Resist composition, method for producing resist pattern, and resin

Abstract

To provide a resin, a resist composition and the like which allow a resist pattern having a good pattern collapse margin to be produced.SOLUTION: A resist composition contains a resin containing a structural unit of a formula (I), a structural unit having a group of a formula (II-x), and a structural unit having an acid-labile group.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, a resin, and the like.

Background Art

[0002] Patent Document 1 describes a resist composition containing a resin having the following structural unit and a structural unit having an acid-labile group. TIFF2025081260000001.tif3354

[0003] Patent Document 2 describes a resist composition containing a resin having the following structural unit and a structural unit having an acid-labile group. TIFF2025081260000002.tif2421

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides a resist composition that forms a resist pattern having better pattern collapse resistance (PCM) than the resist pattern formed by the above resist composition.

Means for Solving the Problems

[0006] The present invention includes the following inventions. [1] A resist composition containing a resin including a structural unit represented by formula (I), a structural unit having a group represented by formula (II-x), and a structural unit having an acid-labile group. TIFF2025081260000003.tif52132[In formula (I), Q 1 and Q 2 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. R 21 and R 22 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents any integer from 0 to 6. When z is 2 or more, a plurality of R 21 and R 22 may be the same as or different from each other. X 1 represents *-CO-O-, *-O-CO-, *-O-CO-O-, or *-O-, where * represents a bonding site with C(R 21 )(R 22 ), or C(Q 1 )(Q 2 ). L 10 represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH 2 - contained in the hydrocarbon group may be replaced by -O-, -S-, -SO 2 -, or -CO-. mm1 represents 0 or 1. R 10 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. X 10 represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR 3 -**, *-NR 3 -CO-O-**, *-O-CO-NR 3 -**, or *-Ax-Ph-Ay-**. R 3 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 10 is bonded. Z1 + represents an organic cation. TIFF2025081260000004.tif2958[In formula (II-x), ring W 1 represents a heterocyclic ring having 2 to 36 carbon atoms, and the hydrogen atoms contained in the heterocyclic ring may be substituted with halogen atoms or hydrocarbon groups having 1 to 24 carbon atoms. The -CH 2 - in the heterocyclic ring and the hydrocarbon group may be replaced with an -O-, -S-, -CO-, or -NR c - group. R c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * represents a bonding site. [2]X 10 is a single bond or a group represented by formula (X 10 -1) to formula (X 10 -10) as described in [1] of the resist composition. TIFF2025081260000005.tif43162[In formula (X 10 -1) to formula (X 10 -10), *, ** are bonding sites, and * represents the bonding site with the carbon atom to which R 10 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 represents -O- or -NR 3 -. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. [3]L 10is a single bond, a chain hydrocarbon group having 1 to 10 carbon atoms which may have a substituent (provided that -CH 2 - in the chain hydrocarbon group may be replaced by -O- or -CO-), a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (provided that -CH 2 - in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -), or a group formed by combining a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent and a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (provided that -CH 2 - in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH 2 - in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO 2 - or -CO-).) The resist composition according to [1] or [2]. [4] The resist composition according to any one of [1] to [3], wherein the structural unit having a group represented by formula (II-x) is a structural unit represented by formula (IIA). TIFF2025081260000006.tif4056 [In formula (IIA), ring W 1 represents the same meaning as formula (II-x). 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 X represents a single bond, -A X1 -*, or -CO-O-A X1 -* (* represents the bonding site with the carbonyl group). A X1 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH 2 - in the saturated hydrocarbon group may be replaced by -O-, -CO- or -N(R d )-. R d represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.] [5] The resist composition according to any one of [1] to [4], wherein the structural unit having an acid-labile group 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), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). TIFF2025081260000007.tif44140In formula (a1-0), formula (a1-1), and formula (a1-2), L a01 、L a1 and L a2 each independently represents -O- or *-O-(CH 2 ) 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, and the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. m1 represents an integer of any one of 0 to 14. n1 represents an integer of any one of 0 to 10. n1’ represents an integer of any one of 0 to 3.] TIFF2025081260000008.tif31119[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 -CH 2 - 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 -CH 2 - 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. When na1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na11 represents any integer from 0 to 4. 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.] TIFF2025081260000009.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 *-(CH 2 ) 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. ] TIFF2025081260000010.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 the bonding site with Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 - or *-CO-O-L a62 -, * represents the bonding site with Ar, and L a61 and L a62 each independently represent an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. [6] The resist composition according to any one of [1] to [5], wherein the resin further contains a structural unit represented by the formula (a2-A). TIFF2025081260000011.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 -CH 2 - 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. [7] The resist composition according to any one of [1] to [6], further containing an acid generator, wherein the acid generator contains a salt represented by the formula (B1). TIFF2025081260000012.tif1492 [In the formula (B1), L b1represents a (nb1 + 1)-valent hydrocarbon group which may have a single bond or substituents, and -CH contained in the hydrocarbon group 2 - may be replaced by -O-, -S-, -CO- or -SO 2 -. L b2 represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or substituents, and -CH contained in the hydrocarbon group 2 - may be replaced by -O-, -S-, -CO- or -SO 2 -. Y b1 represents a methyl group which may have substituents or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have substituents, and -CH contained in the cyclic hydrocarbon group 2 - may be replaced by -O-, -S-, -SO 2 - 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. Z + represents an organic cation.] [8] The resist composition according to any one of [1] to [7], further containing a salt that generates an acid having a lower acidity than the acid generated from the structural unit represented by formula (I). [9](1) A step of applying the resist composition according to any one of [1] to [8] onto a substrate, (2) A step of drying the applied resist composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A method for producing a resist pattern, including a step of developing the heated composition layer.

[10] A resin containing the structural unit represented by the above-described formula (I), the structural unit having the group represented by the above-described formula (II-x), and the structural unit having an acid-labile group. [Effect of the Invention]

[0007] By using the resist composition of the present invention, a resist pattern can be produced with good pattern collapse resistance (PCM).

Mode for Carrying Out the Invention

[0008] In this specification, the “(meth)acrylic monomer” means “at least one of an acrylic monomer and a methacrylic monomer”. Expressions 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 -CH 2 - in a hydrocarbon group or the like being replaced by -O-, -S-, -CO- or -SO 2 - shall apply the same examples to each group, and the carbon number before replacement shall be taken as the carbon number of the hydrocarbon group or the like. The “combined group” means a group formed by bonding two or more of the exemplified groups, and the valences of those groups may be appropriately changed depending on the bonding form. “Derived from” or “induced from” refers to the polymerizable C═C bond contained in the molecule becoming a -C-C- group (single bond) by polymerization. When stereoisomers exist, all stereoisomers are included. Depending on the number of substituents and the like, any position and number of hydrogen atoms contained in each group may be replaced by a bonding site. The carbon number in the substituent is not included in the carbon number of the group to be substituted. In this specification, the “acid-labile group” means a group having a leaving group, which forms a hydrophilic group (for example, a hydroxy group or a carboxy group) when the leaving group is eliminated upon contact with an acid (for example, trifluoromethanesulfonic acid or the like). The “base-labile group” means a group having a leaving group, which forms a hydrophilic group (for example, a carboxy group or a hydroxy group) when the leaving group is eliminated upon contact with a base (for example, trimethylamine or the like). The “solid content of the resist composition” means the total of the components excluding the solvent (E) described later from the total amount of the resist composition.

[0009] 〔Resist Composition〕 The resist composition of the present invention contains a resin (hereinafter sometimes referred to as "resin (A)") that includes a structural unit represented by formula (I) (hereinafter sometimes referred to as "structural unit (I)"), a structural unit having a group represented by formula (II-x) (hereinafter sometimes referred to as "structural unit (II)"), and a structural unit having an acid labile group (hereinafter sometimes referred to as "structural unit (a1)"). It is preferable that the resist composition of the present invention further contains a resin other than the resin (A) (hereinafter, may be referred to as "resin (X)"), an acid generator (hereinafter, may be referred to as "acid generator (B)"), a quencher (hereinafter, may be referred to as "quencher (C)") and / or a solvent (hereinafter, may be referred to as "solvent (E)").

[0010] <Resin (A)> Resin (A) is a resin containing structural units (I), (II) and (a1). Resin (A) may contain structural units other than structural units (I), (II) and (a1) known in the art (hereinafter sometimes referred to as "structural units (s)").

[0011] (Structural unit (I)) The structural unit (I) is a structural unit represented by the following formula (I), and is derived from, for example, a salt represented by the following formula (Is) (hereinafter, sometimes referred to as salt (Is)) that can function as an acid generator. 2 =CR 10 The double bond is cleaved. In a salt (Is), the negatively charged side is sometimes called the "anion (Ia)" and the positively charged side is sometimes called the "cation (Ic)". TIFF2025081260000013.tif52151 [In formula (I) and formula (Is), all symbols have the same meanings as defined above.]

[0012] Q 1 , Q 2 , R 21 and R 22Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, and the like. Q 1 , Q 2 , R 21 and R 22 Examples of the alkyl group of Q 1 and Q 2 are preferably, in at least one of them, a fluorine atom or a perfluoroalkyl group, more preferably at least one of them is a fluorine atom or a perfluoroalkyl group, still more preferably each is independently preferably a trifluoromethyl group or a fluorine atom, and even more preferably both are fluorine atoms. R 21 and R 22 are each independently preferably a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, more preferably a hydrogen atom or a fluorine atom, and still more preferably a hydrogen atom. z is preferably any integer from 0 to 4, more preferably any integer from 0 to 3, still more preferably any integer from 0 to 2, and even more preferably 0 or 1. X 1 is preferably *-CO-O-, *-O-CO- or *-O-CO-O- (* represents the bonding site with C(R 21 )(R 22 )) or C(Q 1 )(Q 2 ))), and more preferably *-CO-O- or *-O-CO-. ).

[0013] R10 Examples of the halogen atom of 10 include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. R 10 Examples of the alkyl group of R include, within the range of 1 to 6 carbon atoms, a group the same as Q 1 and Q 2 and Q R 10 The alkyl group having 1 to 6 carbon atoms and a halogen atom of R includes an alkyl fluoride group having 1 to 6 carbon atoms, an alkyl chloride group having 1 to 6 carbon atoms, an alkyl bromide group having 1 to 6 carbon atoms, an alkyl iodide group having 1 to 6 carbon atoms, etc. Specifically, 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 perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a perchloromethyl group, a perbromomethyl group, and a periodomethyl group, etc. The number of carbon atoms of the alkyl group, alkyl fluoride group, alkyl chloride group, alkyl bromide group, and alkyl iodide group is preferably 1 to 4, more preferably 1 to 3, and still more preferably 1 or 2. R 10 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 or a methyl group, and even more preferably a methyl group. R 3 Examples of the alkyl group of R include the same groups as the alkyl group of R 10 and R X 10 When X is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025081260000014.tif3449[In formula (X10), Ax represents the bonding species that binds to the carbon atom to which R 10 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 L10 or X 1 represents a bonding species that combines with, 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, 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, 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 3 -. 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 the bonding position of Ax, and more preferably the p-position. X 10 Examples of [X 10 -1) to formula (X 10 -10). * represents the bonding site with the carbon atom to which -R 10 is bonded. TIFF2025081260000015.tif45170 [In formula (X 10 -1) to formula (X 10 -10), all symbols represent the same meaning as above. Specific examples of the group represented by formula (X 10 -1) to formula (X 10 -10) include the following groups. TIFF2025081260000016.tif87163 Among them, X 10 is a single bond or formula (X 10-1') and formula (X 10 -3') to formula (X 10 -10') is preferably a group represented by any of them, a single bond or formula (X 10 -1'), formula (X 10 -4'), formula (X 10 -5'), formula (X 10 -6') and formula (X 10 -10') is more preferably a group represented by any of them, 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') is even more preferred.

[0014] L 10 As the hydrocarbon group having 1 to 36 carbon atoms of L, an aliphatic hydrocarbon group (a linear or branched chain hydrocarbon group such as an alkanediyl group, an alkenediyl group, an alkynediyl group, and a monocyclic or polycyclic alicyclic hydrocarbon group), an aromatic hydrocarbon group, etc. may be mentioned, and a hydrocarbon group in which two or more of these groups are combined may also be used. 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; Branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group may be mentioned. The terminal of the branched alkanediyl group may be an alkyl group such as a methyl group. Examples of the alkenediyl group include an ethenediyl group, a propenediyl group, an isopropenediyl group, a butenediyl group, an isobutenediyl group, a tert-butenediyl group, a pentenediyl group, a hexenediyl group, a heptenediyl group, an octenediyl group, an isooctenediyl group, and a nonenediyl group. Examples of the alkynediyl group include an ethynediyl group, a propynediyl group, an isopropynediyl group, a butynediyl group, an isobutynediyl group, a tert-butynediyl group, a pentynediyl group, a hexynediyl group, an octynediyl group, a nonynediyl group, and the like. The number of carbon atoms in the chain hydrocarbon group may be 1 to 24, preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alicyclic hydrocarbon group may be monocyclic, polycyclic, or spirocyclic. Examples of the alicyclic hydrocarbon group include the groups represented below. The bonding site can be at any position. TIFF2025081260000017.tif47168Specifically, examples of the monocyclic divalent alicyclic hydrocarbon group include monocyclic cycloalkanediyl groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclohexene-3,6-diyl group, and a cyclooctane-1,5-diyl group. Examples of the polycyclic divalent alicyclic hydrocarbon group include polycyclic cycloalkanediyl groups such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, a 5-norbornene-2,3-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, a spirocyclohexane-1,2'-cyclopentane-diyl group, and a spiroadamantane-2,3'-cyclopentane-diyl group, and polycyclic alicyclic hydrocarbon groups such as a spiro ring having a cycloalkanediyl group spiro-bonded to each of a norbornanediyl group or an adamantanediyl group. The number of carbon atoms in the alicyclic hydrocarbon group may be 3 to 24, preferably 3 to 18, more preferably 3 to 16, and still more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, and the like. The number of carbon atoms in the aromatic hydrocarbon group may be 6 to 24, preferably 6 to 18, more preferably 6 to 14, and still more preferably 6 to 10. Examples of the hydrocarbon group formed by combining two or more types thereof include a group formed by combining an alkanediyl group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group, such as -alicyclic hydrocarbon group-alkandiyl group-, -alkandiyl group-alicyclic hydrocarbon group-, -alkandiyl group-alicyclic hydrocarbon group-alkandiyl group-, -alkandiyl group-aromatic hydrocarbon group-, -aromatic hydrocarbon group-alkandiyl group-, and the like. In the case of a group formed by combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with an alkanediyl group, the terminal of the alkanediyl group may be an alkyl group such as a methyl group.

[0015] L 10 in the hydrocarbon group having 1 to 36 carbon atoms of 2 -CH 2 - may be replaced by -O-, -S-, -CO- or -SO L 10 When the hydrocarbon group having 1 to 36 carbon atoms of 2 has a substituent or -CH 2 - in the hydrocarbon group is replaced by -O-, -S-, -CO- or -SO - the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group. Examples of the group in which -CH 2 - in the hydrocarbon group is replaced by -O-, -S-, -SO 2 - or -CO- include a hydroxy group (a group in which -CH 2 - in a methyl group is replaced by -O-), a carboxy group (a group in which -CH 2 -CH 2 - in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH 2- is a group replaced by -O-, an alkoxycarbonyl group (any -CH at an arbitrary position in the alkyl group) 2 -CH 2 - is a group replaced by -O-CO-, an alkylsulfonyl group (any -CH at an arbitrary position in the alkyl group) 2 - is 2 - replaced by -SO 2 - is a group replaced by -CO-, an alkylcarbonyl group (any -CH at an arbitrary position in the alkyl group) 2 -CH 2 - is a group replaced by -CO-O-, an alkoxycarbonyloxy group (any -CH at an arbitrary position in the alkyl group) 2 -CH 2 -CH 2 - is a group replaced by -O-CO-O-, an alkanediyl-oxy group (any -CH at an arbitrary position in the alkanediyl group) 2 - is a group replaced by -O-, an alkanediyl-oxycarbonyl group (any -CH at an arbitrary position in the alkanediyl group) 2 -CH 2 - is a group replaced by -O-CO-, an alkanediyl-carbonyl group (any -CH at an arbitrary position in the alkanediyl group) 2 - is a group replaced by -CO-, an alkanediyl-carbonyl-oxy group (any -CH at an arbitrary position in the alkanediyl group) 2 -CH 2 - is a group replaced by -CO-O-, an alkanediyl-sulfonyl group (any -CH at an arbitrary position in the alkanediyl group) 2 - is 2 - replaced by -SO 2 - is a group replaced by -S-, an alkylthio group (any -CH at an arbitrary position in the alkyl group) 2 - is a group replaced by -O-, an oxy group (any -CH in the methylene group) 2 - is a group replaced by -CO-, a carbonyl group (any -CH in the methylene group) 2- is a group replaced by -S-, a sulfonyl group (-CH contained in a methylene group) 2 - is -SO 2 - is a group replaced by -; an alkanediylthio group (-CH at any position contained in an alkanediyl group) 2 - is a group replaced by -S-, a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a group formed by combining two or more of these groups, and the like can be mentioned.

