Resist composition and method for producing resist pattern

Abstract

To provide a resist composition from which a resist pattern having good line edge roughness can be produced.SOLUTION: There is provided a resist composition comprising an acid generator and one or more resins. At least one of the one or more resins contains a structural unit represented by formula (I), and at least one of the one or more resins contains a structural unit represented by formula (a2-A). [R1 and Ra50 each represent a halogenated alkyl group, an H atom or the like; RA represents a saturated hydrocarbon group; and L12 represents a single bond or an optionally substituted hydrocarbon group.]SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Patent Document 1 describes a resist composition containing a resin containing the following structural unit and an acid generator. TIFF2023118096000001.tif44149 [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-067015 Summary of the Invention [Problem to be solved by the invention]

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

[0005] The present invention includes the following inventions. [1] A resist composition comprising an acid generator and one or more resins, wherein at least one of the one or more resins contains a structural unit represented by formula (I), and at least one of the one or more resins contains a structural unit represented by formula (a2-A). TIFF2023118096000002.tif4088[In formula (I), R 1 represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. R A represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R A are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1, provided that the sum of s1 and t1 is 1 or 2. L 12 represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.] TIFF2023118096000003.tif4552[In formula (a2-A), R a50 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a50 is a single bond or *-X a51 -(A a52 -X a52 ) nb - represents -R a50 represents the bonding site with the carbon atom to which it is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, a plurality of R a51 may be the same or different from each other. [2] The resist composition according to [1], wherein one of the one or more resins contains a structural unit having an acid labile group other than the structural unit represented by formula (I). [3] The resist composition according to [2], wherein the structural unit having an acid labile group other than the structural unit represented by formula (I) includes at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2). TIFF2023118096000004.tif44141 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or -O-(CH2) 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 group combining these. 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. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. [4] The resist composition according to any one of [1] to [3], which contains a resin containing a structural unit represented by the formula (I) and a structural unit represented by the formula (a2-A). [5] The resist composition according to [3], comprising: a resin containing a structural unit represented by formula (I); and a resin containing a structural unit represented by formula (a2-A) and at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2). [6] The resist composition according to [5], wherein the content of the structural unit represented by formula (I) in the resin containing the structural unit represented by formula (I) is 30 to 100 mol % based on all structural units. [7] The resist composition according to [3], which contains a resin containing a structural unit represented by formula (I), a structural unit represented by formula (a2-A), and at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2). [8] The resist composition according to any one of [1] to [7], wherein the acid generator comprises a salt represented by formula (B1). TIFF2023118096000005.tif2862[In formula (B1), Q b1 and Q b2 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. L b1 represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, wherein -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-, and wherein a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted by a fluorine atom or a hydroxy group. Y represents an optionally substituted methyl group or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. Z1 + represents an organic cation. [9] The resist composition according to any one of [1] to [8], further comprising a salt that generates an acid that is weaker in acidity than the acid generated from the acid generator.

[10] (1) A step of applying the resist composition according to any one of [1] to [9] onto a substrate; (2) drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising: [Effects of the Invention]

[0006] By using the resist composition of the present invention, a resist pattern with good line edge roughness (LER) can be produced. DETAILED DESCRIPTION OF THE INVENTION

[0007] In this specification, "(meth)acrylic monomer" means "at least one of an acrylic monomer and a methacrylic monomer." The terms "(meth)acrylate" and "(meth)acrylic acid" have the same meaning. Regarding groups described herein, those that can have either a linear or branched structure are acceptable. When -CH2- in a hydrocarbon group or the like is replaced with -O-, -S-, -CO-, or -SO2-, the same examples apply to each group. A "combined group" refers to a group in which two or more of the exemplified groups are bonded, and the valence of these groups may vary depending on the bonding form. "Derived from" or "derived from" refers to a polymerizable C=C bond in the molecule becoming a single bond (-CC- group) through polymerization. When stereoisomers exist, all stereoisomers are included. In this specification, the term "solid content of the resist composition" refers to the sum of all components in the resist composition excluding the solvent (E), which will be described later.

[0008] [Resist Composition] The resist composition of the present invention contains one or more resins (hereinafter sometimes referred to as "resin component (A)" or "resin (A)") and an acid generator (hereinafter sometimes referred to as "acid generator (B)"). Of the one or more resins, at least one resin contains a structural unit represented by formula (I) (hereinafter sometimes referred to as "structural unit (I)"), and of the one or more resins, at least one resin contains a structural unit represented by formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). For example, the same resin may contain both the "structural unit (I)" and the "structural unit (a2-A)," or the resin containing the "structural unit (I)" and the resin containing the "structural unit (a2-A)" may be different resins. The resist composition of the present invention preferably contains a quencher such as a salt that generates an acid with a weaker acidity than the acid generated from the acid generator (hereinafter may be referred to as "quencher (C)"), and preferably contains a solvent (hereinafter may be referred to as "solvent (E)").

