Resin The compounds (monomers) used in the synthesis of the resin are shown below. TIFF2025097301000138.tif112165 or less, these compounds are referred to as "monomer (a1-2-6)" etc. according to the formula number.

[0201] Synthesis Example 8 [Synthesis of Resin A1] As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-1)] was mixed so as to be 40:56:4, and further, to this monomer mixture, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 mol% with respect to the total number of moles of all monomers, and this was heated at 85 °C for about 5 hours to carry out polymerization. Then, to the polymerization reaction solution, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of the total monomer amount was added, 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 with a weight average molecular weight of about 1.4×10 4 Resin A1 was obtained in a yield of 66%. This resin A1 has the following structural units. JPEG2025097301000139.jpg30135

[0202] Synthesis Example 9 [Synthesis of Resin A2] As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-1m) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-1m)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of all monomer amounts was added to the polymerization reaction solution, stirred for 6 hours, and then liquid-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. The weight average molecular weight was about 1.1×10 4 Resin A2 with a yield of 63% was obtained. This resin A2 has the following structural units. TIFF2025097301000140.tif30135

[0203] Synthesis Example 10 [Synthesis of Resin A3] As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-2) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-2)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of all monomer amounts was added to the polymerization reaction solution, stirred for 6 hours, and then liquid-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. The weight average molecular weight was about 1.2×10 4Resin A3 was obtained in a yield of 60%. This Resin A3 has the following structural units. TIFF2025097301000141.tif31135

[0204] Synthesis Example 11 [Synthesis of Resin A4] As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-4m) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-4m)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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 (2.5 wt%) 2.0 times the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was carried out. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby a resin A4 having a weight average molecular weight of about 1.5×10 4 was obtained in a yield of 66%. This Resin A4 has the following structural units. TIFF2025097301000142.tif34166

[0205] Synthesis Example 12 [Synthesis of Resin A5] As monomers, monomer (a2-B-1), monomer (a1-2-6) and monomer (I-1m) were used, and they were mixed so that the molar ratio [monomer (a2-B-1): monomer (a1-2-6): monomer (I-1m)] was 40:56:4. Further, propylene glycol monomethyl ether at 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A5 having a weight average molecular weight of about 1.0×10 4 and having a yield of 68%. This resin A5 has the following structural units. TIFF2025097301000143.tif30135

[0206] Synthesis Example 13 [Synthesis of Resin A6] As monomers, monomer (a2-2-1), monomer (a1-2-6) and monomer (I-1m) were used, and they were mixed so that the molar ratio [monomer (a2-2-1): monomer (a1-2-6): monomer (I-1m)] was 40:56:4. Further, propylene glycol monomethyl ether at 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin A6 having a weight average molecular weight of about 1.2×10 4 and having a yield of 72%. This resin A6 has the following structural units. TIFF2025097301000144.tif36138

[0207] Synthesis Example 14 [Synthesis of Resin A7] As monomers, 4-acetoxystyrene, monomer (a1-6-8) and monomer (I-1m) were used, and they were mixed so that the molar ratio [4-acetoxystyrene: monomer (a1-6-8): monomer (I-1m)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 12 hours, liquid separation was carried out. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and resin A7 having a weight average molecular weight of about 1.2×10 4 was obtained in a yield of 68%. This resin A7 has the following structural units. TIFF2025097301000145.tif31135

[0208] Synthesis Example 15 [Synthesis of Resin A8] As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-3m) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-3m)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of the total monomer amount was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was carried out. 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, and resin A8 having a weight average molecular weight of about 1.6×10 4 was obtained in a yield of 77%. This resin A8 has the following structural units. TIFF2025097301000146.tif33166

[0209] Synthesis Example 16 [Synthesis of Resin A9] As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-31m) were used and mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-31m)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was carried out. 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 with a weight average molecular weight of about 1.2×10 4 Resin A9 was obtained in a yield of 70%. This Resin A9 has the following structural units. TIFF2025097301000147.tif33166

[0210] Synthesis Example 17 [Synthesis of Resin A10] As monomers, 4-acetoxystyrene, monomer (a1-6-8) and monomer (I-9) were used, and they were mixed so that the molar ratio [4-acetoxystyrene: monomer (a1-6-8): monomer (I-9)] was 40:56:4. Further, propylene glycol monomethyl ether 2.6 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, 2,2'-azobis(isobutyric acid) dimethyl was added as an initiator so as to be 20 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. Thereafter, an aqueous solution of 25% tetramethylammonium hydroxide was added to the polymerization reaction solution, stirred for 12 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery with a yield of 66% of resin A10 having a weight average molecular weight of about 1.3×10 4 Resin A10 was obtained. This resin A10 has the following structural units. TIFF2025097301000148.tif37138

[0211] <Preparation of resist composition> As shown in Table 1, the following respective components were mixed, and the obtained mixture was filtered through a polyethylene resin filter having a pore size of 0.001 μm to prepare a resist composition.