[0016] Examples of the alkoxy group include alkoxy groups having 1 to 35 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, and the like. The number of carbon atoms of the alkoxy group is preferably 1 to 17, more preferably 1 to 11, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 35 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 36 carbon atoms, such as acetyl group, propionyl group and butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 35 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 34 carbon atoms, such as butoxycarbonyloxy group. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 17, more preferably 2 to 11, still more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 18, more preferably 2 to 12, still more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 17, more preferably 2 to 11, still more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkoxycarbonyloxy group may be 2 to 16, preferably 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 35 carbon atoms, such as methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, butylsulfonyl group, pentylsulfonyl group, hexylsulfonyl group, octylsulfonyl group, 2-ethylhexylsulfonyl group, nonylsulfonyl group, decylsulfonyl group, undecylsulfonyl group and the like. The number of carbon atoms of the alkylsulfonyl group is preferably 1 to 17, more preferably 1 to 11, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-oxy group include alkanediyl-oxy groups having 1 to 35 carbon atoms, such as a methylene-oxy group, an ethylene-oxy group, a propanediyl-oxy group, a butanediyl-oxy group, and a pentanediyl-oxy group. The number of carbon atoms of the alkanediyl-oxy group is preferably 1 to 17, more preferably 1 to 11, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-oxycarbonyl group include alkanediyl-oxycarbonyl groups having 2 to 35 carbon atoms, such as a methylene-oxycarbonyl group, an ethylene-oxycarbonyl group, a propanediyl-oxycarbonyl group, and a butanediyl-oxycarbonyl group. Examples of the alkanediyl-carbonyl group include alkanediyl-carbonyl groups having 2 to 36 carbon atoms, such as a methylene-carbonyl group, an ethylene-carbonyl group, a propanediyl-carbonyl group, a butanediyl-carbonyl group, and a pentanediyl-carbonyl group. Examples of the alkanediyl-carbonyl-oxy group include alkanediyl-carbonyl-oxy groups having 2 to 35 carbon atoms, such as a methylene-carbonyl-oxy group, an ethylene-carbonyl-oxy group, a propanediyl-carbonyl-oxy group, and a butanediyl-carbonyl-oxy group. The number of carbon atoms of the alkanediyl-oxycarbonyl group is preferably 2 to 17, more preferably 2 to 11, still more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkanediyl-carbonyl group is preferably 2 to 18, more preferably 2 to 12, still more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkanediyl-carbonyl-oxy group is preferably 2 to 17, more preferably 2 to 11, still more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkylthio group include alkylthio groups having 1 to 35 carbon atoms, such as methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, 2-ethylhexylthio group, nonylthio group, decylthio group, undecylthio group and the like. The number of carbon atoms of the alkylthio group is preferably 1 to 17, more preferably 1 to 11, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylsulfonyl group include alkanediylsulfonyl groups having 1 to 35 carbon atoms, such as methylenesulfonyl group, ethylenesulfonyl group, propylenesulfonyl group and the like. The number of carbon atoms of the alkanediylsulfonyl group is preferably 1 to 17, more preferably 1 to 11, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylthio group include alkanediylthio groups having 1 to 35 carbon atoms, such as methylenethio group, ethylenethio group, propylenethio group and the like. The number of carbon atoms of the alkanediylthio group is preferably 1 to 17, more preferably 1 to 11, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the cycloalkoxy group include cycloalkoxy groups having 3 to 35 carbon atoms, such as cyclohexyloxy group and the like. Examples of the cycloalkylalkoxy group include cycloalkylalkoxy groups having 4 to 35 carbon atoms, such as cyclohexylmethoxy group and the like. Examples of the aromatic hydrocarbon group-carbonyloxy group include aromatic hydrocarbon group-carbonyloxy groups having 7 to 35 carbon atoms, such as benzoyloxy group and the like. Examples of the aromatic hydrocarbon group-carbonyl group include aromatic hydrocarbon group-carbonyl groups having 7 to 36 carbon atoms, such as benzoyl group and the like. Examples of the aromatic hydrocarbon group-oxy group include aromatic hydrocarbon group-oxy groups having 6 to 35 carbon atoms, such as phenyloxy group and the like. In addition, -CH contained in the alicyclic hydrocarbon group 2- is, -O-, -S-, -CO- or -SO 2 Examples of the group replaced by - include groups represented below and the like. -O- or -CO- in the groups represented below may be replaced by -S- or -SO 2 -. The bonding site can be at any position. TIFF2025081260000018.tif45168

[0017] L 10 Examples of the substituent that the hydrocarbon group of L may have include a halogen atom, a cyano group, and a nitro group. L 10 When L contains a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can be substantially regarded as a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. L 10 In the hydrocarbon group of L, -CH 2 - is replaced by a group such as -O- or -CO-, and L 10 can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, and an alkylsulfonyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L 10 The hydrocarbon group having 1 to 36 carbon atoms of L may have one substituent or a plurality of substituents.

[0018] L 10 is a single bond, a chain hydrocarbon group having 1 to 18 carbon atoms which may have a substituent (however, -CH 2 - in the chain hydrocarbon group may be replaced by -O- or -CO-), or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (however, -CH 2 - in the cyclic hydrocarbon group is -O-, -S-, -CO- or -SO 2- may be replaced therewith.) or a group formed by combining a linear hydrocarbon group having 1 to 16 carbon atoms which may have a substituent and a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (however, -CH contained in the linear hydrocarbon group 2 - may be replaced with -O- or -CO-, and -CH contained in the cyclic hydrocarbon group 2 - may be replaced with -O-, -S-, -SO 2 - or -CO-. It is preferably a single bond, a linear hydrocarbon group having 1 to 10 carbon atoms which may have a substituent (however, -CH contained in the linear hydrocarbon group 2 - may be replaced with -O- or -CO-), a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (however, -CH contained in the cyclic hydrocarbon group 2 - may be replaced with -O-, -S-, -CO- or -SO 2 -. It is more preferably a single bond, a linear hydrocarbon group having 1 to 8 carbon atoms which may have a substituent and a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (however, -CH contained in the linear hydrocarbon group 2 - may be replaced with -O- or -CO-, and -CH contained in the cyclic hydrocarbon group 2 - may be replaced with -O-, -S-, -SO 2 - or -CO-. It is even more preferably a single bond, an alkanediyl group having 1 to 6 carbon atoms which may have a substituent (however, -CH contained in the alkanediyl group 2 - may be replaced with -O- or -CO-), a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (however, -CH contained in the cyclic hydrocarbon group 2 - may be replaced with -O-, -S-, -SO 2 - or -CO-), or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms and a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (however, -CH contained in the alkanediyl group 2 - may be replaced with -O- or -CO-, and -CH contained in the cyclic hydrocarbon group 2 - may be replaced with -O-, -S-, -SO 2-or may be replaced by -CO-. It is more preferable that it is, a single bond, an alkanediyl group having 1 to 4 carbon atoms which may have a substituent (provided that -CH contained in the alkanediyl group 2 -may be replaced by -O- or -CO-.), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (provided that -CH contained in the alicyclic hydrocarbon group 2 -may be replaced by -O-, -S-, -SO 2 -or -CO-.), an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (provided that -CH contained in the alkanediyl group 2 -may be replaced by -O- or -CO-, and -CH contained in the alicyclic hydrocarbon group 2 -may be replaced by -O-, -S-, -SO 2 -or -CO-.), or a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent (provided that -CH contained in the alkanediyl group 2 -may be replaced by -O- or -CO-. It is even more preferable that it is, a single bond, an alkanediyl group having 1 to 4 carbon atoms which may have a substituent (provided that -CH contained in the alkanediyl group 2 -may be replaced by -O- or -CO-.), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (provided that -CH contained in the alicyclic hydrocarbon group 2 -may be replaced by -O- or -CO-.), a phenylene group which may have a substituent, a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (provided that -CH contained in the alkanediyl group 2 -may be replaced by -O- or -CO-, and -CH contained in the alicyclic hydrocarbon group 2- may be replaced by -O- or -CO-. ) or a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and a phenylene group which may have a substituent (provided that -CH contained in the alkanediyl group 2 - may be replaced by -O- or -CO-. ) is more preferably, a single bond, an alkanediyl group having 1 to 4 carbon atoms (provided that -CH contained in the alkanediyl group 2 - may be replaced by -O- or -CO-. ) or a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and a phenylene group which may have a substituent (provided that -CH contained in the alkanediyl group 2 - may be replaced by -O- or -CO-. ) is even more preferably.

[0019] Examples of the anion (I-a) include the following anions. TIFF2025081260000019.tif231166

[0020] TIFF2025081260000020.tif128148

[0021] In the anions represented by formula (I-a-1) to formula (I-a-38), an anion in which the methyl group corresponding to R in formula (I) 10 is replaced by a hydrogen atom can also be cited as a specific example of the anion (I-a). Among them, the anions represented by formula (I-a-1) to formula (I-a-6), formula (I-a-10) to formula (I-a-12), and formula (I-a-16) to formula (I-a-32) are preferred.

[0022] Z1 +Examples of the organic cation include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations or aryliodonium cations are more preferred. Specifically, cations represented by any of formula (b2-1) to formula (b2-5) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number) are included. TIFF2025081260000021.tif84161[In formula (b2-1) to formula (b2-5), R b4 ~R b6 each independently represents a linear hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the linear hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 and may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH 2 - contained in the ring may be replaced with -O-, -S-, or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of any of 0 to 5. When m2 is 2 or more, a plurality of Rs b7 may be the same or different, and when n2 is 2 or more, a plurality of Rs b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and the -CH 2 - contained in the ring may be replaced by -O-, -S- or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the chain hydrocarbon group may be substituted by an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted by an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including -CH-CO- to which they are bonded, and the -CH 2 - contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 and R b21 ~R b26 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. R b13 and R b14 and R b21 and R b22 may be bonded to each other to form a ring containing a sulfur atom together with the benzene ring to which they are bonded, and the -CH2 - 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 from 0 to 5. q2 and r2 each independently represent an integer from 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, the plurality of R b13 are the same or different, when p2 is 2 or more, the plurality of R b14 are the same or different, when q2 is 2 or more, the plurality of R b15 are the same or different, when r2 is 2 or more, the plurality of R b16 are the same or different, when s2 is 2 or more, the plurality of R b17 are the same or different, when t2 is 2 or more, the plurality of R b18 are the same or different. u3 represents an integer from 1 to 3 and satisfies 1 ≦ u3 + q23 ≦ 5. u4 and u5 each independently represent an integer from 0 to 3 and satisfy 0 ≦ u4 + o21 ≦ 5 and 0 ≦ u5 + p22 ≦ 5. When u3, u4, and u5 are each 2 or more, the groups within the plurality of parentheses are each the same or different. o21, p22, q23, r24, t25, and s26 each independently represent an integer from 0 to 4. 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 u2 is 0, any one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16At least one of them is preferably a halogen atom. When u2 is 1, any one of o2, p2, s2, t2, q2 and r2 is 1 or more, and R b13 ~R b18 At least one of them is preferably a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, and more preferably 1. Also, when u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom.

[0023] The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. In particular, the chain hydrocarbon group of R b9 ~R b12 is preferably having 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups and the like. TIFF2025081260000022.tif11157 In particular, the alicyclic hydrocarbon group of R b9 ~R b12 is preferably having 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

[0024] 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.

[0025] 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.

[0026] 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 a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.

[0027] Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, a dodecyloxy group, and the like. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, a 2-ethylhexylcarbonyloxy group, and the like.

[0028] R b4 and R b5 The ring formed by R and R being bonded to each other together with the sulfur atom to which they are bonded may be any of a monocyclic, polycyclic, aromatic, non-aromatic, saturated, and unsaturated ring. Examples of this ring include rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. Further, examples of the ring containing a sulfur atom include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, the following rings can be mentioned. * represents a bonding site. TIFF2025081260000023.tif18125

[0029] R b9 and R b10 The ring formed by R and R together may be any of a monocyclic, polycyclic, aromatic, non-aromatic, saturated, and unsaturated ring. Examples of this ring include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, a 1,4-oxathian-4-ium ring, and the like can be mentioned. R b11 and R b12The ring formed together with the following may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring, etc. R b27 ~R b29 Examples of the group containing an acid-labile group of ~R c30 include -R c30 or -L c10 -CO-O-R c30 wherein the group represented by (L c10 represents an alkanediyl group having 1 to 6 carbon atoms, and R c30 represents an acid-labile group.). etc. are included. R b27 ~R b29 The acid-labile group of ~R is preferably a group represented by formula (1) described later and / or a group represented by formula (2).

[0030] Among cations (b2-1) to (b2-5), preferably, it is cation (b2-1), cation (b2-4) or cation (b2-5). Examples of cation (b2-1) include the following cations. TIFF2025081260000024.tif158165 Examples of cation (b2-2) include the following cations. TIFF2025081260000025.tif14136 Examples of cation (b2-3) include the following cations. TIFF2025081260000026.tif21130 Examples of cation (b2-4) include the following cations. TIFF2025081260000027.tif122163 Examples of cation (b2-5) include the following cations. TIFF2025081260000028.tif115158

[0031] Salt (I-s) is the above-mentioned anion (I-a) and the above-mentioned organic cation Z1+ (Cation (I-c)), and these can be arbitrarily combined. As the salt (I-s), preferably, an anion represented by any of the formulas (I-a-1) to (I-a-6) and a combination with cation (b2-1), cation (b2-2), cation (b2-3), cation (b2-4), or cation (b2-5) are exemplified.

[0032] Examples of the salt (I-s) include the salts described in Table 1. In the following table, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation, and "~" indicates that each of the salt (I-s), anion (I), and cation (I) corresponds. For example, the salt (I-s-1) means a salt composed of an anion represented by the formula (I-a-1) and a cation represented by the formula (b2-c-1), and represents the salts shown below. TIFF2025081260000029.tif2795

Table 1

[0033] 〈Structural unit (II)〉 The structural unit (II) is a structural unit having a group represented by formula (II-x), and preferably a structural unit having a group represented by formula (II-x) in the side chain. TIFF2025081260000032.tif2958 [In formula (II-x), all symbols have the same meaning as described above.]

[0034] Ring W 1 represents a ring structure in which, as an atom constituting the ring, it contains a nitrogen atom, and one of the carbon atoms constituting the ring forms a carbonyl group together with an oxo group (=O). Ring W 1 The heterocyclic ring of Ring W, for example, -CH 2 - constituting the ring may be further replaced by -O-, -S-, -CO- or -NR c -, etc. R c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. The heterocyclic ring of Ring W 1 may be an aromatic heterocyclic ring or an alicyclic heterocyclic ring having no aromaticity. Also, it may be either monocyclic or polycyclic.

[0035] The following formula As the group represented by TIFF2025081260000033.tif in 1923, specifically, the following can be mentioned. * represents the bonding site with the carbon atom of the carbonyl group. TIFF2025081260000034.tif 130162

[0036] Ring W 1 The hydrogen atoms contained in the heterocyclic ring having 2 to 36 carbon atoms represented by may be a halogen atom or a hydrocarbon group having 1 to 24 carbon atoms (the -CH contained in the hydrocarbon group 2 - may be replaced by an -O-, -S-, -CO- or -NR c - group). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. Examples of the hydrocarbon group include an aliphatic hydrocarbon group, an aromatic hydrocarbon group and a group combining these. The -CH contained in the hydrocarbon group 2 - may be replaced by an -O-, -S-, -CO-, -NR c - group (R c represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), and is preferably replaced by -O- or -CO-. The aliphatic hydrocarbon group represents a chain hydrocarbon group, an alicyclic hydrocarbon group, and a group combining a chain hydrocarbon group and an alicyclic hydrocarbon group. The chain hydrocarbon group may be saturated or unsaturated, and may be linear or branched. For example, linear saturated alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group, pentadecyl group and hexadecyl group; branched saturated alkyl groups such as isopropyl group, sec-butyl group, tert-butyl group and 2-ethylhexyl group; linear unsaturated alkyl groups such as vinyl group, propenyl group, hexenyl group and octenyl group; and branched unsaturated alkyl groups such as 3-methyl-2-butenyl group. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 12, more preferably 1 to 10, still more preferably 1 to 8, even more preferably 1 to 6, and even more preferably 1 to 4. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include monocyclic cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include polycyclic cycloalkyl groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, a methylnorbornyl group, and groups as described below. TIFF2025081260000035.tif9159 The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the group formed by combining a chain hydrocarbon group and an alicyclic hydrocarbon group include a group formed by bonding the above chain hydrocarbon group and the above alicyclic hydrocarbon group, a group formed by bonding the above alicyclic hydrocarbon group and the above chain hydrocarbon group, and a group formed by bonding the above chain hydrocarbon group, the above alicyclic hydrocarbon group, and the above chain hydrocarbon group, within the range allowed by the upper limit of the number of carbon atoms. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and an anthryl group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and even more preferably 6 to 10. Examples of the group formed by combining an aliphatic hydrocarbon group and an aromatic hydrocarbon group include, within the range allowed by the upper limit of the number of carbon atoms, for example, a group formed by bonding the above chain hydrocarbon group and the above aromatic hydrocarbon group, a group formed by bonding the above aromatic hydrocarbon group and the above chain hydrocarbon group, and a group formed by bonding the above aromatic hydrocarbon group and the above alicyclic hydrocarbon group directly or via the above chain hydrocarbon group. -CH 2 - in the hydrocarbon group is replaced by -O-, -S-, -CO- or -NR c - Examples of the resulting group include a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkylthio group, an amino group, a thiol group, an alkoxycarbonyl group, an alkylsulfonyl group, and an alkylamino 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. The number of carbon atoms in the alkoxy group is from 1 to 12, preferably from 1 to 8, more preferably from 1 to 6, still more preferably from 1 to 4, and even more preferably from 1 to 3. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is from 2 to 12, preferably from 2 to 8, more preferably from 2 to 6, still more preferably from 2 to 4, and even more preferably from 2 to 3. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, and an isobutyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is from 2 to 12, preferably from 2 to 8, more preferably from 2 to 6, still more preferably from 2 to 4, and even more preferably from 2 to 3. Examples of the alkylthio group include a methylthio group, an ethylthio group, a propylthio group, and a butylthio group. The number of carbon atoms in the alkylthio group is from 1 to 12, preferably from 1 to 8, more preferably from 1 to 6, still more preferably from 1 to 4, and even more preferably from 1 to 3. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. The number of carbon atoms in the alkoxycarbonyl group is from 2 to 12, preferably from 2 to 8, more preferably from 2 to 6, still more preferably from 2 to 4, and even more preferably from 2 to 3. Examples of the alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, a butylsulfonyl group, a pentylsulfonyl group, a hexylsulfonyl group, an octylsulfonyl group, a nonylsulfonyl group, a decylsulfonyl group, an undecylsulfonyl group, and the like. The number of carbon atoms in the alkylsulfonyl group is preferably from 1 to 12, more preferably from 1 to 8, still more preferably from 1 to 6, even more preferably from 1 to 4, and even more preferably from 1 to 3. Examples of the alkylamino group include a methylamino group, an ethylamino group, a propylamino group, a butylamino group, and the like. The number of carbon atoms in the alkylamino group is preferably from 1 to 12, more preferably from 1 to 8, still more preferably from 1 to 6, even more preferably from 1 to 4, and even more preferably from 1 to 3.