[0009] <Resin component (A)> Each structural unit contained in one or more resins contained in the resin component (A) will be described below. <Structural Unit (I)> At least one resin among the one or more resins contained in the resist composition of the present invention contains a structural unit represented by formula (I) (structural unit (I)). The resin containing the structural unit (I) may be a resin containing a structural unit represented by formula (a2-A), or may not contain a structural unit represented by formula (a2-A). For example, the resin containing the structural unit (I) may be a resin containing a structural unit represented by formula (I) and a structural unit represented by formula (a2-A), a resin containing a structural unit represented by formula (I) and a structural unit having an acid labile group other than the structural unit represented by formula (I), or a resin containing a structural unit represented by formula (I), a structural unit represented by formula (a2-A), and a structural unit having an acid labile group other than the structural unit represented by formula (I). The resin containing the structural unit represented by formula (I) may further contain structural units other than those described above. The structural unit (I) is represented by the following formula: TIFF2023118096000006.tif3988 [In formula (I), all symbols have the same meanings as defined above.]

[0010] In formula (I), R 1 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, an n-pentyl group, and an n-hexyl group, and are preferably alkyl groups having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group. R 1 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 1 Examples of the alkyl group having a halogen atom include a difluoromethyl group, 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 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a 2,2,3,3,3-pentafluoropropyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perchloromethyl group, a perbromomethyl group, and a periodomethyl group. R 1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0011] L 12 Examples of the hydrocarbon group having 1 to 36 carbon atoms include aliphatic hydrocarbon groups (chain hydrocarbon groups such as alkanediyl groups, alkenediyl groups, and alkynediyl groups, and monocyclic or polycyclic alicyclic hydrocarbon groups), aromatic hydrocarbon groups, and the like, and may also be hydrocarbon groups formed by combining two or more of these groups. 12The —CH 2 — contained in the hydrocarbon group in the formula (I) may be replaced by —O—, —S—, —CO— or —SO 2 —. 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, and a dodecane-1,12-diyl group; Branched alkanediyl groups such as ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. Examples include: 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, and a nonynediyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 24, more preferably 1 to 18, even more preferably 1 to 12, still more preferably 1 to 9, even more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3.

[0012] Examples of the alkanediyl group in which -CH2- is replaced by -O-, -S-, -CO-, or -SO2- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), and - is replaced with -S-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -CO-), alkylsulfonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -SO2-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -CO-O-), oxy group (a group in which -CH2-CH2- at any position in a methylene group is replaced with -CO-O-), a carbonyl group (a group in which a -CH2- in a methylene group is replaced with -CO-), a thio group (a group in which a -CH2- in a methylene group is replaced with -S-), a sulfonyl group (a group in which a -CH2- in a methylene group is replaced with -SO2-), an alkanediyloxy group (a group in which a -CH2- in any position in an alkanediyl group is replaced with -O-), an alkanediyloxycarbonyl group (a group in which a -CH2-CH2- in any position in an alkanediyl group is replaced with -O-CO- substituted with -CO-), an alkanediylcarbonyl group (an alkanediyl group in which -CH- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH-CH- at any position is replaced with -CO-O-), an alkanediylthio group (an alkanediyl group in which -CH- at any position is replaced with -S-), and an alkanediylsulfonyl group (an alkanediyl group in which -CH- at any position is replaced with -SO-). Examples of the alkoxy group include alkoxy groups having 1 to 35 carbon atoms, such as a methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, undecyloxy group, etc. The number of carbon atoms in the alkoxy group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkylthio group include alkylthio groups having 1 to 35 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, etc. The number of carbon atoms in the alkylthio group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. The alkoxycarbonyl group, alkylcarbonyl group and alkylcarbonyloxy group represent groups in which a carbonyl group or carbonyloxy group is bonded to the above-mentioned alkyl group or alkoxy group. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 35 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 36 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 35 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The alkylcarbonyloxy group preferably has 2 to 11 carbon atoms, more preferably 2 to 6 carbon atoms, even more preferably 2 to 4 carbon atoms, and even more preferably 2 or 3 carbon atoms. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 35 carbon atoms, such as a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, etc. The number of carbon atoms in the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediyloxy group include alkanediyloxy groups having 1 to 35 carbon atoms, such as a methyleneoxy group, an ethyleneoxy group, a propanediyloxy group, a butanediyloxy group, a pentanediyloxy group, a hexanediyloxy group, an octanediyloxy group, a 2-ethylhexanediyloxy group, a nonanediyloxy group, a decanediyloxy group, an undecanediyloxy group, etc. The number of carbon atoms in the alkanediyloxy group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyloxycarbonyl group include alkanediyloxycarbonyl groups having 2 to 35 carbon atoms, such as a methyleneoxycarbonyl group, an ethyleneoxycarbonyl group, a propanediyloxycarbonyl group, a butanediyloxycarbonyl group, a pentanediyloxycarbonyl group, a hexanediyloxycarbonyl group, an octanediyloxycarbonyl group, a 2-ethylhexanediyloxycarbonyl group, a nonanediyloxycarbonyl group, a decanediyloxycarbonyl group, an undecanediyloxycarbonyl group, etc. The number of carbon atoms in the alkanediyloxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 36 carbon atoms, such as a methylenecarbonyl group, an ethylenecarbonyl group, a propanediylcarbonyl group, a butanediylcarbonyl group, a pentanediylcarbonyl group, a hexanediylcarbonyl group, an octanediylcarbonyl group, a 2-ethylhexanediylcarbonyl group, a nonanediylcarbonyl group, a decanediylcarbonyl group, an undecanediylcarbonyl group, etc. The number of carbon atoms in the alkanediylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 35 carbon atoms, such as a methylenecarbonyloxy group, an ethylenecarbonyloxy group, a propanediylcarbonyloxy group, a butanediylcarbonyloxy group, a pentanediylcarbonyloxy group, a hexanediylcarbonyloxy group, an octanediylcarbonyloxy group, a 2-ethylhexanediylcarbonyloxy group, a nonanediylcarbonyloxy group, a decanediylcarbonyloxy group, an undecanediylcarbonyloxy group, etc. The number of carbon atoms in the alkanediylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediylthio group include alkanediylthio groups having 1 to 35 carbon atoms, such as a methylenethio group, an ethylenethio group, a propanediylthio group, a butanediylthio group, a pentanediylthio group, a hexanediylthio group, a heptanediylthio group, an octanediylthio group, a nonanediylthio group, a decanediylthio group, an undecanediylthio group, a dodecanediylthio group, and a 2-methylpropanediylthio group. The number of carbon atoms in the alkanediylthio group is preferably 1 to 11, 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 a methylenesulfonyl group, an ethylenesulfonyl group, a propylenesulfonyl group, etc. The number of carbon atoms in the alkanediylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. The substitutions in the alkenediyl group and alkynediyl group may include a carbon-carbon double bond or a carbon-carbon triple bond at any position in the above-mentioned examples of substitutions in the alkanediyl group.