Table 1

[0212] <Resin> A1~A10: Resin A1~Resin A10 <Acid generator> B1-62: Salt represented by formula (B1-62) (synthesized according to the examples of JP-A-2021-123579) TIFF2025097301000150.tif3185BX: (manufactured by Tokyo Chemical Industry Co., Ltd.) TIFF2025097301000151.tif2767<Quencher (C)> D1: (manufactured by Tokyo Chemical Industry Co., Ltd.) TIFF2025097301000152.tif1754 <Solvent> 400 parts of propylene glycol monomethyl ether acetate 100 parts of propylene glycol monomethyl ether 5 parts of γ-butyrolactone

[0213] (Electron Beam Exposure Evaluation of Resist Composition) A 6-inch silicon wafer was treated on a direct hot plate with hexamethyldisilazane at 90 °C for 60 seconds. The resist composition was spin-coated on this silicon wafer so that the film thickness of the composition layer was 0.04 μm. Then, it was prebaked on a direct hot plate at the temperature shown in the "PB" column of Table 1 for 60 seconds to form a composition layer. A contact hole pattern (hole pitch 40 nm / hole diameter 17 nm) was directly drawn on the composition layer formed on the wafer using an electron beam lithography machine ["ELS-F125 125 keV" manufactured by Elionix, Inc.] while changing the exposure dose step by step. After exposure, post-exposure baking was performed on a hot plate at the temperature shown in the "PEB" column of Table 1 for 60 seconds, and further paddle development was performed with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide for 60 seconds to obtain a resist pattern.

[0214] In the resist pattern obtained after development, the exposure dose at which the formed hole diameter became 17 nm was defined as the effective sensitivity.

[0215] <CD Uniformity (CDU) Evaluation> At the effective sensitivity, the hole diameter of the pattern formed with a hole diameter of 17 nm was measured 24 times for one hole, and the average value was taken as the average hole diameter of one hole. The standard deviation was obtained using, as the population, the average hole diameters of the patterns formed with a hole diameter of 17 nm measured at 400 locations within the same wafer. The results are shown in Table 2. The numerical values in the table indicate the standard deviation (nm).

Table 2

Industrial Applicability

[0216] The resist composition of the present invention has good CD uniformity (CDU) and is useful for semiconductor microfabrication.

Claims

1. A resist composition comprising a resin that includes a structural unit derived from a compound represented by formula (I) and an acid generator that includes a salt represented by formula (B1). [In formula (I), R １ , R ２ and R ３ each independently represents a halogen atom, a haloalkyl group having 1 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms, and —CH 2 - may be replaced by -O- or -CO-. R ４ and R ５ 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 １１ and X １２ Each independently represents -SO ２ -, -O-SO ２ -or-SO ２ It represents —O—. X ２１ and X ２２ each independently represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR ７ -**, *-NR ７ -CO-O-**, *-O-CO-NR ７ -** or *-Ax-Ph-Ay-**. R ７ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent binding sites, * represents R ４ Or R ５ represents the bonding site with the carbon atom to which it is bonded. n12 represents an integer of 0 to 4, and when n12 is 2 or more, the groups in the parentheses may be the same or different. m1 represents an integer of 0 to 4, and when m1 is 2 or more, a plurality of R １ may be the same or different from each other. m2 represents an integer of 0 to 4, and when m2 is 2 or more, a plurality of R ２ may be the same or different from each other. m3 represents an integer of 0 to 4, and when m3 is 2 or more, a plurality of R ３ may be the same or different. [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 with -. Y b1 represents a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and the —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.

2. X ２１ and X ２２ each independently represents a single bond or a group represented by the formula (X ２０ -1) ~Formula (X ２０ 2. The resist composition according to claim 1, wherein the aryl group is a group represented by any one of the following formulas: [Formula (X ２０ -1) ~ type (X ２０ -10) *, ** are binding sites, * is R ４ Or R ５ represents the bonding site with the carbon atom to which it is bonded. 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 an integer of 0 to 4. X ２０ is -O- or -NR ７ Represents -. R ７ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

3. The resist composition according to claim 1, wherein the resin containing a structural unit derived from the compound represented by formula (I) further contains 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), and a structural unit represented by formula (a1-5). [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. The alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may contain 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.]

4. 2. The resist composition according to claim 1, wherein the resin containing a structural unit derived from the compound represented by formula (I) further contains a structural unit represented by formula (a1-6). [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 a bond to -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 -, * represents a bond to -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.]

5. 2. The resist composition according to claim 1, wherein the resin containing a structural unit derived from the compound represented by formula (I) further contains 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 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.

6. 2. The resist composition according to claim 1, wherein the resin containing a structural unit derived from the compound represented by formula (I) further contains a structural unit represented by formula (a2-D). [In formula (a2-D), R ａ２ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and 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. R ａ２１ and R ａ２２ each independently represents a fluorinated alkyl group having 1 to 4 carbon atoms. L ａ２４ represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents an integer of 1 to 5. When nD2 is 2 or more, the groups in the parentheses may be the same or different. nD22 represents an integer of 0 to 4. When nD22 is 2 or more, a plurality of R ａ２７ may be the same or different.

7. 2. The resist composition according to claim 1, further comprising a salt capable of generating an acid having a weaker acidity than the acid generated from the acid generator.

8. (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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