[0037] Ring W 1 is preferably a 4- to 12-membered heterocyclic ring containing a nitrogen atom or a heterocyclic ring containing the 4- to 12-membered ring, more preferably a 4- to 7-membered heterocyclic ring containing a nitrogen atom or a heterocyclic ring containing the 4- to 7-membered ring, still more preferably a 4- to 6-membered heterocyclic ring containing a nitrogen atom or a heterocyclic ring containing the 4- to 6-membered ring, and even more preferably a 4- to 6-membered heterocyclic ring containing a nitrogen atom or a polycyclic structure containing the 4- to 6-membered heterocyclic ring. -CO- is located at a position adjacent to the nitrogen atom, that is, Ring W 1 is preferably a lactam ring, and more preferably a lactam ring having a polycyclic structure. Ring W 1 When a hydrogen atom contained in the heterocyclic ring of Ring W is replaced with a halogen atom, a hydrocarbon group, or the like, it is preferably replaced with a halogen atom, a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or an alkylcarbonyloxy group having 2 to 4 carbon atoms, and more preferably replaced with an iodine atom, a fluorine atom, a hydroxy group, an alkylcarbonyl group having 2 to 4 carbon atoms, or an alkylcarbonyloxy group having 2 to 4 carbon atoms.

[0038] The structural unit having a group represented by the formula (II-x) has a group derived from a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, and a methacryloylthio group. Among them, the monomer that leads to the structural unit (II) is preferably a monomer having an ethylenically unsaturated bond, and more preferably a (meth)acrylic monomer.

[0039] The structural unit (II) is preferably a structural unit represented by the formula (IIA). TIFF2025081260000036.tif4056[In the formula (IIA), all the symbols have the same meanings as described above.]

[0040] R x Examples of the halogen atom of R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R x Examples of the alkyl group of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group. Preferably, it is an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group. R x Examples of the alkyl group having a halogen atom of R include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. R x 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.

[0041] A X1Examples of the divalent saturated hydrocarbon group include chain saturated hydrocarbon groups such as linear or branched alkanediyl groups, and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups. A combination of two or more of these groups may also be used. 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, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1,17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group, and 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, and 2-methylbutane-1,4-diyl group; Monocyclic divalent alicyclic saturated hydrocarbon groups which are monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; Polycyclic divalent alicyclic saturated hydrocarbon groups which are polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group, etc. The number of carbon atoms of the chain saturated hydrocarbon group is preferably 1 to 12, more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. The number of carbon atoms of the alicyclic saturated hydrocarbon group is preferably 3 to 16, more preferably 3 to 12, and still more preferably 3 to 10. -CH 2 - in the saturated hydrocarbon group is -O-, -CO-, or -NR d-As the group replaced, there are a hydroxy group, a carboxy group, an amino group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkylamino group, an oxy group, a carbonyl group, an alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyl-oxy group, an alkanediylamino group, and -CH contained in an alicyclic saturated hydrocarbon group 2 -is replaced by -O-, -CO- or -NR d -; a group formed by combining two or more of these groups; and the like. These replaced groups include the same groups as those exemplified in this specification, within the range where the upper limit of the number of carbon atoms permits. A X1 is an alkanediyl group having 1 to 6 carbon atoms (the -CH contained in the alkanediyl group 2 -may be replaced by -O-, -CO- or -N(R d ))-. It is preferably an alkanediyl group having 1 to 4 carbon atoms (the -CH contained in the alkanediyl group 2 -may be replaced by -O-, -CO- or -N(R d ))-. It is more preferably such an alkanediyl group. A X is preferably a single bond, -CO-O-(CH 2 )gg-*,-CO-NH-(CH 2 )gg-*,-CO-O-(CH 2 )gg-O-*(*represents the bonding site with the carbonyl group. gg represents an integer of 1 to 4). More preferably, it is a single bond, -CO-O-(CH 2 )gg-*(*represents the bonding site with the carbonyl group. gg represents an integer of 1 to 4). Even more preferably, it is a single bond.

[0042] Examples of the structural unit (II) include the following structural units. TIFF2025081260000037.tif42163

[0043] In the structural units represented by Formulas (II-1) to (II-10) of TIFF2025081260000038, R X Structural units in which the methyl group corresponding to X is replaced by a hydrogen atom can also be cited as specific examples of the structural unit (II). Among them, the structural units represented by Formula (II-1) and Formulas (II-6) to (II-9) are preferred, and the structural units represented by Formula (II-1) and Formula (II-7) are more preferred.

[0044] The resin (A) may contain two or more structural units (II). The total content ratio of the structural unit (II) in the resin (A) is 0.1 mol% or more, preferably 0.5 mol% or more, more preferably 0.8 mol% or more, still more preferably 1 mol% or more, even more preferably 3 mol% or more, still even more preferably 5 mol% or more, and yet even more preferably 7 mol% or more, based on all the structural units of the resin (A). Also, it is 60 mol% or less, preferably 50 mol% or less, more preferably 40 mol% or less, still more preferably 30 mol% or less, even more preferably 25 mol% or less, still even more preferably 20 mol% or less, and yet even more preferably 15 mol% or less. Specifically, it is 1 to 60 mol%, preferably 1 to 50 mol%, more preferably 1 to 40 mol%, still more preferably 1 to 30 mol%, even more preferably 3 to 25 mol%, still even more preferably 3 to 20 mol%, and yet even more preferably 5 to 15 mol%. The total content ratio of these structural units is the same also in the structural unit represented by Formula (IIA).

[0045] <Structural unit (a1): Structural unit having an acid-labile group> In addition to the structural unit represented by Formula (I) and the structural unit represented by Formula (II), the resin (A) further contains a 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) 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)). TIFF2025081260000039.tif2298[In the formula (1), R a1 、R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a 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.] TIFF2025081260000040.tif2278[In the formula (2), R a1’ and R a2’ each independently represents 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 the -CH 2 - 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.]

[0046] Examples of the alkyl group for R a1 、R a2 and R a3 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and the like. R a1 、R a2 and R a3 Examples of the alkenyl group for R R a1 、R a2 and R a3 The alicyclic hydrocarbon group for R a1 、R a2 and R a3 may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents the bonding site). The number of carbon atoms of the alicyclic hydrocarbon group for R TIFF2025081260000041.tif10159R a1 、R a2 and R a3 Examples of the aromatic hydrocarbon group for R Examples of the combined groups include groups combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group and the like), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group and the like), aryl-cycloalkyl groups such as phenylcyclohexyl group and the like. Preferably, ma is 0 and na is 1. R a1 and R a2 are bonded to each other to form an alicyclic hydrocarbon group, -C(R a1 )(R a2 )(R a3 ) includes the following groups. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents the bonding site to -O-. TIFF2025081260000042.tif27138

[0047] R a1’ 、R a2’ and R a3’ The hydrocarbon groups in may include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and the group formed by combining these are the same as the groups mentioned for R a1 、R a2 and R a3 . R a2’ and R a3’ are bonded to each other to form a heterocyclic group together with the carbon atom to which they are bonded and X, -C(R a1’ )(R a2’ )-X-R a3’ includes the following groups. * represents the bonding site. TIFF2025081260000043.tif19124R a1’ and R a2’ Preferably, at least one of them is a hydrogen atom. na’ is preferably 0. R a1 、R a2 、R a3 、R a1 、R a2’ and R a3’ The halogen atoms that may be included are fluorine atom, chlorine atom, bromine atom or iodine atom.

[0048] 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. As such a group, a tert-butoxycarbonyl group is preferable. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, R a3 is an alkyl group, ma = 0, and na = 1. In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1. Specific examples of the group (1) include the following groups. * represents the bonding site. TIFF2025081260000044.tif150162

[0049] Specific examples of the group (2) include the following groups. * represents the bonding site. TIFF2025081260000045.tif55153

[0050] 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 preferable. If a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0051] Examples of the structural unit derived from the (meth)acrylic monomer having the group (1) include a structural unit represented by formula (a1-0) (hereinafter, sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter, sometimes referred to as structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of 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. TIFF2025081260000046.tif44140 [In formula (a1-0), formula (a1-1) and formula (a1-2), all symbols have the same meaning as above.]

[0052] R a01 , R a4 and R a5 The halogen atom in the formula (I) includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a01 , R a4 and R a5 Examples 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 , Ra4 and R a5 is preferably a hydrogen atom or a methyl group, more preferably a methyl group. L a01 L a1 and L a2 is preferably an oxygen atom or *-O-(CH 2 ) k01 -CO-O- (wherein k01 is preferably any integer from 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 R a03 R a04 R a6 and R a7 Examples of the alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combinations thereof in R a1 R a2 and R a3 include the same groups as those exemplified for R R a02 R a03 and R a04 The alkyl group in R R a6 and R a7 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 R R a02 R a03 and R a04 R a6 and R a7 The number of carbon atoms of the alicyclic hydrocarbon group in R R a02 R a03 Ra04 , R a6 and R a7 The number of carbon atoms of the aromatic hydrocarbon group of R and R is preferably 6 to 12, more preferably 6 to 10. For the group combining an alkyl group and an alicyclic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and alicyclic hydrocarbon group is 18 or less. For the group combining an alkyl group and an aromatic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and aromatic hydrocarbon group is 18 or less. R a02 and R a03 are preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group which may have a halogen atom. R a04 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a halogen atom, 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 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.

[0053] Examples of the structural unit (a1-0) include a structural unit represented by any one of formulas (a1-0-1) to (a1-0-24) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-0) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Structural units represented by any one of formulas (a1-0-1) to (a1-0-10), formula (a1-0-13), formula (a1-0-14), and formulas (a1-0-19) to (a1-0-24) are preferred. a01 Examples of the structural unit (a1-1) include a structural unit derived from the monomers described in JP-A-2010-204646. Among them, a structural unit represented by any one of formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group are preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF2025081260000047.tif119160

[0054] Examples of the structural unit (a1-1) include a structural unit derived from the monomers described in JP-A-2010-204646. Among them, a structural unit represented by any one of formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group are preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. a4 Examples of the structural unit (a1-1) include a structural unit derived from the monomers described in JP-A-2010-204646. Among them, a structural unit represented by any one of formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group are preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. JPEG2025081260000048.jpg38168

[0055] Examples of the structural unit (a1-2) include a structural unit represented by any one of formulas (a1-2-1) to (a1-2-20) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Structural units represented by any one of formula (a1-2-2), formula (a1-2-5), formula (a1-2-6), and formulas (a1-2-10) to (a1-2-20) are preferred. a5 Examples of the structural unit (a1-2) include a structural unit represented by any one of formulas (a1-2-1) to (a1-2-20) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Structural units represented by any one of formula (a1-2-2), formula (a1-2-5), formula (a1-2-6), and formulas (a1-2-10) to (a1-2-20) are preferred. When the resin (A) contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin (A) contains the structural unit (a1-0), the content thereof is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, even more preferably 25 mol% or more, still even more preferably 30 mol% or more, and even more preferably 35 mol% or more, based on all the structural units of the resin (A). Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, and even more preferably 60 mol% or less. Specifically, it is 5 to 80 mol%, preferably 5 to 75 mol%, and more preferably 10 to 70 mol%. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, still more preferably 20 to 80 mol%, even more preferably 20 to 75 mol%, still even more preferably 20 to 70 mol%, and even more preferably 20 to 55 mol%.

[0056] Examples of the structural unit having the group (2) in the structural unit (a1) include a structural unit represented by the formula (a1-4) (hereinafter, may be referred to as "structural unit (a1-4)"). TIFF2025081260000050.tif31119[In the formula (a1-4), all the symbols have the same meanings as described above.]

[0057] R a1 and R a17 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R a01 are the same as those exemplified by R of the formula (a1-0). R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group. R a17Examples of the alkoxy group in [compound name] include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, and hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably an alkoxy group having 1 to 3 carbon atoms, still more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a17 Examples of the alkoxyalkyl group in [compound name] include methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably an alkoxyalkyl group having 2 to 4 carbon atoms, still more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a17 Examples of the alkoxyalkoxy group in [compound name] include methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, ethoxyethoxy group, propoxymethoxy group, isopropoxymethoxy group, butoxymethoxy group, sec-butoxymethoxy group, and tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably an alkoxyalkoxy group having 2 to 4 carbon atoms, still more preferably a methoxyethoxy group or an ethoxyethoxy group. R a17 Examples of the alkylcarbonyl group in [compound name] include acetyl group, propionyl group, and butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 4 carbon atoms, more preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and still more preferably an acetyl group. R a17 Examples of the alkylcarbonyloxy group in [compound name] include acetyloxy group, propionyloxy group, and butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 4 carbon atoms, more preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and still more preferably an acetyloxy group. Ra17 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group.

[0058] A a11 Examples of the alkanediyl group of include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, undecane-1,10-diyl group, etc. The number of carbon atoms of the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, still more preferably 1 to 4, yet even more preferably 1 to 3, and even more preferably 1 or 2. R a18 Examples of the alkyl group of include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group. A a11 When -CH 2 - contained in the alkanediyl group of is replaced by -O-, -CO- or -NR a18 -, the number of carbon atoms before replacement is taken as the number of carbon atoms of the alkanediyl group. A a11 -CH contained in the alkanediyl group of2 - is a group replaced by -O-, -CO- or -NR a18 - The groups replaced are hydroxy group, carboxy group, carbonyl group, oxy group, amino group (the -CH contained in the methyl group 2 - is a group replaced by -NR a18 - group), alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylamino group (any -CH at any position contained in the alkyl group 2 - is a group replaced by -NR a18 - group), peptide group (the -CH contained in the ethylene group 2 -CH 2 - is a group replaced by -CO-NR a18 - group), alkanedioxy group, alkanedioxycarbonyl group, alkanediylcarbonyl group, alkanediylcarbonyloxy group, alkanediylsulfonyl group, alkanediylthio group, alkanediylamino group (any -CH at any position contained in the alkanediyl group 2 - is a group replaced by -NR a18 - group), etc. These replaced groups include those similar to those exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. 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, etc. The number of carbon atoms of the alkylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 11 carbon atoms, such as methyleneamino group, ethyleneamino group, propyleneamino group, etc. The number of carbon atoms of the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. For example, A a11 The -CH contained in the alkanediyl group of 2 - is -O-, -CO- or -NR a18-The groups replacing - include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a12 -CO-O-, *-O-CO-A a12 -O-, *-O-A a12 -CO-O-, *-CO-O-A a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 - are included. Among them, *-CO-O-, *-CO-O-A a12 -CO-O-, *-O-A a12 -CO-O-, *-CO-NR a18 - are preferred. Here, A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site with the carbon atom to which R a1 is bonded. The alkanediyl group of A a12 includes the same alkanediyl groups as A a11 within the range allowed by the upper limit of the number of carbon atoms. A a11 is preferably a single bond, *-CO-O- or *-CO-O-A a12 -CO-O-, more preferably a single bond, *-CO-O- or *-CO-O-CH 2 -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.

[0059] R a34 、R a35 and R a36 The hydrocarbon groups in include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these. Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, etc. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents the bonding site). Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like. Examples of the combined group include a group formed by combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group and the like), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group and the like), aryl-cycloalkyl groups such as phenylcyclohexyl group and the like. In particular, R a36 Examples 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. R a35 and R a36 Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms formed by R and R bonding to each other together with the -C-O- to which they are bonded include, for example, the following groups. * represents the bonding site, and one side is the bonding site with R a34 TIFF2025081260000052.tif15105

[0060] R a34 is preferably a hydrogen atom.​ R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a36 The hydrocarbon group of is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms. R a36 The alkyl group and the alicyclic hydrocarbon group in are preferably unsubstituted. R a36 The aromatic hydrocarbon group in preferably has an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0061] -O-C(R a34 )(R a35 )-O-R a36 in the structural unit (a1-4) dissociates 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, it may be bonded to any of the o-position, m-position or p-position with respect to the bonding position of A a11 . Among them, 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 1st 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.

[0062] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferably, the structural units represented by formulae (a1-4-1) to (a1-4-42) and the hydrogen atom corresponding to R in the structural unit (a1-4) a1 are replaced by a halogen atom, a haloalkyl group or an alkyl group. More preferably, the structural units represented by formulae (a1-4-1) to (a1-4-5), formula (a1-4-10), formula (a1-4-13), formula (a1-4-14), formula (a1-4-19), and formula (a1-4-20) are mentioned. When the resin (A) contains the structural unit (a1-4), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more with respect to the total of all the structural units of the resin (A). Also, 95 mol% or less is mentioned, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, even more preferably 20 to 70 mol%, and still even more preferably 20 to 60 mol%.

[0063] 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)"). TIFF2025081260000054.tif4558[In formula (a1-5), all the symbols have the same meanings as described above.]

[0064] Ra8 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in (a1) include R in the formula (a1-0). a01 Examples thereof include the same ones as those exemplified by the like of etc. In the formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Among them, it is preferable that one is -O- and the other is -S-. s1 is preferably 1. s1' is preferably any integer from 0 to 2. Z a1 is preferably a single bond or *-CH 2 -CO-O-.

[0065] Examples of the structural unit (a1-5) include, for example, structural units derived from monomers described in JP-A-2010-61117. Among them, the structural units represented by the formula (a1-5-1) to the formula (a1-5-4) are preferable, and the structural unit represented by the formula (a1-5-1) or the formula (a1-5-2) is more preferable. When the resin (A) contains the structural unit (a1-5), the content thereof is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, even more preferably 10 mol% or more, still even more preferably 20 mol% or more, and even more preferably 25 mol% or more, based on all the structural units of the resin (A). Also, 80 mol% or less, preferably 70 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 45 mol% or less, still even more preferably 40 mol% or less, and even more preferably 30 mol% or less can be mentioned. Specifically, 1 to 50 mol% is preferable, 3 to 45 mol% is more preferable, 5 to 40 mol% is still more preferable, and 5 to 30 mol% is even more preferable.

[0066] Examples of the structural unit having the group (1) in the structural unit (a1) include a structural unit represented by the formula (a1-6) (hereinafter sometimes referred to as "structural unit (a1-6)"). TIFF2025081260000056.tif3481[In the formula (a1-6), all the symbols have the same meanings as described above.]