[0013] The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples thereof include the groups shown below: The bonding site may be at any position. TIFF2023118096000007.tif46168Specifically, monocyclic alicyclic hydrocarbon groups include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, cyclohexene-3,6-diyl, and cyclooctane-1,5-diyl; and polycyclic alicyclic hydrocarbon groups include polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, 5-norbornene-2,3-diyl, adamantane-1,5-diyl, and adamantane-2,6-diyl. The alicyclic hydrocarbon group preferably has 3 to 24 carbon atoms, more preferably 3 to 18 carbon atoms, even more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. Examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O-, -S-, -CO-, or -SO2- include the groups shown below. Also included are groups in which, among the groups shown below, -O- is replaced with -S- and -CO- is replaced with -SO2-. The bonding site can be at any position. TIFF2023118096000008.tif47169 Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, etc. The aromatic hydrocarbon group preferably has 6 to 24 carbon atoms, more preferably 6 to 18 carbon atoms, even more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. When a -CH2- in a hydrocarbon group is replaced with -O-, -S-, -CO-, or -SO2-, the total number of carbon atoms in the hydrocarbon group is the number of carbon atoms before the replacement, which may be one or more.

[0014] Examples of hydrocarbon groups that combine two or more groups include groups that combine a chain hydrocarbon group such as an alkanediyl group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group, and the combination may include two or more types of each of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group. Examples include -alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-aromatic hydrocarbon group-, and -aromatic hydrocarbon group-alkanediyl group-. Any of the groups may be bonded to an oxygen atom.

[0015] L 12 The substituents on the hydrocarbon group include halogen atoms and cyano groups. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L 12 The hydrocarbon group of the formula (I) is a group in which -CH2- is replaced by -O- or -CO-. 12 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, or an alkylcarbonyloxy group. L 12 The hydrocarbon group in may have one or more substituents.

[0016] L 12is preferably a single bond, a chain hydrocarbon group having 1 to 8 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-), or a group in which a chain hydrocarbon group having 1 to 8 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are combined (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-), and is preferably an alkanediyl group having 1 to 6 carbon atoms or an alkanediyl group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 3 to 12 carbon atoms. groups (wherein —CH2— contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced by —O—, —S—, —SO2—, or —CO—), is more preferred, a group combining an alkanediyl group having 1 to 3 carbon atoms or an alkanediyl group having 1 to 5 carbon atoms with an alicyclic hydrocarbon group having 3 to 12 carbon atoms (wherein —CH2— contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced by —O— or —CO—), and even more preferred is a methylene group, an adamantanediyl group -O—CO—O—CH2—, a norbornanelactonediyl group -CO—O—CH2—, or a cyclohexanediyl group -O—CO—O—CH2—.

[0017] The group represented by the following formula is a group represented by formula (IC). TIFF2023118096000009.tif2982 [In formula (IC), all symbols have the same meanings as defined above.] s1 is preferably 1, t1 is preferably 1, and the sum of s1 and t1 is preferably 2. The group represented by formula (IC) is preferably a group represented by the following formula: TIFF2023118096000010.tif2599 [wherein all symbols have the same meaning as in formula (IC)]

[0018] In the group represented by formula (IC), u1 is 1 and RA L 12 The group bonded to the carbon atom adjacent to is represented by the following formula (IC-1). TIFF2023118096000011.tif3174 [In formula (IC-1), all symbols have the same meaning as in formula (IC)] R A Examples of the saturated hydrocarbon group include chain saturated hydrocarbon groups such as alkyl groups, alicyclic saturated hydrocarbon groups, and groups in which two or more of these groups are combined. R A Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, etc. The number of carbon atoms in the chain saturated hydrocarbon group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. The alicyclic saturated hydrocarbon group may be any of monocyclic, polycyclic, and spirocyclic. Examples of the alicyclic saturated hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl, and polycyclic cycloalkyl groups such as norbornyl and adamantyl. The number of carbon atoms in the alicyclic saturated hydrocarbon group is preferably 3 to 10, more preferably 3 to 8, and even more preferably 3 to 6. The combined group may be a group in which one alkyl group and one alicyclic saturated hydrocarbon group are combined, or a group in which two or more of either or two or more of both are combined.