[0067] R a61 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in include the same ones as exemplified for R in the formula (a1-0). a01 The like as those exemplified above can be mentioned. R a61 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. R a62 R a63 R a64 R a65 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group and the like. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and still more preferably a methyl group or an ethyl group. R a62 R a63 R a64 Examples of the cyclic hydrocarbon group in include an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group and the like. Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, a methacryloyloxy group, and the like. R a62 and R a63 Examples of the ring formed by R a62 and R a63 bonding to each other include an adamantane ring, a cyclopentane ring, a cyclohexane ring, and the like. Specifically, when R a62 and R a63 bond to each other to form a ring, examples of -C(R a64 )(R TIFF2025081260000057.tif32110

[0068] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in L L a61 and L a62 are preferably each independently a methylene group or an ethylene group. X a61 is preferably a single bond or -CO-O-*, and more preferably a single bond. X a62 is preferably a single bond or *-O-L a61 -, and more preferably a single bond. Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, 1-naphthylene group, 2-naphthylene group, 1-anthrylene group, 9-anthrylene group, biphenylene group, 1-phenanthrylene group, 2-phenanthrylene group, and the like. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, hydroxy group, alkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 12 carbon atoms, alkoxyalkoxy group having 2 to 12 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyloxy group having 2 to 4 carbon atoms, acryloyloxy group, or methacryloyloxy group. Examples of the halogen atom include a fluorine atom, iodine atom, chlorine atom, bromine atom, and the like. Examples of the alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group. The alkyl group preferably has 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of the alkoxy group include a methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, hexyloxy group. The alkoxy group preferably has 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, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, tert-butoxymethyl group. The alkoxyalkyl group preferably has 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, more preferably an acetyl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Preferred substituents include a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms. More preferred are a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group. Even more preferred are a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, more preferably a phenylene group which may have a hydroxy group.

[0069] Examples of the structural unit (a1-6) include structural units represented by Formula (a1-6-1) to Formula (a1-6-44). Structural units represented by Formula (a1-6-1) to Formula (a1-6-9) are preferred, structural units represented by Formula (a1-6-1), Formula (a1-6-2), Formula (a1-6-4), Formula (a1-6-5), Formula (a1-6-7), or Formula (a1-6-8) are more preferred, and structural units represented by Formula (a1-6-1) or Formula (a1-6-2) are even more preferred. In the following structural units, R a61A structural unit in which a hydrogen atom corresponding to is replaced with a methyl group or the like, and in the following structural unit, R a61 A structural unit in which a methyl group corresponding to a61 is replaced with a hydrogen atom or the like is also included as the structural unit (a1-6). TIFF2025081260000058.tif227164

[0070] When the resin (A) contains the structural unit (a1-6), the content is 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, still more preferably 10 mol% or more, even more preferably 20 mol% or more, still even more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on all the structural units of the resin (A). Also, 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 65 mol%.

[0071] Also, examples of the structural unit (a1) include the following structural units. TIFF2025081260000059.tif33167

[0072] When the resin (A) contains structural units represented by the formulas (a1-7-1) to (a1-7-7), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 95 mol% is preferable, 15 to 90 mol% is more preferable, 20 to 85 mol% is still more preferable, 20 to 70 mol% is even more preferable, and 20 to 60 mol% is particularly preferable.

[0073] Also, examples of the structural unit (a1) include the following structural units. TIFF2025081260000060.tif51120 When the resin (A) contains 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). 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.

[0074] 〈Structural unit (s)〉 The structural unit(s) is / are derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer(s)"). As the monomer from which the structural unit(s) is / are derived, a monomer having no acid-labile group known in the resist field can be used. The structural unit(s) preferably has 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 no acid-labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and no acid-labile group (hereinafter sometimes referred to as "structural unit (a3)") in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved. In addition to the above-described structural units, the structural unit(s) includes a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)". However, the structural unit represented by formula (I) is excluded), 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.

[0075] 〈Structural unit (a2)〉 The structural unit (a2) is a structural unit represented by formula (a2) and has an alcoholic hydroxy group, a phenolic hydroxy group or a carboxy group. TIFF2025081260000061.tif4095[In 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 -CH 2 - in the alkanediyl group may be replaced by -O-, -CO- or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. L a21represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, and the hydrocarbon group may have a substituent, and -CH contained in the hydrocarbon group 2 - may be replaced by -O-, -CO-, -S- or -SO 2 -. L a22 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms which may have a fluorine atom, and -CH contained in the chain hydrocarbon group 2 - may be replaced by -O- or -CO-. na2 represents any integer from 1 to 5. When na2 is 2 or more, a plurality of Ls a22 may be the same as or different from each other.] R a2 Examples of the halogen atom in R include a fluorine atom, an iodine atom, a chlorine atom, a bromine atom and the like. R a2 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, and still more preferably 1 or 2. 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 still more preferably a hydrogen atom or a methyl group.

[0076] 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 still more preferably 1 or 2. R a28 Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, and tert-butyl group. A a21 When -CH 2 - included in the alkanediyl group of A is replaced by -O-, -CO- or -NR a28 -, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the alkanediyl group. A a21 When -CH 2 - included in the alkanediyl group of A is replaced by -O-, -CO- or -NR a28As the group replaced by -, as described above, there may be mentioned a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylamino group, a peptide group, an alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyl-oxy group, an alkanediylsulfonyl group, an alkanediylthio group, an alkanediylamino group, and the like. These replaced groups include those similar to those exemplified in the present specification within the range where the upper limit of the number of carbon atoms permits. Among them, A a21 in the alkanediyl group of, the -CH 2 - being replaced by -O-, -CO- or -NR a28 -, the 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 -. Among them, *-CO-O-, *-CO-O-A a22 -CO-O-, *-O-A a22 -CO-O-, *-CO-NR a28 - are preferred. Here, A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site with the carbon atom to which R a2 is bonded. The alkanediyl group of A a22 includes alkanediyl groups similar to A a21 within the range where the upper limit of the number of carbon atoms permits. A a21 is preferably a single bond, *-CO-O- or *-CO-O-A a22 -CO-O-, more preferably a single bond, *-CO-O- or *-CO-O-CH 2 -CO-O-, and even more preferably a single bond or *-CO-O-.

[0077] L a21The hydrocarbon group in [description] is a (na2 + 1)-valent hydrocarbon group, and examples thereof include linear or branched chain hydrocarbon groups, monocyclic or polycyclic (including spiro rings, condensed rings, bridged rings, etc.) alicyclic hydrocarbon groups, and cyclic hydrocarbon groups such as aromatic hydrocarbon groups. A group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group) may also be used. L a21 Examples of the chain hydrocarbon group of [description] include divalent to hexavalent chain hydrocarbon groups such as alkanediyl groups, alkanetriyl groups, alkanetetrayl groups, alkanepentayl groups, and alkanhexayl groups. Examples of the alkanediyl group include, for example, an alkanediyl group similar to A a21 as described above. Examples of the alkanetriyl group include methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decanetriyl group, undecanetriyl group, dodecanetriyl group, tridecanetriyl group, tetradecanetriyl group, pentadecanetriyl group, hexadecanetriyl group, and heptadecanetriyl group. Examples of the alkanetetrayl group include methanetetrayl group, ethanetetrayl group, propanetetrayl group, butanetetrayl group, pentanetetrayl group, hexanetetrayl group, heptanetetrayl group, octanetetrayl group, nonanetetrayl group, decanetetrayl group, undecanetetrayl group, dodecanetetrayl group, tridecanetetrayl group, tetradecanetetrayl group, pentadecanetetrayl group, hexadecanetetrayl group, and heptadecanetetrayl group. Examples of the alkanepentayl group include methanepentayl group, ethanepentayl group, propanepentayl group, butanepentayl group, pentanepentayl group, and hexanepentayl group. In addition, groups in which one or more hydrogen atoms of the above-described groups are replaced with a bonding site, etc. are also included. The number of carbon atoms in the chain hydrocarbon group 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, yet even more preferably from 1 to 8, still even more preferably from 1 to 6, yet even more preferably from 1 to 5, and particularly preferably from 1 to 4. L a21 Examples of the monocyclic and polycyclic alicyclic hydrocarbon groups in a21 include the following alicyclic hydrocarbon groups and the like. The bonding site can be at any position. TIFF2025081260000062.tif46168For example, divalent to hexavalent alicyclic hydrocarbon groups such as cycloalkanediyl groups, cycloalkanetriyl groups, cycloalkanetetrayl groups, cycloalkanepentayl groups, cycloalkanehexayl groups, and the like can be mentioned. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclodecanetriyl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclodecanetetrayl group and polycyclic alicyclic hydrocarbon groups such as 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, norbornanetriyl group, adamantanetriyl group, decahydronaphthalenetriyl group, bicyclo[3.3.0]octanetriyl group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, bicyclo[3.3.0]octanetetrayl group can be mentioned. In addition, groups in which one or more hydrogen atoms of the above-mentioned groups are replaced by a bonding site and the like can also be mentioned. The number of carbon atoms in 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, yet even more preferably 6 to 12, and still even more preferably 6 to 10. L a21 Examples of the aromatic hydrocarbon group in [name of compound] include divalent to hexavalent aromatic hydrocarbon groups such as an arylene group, an arenetriyl group, an arenetetrayl group, an arenepentayl group, and an arenexayl group. Specific examples include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, a benzenetriyl group, a naphthalenetriyl group, an anthracenetriyl group, a biphenylenetriyl group, a phenanthrenetriyl group, a benzenetetrayl group, a naphthalenetetrayl group, an anthracenetetrayl group, a biphenylenetetrayl group, and a phenanthrenetetrayl group. Also included are groups in which one or more hydrogen atoms of the above-described groups are replaced by a bonding site. The number of carbon atoms in 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 yet even more preferably 6 to 10. Examples of the combined group of two or more types include a group combining an alicyclic hydrocarbon group and a chain hydrocarbon group, a group combining an aromatic hydrocarbon group and a chain hydrocarbon group, a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group, a chain hydrocarbon group, and an aromatic hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined respectively. Also, any group may be bonded to A a21 and L a22 and may be bonded. -CH 2 - contained in the hydrocarbon group is -O-, -S-, -SO 2-Or as a group replaced by -CO-, there are a hydroxy group, a carboxy group, a thiol group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkoxycarbonyloxy group, an alkylsulfonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyl-oxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a group formed by combining two or more of these groups, etc. Further, a group in which one or more hydrogen atoms of these groups are replaced at the bonding site, etc. are also included. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms allows.

[0078] Also, -CH 2 - contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO 2 - As the group, those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms allows are included. -CH contained in the combined group 2 - is replaced by -O-, -S-, -CO- or -SO 2 - As the group, the following groups, etc. are also included. The bonding site can be at any position. TIFF2025081260000063.tif26164L a21 The hydrocarbon group in may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 16 carbon atoms (the -CH 2 - contained in the alkyl group may be replaced by -O- or -CO-.), an acryloyloxy group or a methacryloyloxy group, etc. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. L a21The hydrocarbon group in [description] can have substituents such as a haloalkyl group by having a halogen atom as a substituent. Examples of the haloalkyl group include an alkyl fluoride group, an alkyl chloride group, an alkyl bromide group, an alkyl iodide group, etc. For example, a chloromethyl group, a bromomethyl group, an iodomethyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, etc. can be mentioned. The number of carbon atoms of the haloalkyl group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. L a21 The hydrocarbon group of [description] can have substituents such as an alkyl group by including a branched structure. a21 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, etc. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 10, still more preferably 1 to 8, even more preferably 1 to 6, still even more preferably 1 to 4, and even more preferably 1 to 3. L a21 The -CH 2 - in the hydrocarbon group of [description] is replaced by a group such as -O- or -CO-, so that L a21can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, a thiol group, a sulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an acryloyloxy group, a methacryloyloxy group, etc. 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. Examples of the above groups include the same ones as those exemplified in this specification. L a21 The substituents that the hydrocarbon group in L 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 (the -CH 2 - in the alkyl group may be replaced by -O- or -CO-).) are preferred, a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (the -CH 2 - in the alkyl group may be replaced by -O- or -CO-).) are more preferred, a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms are still more preferred, a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group are even more preferred, and a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, or an ethoxyethoxy group are still even more preferred. Also, when the alkanediyl group of L a21 is replaced by -O- or -CO-, etc., for example, *-L a23-X a21 -(L a23 represents an alkanediyl group having 1 to 8 carbon atoms, and X a21 represents -O-, -O-CO-, -CO-O- or -O-CO-O-, and * represents the bonding site with A a21 .) It is also preferable that it is so. L a21 is a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (provided that -CH 2 - 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 -CH 2 - contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -), or a group formed by combining 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 -CH 2 - contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH 2 - contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO 2 - or -CO-).) It is preferable that it is so, an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (provided that -CH 2 - 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 -CH 2 - contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -), 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 -CH 2 - contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH 2 - contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO 2 - or -CO-).) It is more preferable that it is so.

[0079] L a22 Examples of the chain hydrocarbon group having 1 to 12 carbon atoms represented by a22 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 of the chain hydrocarbon group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. -CH 2 Examples of the group in which - in the chain hydrocarbon group is replaced by -O- or -CO- include those similar to those exemplified in the present specification within the range allowed by the upper limit of the number of carbon atoms. L a22 The fluorine atom that a22 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 a21 is a single bond or a chain hydrocarbon group include, for example, the following structural units (hereinafter sometimes referred to as "structural units (a2-e)"). Among the following structural units, the structural units in which the methyl group corresponding to R a2 is replaced by a hydrogen atom or the like are also suitable structural units of the structural unit (a2) in the same manner as the following structural units. When the resin (A) contains the structural unit (a2-e), its content is 1 mol% or more, 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 of the resin (A). 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%.

[0080] 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 the 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. Also, when using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-1) described later. The structural unit (a2) may be contained alone or in combination of two or more kinds.

[0081] In the structural unit (a2), L a21 In the case where it is a cyclic hydrocarbon group, examples of the structural unit having a phenolic hydroxy group or a carboxy group include a structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF2025081260000065.tif30128[In the formula (a2-A), all the symbols have the same meanings as described above.]

[0082] Ra2 and A a21 includes groups similar to those exemplified by formula (a2). R a27 Examples of the halogen atom of R include a fluorine atom, a chlorine atom, an iodine atom, a bromine atom, and the like. R a27 Examples of the C1-C6 alkyl group which may have a halogen atom of R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The alkyl group is preferably a C1-C4 alkyl group, more preferably a C1-C3 alkyl group, still more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a27 Examples of the alkoxy group of R include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The alkoxy group is preferably a C1-C4 alkoxy group, more preferably a C1-C3 alkoxy group, still more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a27 Examples of the alkoxyalkyl group of R include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably a C2-C8 alkoxyalkyl group, more preferably a methoxymethyl group or an ethoxyethyl group, and still more preferably a methoxymethyl group. R a27Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. R a27 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a27 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R 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, still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. are more preferred. nA2 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, still more preferably 1 or 2. na21 is preferably 0, 1, 2, or 3, more preferably 0, 1, or 2, still 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, Aa21 When the bonding position of a21 is in the 1st position, it may be bonded to any of the 2nd to 8th positions, and A a21 When the bonding position of a21 is in the 2nd position, it may be bonded to the 1st position and any of the 3rd to 8th positions. Among them, when the bonding position of A

[0083] The structural unit (a2-A) includes structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. The structural unit (a2-A) includes structural units represented by formula (a2-2-1) to formula (a2-2-32), formula (a2-3-1) to formula (a2-3-24), and in the structural units represented by formula (a2-2-1) to formula (a2-2-32), formula (a2-3-1) to formula (a2-3-24), R a2 in the structural unit (a2-A) corresponding methyl group is replaced by a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. TIFF2025081260000066.tif107170

[0084] When the structural unit (a2-A) is included in the resin (A1), 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) can be incorporated into the resin (A) by polymerizing a compound that induces the structural unit (a2-A) (for example, a compound (a2-A’) in which the -CH 2 -C(-R a2 )- is in the state of CH 2 =C(-R a2 ) before cleavage). Further, for example, after polymerization using the structural unit (a1-4), it can be incorporated into the resin (A1) by treatment with an acid such as p-toluenesulfonic acid. Also, after polymerization using acetoxystyrene or the like, the structural unit (a2-A) can be incorporated into the resin (A1) by treatment with an alkali such as tetramethylammonium hydroxide.

[0085] In the structural unit (a2), when L a21 is a cyclic hydrocarbon group, examples of the structural unit having an alcoholic hydroxy group or a carboxy group include the structural unit represented by formula (a2-B) (hereinafter sometimes referred to as “structural unit (a2-B)”), the structural unit represented by formula (a2-C) (hereinafter sometimes referred to as “structural unit (a2-C)”), and the structural unit represented by formula (a2-D) (hereinafter sometimes referred to as “structural unit (a2-D)”). TIFF2025081260000068.tif45100[In formulas (a2-B) and (a2-C), R a2 represents the same meaning as in formula (a2). R a27 represents the same meaning as in formula (a2-A). L a25 represents -O- or *-O-(CH 2 ) k2 -CO-O-, k2 represents an integer from 1 to 7. * represents the bonding site with -CO-. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents an integer from 1 to 5. When nB2 is 2 or more, the plurality of X a2 may be the same as or different from each other. nB22 represents an integer from 0 to 8. When nB22 is 2 or more, the plurality of R a27 may be the same as or different from each other. nC22 represents an integer from 0 to 10. When nC22 is 2 or more, the plurality of R a27 may be the same as or different from each other.] L a25 is preferably -O-, -O-(CH 2 ) f1 -CO-O- (where f1 represents an integer from 1 to 4), 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 a27is preferably a halogen atom, a hydroxy group, a carboxy group, an optionally halogenated C1-C4 alkyl group, a C1-C4 alkoxy group or a C2-C8 alkoxyalkoxy group, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an 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.

[0086] Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from the monomers described in JP-A-2010-204646, the following structural units, and methyl groups or hydrogen atoms corresponding to R in the following structural units a2 which are replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. Among them, the structural units represented by any of formula (a2-B-1) to formula (a2-B-5) and formula (a2-C-1) to formula (a2-C-9) are preferred. When the resin (A1) 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 (A1). Also, it is 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and still more preferably 10 mol% or less. Specifically, 1 to 45 mol% is mentioned, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and still more preferably 1 to 10 mol%.