[0019] Examples of the structural unit (I) include the following structural units. TIFF2023118096000012.tif130165

[0020] In the structural units represented by formulas (I-1) to (I-11), R 1Specific examples of the structural unit (I) include structural units in which a methyl group corresponding to the following formula is replaced with a hydrogen atom. Among these, structural units represented by formulas (I-1) to (I-4) and (I-9) are preferred, structural units represented by formulas (I-1), (I-4) and (I-9) are more preferred, and structural units represented by formulas (I-1) and (I-9) are even more preferred. In the case of a resin containing at least the structural unit (I), the content of the structural unit (I) relative to all structural units in the resin is 1 mol% or more, preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more. It can also be 100 mol% or less. Specifically, it can be 1 to 100 mol%, preferably 5 to 100 mol%, more preferably 10 to 100 mol%, and even more preferably 15 to 100 mol%.

[0021] <Structural unit (a2-A)> At least one resin among the one or more resins contained in the resist composition of the present invention contains a structural unit represented by formula (a2-A) (structural unit (a2-A)). The resin containing the structural unit (a2-A) may be a resin containing a structural unit represented by formula (I), or may not contain a structural unit represented by formula (I). For example, the resin containing the structural unit (a2-A) may be a resin containing a structural unit represented by formula (a2-A) and a structural unit represented by formula (I), a resin containing a structural unit represented by formula (a2-A) and a structural unit having an acid labile group other than the structural unit represented by formula (I), or a resin containing a structural unit represented by formula (a2-A), a structural unit represented by formula (I), and a structural unit having an acid labile group other than the structural unit represented by formula (I). The resin containing the structural unit represented by formula (a2-A) may further contain structural units other than those described above. The structural unit (a2-A) is represented by the following formula: TIFF2023118096000013.tif4955[In formula (a2-A), R a50 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a50 is a single bond or *-X a51 -(A a52 -X a52 ) nb - represents -R a50 represents the bonding site with the carbon atom to which it is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, a plurality of R a51 may be the same or different from each other.

[0022] R a50 and R a51 Examples of the halogen atom in the formula include a fluorine atom, a chlorine atom, and a bromine atom. R a50 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) 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, and a perfluorohexyl group. R a50is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a51 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a51 Examples of the alkoxy group in 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 an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a51 Examples of the alkoxyalkyl group in the formula (I) include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a51 Examples of the alkoxyalkoxy group in include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. R a51 Examples of the alkylcarbonyl group in the formula (I) include an acetyl group, a propionyl group, a butyryl group, etc. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a51Examples of the alkylcarbonyloxy group in the formula (I) include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a51 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0023] *-X a51 -(A a52 -X a52 ) nb -Examples include *-O-, *-CO-O-, *-O-CO-, *-CO-OA a52 -CO-O-, *-O-CO-A a52 -O-, *-OA a52 -CO-O-, *-CO-OA a52 -O-CO-, *-O-CO-A a52 -O-CO-, and *-CO-O- and *-CO-OA are particularly mentioned. a52 -CO-O- or *-OA a52 -CO-O- is preferred.

[0024] A a52 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A a52 is preferably a methylene group or an ethylene group.

[0025] Aa50 is a single bond, *-CO-O- or *-CO-OA a52 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0026] mb is preferably 0, 1 or 2, and more preferably 0 or 1. At least one hydroxy group is preferably bonded to the meta or para position of the benzene ring, and when the phenyl group has two or more hydroxy groups, the two hydroxy groups are preferably bonded to the meta and para positions, respectively.

[0027] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A Nos. 2010-204634 and 2012-12577. The structural unit (a2-A) includes structural units represented by formulae (a2-2-1) to (a2-2-24) and R in the structural unit (a2-A) in the structural units represented by formulae (a2-2-1) to (a2-2-24). a50 The structural unit (a2-A) includes structural units represented by formulas (a2-2-1) to (a2-2-4), structural units represented by formula (a2-2-6), structural units represented by formula (a2-2-8), structural units represented by formulas (a2-2-12) to (a2-2-18), and structural units represented by formulas (a2-2-1) to (a2-2-4), structural units represented by formula (a2-2-6), structural units represented by formula (a2-2-8), and structural units represented by formulas (a2-2-12) to (a2-2-18), in which R in the structural unit (a2-A) is a50In the structural unit represented by formula (a2-2-3), the structural unit represented by formula (a2-2-4), the structural unit represented by formula (a2-2-8), the structural unit represented by formula (a2-2-12) to formula (a2-2-14), the structural unit represented by formula (a2-2-18), and the structural unit represented by formula (a2-2-3), the structural unit represented by formula (a2-2-4), the structural unit represented by formula (a2-2-8), the structural unit represented by formula (a2-2-12) to formula (a2-2-14), and the structural unit represented by formula (a2-2-18), a50 In the structural unit represented by formula (a2-2-3), the structural unit represented by formula (a2-2-4), the structural unit represented by formula (a2-2-8), and the structural unit represented by formula (a2-2-3), the structural unit represented by formula (a2-2-4), and the structural unit represented by formula (a2-2-8), a50 More preferably, the structural unit is a structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom: TIFF2023118096000014.tif79169

[0028] In the case of a resin containing at least the structural unit (a2-A), the content of the structural unit (a2-A) relative to all structural units in the resin can be 1 mol% or more, preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and even more preferably 20 mol% or more. It can also be 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it can be 1 to 100 mol%, preferably 5 to 80 mol%, more preferably 10 to 70 mol%, even more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%.