[0087] TIFF2025081260000070.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 an alkyl fluoride group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents any integer from 1 to 5. When nD2 is 2 or more, the groups in multiple parentheses may be the same or different from each other. nD22 represents any integer from 0 to 4. When nD22 is 2 or more, the plurality of a27 Rs may be the same or different from each other. However, 1 ≦ nD2 + nD22 ≦ 5.] R a21 and R a22 As the alkyl fluoride groups of R and R, independently of each other, a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, etc. may be mentioned. R a21 and R a22 are preferably a trifluoromethyl group. L a24 As the alkanediyl group of L, a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, etc. may be mentioned. L a24 is preferably a single bond or a methylene group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an 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. nD2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, even more preferably 1 or 2, and even more preferably 1. Further, preferably, nD2 is 1 and the group in parentheses is bonded to the para position. nD22 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2, even more preferably 0 or 1, and even more preferably 0.

[0088] As the structural unit (a2-D), a structural unit represented by the following formula (a2-D1) (hereinafter sometimes referred to as "structural unit (a2-D1)") is more preferable. TIFF2025081260000071.tif51108[In formula (a2-D1), R a2 、A a21 、R a27 、nD2 and nD22 have the same meanings as in formula (a2-D).] In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group. A a21 is preferably a single bond.

[0089] Examples of the structural unit (a2-D) include the structural units described below. In the structural units represented by the following formulas (a2-D-1) to (a2-D-8), the hydrogen atom corresponding to R a2 is replaced with a methyl group or the like, and in the structural units represented by formulas (a2-D-9) to (a2-D-16), R a2Structural units in which the methyl group corresponding thereto is replaced with 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 the formulas (a2-D-1) to (a2-D-8) are preferable, the structural units represented by the formulas (a2-D-1) to (a2-D-4) are more preferable, and the structural unit represented by the formula (a2-D-1) is even more preferable. TIFF2025081260000072.tif62167

[0090] When the resin (A) contains the structural unit (a2-D), the content thereof is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more with respect to all the structural units of the resin (A). Further, it is preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, and still more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 10 to 70 mol%, and still more preferably 10 to 65 mol%.

[0091] 〈Structural unit (a3)〉 The lactone ring possessed by the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an 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 cited.

[0092] 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. TIFF2025081260000073.tif51164[In the formulas (a3-1), (a3-2), (a3-3) and (a3-4), L a4 、L a5 and L a6Each independently represents a group represented by -O- or *-O-(CH 2 ) k3 -CO-O- (where k3 represents an integer from 1 to 7). L a7 represents -O-, *-O-L a8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding site with the carbonyl group. R a18 , R a19 , R a20 and R a24 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a3 represents -CH 2 - or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , R a23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer from 0 to 5. q1 represents an integer from 0 to 3. r1 represents an integer from 0 to 3. w1 represents an integer from 0 to 8. When p1, q1, r1 and / or w1 is 2 or more, the plurality of R a21 , R a22 , R a23 and / or R a25 may be the same as or different from each other.]

[0093] R a21 , Ra22 , R a23 and R a25 Examples of the aliphatic hydrocarbon group in R, R, and R include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, and tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom and the alkyl group which may have a halogen atom in R, R, R, and R are the same as those exemplified by R of formula (a1-0). a01 and the like. L a8 and L a9 Examples of the alkanediyl group in L and L include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. L a4 ~L a6 are each independently preferably -O- or *-O-(CH 2 ) k3 -CO-O- wherein k3 is an integer of 1 to 4, more preferably -O- and *-O-CH 2 -CO-O-, still more preferably an oxygen atom. L a7 is preferably -O- or *-O-L a8 -CO-O-, more preferably -O-, -O-CH 2 -CO-O- or -O-C 2 H 4 -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. Ra21 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 an integer of any one of 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)’. TIFF2025081260000074.tif4051(wherein R a24 、L a7 represents the same meaning as described above.)

[0094] 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. When the resin (A) contains the structural unit (a3), the total content rate is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and still more preferably 10 mol% or more with respect to all the structural units of the resin (A). Further, 70 mol% or less is mentioned, preferably 65 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still even more preferably 30 mol% or less, still more preferably 25 mol% or less, and still even more preferably 20 mol% or less. Specifically, 1 to 70 mol% is mentioned, preferably 3 to 70 mol%, more preferably 3 to 65 mol%, still more preferably 5 to 65 mol%, even more preferably 5 to 60 mol%, and still even more preferably 10 to 60 mol%. Further, the content rate 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 still more preferably 10 mol% or more with respect to 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, still more preferably 25 mol% or less, and still even more preferably 20 mol% or less. Specifically, 1 to 60 mol% is preferable, 3 to 60 mol% is more preferable, 3 to 55 mol% is still more preferable, 5 to 55 mol% is still more preferably, 5 to 50 mol% is even more preferable, and 10 to 50 mol% is still even more preferable.

[0095] 〈Structural unit (a4)〉 The structural unit represented by the formula (a4) is shown below. TIFF2025081260000076.tif3255[In the formula (a4), R 41 represents a hydrogen atom or a methyl group. R42 represents a saturated hydrocarbon group having a halogen atom with 1 to 24 carbon atoms, and -CH 2 - in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0096] R 42 The saturated hydrocarbon group represented by may include a linear or branched chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these, etc. Examples of the chain saturated 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 saturated hydrocarbon group include monocyclic alicyclic saturated hydrocarbon groups which are monocyclic cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group; polycyclic alicyclic saturated hydrocarbon groups which are polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group, and the following group (* represents the bonding site). Examples of the group formed by combination 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, -alkanediyl group - alicyclic saturated hydrocarbon group - alkyl group, etc. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, and hexane-1,6-diyl group; and branched alkanediyl groups such as propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom included in the saturated hydrocarbon group contained in 42 R 42 include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. The -CH 2 - in the saturated hydrocarbon group contained in 42

[0097] Examples of the structural unit (a4) include those in which R 42 is preferably a saturated hydrocarbon group having a fluorine atom. Examples of the structural unit (a4) in which R 42 is a saturated hydrocarbon group having a fluorine atom include a structural unit represented by the formula (a4-1) (hereinafter sometimes referred to as "structural unit (a4-1)"), a structural unit represented by the formula (a4-2) (hereinafter sometimes referred to as "structural unit (a4-2)"), a structural unit represented by the formula (a4-3) (hereinafter sometimes referred to as "structural unit (a4-3)"), and a structural unit represented by the formula (a4-A) (hereinafter sometimes referred to as "structural unit (a4-A)"). The structural unit represented by the formula (a4-1) is the structural unit shown below. TIFF2025081260000078.tif4864 In 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 with a fluorine atom or a cycloalkanediyl group having 3 to 12 carbon atoms with a fluorine atom. R 42f represents a hydrogen atom or a fluorine atom.]

[0098] L 41 Examples of the alkanediyl group in L 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 42f Examples of the alkanediyl group having a fluorine atom in L 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, a 2-methylbutane-1,4-diyl group having a fluorine atom, etc. 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 42f include monocyclic cycloalkanediyl groups having a fluorine atom such as a cyclobutane-1,3-diyl group having a fluorine atom, a cyclopentane-1,3-diyl group having a fluorine atom, a cyclohexane-1,4-diyl group having a fluorine atom, a cyclohexene-3,6-diyl group having a fluorine atom, a cycloheptane-1,4-diyl group having a fluorine atom, a cyclooctane-1,5-diyl group having a fluorine atom, and polycyclic cycloalkanediyl groups having a fluorine atom such as a norbornane-1,4-diyl group having a fluorine atom, a norbornane-2,5-diyl group having a fluorine atom, a 5-norbornene-2,3-diyl group having a fluorine atom, an adamantane-1,5-diyl group having a fluorine atom, an adamantane-2,6-diyl group having a fluorine atom. L 42f The number of fluorine atoms of the alkanediyl group having a fluorine atom and the cycloalkanediyl group having a fluorine atom in 42f may be 1 or more, and preferably 2 or more. L 42f The alkanediyl group having a fluorine atom and the cycloalkanediyl group having a fluorine atom in 42f are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0099] L 42fExamples of the perfluoroalkanediyl group 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 include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, a perfluoroadamantanediyl group, and the like.

[0100] 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 42f is preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and still more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0101] Examples of the structural unit (a4-1) include the structural units shown below and R in the structural unit (a4-1) in the following structural units. 41Examples thereof include structural units in which the methyl group corresponding thereto is replaced with a hydrogen atom. TIFF2025081260000079.tif98159 The structural unit represented by formula (a4-2) is the structural unit shown below. TIFF2025081260000080.tif5574[In formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH 2 - contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. R 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH 2 - contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, at least one of L 43f and R 43f has a fluorine atom, and the upper limit of the total number of carbon atoms of L 43f and R 43f is 21.]

[0102] Examples of the saturated hydrocarbon group in L 43f and R 43f include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these. Examples of the saturated hydrocarbon group in L 43f and R 43f are the same as the saturated hydrocarbon groups exemplified as the saturated hydrocarbon group of R 43f and R 43f in formula (a4) as long as the upper limit of the total number of carbon atoms of L 42 and R allows it.

[0103] As the saturated hydrocarbon group of L 43f a C1-C6 alkanediyl group or a group represented by formula (L43f-1) is preferable. TIFF2025081260000081.tif14119[In formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represents a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. L 47f represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. X 46f and X 47f each independently represents -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 .

[0104] In the group represented by formula (L43f-1), examples of the divalent saturated hydrocarbon group represented by L 45f L 46f and L 47f include linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and divalent saturated hydrocarbon groups formed by combining an alkanediyl group and a divalent alicyclic saturated hydrocarbon group. Specifically, examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, and the like. s is preferably 0.

[0105] Examples of the group represented by formula (L43f-1) include the following groups. In the following examples, * and ** each represent a bonding site, and ** is the bonding site with -O-CO-R 43f . TIFF2025081260000082.tif47140

[0106] R 43f is preferably a saturated hydrocarbon group having a fluorine atom. The structural unit represented by the formula (a4-2) in this case includes, for example, the structural units represented by the formula (a4-2A) or (formula a4-2B). TIFF2025081260000083.tif69102 [In the formula (a4-2A) and the formula (a4-2B), R 41 and L 43f represent the same as those in the formula (a4-2). R 43fA represents a saturated hydrocarbon group having 1 to 20 carbon atoms and having a fluorine atom. A 43f represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH 2 - contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** represents the bonding site with A 43f and represents the bonding site with A. R 43fB represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, in the formula (a4-2A), the total number of carbon atoms of L 43f and R 43fA is 21 or less, and in the formula (a4-2B), the total number of carbon atoms of L 43f , A 43f , X 43 and R 43fB is 21 or less, and among A 43f and R 43fB at least one has at least one fluorine atom. R 43fA The saturated hydrocarbon group of R 42 includes the same saturated hydrocarbon groups as those exemplified by R R 43fA is preferably an alkyl group having a fluorine atom and having 1 to 13 carbon atoms, a cycloalkyl group having a fluorine atom and having 3 to 12 carbon atoms, or a group combining them, *-(CF 2) n43f -R 42’ (*represents the bonding site with the carbonyl group. n43f represents an integer from 1 to 6. R 42’ represents a hydrogen atom or a fluorine atom.) Or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferable. A 43f and R 43fB 's saturated hydrocarbon group, as long as the upper limit of the number of carbon atoms permits, is the same saturated hydrocarbon group as exemplified by R 42 in formula (a4). A 43f is preferably a divalent chain saturated hydrocarbon group which may have a fluorine atom, a divalent alicyclic saturated hydrocarbon group or a group combining them, more preferably a divalent chain saturated hydrocarbon group having a fluorine atom, and even more preferably a fluoroalkanediyl group having 1 to 6 carbon atoms. R 43fBThe saturated hydrocarbon group which may have a fluorine atom is preferably a chain saturated hydrocarbon group, an alicyclic saturated hydrocarbon group which may have a fluorine atom, or a group combining them, more preferably an alkyl group having 1 to 12 carbon atoms which may have a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms or a group combining them, and even more preferably a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group, a perfluorooctyl group and other alkyl fluoride groups, a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, an adamantyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, a perfluoroadamantylmethyl group and the like.

[0107] In formula (a4-2B), *-A 43f -X 43 -R 43fB An example of the structure that the group represented by can take is the following structure (* is the bonding site with the carbonyl group). TIFF2025081260000084.tif14169

[0108] 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. TIFF2025081260000085.tif99167

[0109] 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 include structural units in which the methyl group corresponding to R in the following structural units is replaced by a hydrogen atom. JPEG2025081260000086.jpg111163

[0110] Examples of the structural unit (a4) also include the structural unit represented by formula (a4-3). TIFF2025081260000087.tif5576[In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH 2 - included in the saturated hydrocarbon group may be replaced by -O- or -CO-. R 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH 2 - included in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, at least one of L 44f and R 44f has a fluorine atom, and the upper limit of the total number of carbon atoms of L 44f and R 44f is 21.]

[0111] L 44f and R 44f Examples of the saturated hydrocarbon group in include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these. Examples of the saturated hydrocarbon group in L 44f and R 44f include, as long as the upper limit of the total number of carbon atoms of L 44f and R 44f allows, groups similar to the exemplified saturated hydrocarbon groups as the saturated hydrocarbon group of R 42 in formula (a4). L 44fis an alkanediyl group having 1 to 14 carbon atoms (the -CH contained in the alkanediyl group 2 - may be replaced by -O- or -CO-).), and it is preferably -(CH 2 ) j1 -, -(CH 2 ) j2 -O-(CH 2 ) j3 -, or -(CH 2 ) j4 -CO-O-(CH 2 ) j5 - (where j1 to j5 each independently represent an integer from 1 to 6).) is more preferable. Further, an alkanediyl group having 1 to 4 carbon atoms (one -CH contained in the alkanediyl group 2 - may be replaced by -O-, and one -CH contained in the alkanediyl group 2 -CH 2 - may be replaced by -CO-O- or -O-CO-).) is even more preferable. R 44f is preferably a saturated 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 saturated hydrocarbon group having 3 to 10 carbon atoms having a fluorine atom, or a group combining them, even more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, and still more preferably an alkyl group having 1 to 6 carbon atoms having a fluorine atom.

[0112] Examples of the structural unit represented by formula (a4-3) include, for example, the following structural units and the structural units represented by the following formulas, in which the methyl group corresponding to R 41 in structural unit (a4-3) is replaced by a hydrogen atom. TIFF2025081260000088.tif85165

[0113] TIFF2025081260000089.tif3686[In formula (a4-A), R 1represents 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-. * represents the bonding site with the carbon atom to which R 1 is bonded. L 1 represents an aliphatic hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH 2 - in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -SO 2 - 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 combine with L 1 to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH 2 - 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 within the plurality of parentheses may be the same as or different from each other.

[0114] R 1 Examples of the halogen atom and the alkyl group which may have a halogen atom in R a01 include the same ones as those exemplified by R a4 and R a5 in formula (a1-0) to formula (a1-2). R 1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0115] L 1Examples of the aliphatic hydrocarbon group in [the compound] include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.) alicyclic hydrocarbon group, and a group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group) may also be used. Examples of the chain hydrocarbon group include divalent to pentavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, and an alkanepentayl group. Examples of the alkanediyl group include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, 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, and a heptadecane-1,17-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. The number of carbon atoms 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. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups. The bonding site can be at any position. TIFF2025081260000090.tif46163For example, divalent to pentavalent alicyclic hydrocarbon groups such as cycloalkanediyl groups, cycloalkanetriyl groups, cycloalkanetetrayl groups, cycloalkanepentayl groups, etc. can be mentioned. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, etc. and Polycyclic alicyclic hydrocarbon groups such as spiro rings having a cycloalkanediyl group, norbornanediyl group or adamantanediyl group each having a cycloalkanediyl group, norbornanediyl group or adamantanediyl group spiro-bonded thereto, such as 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, spirocyclohexane-1,2'-cyclopentane-diyl group, spiroadamantane-2,3'-cyclopentane-diyl group, etc. can be mentioned. Moreover, groups in which one or more hydrogen atoms of the above-mentioned groups are replaced at the bonding site, etc. can be mentioned. 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. Examples of the group formed by combining two or more types include groups formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups and chain hydrocarbon groups may be combined respectively. Also, any group may be bonded to X 11 It may be bonded. Examples of groups 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-, etc.), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), 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-, etc.), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), Examples of such an alkyl group include a group in which a hydroxyl group is bonded to an alicyclic hydrocarbon group (for example, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group- etc.), a group in which an alicyclic hydrocarbon group, a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an chain hydrocarbon group (for example, *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group- etc.), and a group in which a chain hydrocarbon group, an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to an alicyclic hydrocarbon group (for example, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group- etc.). * is X 11 represents the binding site with Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites.

[0116] L 1 -CH contained in an aliphatic hydrocarbon group having 1 to 28 carbon atoms 2 -, -O-, -S-, -SO 2 It may be replaced by - or -CO-. L 1 -CH contained in an aliphatic hydrocarbon group having 1 to 28 carbon atoms 2 - is -O-, -S-, -SO 2 When it is replaced by - or -CO-, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the aliphatic hydrocarbon group. -CH contained in aliphatic hydrocarbon groups 2 -, -O-, -S-, -SO 2-Or the group replaced by -CO- includes 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 oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, a group formed by combining two or more of these groups, and the like. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. In addition, a group in which one or more hydrogen atoms of the above-described group are replaced by a bonding site, and the like are also included. In addition, -CH 2 - included in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO 2 - As the replaced group, those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits are included.

[0117] L 1 The aliphatic hydrocarbon group in may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms (the -CH 2 - included 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. -CH contained in the alkyl group 2- When it is replaced by -O- or -CO-, the number of carbon atoms before replacement is taken 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, etc. These replaced groups include the same groups as those exemplified in this specification within the range where the upper limit of the number of carbon atoms allows. The number of carbon atoms of the alkoxy group is preferably 1 to 9, 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 is preferably 2 to 9, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 9, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Also, as the group in which -CH 2 - in the alicyclic hydrocarbon group is replaced by -O- or -CO-, those similar to the groups exemplified in this specification are included within the range where the upper limit of the number of carbon atoms allows. L 1 Examples of the substituent that the aliphatic hydrocarbon group in L may have include a halogen atom, a haloalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms (the -CH 2 - in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). Fluorine atom, iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (the -CH 2 - in the alkyl group may be replaced by -O- or -CO-) are more preferable, and fluorine atom, iodine atom, trifluoromethyl group, methyl group, hydroxy group, or methoxy group are still more preferable. L 1 is R 3When it does not form an alkyl fluoride group and an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2 - may be replaced by —O— or —CO—), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (—CH contained in the alicyclic hydrocarbon group 2 - may be replaced by —O— or —CO—), or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2 - may be replaced by —O— or —CO—, and —CH contained in the alicyclic hydrocarbon group 2 - may be replaced by —O— or —CO—). Preferably, it is a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2 - may be replaced by —O— or —CO—), an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent, or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2 - may be replaced by —O— or —CO—). More preferably, it is a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2 - may be replaced by —O— or —CO—), an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent, a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2 - may be replaced by —O— or —CO—), or a group formed by combining an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent, a chain hydrocarbon group having 1 to 6 carbon atoms, and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (—CH contained in the chain hydrocarbon group 2- may be replaced by -O- or -CO-. It is more preferable that it is).

[0118] R 2 Examples of the C1-C8 fluoroalkyl group in include difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1-(trifluoromethyl)-1,2,2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis(trifluoro)methyl-2,2,2-trifluoroethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2-(perfluorobutyl)ethyl group, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group, perfluorohexyl group, perfluoroheptyl group, perfluorooctyl group. The carbon number of the fluoroalkyl group is preferably 1-6, more preferably 1-5, still more preferably 1-4, and even more preferably 1-3. R 3 The C1-C6 fluoroalkyl group in, as long as the upper limit of the carbon number permits, the C1-C6 fluoroalkyl groups exemplified in the examples of the fluoroalkyl group of R 2 are similarly exemplified. R 2 is R 3When it is an alkyl fluoride group having 1 to 6 carbon atoms, it is preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride group having 1 to 3 carbon atoms, still more preferably a trifluoromethyl group, a perfluoroethyl group or a perfluoropropyl group, and even more preferably a trifluoromethyl group. R 2 When R 3 is a hydrogen atom, it is preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride group having 1 to 5 carbon atoms, and still more preferably an alkyl fluoride group having 3 to 5 carbon atoms. R 3 When R 1 is bonded to L 3 to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, R 1 The group formed by bonding to L 2 includes, for example, the groups represented by the following formulas. Among the following formulas, * and ** represent the bonding sites, and the two **, one represents the bonding site with the hydroxy group, and the other represents the bonding site with R 1A L 1 is a part of the hydrocarbon group of L 3 and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. R 1 The number of carbon atoms of the alicyclic hydrocarbon group formed by bonding to L TIFF2025081260000091.tif25130R 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.

[0119] Examples of the structural unit (a4-A) include the following structural units. In these structural units, the methyl group corresponding to R 1 is replaced by a hydrogen atom, a halogen atom, a haloalkyl group or an alkyl group other than a methyl group, and R 1A structural unit in which a hydrogen atom corresponding to the following is replaced with a halogen atom, a haloalkyl group, or an alkyl group can also be cited as a specific example of the structural unit (a4-A). TIFF2025081260000092.tif227159

[0120] When the resin (A) contains the structural unit (a4), the content thereof is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and still more preferably 3 to 10 mol% with respect to all the structural units of the resin (A).

[0121] 〈Structural unit (a5)〉 Examples of the non-leaving hydrocarbon group of the structural unit (a5) include a group having a linear, branched, or cyclic hydrocarbon group. Among them, the structural unit (a5) is preferably a group having an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by the formula (a5-1). TIFF2025081260000093.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 atom 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 -CH 2 - contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.]

[0122] 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. The aliphatic hydrocarbon group having 1 to 8 carbon atoms includes, for example, 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. Examples of the alicyclic hydrocarbon group having a substituent include 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group. L 55 Examples of the divalent saturated hydrocarbon group in L 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 alkanediyl groups such as methylene group, ethylene group, propanediyl group, butanediyl group and pentanediyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl group and cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl group and norbornanediyl group.

[0123] L 55 Examples of the group in which -CH 2 - contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO- include, for example, 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. TIFF2025081260000094.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents a bonding site with L x1 .). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the total number of carbon atoms in L x1 and L x2 is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the total number of carbon atoms in L x3 and L x4 is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms in L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, the total number of carbon atoms in L x8 , L x9 and W x1 is 15 or less.

[0124] L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0125] Examples of the group represented by the formula (L1-1) include the following divalent groups. Examples of the group represented by the formula (L1-2) include the following divalent groups. Examples of the group represented by the formula (L1-3) include the following divalent groups. Examples of the group represented by the formula (L1-4) include the following divalent groups. TIFF2025081260000098.tif13168L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0126] As the structural unit (a5-1), there are the following structural units and the methyl group corresponding to R in the structural unit (a5-1) in the following structural units, where the methyl group is replaced by a hydrogen atom. 51 Examples thereof include structural units in which the methyl group corresponding to 51 is replaced by a hydrogen atom. TIFF2025081260000099.tif111150 When the resin (A) contains the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and even more preferably 3 to 15 mol% based on all the structural units of the resin (A).

[0127] 〈Structural unit (a6)〉 The structural unit (a6) is a structural unit having a -SO 2 - group, and preferably has a -SO 2 - group in the side chain. The structural unit having a -SO 2 - group may have a linear structure having a -SO 2 - group, or may have a branched structure having a -SO 2 - group, or may have a cyclic structure (monocyclic and polycyclic structures) having a -SO 2 - group. Preferably, it is a structural unit having a cyclic structure having a -SO 2 - group, and more preferably, it is a structural unit having a cyclic structure (sultone ring) containing -SO 2 -O-.

[0128] Examples of the sultone ring include 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 -SO 2 -O- as an atomic group constituting the ring, and examples thereof include rings represented by formula (T 1 -1) and formula (T 1 -2). The sultone ring is, like the ring represented by formula (T 1 -2), -SO 2 as an atomic group constituting the ring.In addition to -O-, it may further contain a heteroatom. Examples of the heteroatom include an oxygen atom, a sulfur atom, or a nitrogen atom, preferably an oxygen atom. TIFF2025081260000100.tif2977

[0129] The sultone ring may have a substituent. 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, etc.

[0130] 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 mentioned. 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, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumyl group, mesityl group, biphenyl group, phenanthryl group, 2,6-diethylphenyl group, and 2-methyl-6-ethylphenyl group. Examples of the aralkyl group include a benzyl group, phenethyl group, phenylpropyl group, naphthylmethyl group, and naphthylethyl group. Examples of the alkoxycarbonyl group include a group in which an alkoxy group such as a methoxycarbonyl group or ethoxycarbonyl group is bonded to a carbonyl group, preferably an alkoxycarbonyl group having 6 or fewer carbon atoms, more preferably a methoxycarbonyl group. Examples of the alkylcarbonyl group include an acetyl group, propionyl group, and butyryl group. From the viewpoint that the production of the monomer leading to the structural unit (a6) is easy, a sultone ring having no substituent is preferred.

[0131] As the sultone ring, a ring represented by the following formula (T1') is preferred. TIFF2025081260000101.tif2665[In the formula (T1'), X 11 represents an oxygen atom, sulfur atom, or methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or hydroxy group, a halogen atom, hydroxy group, cyano group, alkoxy group having 1 to 12 carbon atoms, aryl group having 6 to 12 carbon atoms, aralkyl group having 7 to 12 carbon atoms, glycidyloxy group, alkoxycarbonyl group having 2 to 12 carbon atoms, or 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 methylene group, more preferably a methylene group. R 41 Examples thereof include 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, more preferably 0.

[0132] 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. TIFF2025081260000102.tif44147

[0133] -SO 2 The structural unit having a - group preferably further has a group derived from a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, a methacryloylthio group, and the like. Among them, the monomer that leads to the structural unit (a6) is preferably a monomer having an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer.

[0134] The structural unit (a6) is preferably a structural unit represented by formula (a6-0). TIFF2025081260000103.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 -CH 2 - contained in the saturated hydrocarbon group may be replaced by -O-, -CO-, or -N(R d ). X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents the same meaning as described above. ma represents an integer from 0 to 9. When ma is 2 or more, a plurality of R's 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. R x Examples of the halogen atom of R include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R x Examples of the alkyl group of R include, 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 R 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 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 A include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and those obtained by combining two or more of these groups may also be used. Specifically, linear alkanediyl groups such as 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, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1,17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and 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 which 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. may be mentioned. A x The bonding position to the sultone ring of A can be at any position, but the one at the 1-position is preferred.

[0135] Examples of the structural unit (a6-0) include the following structural units. TIFF2025081260000104.tif93150

[0136] Among them, the structural units represented by formula (a6-1), formula (a6-2), formula (a6-6), formula (a6-7), formula (a6-8) and formula (a6-12) are preferred, and the structural units represented by formula (a6-1), formula (a6-2), formula (a6-7) and (a6-8) are more preferred. When the resin (A) contains the structural unit (a6), its content is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, and still more preferably 3 to 30 mol% based on all the structural units of the resin (A).

[0137] The resin (A) is preferably a resin composed of the structural unit (I), the structural unit (II), and the structural unit (a1), or a resin composed of the structural unit (I), the structural unit (II), the structural unit (a1), and the structural unit (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group), and more preferably at least one selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably the structural unit (a2-C) or the structural unit (a2-A). The structural unit (a3) is preferably at least one selected from the group consisting of the structural unit represented by the formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-4). In the resin (A), the total content of the structural unit (I), the structural unit (II), and the structural unit (a1) is preferably 40 mol% to 100 mol%, and more preferably 60 mol% to 100 mol% based on all the structural units of the resin (A). When the resin (A) contains the structural unit (a2-A), the total content of the structural unit (I), the structural unit (II), the structural unit (a1), and the structural unit (a2-A) is preferably 60 mol% to 100 mol%, and more preferably 85 mol% to 100 mol% based on all the structural units of the resin (A).

[0138] Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using a monomer that leads to these structural units. The content of each structural unit of the resin (A) can be adjusted by the amount of the monomer 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.

[0139] <Resins other than resin (A)> The resist composition of the present invention may contain a resin other than the resin (A). The resin other than the resin (A) is a resin that does not contain any of the structural unit (I), the structural unit (II), and the structural unit (a1). Examples thereof include a resin composed only of the structural unit (s), a resin composed of the structural unit (a1), the structural unit (a2), the structural unit (a3), and / or a structural unit derived from other known monomers, a resin composed of the structural unit (I), the structural unit (a1), the structural unit (a2), the structural unit (a3), and / or a structural unit derived from other known monomers, and a resin composed of the structural unit (II), the structural unit (a1), the structural unit (a2), the structural unit (a3), and / or a structural unit derived from other known monomers.

[0140] In addition, other resins include resins containing the structural unit (a2) (however, not containing either the structural unit (I) or the structural unit (II)). Examples thereof include a resin containing the structural unit (a1) and the structural unit (a2) (however, not containing either the structural unit (I) or the structural unit (II)) or a resin not containing the structural unit (a1) and containing the structural unit (a2). Also, as other resins, resins containing structural unit (a4) or structural unit (a5) (provided that they do not contain any of structural unit (I), structural unit (II), and structural unit (a1); hereinafter sometimes referred to as "resin (X)") and the like can be mentioned. Among them, as resin (X), a resin containing structural unit (a4) is preferable. When resin (X) contains structural unit (a4), in resin (X), the content of 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 with respect to the total of all structural units of 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, 20 to 100 mol% can be mentioned, 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 resin (X) contains structural unit (a5), the content of 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 with respect to the total of all structural units of 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, 20 to 100 mol% can be mentioned, 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%. Also, when resin (X) contains structural unit (a4) and structural unit (a5), the total content of structural unit (a4) and 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 with respect to the total of all structural units of resin (X). Further, it is 100 mol% or less. Specifically, 40 to 100 mol% can be mentioned, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and still more preferably 80 to 100 mol%. Examples of the structural units that resin (X) may further have include structural unit (a2), structural unit (a3), and structural units derived from other known monomers. The content rates of these structural units are within the same ranges as those exemplified for resin (A). Among them, resin (X) is preferably a resin composed of only structural unit (a4) and / or structural unit (a5). Each of the structural units constituting resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using the monomers that induce these structural units. The content rate of each structural unit that resin (X) has can be adjusted by the amount of monomers used in the polymerization. The weight average molecular weight of resin (X) is preferably 6,000 or more (more preferably 7,000 or more), 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).

[0141] When the resist composition of the present invention contains resin (X), its content is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, still more preferably 1 to 40 parts by mass, even more preferably 1 to 30 parts by mass, and even still more preferably 1 to 8 parts by mass with respect to 100 parts by mass of resin (A).

[0142] The content rate of the resin (A) in the resist composition is preferably 20% by mass or more and 100% by mass or less, more preferably 50% by mass or more and 99% by mass or less, with respect to the solid content of the resist composition. Further, when containing a resin other than the resin (A), the total content rate of the resin (A) and the resin other than the resin (A) is preferably 60% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 99% by mass or less, still more preferably 80% by mass or more and 99% by mass or less, and even more preferably 90% by mass or more and 99% by mass or less, with respect to the solid content of the resist composition. The solid content of the resist composition and the content rate of the resin with respect thereto can be measured by known analysis means such as liquid chromatography or gas chromatography.

[0143] <Acid generator (B)> As the acid generator (B), either a nonionic compound or an ionic compound may be used. Examples of the nonionic compound include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxy ketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), etc. Representative examples of the ionic compound include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of the anion of the onium salt include sulfonic acid anion, benzenesulfonyl anion, sulfonylimide anion, sulfonylmethide anion, and carboxylic acid anion, etc. Further, the acid generator (B) may be a part of the structural unit constituting the resin contained in the resist composition of the resist of the present invention, like the structural unit (I).

[0144] As the acid generator (B), compounds that generate acid upon irradiation, as described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc., can be used. Further, compounds produced by known methods may also be used. The acid generator (B) may be used alone or in combination of two or more. Further, the acid generator (B) may be an acid generator having an acid-labile group. For example, the compound or resin serving as the acid generator may contain a partial structure serving as the acid-labile group, and the acid-labile group preferably contains the above-described group (1) or group (2).

[0145] A preferred form of the acid generator (B) includes a salt represented by formula (B1) (hereinafter sometimes referred to as "salt (B1)" or "acid generator (B1)") or a salt represented by formula (B2) (hereinafter sometimes referred to as "salt (B2)" or "acid generator (B2)"). TIFF2025081260000105.tif1492[In formula (B1), all symbols represent the same meaning as described above.] L b1 As the (nb1 + 1)-valent hydrocarbon group of L, from a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent group formed by combining two or more of these, nb1 hydrogen atoms are removed, 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, and even more preferably 1 to 24. Examples of the chain hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, heptadecyl group, and the like. Examples of the alkenyl group include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, isooctenyl group, and nonenyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 24, still more preferably 1 to 20, even more preferably 1 to 18, even further preferably 1 to 12, and even further preferably 1 to 10. Examples of the alicyclic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, and the like. Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include norbornyl group, adamantyl group, and the like. Examples of the cycloalkyl group in which two or more rings are condensed include bicyclo[4,4,0]decane group, steroid group (steroid skeleton), and the like. 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 cyclopentyl group, cyclohexyl group, norbornyl group, and adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include those represented by the following formula. TIFF2025081260000106.tif26168 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, still more preferably 3 to 18, even more preferably 3 to 12, even still more preferably 3 to 10, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, still more preferably 6 to 18, even more preferably 6 to 12, and even still more preferably 7 to 12. Examples of the aromatic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorenyl group, and the like. More specifically, examples of the aromatic hydrocarbon group include those represented by the following formula. TIFF2025081260000107.tif1085 The number of carbon atoms in the aromatic hydrocarbon group is preferably 4 to 24, more preferably 4 to 20, still more preferably 4 to 18, even more preferably 5 to 14, even still more preferably 5 to 10, and even more preferably 6 to 10. L b1 When -CH 2 - contained in the hydrocarbon group of is replaced by -O-, -CO-, -S- or -SO 2 -, the number of carbon atoms before replacement is taken as the number of carbon atoms in the hydrocarbon group. L b1 Among the hydrocarbon groups of , as the group in which -CH 2 - contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO 2 -, there are a hydroxy group (a group in which -CH 2 - contained in the methyl group is replaced by -O-), a carboxy group (a group in which -CH 2 -CH2 - is a group replaced by -O-CO-, a carbonyl group (-CH contained in a methylene group) 2 - is a group replaced by -CO-, an oxy group (-CH contained in a methylene group) 2 - is a group replaced by -O-, an alkoxy group (-CH at any position contained in an alkyl group) 2 - is a group replaced by -O-, an alkoxycarbonyl group (-CH at any position contained in an alkyl group) 2 -CH 2 - is a group replaced by -O-CO-, an alkylcarbonyl group (-CH at any position contained in an alkyl group) 2 - is a group replaced by -CO-, an alkylcarbonyloxy group (-CH at any position contained in an alkyl group) 2 -CH 2 - is a group replaced by -CO-O-, an alkanediyl oxy group (-CH at any position contained in an alkanediyl group) 2 - is a group replaced by -O-, an alkanediyl oxycarbonyl group (-CH at any position contained in an alkanediyl group) 2 -CH 2 - is a group replaced by -O-CO-, an alkanediylcarbonyl group (-CH at any position contained in an alkanediyl group) 2 - is a group replaced by -CO-, an alkanediylcarbonyl oxy group (-CH at any position contained in an alkanediyl group) 2 -CH 2 - is a group replaced by -CO-O-, etc. are exemplified. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. L b1 Among the hydrocarbon groups of, -CH contained in an alicyclic hydrocarbon group 2 - is -O-, -CO-, -S- or -SO 2Examples of the group replaced by - include groups containing structures such as cyclic ethers, cyclic ketones, cyclic esters (lactones), cyclic thioethers, cyclic acetals, cyclic sulfonic acid esters (sultones), etc. Specifically, examples include alicyclic hydrocarbon groups represented by the following formulas. The bonding position of the alicyclic hydrocarbon group exemplified by the following formulas can be any position. TIFF2025081260000108.tif48165L b1 Among the hydrocarbon groups of, the -CH contained in the aromatic hydrocarbon group 2 - may be replaced by -O- or -S-, and as the group in which -CH 2 - is replaced by -O- or -S-, examples include groups derived from a furan ring or a thiophene ring, respectively. Specifically, examples include aromatic hydrocarbon groups represented by the following formulas. TIFF2025081260000109.tif1326Examples 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 group combining the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be a condensed ring. L b2 Examples of the divalent hydrocarbon group of include divalent chain hydrocarbon groups, divalent alicyclic hydrocarbon groups, divalent aromatic hydrocarbon groups, and groups combining two or more of these, and groups obtained by removing one hydrogen atom from a monovalent hydrocarbon group and bonding to Y b1 . L b2 Examples of the divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group combining two or more of these of are, within the range permitted by the upper limit of the number of carbon atoms, groups obtained by removing one hydrogen atom from the monovalent chain hydrocarbon group, monovalent alicyclic hydrocarbon group, monovalent aromatic hydrocarbon group, and monovalent group combining two or more of these exemplified by L b1 . L b1 and L b2 Examples of the substituent that the hydrocarbon group of L and L may have include a halogen atom, a cyano group, a nitro group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. L b1 and L b2 When L and L are a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group, substantially, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, L b1 and L b2 When -CH- of the chain hydrocarbon group contained in the hydrocarbon group of L and L 2 - is replaced by -O-, -CO-, -S- or -SO 2 -, the hydrocarbon group of L b1 and L b2 may substantially have substituents such as a hydroxy group, a carboxy group, a carbonyl group, an oxycarbonyl group, a carbonyloxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, an alkylsulfonyl group, and the like. L b1 and L b2 The number of the substituents that L and L may have is not particularly limited, and they may have a plurality of substituents. Y b1 Examples of the cyclic hydrocarbon group of Y include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of Y are each the same as the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified by L b1 and when they have no substituent, they may be a monovalent alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 Examples of the substituent that the methyl group of Y may have include a halogen atom, a cyano group, a hydroxy group, a nitro group, and the like. Y b1Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, or a hydrocarbon group having 1 to 18 carbon atoms which may have a halogen atom, a cyano group or a nitro group (the -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -).) and the like. Y b1 The number of carbon atoms of the hydrocarbon group that the cyclic hydrocarbon group of Y b1 may have is not included in the number of carbon atoms of the cyclic hydrocarbon group of Y. Examples of the halogen atom include the same halogen atoms as those exemplified as the substituent of L b1 and L b2 . Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y 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, the same groups as those exemplified by the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group combining two or more of these groups exemplified by L b1 . Further, examples of the group in which -CH 2 - in the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y 2 may have as a substituent is replaced by -O-, -S-, -CO- or -SO b1 - include, within the range permitted by the upper limit of the number of carbon atoms, the same groups as those exemplified by the group in which -CH 2 - in the hydrocarbon group of L 2 is replaced by -O-, -S-, -CO- or -SO b1 . Further, the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y