[0029] <Structural Unit Having an Acid Labile Group Other than the Structural Unit Represented by Formula (I)> One of the one or more resins contained in the resist composition of the present invention may contain a structural unit having an acid labile group other than the structural unit represented by formula (I) (hereinafter, sometimes referred to as "structural unit (a1)"). The resin containing this structural unit (a1) may not contain the structural unit (I) or the structural unit (a2-A). In particular, the resin containing the structural unit (a1) preferably does not contain the structural unit (I) but contains the structural unit (a2-A). Here, the acid labile group refers to a group that has a leaving group and that is released upon contact with an acid to form a hydrophilic group (e.g., a hydroxy group or a carboxy group).

[0030] <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 is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF2023118096000015.tif2298[In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining any of these; or R a1 and R a2 are bonded to each other to form, together with the carbon atoms to which they are bonded, an alicyclic hydrocarbon group having 3 to 20 carbon atoms. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * denotes a binding site.] TIFF2023118096000016.tif2278[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; 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, together with the carbon atom to which they are bonded and X, a heterocyclic group having 3 to 20 carbon atoms, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced with -O- or -S-. X represents an oxygen atom or a sulfur atom. na' represents 0 or 1. * denotes a binding site.]

[0031] R a1 , R a2 and R a3 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, a heptyl group, and an octyl group. R a1 , R a2 and R a3 Examples of the alkenyl group in the formula (I) include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl groups. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms. TIFF2023118096000017.tif10159R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, or a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, or the like), and an aryl-cycloalkyl group such as a phenylcyclohexyl group. Preferably, ma is 0 and na is 1. R a1 and R a2 -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 with -O-. TIFF2023118096000018.tif30138

[0032] R a1’ , R a2’ and R a3’ Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups and combination groups are R a1 , R a2 and R a3 Examples of the groups include the same as those listed in the above. R a2’ and R a3’ When they are bonded to each other to form a heterocyclic group together with the carbon atoms to which they are bonded and X, -C(R a1’ )(R a2’ )-XR a3’Examples of the groups include the following: * represents a binding site. TIFF2023118096000019.tif19124R a1’ and R a2’ At least one of these is preferably a hydrogen atom. na' is preferably 0.

[0033] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 is an alkyl group, ma=0, and na=1. The group is preferably a tert-butoxycarbonyl group. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, and R a3 is an alkyl group, ma=0, and na=1. In formula (1), R a1 and R a2 are each independently an alkyl group, and R a3 is an adamantyl group, ma=0, and na=1. Specific examples of the group (1) include the following: * represents a binding site. TIFF2023118096000020.tif130165

[0034] Specific examples of group (2) include the following groups: * represents a binding site. TIFF2023118096000021.tif55153

[0035] 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.

[0036] Of the (meth)acrylic monomers having an acid labile group, preferred are those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms. When 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 a resist composition, the resolution of the resist pattern can be improved.

[0037] The structural unit derived from a (meth)acrylic monomer having group (1) is preferably 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, at least one structural unit selected from the group consisting of structural unit (a1-0), structural unit (a1-1), and structural unit (a1-2) is used, and more preferably, at least one or two structural units selected from the group consisting of structural unit (a1-1) and structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2023118096000022.tif47154 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or -O-(CH2) 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 group combining these. R a6 and Ra7 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. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

[0038] R a01 , R a4 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—(CH2) k01 It is —CO—O— (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a7 The alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group and combinations thereof in the formula (1) include R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a02 , R a03 , and R a04 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a6 and R a7 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group, or a t-butyl group, and even more preferably an ethyl group, an isopropyl group, or a t-butyl group. R a6 and R a7The alkenyl group in the formula (I) is preferably an alkenyl group having 2 to 6 carbon atoms, and more preferably an ethenyl group, a propenyl group, an isopropenyl group, or a butenyl group. R a02 , R a03 , R a04 , R a6 and R a7 The alicyclic hydrocarbon group preferably has 5 to 12 carbon atoms, and more preferably 5 to 10 carbon atoms. R a02 , R a03 , R a04 , R a6 and R a7 The aromatic hydrocarbon group preferably has 6 to 12 carbon atoms, and more preferably 6 to 10 carbon atoms. In the group in which an alkyl group and an alicyclic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the alicyclic hydrocarbon group is preferably 18 or less. In the group in which an alkyl group and an aromatic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the aromatic hydrocarbon group is preferably 18 or less. R a02 and R a03 is preferably an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, and more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group. R a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, and more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an aromatic hydrocarbon group having 6 to 12 carbon atoms, 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, and even more preferably an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, or a phenyl group. m1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1' is preferably 0 or 1.