[0146] 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)"). TIFF2025081260000110.tif30117[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 C1-C6 perfluoroalkyl group or a C1-C6 alkyl group. 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 -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. 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.]

[0147] Q b1 、Q b2 、Q b3 and Q b4 Examples of the perfluoroalkyl group of include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group and a perfluorohexyl group, etc. Q b1 、Q b2 、Qb3 and Q b4 Examples of the alkyl group of 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, a hexyl group, and the like. Q b1 and Q b2 is Q b1 and Q b2 It is preferable that at least one of b2 contains 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. b3 is preferably a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms. b4 is preferably a hydrogen atom or a fluorine atom. 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-.

[0148] L b3 Examples of the hydrocarbon group in b3 include the same hydrocarbon groups as those exemplified for L in formula (B1) within the range allowed by the upper limit of the number of carbon atoms. b1 L b3 is a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (the -CH 2 - contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH 2 - contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO 2 -), or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent (the -CH2 - may be replaced by -O- or -S-. ) Or it is preferably a group in which two or more of these groups are combined, 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). In addition, -CH 2 When - is replaced by -O- or -CO-, the number thereof is preferably 1 to 4, and one -CH 2 -CH 2 - is replaced by -O-CO- or -CO-O-, or one -CH 2 -CH 2 -CH 2 - is preferably replaced by -O-CO-O-. TIFF2025081260000111.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, and -CH 2 - 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, and -CH 2 - in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -, and -CH 2 - 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.] In the formula (Lb3-1), L b31 The chain hydrocarbon group of may be the same group as the chain hydrocarbon group exemplified by L b1 as long as the upper limit of the number of carbon atoms permits. In the formula (Lb3-1), W b3The alicyclic hydrocarbon group and the aromatic hydrocarbon group of L may be the same groups as the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified in L as long as the upper limit of the number of carbon atoms permits. b1 Examples thereof include the same groups as the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified in b1 . In formula (Lb3-1), the substituents that the chain hydrocarbon group of L may have and the substituents that the alicyclic hydrocarbon group and the aromatic hydrocarbon group of W may have are the same groups as the substituents exemplified as the substituents that the hydrocarbon group of L may have. b31 b3 b1 L b31 is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (the -CH- contained in the alkanediyl group may be replaced by -O- or -CO-). 2 Among them, as the alicyclic hydrocarbon group and the aromatic hydrocarbon group of W, the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below are preferable. In the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below, * and ** represent the bonding sites, * represents the bonding site with X b3 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 . Further, in the alicyclic hydrocarbon group represented below, the -CH- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. When the -CH- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO 2 -, it is preferably to form an ether ring, an ester ring (lactone), a carbonate ester ring, a sulfonic acid ester ring (sultone) or an acetal ring. 2 2 In formula (B1-A1), L b2 is a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (the -CH- contained in the chain hydrocarbon group 2- may be replaced by -O- or -CO-. ) is preferred, and is a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O- or *-L b21 -X 2 -L b22 -**(L b21 and L b22 Either one of them 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 and represents the bonding site with Y. However, L b21 , X 2 and L b22 The total number of carbon atoms of is 12 or less. ) is more preferably the case. In formula (B1-A1), Y b1 is an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (the -CH 2 - in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO 2 -). It is preferably, an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms (the -CH 2 - in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO 2 -), or an optionally substituted aromatic hydrocarbon group having 6 to 18 carbon atoms. More preferably, it is an optionally substituted alicyclic hydrocarbon group having 3 to 16 carbon atoms (the -CH 2 - in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO 2 -), or an optionally substituted aromatic hydrocarbon group having 6 to 10 carbon atoms. More 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 optionally substituted groups of the cyclic hydrocarbon group of Y b1 , R Yc represents a hydrogen atom or an optionally substituted group of the cyclic hydrocarbon group of Y b1 , and * represents Lb2 represents a binding site with. The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formula are not specifically shown in the following formula, but may have substituents that the cyclic hydrocarbon group of Y b1 may also have. As the anion represented by formula (B1-A1), anions represented by formula (B1-A1-1) to formula (B1-A1-85) [hereinafter, may be referred to as "anion (B1-A1-1)" etc. according to the formula number] are preferable, and anions represented by any of formula (B1-A1-1) to formula (B1-A1-4), formula (B1-A1-9), formula (B1-A1-10), formula (B1-A1-24) to formula (B1-A1-33), formula (B1-A1-36) to formula (B1-A1-40), and formula (B1-A1-47) to formula (B1-A1-85) are more preferable. TIFF2025081260000114.tif234161

[0149] TIFF2025081260000115.tif249153

[0150] TIFF2025081260000116.tif254163

[0151] In formula (B1-A1-1) to formula (B1-A1-85), R i2 ~R i7 are each independently, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, a chain 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. Specific examples of the anion represented by formula (B1-A1) include the anions described in JP-A-2010-204646.

[0152] As the anion represented by the formula (B1-A1), preferably, anions represented by the formulas (B1a-1) to (B1a-70) can be mentioned. Among them, an anion represented by any one of the formulas (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), and (B1a-35) to (B1a-70) is preferable. TIFF2025081260000117.tif183158

[0153] TIFF2025081260000118.tif252162

[0154] TIFF2025081260000119.tif68163

[0155] The anion represented by the formula (B1-A2) is represented by the following formula. TIFF2025081260000120.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 -CH 2 - 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.]

[0156] In the formula (B1-A2), the hydrocarbon group of L b2 and the cyclic hydrocarbon group of Y b1 are exemplified within the range allowed by the upper limit of the number of carbon atoms, and L in the formula (B1) b2The hydrocarbon group and Y b1 Examples of the cyclic hydrocarbon group of are the same as those exemplified. L b2 The hydrocarbon group, Y b1 Regarding the methyl group of and the substituents that the cyclic hydrocarbon group may have, L in formula (B1) b2 The hydrocarbon group, Y b1 Examples of the same substituents that the methyl group of and the cyclic hydrocarbon group may have are given. These hydrocarbon groups, methyl group and cyclic hydrocarbon group 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 (the -CH 2 - 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 the -CH 2 - contained in the chain hydrocarbon group may be replaced by -O- or -CO-). * represents the bonding site with the benzene ring to which SO 3 - is bonded. L b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms.).), still more preferably, *-CO-O-. Y b1 As Y, a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (the -CH 2 - contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO 2 -).) is preferably, an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH 2 - contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO 2 -).) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent is more preferable, Y in formula (B1-A1) 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 substitution of the benzene ring with respect to the bonding position of SO 3 - to have the following structure. TIFF2025081260000121.tif29107[In the above formula, L b2 、Y b1 、R b1 、nb3 have the same meanings as in formula (B1-A2).] When nb4 is 2 or more, a plurality of L b2 and Y b1 are preferably the same group as each other.

[0157] R b1 Examples of the alkyl group having 1 to 6 carbon atoms for R include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, and hexyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R b1 Examples of the halogen atom for R include fluorine atom, chlorine atom, bromine atom, and iodine atom. Examples of the group in which -CH 2 - contained in the alkyl group is replaced by -O- or -CO- include hydroxy group, carboxy group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, oxy group, carbonyl group, etc. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. R b1is, independently of each other, a halogen atom or an alkyl group having 1 to 4 carbon atoms (wherein -CH 2 - may be replaced by -O- or -CO-). Preferably, it is a fluorine atom, an iodine atom or an alkyl group having 1 to 3 carbon atoms (wherein -CH 2 - may be replaced by -O- or -CO-). More preferably, it is a fluorine atom, an iodine atom, a hydroxy group, a methoxy group or a methyl group. nb3 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, R b1 is preferably a halogen atom, and R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2, one of R b1 is preferably a halogen atom and the other is preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms, and one of R b1 is more preferably a fluorine atom or an iodine atom and the other is preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 3 carbon atoms.

[0158] Examples of the anion represented by the formula (B1-A2) include the following anions. Among them, the anions represented by the formulas (B2a-1) to (B2a-20) are preferred, and the anions represented by the formulas (B2a-1) to (B2a-11) and (B2a-16) to (B2a-20) are more preferred. In the following anions, some of the R b1 are omitted and may contain substituents not shown. TIFF2025081260000122.tif102153

[0159] TIFF2025081260000123.tif1399[In the formula (B2), A 1 represents a nitrogen atom or a carbon atom. L b2’ represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH contained in the hydrocarbon group 2 - may be replaced by -O-, -S-, -CO- or -SO 2 -. Y b1’ represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH contained in the cyclic hydrocarbon group 2 - may be replaced by -O-, -S-, -CO- or -SO 2 -. nb5 represents an integer of 2 or 3. When nb5 is 2, A 1 is a nitrogen atom, and when nb5 is 3, A 1 is a carbon atom. The groups in a plurality of parentheses may be the same as or different from each other, and the groups in two parentheses may be bonded to form a ring containing A 1 . Z2 + represents an organic cation.] In formula (B2), L b2’ and Y b1’ Examples of the hydrocarbon group, cyclic hydrocarbon group and substituent are the same groups as L b2 and Y b1 in formula (B1-A1). In formula (B2), L b2’ is a single bond, *-L b23 -, *-L b23 -X 2 - or *-L b23 -X 2 -W 2 -X 3 -(L b23 represents a chain hydrocarbon group having 1 to 6 carbon atoms which may have a fluorine atom. X 2 and X 3 each independently represent -O-, -CO-O-, -O-CO-, -O-CO-O- or -O-. W 2 represents an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH contained in the alicyclic hydrocarbon group 2 - may be replaced by -O- or -CO-. * is SO 2Represents a binding site with (...).) It is preferably (...). Y b1’ is a methyl group having a fluorine atom or a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (the -CH included in the cyclic hydrocarbon group 2 - is -O-, -CO-, -S- or -SO 2 - may be replaced by (...).) It is preferably a trifluoromethyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH included in the alicyclic hydrocarbon group 2 - is -O-, -S-, -CO- or -SO 2 - may be replaced by (...).) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent is more preferable. Specifically, it is preferably a trifluoromethyl group or a group represented by the formula (Y1) to the formula (Y36) exemplified in the formula (B1-A1). In the formula (B2), two -SO 2 -L b2’ -Y b1’ together form a ring containing A 1 When forming a ring, for example, an anion represented by the formula (B2’) can be mentioned. TIFF2025081260000124.tif21112 [In the formula (B2’), A 1 、Y b1’ 、L b2’ and nb5 represent the same meaning as in the formula (B2). W b4 represents a disulfonylimide ring or a disulfonylmethide ring having 2 to 12 carbon atoms which may have a fluorine atom. W b4 The disulfonylimide ring or the disulfonylmethide ring of W preferably has 3 to 12 carbon atoms, more preferably 3 to 6 carbon atoms, and the hydrogen atom of the methylene group contained in the ring is preferably replaced by a fluorine atom.

[0160] Examples of the anion of the salt represented by the formula (B2) include the following. Among them, an anion represented by the formula (B3a-1) or the formula (B3a-2) is preferable. TIFF2025081260000125.tif174163

[0161] In another form of the acid generator (B), a salt in which the sulfonic acid anion in the salt represented by the formula (B1) is replaced with a carboxylic acid anion or the like is also preferably used as the acid generator (B). Examples of the carboxylic acid anion include the following. TIFF2025081260000126.tif41155

[0162] Z + and Z2 + Examples of the organic cation of Z1 in the structural unit represented by the formula (I) as the organic cation of + and Z2 are the same organic cations as those of the organic cation of Z1 in the structural unit represented by the formula (I). Z + and Z2 + are more preferably an arylsulfonium cation or an aryliodonium cation, and specifically, a cation represented by any of the formulas (b2-1) to (b2-5) is even more preferable.

[0163] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. Examples of the acid generator (B) preferably include a combination of an anion represented by any of the formulas (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), (B1a-35) to (B1a-70), (B2a-1) to (B2a-11), (B2a-16) to (B2a-20), (B3a-1) to (B3a-3) or (B3a-11) to (B3a-14) and a cation (b2-1), a cation (b2-2), a cation (b2-3), a cation (b2-4) or a cation (b2-5).

[0164] As the acid generator (B), those represented by formula (B1-1) to formula (B1-105), formula (B2-1) to formula (B2-20), and formula (B3-1) to formula (B3-28) are preferably mentioned. Among them, those containing an arylsulfonium cation are preferred, and those represented by formula (B1-1) to formula (B1-3), formula (B1-5) to formula (B1-7), formula (B1-11) to formula (B1-14), formula (B1-20) to formula (B1-26), formula (B1-29), formula (B1-31) to formula (B1-105), formula (B2-1) to formula (B2-20), and formula (B3-1) to formula (B3-28) are particularly preferred. TIFF2025081260000127.tif176161

[0165] TIFF2025081260000128.tif254159

[0166] TIFF2025081260000129.tif254165

[0167] TIFF2025081260000130.tif254160

[0168] TIFF2025081260000131.tif248162

[0169] TIFF2025081260000132.tif250151

[0170] TIFF2025081260000133.tif187159

[0171] The content of the acid generator (B1) is preferably 30% by mass or more and 100% by mass or less, more preferably 50% by mass or more and 100% by mass or less, and even more preferably substantially only the acid generator (B1), based on the total amount of the acid generator (B). The content rate of the acid generator (B) is preferably 1% by mass or more, more preferably 3% by mass or more, preferably 30% by mass or less, and more preferably 25% by mass or less, based on the solid content of the resist composition. Further, the content of the acid generator (B) is preferably 1 part by mass or more, more preferably 3 parts by mass or more, preferably 30 parts by mass or less, and more preferably 25 parts by mass or less, relative to 100 parts by mass of the resin (A). The resist composition of the present invention may contain one kind of the acid generator (B) alone or may contain a plurality of kinds thereof.

[0172] <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 analysis 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.

[0173] <Quencher (C)> Examples of the quencher (C) include salts that generate an acid having a lower acidity than the acid generated from the structural unit (I) and the acid generator (for example, the acid generator (B)), and basic nitrogen-containing organic compounds. The content rate 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 still more preferably about 0.1 to 7% by mass, based on the solid content of the resist composition.

[0174] <Salt that generates an acid with a lower acidity than the acid generated from the structural unit (I) and the acid generator> In the salt that generates an acid with a lower acidity than the acid generated from the structural unit (I) and the acid generator, the acidity is indicated by the acid dissociation constant (pKa). The salt that generates an acid with a lower acidity than the acid generated from the structural unit (I) and the acid generator is a salt in which the acid dissociation constant of the acid generated from the salt is usually -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. Examples of the salt that generates an acid with a lower acidity than the acid generated from the structural unit (I) and the acid generator include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. As the salt that generates an acid with a lower acidity than the acid generated from the acid generator, preferably, it is a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (a salt having a carboxylic acid anion), more preferably, it is the weak acid inner salt (D), and still more preferably, among the weak acid inner salts (D), it is a diphenyliodonium salt containing a phenyl group substituted with a carboxylic acid anion. TIFF2025081260000134.tif96153

[0175] 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 examples thereof include salts represented by the following formula. TIFF2025081260000135.tif1692[In formula (D), R D1 and R D2Each 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. When n’ is 2 or more, a plurality of R D2 may be the same or different.] R D1 and R D2 Examples of the hydrocarbon group include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, nonyl group and the like. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and may be either saturated or unsaturated. Examples include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclononyl group, cyclododecyl group, norbornyl group, adamantyl group and the like. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, 1-naphthyl group, 2-naphthyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-propylphenyl group, 4-isopropylphenyl group, 4-butylphenyl group, 4-t-butylphenyl group, 4-hexylphenyl group, 4-cyclohexylphenyl group, anthryl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, biphenyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like. Examples of the group formed by combining these include an alkyl-cycloalkyl group, a cycloalkyl-alkyl group, an aralkyl group (e.g., a phenylmethyl group, a 1-phenylethyl group, a 2-phenylethyl group, a 1-phenyl-1-propyl group, a 1-phenyl-2-propyl group, a 2-phenyl-2-propyl group, a 3-phenyl-1-propyl group, a 4-phenyl-1-butyl group, a 5-phenyl-1-pentyl group, a 6-phenyl-1-hexyl group, etc.). Examples of the alkoxy group include a methoxy group, an ethoxy group, etc. Examples of the acyl group include an acetyl group, a propanoyl group, a benzoyl group, a 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 a fluorine atom, a chlorine atom, a 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. More specifically, the following salts are included. TIFF2025081260000136.tif72165

[0176] Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. Examples of the amines include aliphatic amines and aromatic amines. Examples of the aliphatic amines include primary amines, secondary amines and tertiary amines. Examples of the amine include 1-naphthylamine, 2-naphthylamine, aniline, diisopropyl aniline, 2-, 3- or 4-methyl aniline, 4-nitroaniline, N-methyl aniline, N,N-dimethyl aniline, 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 diisopropyl aniline are preferable, and 2,6-diisopropyl aniline is more preferable. Examples of ammonium salts include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, and choline.