[0039] Examples of the structural unit (a1-0) include structural units represented by any one of formulas (a1-0-1) to (a1-0-18) and R a01 and structural units in which the methyl group corresponding to the formula (a1-0-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group (an alkyl group having a halogen atom) or another alkyl group, and structural units represented by any of formulas (a1-0-1) to (a1-0-10), (a1-0-13) and (a1-0-14) are preferred. TIFF2023118096000023.tif95156

[0040] Examples of the structural unit (a1-1) include structural units derived from monomers described in JP-A-2010-204646. Among these, structural units represented by any one of formulas (a1-1-1) to (a1-1-7) and R in the structural unit (a1-1) are preferred. a4 A structural unit in which the methyl group corresponding to the formula (a1-1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group is preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF2023118096000024.tif38164

[0041] The structural unit (a1-2) includes a structural unit represented by any one of formulas (a1-2-1) to (a1-2-14) and R a5 and structural units in which the methyl group corresponding to the formula (a1-2-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group, and structural units represented by any of formulas (a1-2-2), (a1-2-5), (a1-2-6), and (a1-2-10) to (a1-2-14) are preferred. TIFF2023118096000025.tif60163

[0042] When the resin contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these, based on the total structural units of the resin, can be 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, and even more preferably 30 mol% or more. Alternatively, the total content can be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, and even more preferably 70 mol% or less. Specifically, the total content can be 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, even more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin contains the structural unit (a1-0), the content thereof is 5 mol% or more, preferably 10 mol% or more, based on the total structural units of the resin. Also, the content is 80 mol% or less, preferably 75 mol% or less, and more preferably 70 mol% or less. Specifically, the content is 5 to 80 mol%, preferably 5 to 75 mol%, and more preferably 10 to 70 mol%. When the resin contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these units relative to all structural units in the resin is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, and even more preferably 30 mol% or more. Also, the total content may be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, still more preferably 75 mol% or less, and even more preferably 70 mol% or less. Specifically, the total content is 10 to 90 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, even more preferably 20 to 80 mol%, even more preferably 20 to 75 mol%, and even more preferably 20 to 70 mol%.

[0043] An example of the structural unit (a1) having the group (2) is a structural unit represented by formula (a1-4) (hereinafter, sometimes referred to as "structural unit (a1-4)"). TIFF2023118096000026.tif4868[In formula (a1-4), R a32 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a33 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a30 is a single bond or *-X a31 -(A a32 -X a32 ) nc - represents -R a32 represents the bonding site with the carbon atom to which it is bonded. A a32 represents an alkanediyl group having 1 to 6 carbon atoms. X a31 and X a32 each independently represents -O-, -CO-O- or -O-CO-. nc represents 0 or 1. la represents an integer of 0 to 4. When la is an integer of 2 or more, a plurality of R a33 may be the same or different from each other. 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, together with the -CO- to which they are bonded, a divalent hydrocarbon group having 2 to 20 carbon atoms, and the hydrocarbon group and the -CH2- contained in the divalent hydrocarbon group may be replaced with -O- or -S-.]

[0044] R a32 and R a33 Examples of the halogen atom in the formula include a fluorine atom, a chlorine atom, and a bromine atom. R a32 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) 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, and a perfluorohexyl group. R a32 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a33 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a33 Examples of the alkoxy group in include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a33Examples of the alkoxyalkyl group in the formula (I) include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a33 Examples of the alkoxyalkoxy group in include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. R a33 Examples of the alkylcarbonyl group in the formula (I) include an acetyl group, a propionyl group, a butyryl group, etc. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a33 Examples of the alkylcarbonyloxy group in the formula (I) include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a33 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0045] *-X a31 -(A a32 -X a32 ) nc-Examples include *-O-, *-CO-O-, *-O-CO-, *-CO-OA a32 -CO-O-, *-O-CO-A a32 -O-, *-OA a32 -CO-O-, *-CO-OA a32 -O-CO-, *-O-CO-A a32 -O-CO-, and *-CO-O- and *-CO-OA are particularly mentioned. a32 -CO-O- or *-OA a32 -CO-O- is preferred.

[0046] A a32 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A a32 is preferably a methylene group or an ethylene group.

[0047] A a30 is a single bond, *-CO-O- or *-CO-OA a32 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0048] la is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. R a34 , R a35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which these groups are combined. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): TIFF2023118096000027.tif10151 Examples of aromatic hydrocarbon groups include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, or a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, or the like), and an aryl-cycloalkyl group such as a phenylcyclohexyl group. In particular, R a36 Examples of the group 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.

[0049] 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 a36The hydrocarbon group in R 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. a36 The alkyl group and alicyclic hydrocarbon group in R are preferably unsubstituted. a36 The aromatic hydrocarbon group in is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0050] -OC(R a34 )(R a35 )-OR a36 is eliminated on contact with an acid (e.g., p-toluenesulfonic acid) to form a hydroxy group. -OC(R a34 )(R a35 )-OR a36 is preferably bonded to the m-position or p-position of the benzene ring, and more preferably to the p-position.

[0051] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferred are structural units represented by formulas (a1-4-1) to (a1-4-24) and R in the structural unit (a1-4). a32 and more preferably, the structural units represented by formulae (a1-4-1) to (a1-4-5), (a1-4-10), (a1-4-13), (a1-4-14), (a1-4-19), and (a1-4-20). TIFF2023118096000028.tif134169

[0052] When the resin contains the structural unit (a1-4), the content thereof is preferably 10 to 95 mol %, more preferably 15 to 90 mol %, even more preferably 20 to 85 mol %, even more preferably 20 to 70 mol %, and particularly preferably 20 to 60 mol %, based on the total amount of all structural units in the resin.

[0053] Examples of the structural unit derived from a (meth)acrylic monomer having the group (2) include a structural unit represented by formula (a1-5) (hereinafter, sometimes referred to as "structural unit (a1-5)"). TIFF2023118096000029.tif4253[In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. Z a1 is a single bond or -(CH2) 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.