[0177] <Other Components> The resist composition of the present invention may, if necessary, contain components other than the above-described components (hereinafter sometimes referred to as "other components (F)"). There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used.

[0178] <Preparation of Resist Composition> The resist composition of the present invention can be prepared by mixing the resin (A), optionally the acid generator (B), a resin other than the resin (A), the solvent (E), the quencher (C), and other components (F), etc. The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40°C according to the type of resin, etc. and the solubility of the resin, etc. in the solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is also not particularly limited, and stirring and mixing, etc. can be used. After mixing the components, it is preferable to filter using a filter with a pore size of about 0.003 to 0.2 μm.

[0179] <Method for Manufacturing 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 It includes the step of developing the composition layer after heating. To apply the resist composition onto a substrate, it can usually be performed by a commonly used apparatus such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers and organic substrates with a resist film or the like formed on the surface. Before applying the resist composition, the substrate may be cleaned, or an antireflection film or the like may be formed on the substrate. By drying the applied composition, the solvent is removed to form a composition layer. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-bake), or by using a decompression device. The heating temperature is preferably 50 to 200 °C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during decompression drying is preferably about 1 to 1.0×10 5 Pa. The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, those that emit laser light in the ultraviolet region such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F 2 excimer laser (wavelength 157 nm), those that convert laser light from a solid laser light source (such as YAG or semiconductor laser) into harmonic laser light in the far ultraviolet region or vacuum ultraviolet region and emit it, those that irradiate electron beams, those that irradiate extreme ultraviolet light (EUV), etc., various types can be used. In this specification, irradiating these radiations may be collectively referred to as "exposure" in some cases. During exposure, usually, exposure is performed through a mask corresponding to the required pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask. The composition layer after exposure is subjected to a heat treatment (so-called post-exposure bake) to promote the deprotection reaction in the acid-labile group. The heating temperature is usually about 50 to 200 °C, preferably about 70 to 150 °C. A chemical treatment (silylation) may be performed to adjust the hydrophilicity or hydrophobicity of the resin on the surface side of the composition after heating. Also, before development, the steps of applying, drying, exposing, and heating the resist composition may be repeated on the composition layer after exposure. The heated composition layer is usually developed using a developer with a developing apparatus. Examples of the developing method include 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 developer as follows, a positive resist pattern or a negative resist pattern can be manufactured. When manufacturing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be various alkaline aqueous solutions used in this field. For example, aqueous solutions of tetramethylammonium hydroxide and (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline) can be mentioned. The alkaline developer may contain a surfactant. After development, it is preferable to wash the resist pattern with ultrapure water and then remove the water remaining on the substrate and the pattern. When manufacturing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic-based developer") is used as the developer. Examples of the organic solvent contained in the organic-based developer include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole, etc. In the organic-based developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and even more preferably substantially only the organic solvent. Among them, as the organic developing solution, a developing solution containing butyl acetate and / or 2-heptanone is preferable. In the organic developing solution, the total content ratio of butyl acetate and 2-heptanone is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and still more preferably substantially only butyl acetate and / or 2-heptanone. The organic developing solution may contain a surfactant. Further, the organic developing solution may contain a small amount of water. During development, development may be stopped by substituting with a solvent of a different type from the organic developing solution. It is preferable to wash the resist pattern after development with a rinse solution. The rinse solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After washing, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

[0180] <Use> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, particularly as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for semiconductor microfabrication.

Examples

[0181] The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing the content or the amount used are based on mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography. The analysis conditions for gel permeation chromatography are as follows. Column: TSKgel Multipore HXL-M x 3 + guard column (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 °C Injection volume: 100 μl Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (Agilent 1100 series for LC and Agilent LC / MSD for MASS). In the following examples, the value of this molecular ion peak is indicated as "MASS".

[0182] Synthesis of resin The compounds (monomers) used for the synthesis of resin (A) are shown below. Hereinafter, these compounds are referred to as "monomer (a1-1-3)" etc. according to their formula numbers. TIFF2025081260000137.tif113153

[0183] Synthesis Example 1 [Synthesis of Resin A1] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-1) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-1): monomer (II-1)] was mixed so as to be 34:44:11:11. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed with this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. 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, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. Resin A1 (copolymer) having a weight average molecular weight of about 7.0×10 3 was obtained in a yield of 70%. This resin A1 has the following structural units. TIFF2025081260000138.tif45164

[0184] Synthesis Example 2 [Synthesis of Resin A2] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-16) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-16): monomer (II-1)] was mixed so as to be in a ratio of 34:44:11:11. Further, 1.5 mass times of propylene glycol monomethyl ether was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 mass times that of the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. 3 Resin A2 (copolymer) having a weight average molecular weight of about 6.6×10 was obtained in a yield of 68%. This resin A2 has the following structural units. TIFF2025081260000139.tif47157

[0185] Synthesis Example 3 [Synthesis of Resin A3] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-221) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-221): monomer (II-1)] was mixed at a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether at 1.5 times the mass of the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator at 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Then, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) at 2.0 times the mass of the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. The weight average molecular weight was about 6.9×10 3 Resin A3 (copolymer) with a yield of 73% was obtained. This resin A3 has the following structural units. TIFF2025081260000140.tif48160

[0186] Synthesis Example 4 [Synthesis of Resin A4] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-236) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-236): monomer (II-1)] was mixed at a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether at 1.5 times the mass of the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator at 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Then, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) at 2.0 times the mass of the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery. The weight average molecular weight was about 6.4×10 3Resin A4 (copolymer) was obtained in a yield of 65%. This resin A4 has the following structural units. TIFF2025081260000141.tif57149

[0187] Synthesis Example 5 [Synthesis of Resin A5] As monomers, monomer (a1-4-13), monomer (a1-2-6), monomer (I-s-221), and monomer (II-1) were used, and their molar ratio [monomer (a1-4-13): monomer (a1-2-6): monomer (I-s-221): monomer (II-1)] was mixed at a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether at 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator at 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) at 2.0 times the total mass of all monomers was added to the polymerization reaction solution, and after stirring for 6 hours, it was poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered. As a result, a resin A5 (copolymer) with a weight average molecular weight of about 6.5×10 3 was obtained in a yield of 73%. This resin A5 has the following structural units. TIFF2025081260000142.tif47148

[0188] Synthesis Example 6 [Synthesis of Resin A6] As monomers, monomer (a1-4-19), monomer (a1-2-6), monomer (I-s-221) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-19): monomer (a1-2-6): monomer (I-s-221): monomer (II-1)] was mixed at a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether at 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator at 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) at 2.0 times the total mass of all monomer amounts was added to the polymerization reaction solution, stirred for 6 hours, then poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby a resin A6 (copolymer) having a weight average molecular weight of about 6.2×10 3 was obtained at a yield of 75%. This resin A6 has the following structural units. TIFF2025081260000143.tif46159

[0189] Synthesis Example 7 [Synthesis of Resin A7] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-935) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-935): monomer (II-1)] was mixed at a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether at 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator at 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) at 2.0 times the total mass of all monomer amounts was added to the polymerization reaction solution, stirred for 6 hours, then poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby a resin having a weight average molecular weight of about 5.9×103 Resin A7 (copolymer) represented by the following was obtained in a yield of 68%. This resin A7 has the following structural units. TIFF2025081260000144.tif42164

[0190] Synthesis Example 8 [Synthesis of Resin A8] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-937) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-937): monomer (II-1)] was mixed so as to be in a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed with this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of all monomers was added to the polymerization reaction solution, and after stirring for 6 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby the weight average molecular weight was about 5.8×10 3 Resin A8 (copolymer) represented by the following was obtained in a yield of 77%. This resin A8 has the following structural units. TIFF2025081260000145.tif47159

[0191] Synthesis Example 9 [Synthesis of Resin A9] As monomers, monomer (a1-4-2), monomer (a1-2-6), monomer (I-s-1261) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-1261): monomer (II-1)] was mixed so as to be in a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. 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, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby the weight average molecular weight was about 5.6×10 3 Resin A9 (copolymer) having a yield of 79% was obtained. This resin A9 has the following structural units. TIFF2025081260000146.tif46149

[0192] Synthesis Example 10 [Synthesis of Resin A10] As monomers, monomer (a1-4-2), monomer (a1-6-8), monomer (I-s-1261) and monomer (II-1) were used, and their molar ratio [monomer (a1-4-2): monomer (a1-6-8): monomer (I-s-1261): monomer (II-1)] was mixed so as to be in a ratio of 34:44:11:11. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. 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, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby the weight average molecular weight was about 5.5×103 The resin A10 (copolymer) represented by the following was obtained with a yield of 81%. This resin A10 has the following structural units. TIFF2025081260000147.tif49153

[0193] Synthesis Example 11: Synthesis of Resin AX1 As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (I-s-1) were used and mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (I-s-1)] was 34:55:11. Further, propylene glycol monomethyl ether 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the total mass of all monomers was added to the polymerization reaction solution, and after stirring for 6 hours, it was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered, whereby the weight average molecular weight was about 6.0×10 3 The resin AX1 (copolymer) represented by the following was obtained with a yield of 80%. This resin AX1 has the following structural units. TIFF2025081260000148.tif38141

[0194] Synthesis Example 12: Synthesis of Resin AX2 As monomers, monomer (a1-4-2), monomer (a1-2-6) and monomer (II-1) were used and mixed so that their molar ratio [monomer (a1-4-2): monomer (a1-2-6): monomer (II-1)] was 34:55:11. Further, 1.5 mass times of methyl isobutyl ketone was mixed with this monomer mixture based on the total mass of all monomers. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 mass times the total mass of all monomers was added to the polymerization reaction solution, stirred for 6 hours, and then separated. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was filtered and recovered to obtain resin AX2 (copolymer) having a weight average molecular weight of about 6.0×10 3 and having a yield of 80%. This resin AX2 has the following structural units. TIFF2025081260000149.tif28129

[0195] <Preparation of Resist Composition> As shown in Table 2, the following components were mixed, and the obtained mixture was filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a resist composition.

Table 2

[0196] <Resin> A1 to A10, AX1, AX2: Resin A1 to Resin A10, Resin AX1, Resin AX2 <Acid Generator (B)> B1-25: Salt represented by formula (B1-25); synthesized by the method described in JP-A-2011-126869 TIFF2025081260000151.tif2384<Quencher (C)> C1: Synthesized by the method described in JP-A-2011-39502 TIFF2025081260000152.tif4060 <Solvent> 400 parts of propylene glycol monomethyl ether acetate 300 parts of propylene glycol monomethyl ether 20 parts of γ-butyrolactone

[0197] (Electron Beam Exposure Evaluation of Resist Composition: Alkaline Development) A 6-inch silicon wafer was treated with hexamethyldisilazane on a direct hot plate 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 pre-baked on a direct hot plate at the temperature shown in the "PB" column of Table 2 for 60 seconds to form a composition layer. Using an electron beam lithography machine ["ELS-F125 125 keV" manufactured by Elionix, Inc.], the exposure amount was changed stepwise on the composition layer formed on the wafer, and it was directly drawn so as to form a line and space pattern (pitch 60 nm / line width 30 nm) after development. After exposure, post-exposure baking was performed on a hot plate at the temperature shown in the "PEB" column of Table 2 for 60 seconds. Next, the composition layer on this silicon wafer was paddle-developed at 23 °C for 60 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide as a developer to obtain a resist pattern. The obtained resist pattern (line and space pattern) was observed with a scanning electron microscope, and the exposure amount at which the line width and space width of the line and space pattern with a pitch of 60 nm became 1:1 was defined as the effective sensitivity.

[0198] <Pattern Collapse Resistance Evaluation (PCM) Evaluation> The line width of the line pattern becomes thinner as the exposure amount increases, and pattern disappearance is likely to occur. The numbers indicate the minimum line width (nm) of the resist pattern in which no pattern disappearance due to collapse or peeling is observed in the line pattern formed with an exposure amount equal to or greater than the effective sensitivity. The results are shown in Table 3.

Table 3

Industrial Applicability

[0199] Since the resist composition of the present invention can obtain a resist pattern having good pattern collapse resistance (PCM), it is suitable for semiconductor microfabrication and is extremely useful industrially.

Claims

1. A resist composition comprising a resin that includes a structural unit represented by formula (I), a structural unit having a group represented by formula (II-x), and a structural unit having an acid labile group. [In formula (I), Q 1 and Q. 2 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. R 21 and R 22 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R 21 and R 22 may be the same or different from each other. X 1 represents *-CO-O-, *-O-CO-, *-O-CO-O-, or *-O-, and * represents C(R 21 ) (R 22 ) or C(Q 1 ) (Q 2 ) binding site. L 10 represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. mm1 represents 0 or 1. R 10 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. X 10 represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR ３ -**, *-NR ３ -CO-O-**, *-O-CO-NR ３ -** or *-Ax-Ph-Ay-**. R ３ 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 10 represents the bonding site with the carbon atom to which it is bonded. Z1 ＋ represents an organic cation. [In formula (II-x), Ring W １ represents a heterocycle having 2 to 36 carbon atoms, a hydrogen atom contained in the heterocycle may be substituted with a halogen atom or a hydrocarbon group having 1 to 24 carbon atoms, and —CH ２ - is -O-, -S-, -CO- or -NR ｃ It may be replaced by -. R ｃ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * indicates a binding site.

2. X １０ is a single bond or a group represented by the formula (X １０ -1) ~Formula (X １０ 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 １０ -1) ~ type (X １０ -10) *, ** are binding sites, * is R １０ 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 ３ Represents -. R ３ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

3. L １０ is a single bond, a chain hydrocarbon group having 1 to 10 carbon atoms which may have a substituent (provided that the —CH 2 - may be replaced by -O- or -CO-), a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (provided that the -CH 2 - is -O-, -S-, -CO- or -SO ２ -) or a group formed by combining a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent and a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (with the proviso that -CH 2 - may be replaced by -O- or -CO-, and -CH contained in the cyclic hydrocarbon group 2 - is -O-, -S-, -SO ２ 2. The resist composition according to claim 1, wherein:

4. 2. The resist composition according to claim 1, wherein the structural unit having a group represented by formula (II-x) is a structural unit represented by formula (IIA). [In formula (IIA), Ring W １ has the same meaning as in formula (II-x). 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 Ｘ is a single bond, -A Ｘ１ -* or -CO-O-A Ｘ１ -* (* represents the bonding site with the carbonyl group). A Ｘ１ represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the —CH ２ - is -O-, -CO- or -N(R ｄ ) - may be replaced. R ｄ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

5. The resist composition according to claim 1, wherein the structural unit having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or *-O-(CH 2 ) k1 represents --CO--O--, k1 represents an integer of 1 to 7, and * represents the bonding site with --CO--. R a01 , R a4 and R a5 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 , R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may 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. [In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a6２ , R a63 and R a6４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a6２ and R a63 are bonded to each other to form, together with the carbon atoms to which they are attached, a ring having 3 to 20 carbon atoms. X a61 is a single bond, -CO-O-* or -CO-NR a65 - represents *, * represents a bonding site with Ar, R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 is a single bond, *-O-L a61 - or *-CO-OL a62 -, * represents a bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.

6. 2. The resist composition according to claim 1, wherein the resin further comprises a structural unit represented by formula (a2-A). [In formula (a2-A), R ａ２ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the —CH ２ - is -O-, -CO- or -NR ａ２８ May be replaced with -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ２ represents a single bond or a carbonyl group. nA2 represents an integer of 1 to 5, and when nA2 is 2 or more, the groups in the 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.

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

8. 2. The resist composition according to claim 1, further comprising a salt which generates an acid weaker in acidity than the acid generated from the structural unit represented by formula (I).

9. (1) A step of applying a resist composition according to any one of claims 1 to 8 onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) 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:

10. A resin comprising a structural unit represented by formula (I), a structural unit having a group represented by formula (II-x), and a structural unit having an acid labile group. [In formula (I), Q 1 and Q. 2 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. R 21 and R 22 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R 21 and R 22 may be the same or different from each other. X 1 represents *-CO-O-, *-O-CO-, *-O-CO-O-, or *-O-, and * represents C(R 21 ) (R 22 ) or C(Q 1 ) (Q 2 ) binding site. L 10 represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. mm1 represents 0 or 1. R 10 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. X 10 represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR ３ -**, *-NR ３ -CO-O-**, *-O-CO-NR ３ -** or *-Ax-Ph-Ay-**. R ３ 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 10 represents the bonding site with the carbon atom to which it is bonded. Z1 ＋ represents an organic cation. [In formula (II-x), Ring W １ represents a heterocycle having 2 to 36 carbon atoms, a hydrogen atom contained in the heterocycle may be substituted with a halogen atom or a hydrocarbon group having 1 to 24 carbon atoms, and —CH ２ - is -O-, -S-, -CO- or -NR ｃ It may be replaced by -. R ｃ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * indicates a binding site.

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