[0054] Examples of halogen atoms include fluorine atoms and chlorine atoms, with fluorine atoms being preferred. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a fluoromethyl group, and a trifluoromethyl group. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. L 51 is preferably an oxygen atom. L52 and L 53 Among these, it is preferred that one is —O— and the other is —S—. s1 is preferably 1. s1' is preferably an integer of 0 to 2. Z a1 is preferably a single bond or —CH2—CO—O—.

[0055] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among these, the structural units represented by formulas (a1-5-1) to (a1-5-4) are preferred, and the structural unit represented by formula (a1-5-1) or (a1-5-2) is more preferred. TIFF2023118096000030.tif31130

[0056] When the resin contains the structural unit (a1-5), the content thereof is preferably 1 to 50 mol %, more preferably 3 to 45 mol %, even more preferably 5 to 40 mol %, and even more preferably 5 to 30 mol %, based on all structural units in the resin.

[0057] Further, examples of the structural unit (a1) include the following structural units. TIFF2023118096000031.tif27161

[0058] When the resin contains structural units such as (a1-3-1) to (a1-3-7), the content thereof is preferably 10 to 95 mol %, more preferably 15 to 90 mol %, even more preferably 20 to 85 mol %, even more preferably 20 to 70 mol %, and particularly preferably 20 to 60 mol %, based on the total structural units of the resin.

[0059] <Other structural units> Of the one or more resins contained in resin component (A), one resin may contain a structural unit having a hydroxy group but not an acid labile group (hereinafter, sometimes referred to as "structural unit (a2)"), a structural unit having a lactone ring but not an acid labile group (hereinafter, sometimes referred to as "structural unit (a3)"), a structural unit other than a structural unit having an acid labile group and having a halogen atom (hereinafter, sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group (hereinafter, sometimes referred to as "structural unit (a5)"), a structural unit having an -SO2- group (hereinafter, sometimes referred to as "structural unit (a6)"), a structural unit that decomposes upon exposure to generate acid (hereinafter, sometimes referred to as "structural unit (II)"), or other structural units derived from monomers having no acid labile groups known in the resist field. By using a resin having the structural unit (a2) or the structural unit (a3) ​​in the resist composition of the present invention, it is possible to improve the resolution of the resist pattern and the adhesion to the substrate.

[0060] <Structural unit (a2)> The hydroxy group contained in the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group. When producing a resist pattern from the resist composition of the present invention, if a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) is used as an exposure light source, the structural unit (a2) preferably has a phenolic hydroxy group, and more preferably the structural unit (a2-A) described above. Furthermore, if an ArF excimer laser (193 nm) or the like is used, the structural unit (a2) preferably has an alcoholic hydroxy group, and more preferably the structural unit (a2-1) described below. The structural unit (a2) may contain one type alone or two or more types.

[0061] An example of the structural unit (a2) having an alcoholic hydroxy group is a structural unit represented by formula (a2-1) (hereinafter, sometimes referred to as "structural unit (a2-1)"). TIFF2023118096000032.tif4562[In formula (a2-1), L a3 is -O- or *-O-(CH2) k2 represents -CO-O-, k2 represents an integer of 1 to 7. * represents the bonding site with —CO—. R a14 represents a hydrogen atom or a methyl group. R a15 and R a16 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. o1 represents an integer between 0 and 10.

[0062] In equation (a2-1), L a3 is preferably -O-, -O-(CH2) f1 It is —CO—O— (wherein f1 represents an integer of 1 to 4), and more preferably —O—. R a14 is preferably a methyl group. R a15 is preferably a hydrogen atom. R a16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of 0 to 3, and more preferably 0 or 1.

[0063] Examples of the structural unit (a2-1) include structural units derived from monomers described in JP 2010-204646 A. A structural unit represented by any one of formulas (a2-1-1) to (a2-1-6) is preferred, a structural unit represented by any one of formulas (a2-1-1) to (a2-1-4) is more preferred, and a structural unit represented by formula (a2-1-1) or formula (a2-1-3) is even more preferred. TIFF2023118096000033.tif53147

[0064] When the resin contains the structural unit (a2-1), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on the total structural units of the resin. It may also be 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and even more preferably 10 mol% or less. Specifically, it may be 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and even more preferably 1 to 10 mol%.

[0065] <Structural unit (a3)> The lactone ring contained in the structural unit (a3) ​​may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring with another ring. Preferred examples include 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)).

[0066] The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3), or formula (a3-4). One of these may be contained alone, or two or more may be contained. TIFF2023118096000034.tif50161 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6 are each independently -O- or -O-(CH2) k3 It represents a group represented by —CO—O— (k3 represents an integer of 1 to 7). L a7 -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OL a9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. La8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates 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 -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , R a23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3. w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same as or different from each other.

[0067] R a21 , R a22 , R a23 and R a25 Examples of the aliphatic hydrocarbon group in include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom in the formula include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a18 , R a19 , Ra20 and R a24 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group, and preferably an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group or an ethyl group. R a18 , R a19 , R a20 and R a24 Examples of the alkyl group having a halogen atom in the formula (I) 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. L a8 and L a9 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group.

[0068] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or -O-(CH2) k3 In -CO-O-, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and even more preferably an oxygen atom. R a18 ~R a21 is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group, or a methyl group. p1, q1 and r1 each independently represent preferably an integer of 0 to 2, and more preferably 0 or 1.

[0069] In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH 2 —CO—O— or —O—C 2 H 4 —CO—O—. w1 is preferably an integer of 0 to 2, and more preferably 0 or 1. In particular, the formula (a3-4) is preferably the formula (a3-4)'. TIFF2023118096000035.tif4051 (in the formula, R a24 , L a7 has the same meaning as above.)

[0070] Examples of the structural unit (a3) ​​include structural units derived from monomers described in JP 2010-204646 A, JP 2000-122294 A, and JP 2012-41274 A. Examples of the structural unit (a3) ​​include structural units represented by any of formulas (a3-1-1), (a3-1-2), (a3-2-1), (a3-2-2), (a3-3-1), (a3-3-2), and (a3-4-1) to (a3-4-12), and in the structural units, R in formulas (a3-1) to (a3-4) a18 , R a19 , R a20 and R a24 A structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom is preferred.

[0071] JPEG2023118096000036.jpg115165

[0072] When the resin contains the structural unit (a3), the total content thereof, based on all structural units in the resin, can be 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more. It can also be 70 mol% or less, preferably 65 mol% or less, and more preferably 60 mol% or less. Specifically, it can be 1 to 70 mol%, preferably 3 to 65 mol%, and more preferably 5 to 60 mol%. The content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3), or the structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, and even more preferably 5 mol% or more, based on the total structural units of the resin. It is also preferably 60 mol% or less, more preferably 55 mol% or less, and even more preferably 50 mol% or less. Specifically, it is preferably 1 to 60 mol%, more preferably 3 to 55 mol%, and even more preferably 5 to 50 mol%.

[0073] <Structural unit (a4)> Examples of the structural unit (a4) include the following structural units. TIFF2023118096000037.tif3066[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having 1 to 24 carbon atoms and containing a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.] R 42 Examples of the saturated hydrocarbon group represented by the formula (I) include chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups.

[0074] Examples of the chain hydrocarbon group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups; decahydronaphthyl, adamantyl, norbornyl, and polycyclic alicyclic hydrocarbon groups such as the following groups (* indicates a bonding site): TIFF2023118096000038.tif11159 Examples of groups formed by combination include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic hydrocarbon group-alkyl group.

[0075] The structural unit (a4) includes at least one structural unit selected from the group consisting of formula (a4-0), formula (a4-1), formula (a4-2), formula (a4-3) and formula (a4-4). TIFF2023118096000039.tif4652[In formula (a4-0), R 5 represents a hydrogen atom or a methyl group. L 4a represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 4 carbon atoms. L 3a represents a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms. R 6 represents a hydrogen atom or a fluorine atom.

[0076] L 4aExamples of the divalent aliphatic saturated hydrocarbon group in the formula (I) 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. L 3a Examples of the perfluoroalkanediyl group in the formula (I) include a difluoromethylene group, a perfluoroethylene group, a perfluoropropane-1,1-diyl 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, perfluorohexane-1,6-diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1,7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3,3-diyl group, and perfluorooctane-4,4-diyl group. L 3a Examples of the perfluorocycloalkanediyl group in the formula (I) include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, and a perfluoroadamantanediyl group.

[0077] L 4a is preferably a single bond, a methylene group, or an ethylene group, and more preferably a single bond or a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0078] The structural unit (a4-0) includes the structural units shown below and R in the structural unit (a4-0) in the structural units shown below. 5 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2023118096000040.tif97165

[0079] Examples of the structural unit (a4) include a structural unit represented by formula (a4-1). TIFF2023118096000041.tif4670[In formula (a4-1), R a41 represents a hydrogen atom or a methyl group. R a42 represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. A a41 represents an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a group represented by formula (a-g1), a41 and R a42 At least one of the groups has a halogen atom (preferably a fluorine atom) as a substituent. TIFF2023118096000042.tif1384 [In formula (a-g1), s represents 0 or 1. A a42 and A a44 each independently represents a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. A a43 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. X a41 and X a42 each independently represents -O-, -CO-, -CO-O- or -O-CO-. However, A a42 , A a43 , A a44 , X a41 and X a42The total number of carbon atoms is 7 or less. * indicates the binding site, and the * on the right is -O-CO-R a42 ]

[0080] R a42 Examples of the saturated hydrocarbon group in include a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and groups formed by combining these groups. Examples of the chain saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group. Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic saturated hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* indicates a bonding site): TIFF2023118096000043.tif11159 Examples of groups formed by this 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, and -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group.

[0081] R a42 Examples of the substituent that may be possessed by include at least one selected from a halogen atom and a group represented by formula (a-g3): Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferred. TIFF2023118096000044.tif965[In formula (a-g3), X a43 represents an oxygen atom, a carbonyl group, *-O-CO- or *-CO-O-. A a45represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. * represents R a42 represents the binding site with However, R a42 -X a43 -A a45 In R a42 If A does not have a halogen atom, a45 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms and at least one halogen atom.

[0082] A a45 Examples of the aliphatic hydrocarbon group in the formula (I) include alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group; Examples include monocyclic alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups; and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl, adamantyl, and norbornyl groups, and the following groups (* indicates a bonding site): TIFF2023118096000045.tif11159 Examples of groups formed by combination include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic hydrocarbon group-alkyl group.

[0083] R a42 is preferably an aliphatic hydrocarbon group which may have a halogen atom, and more preferably an aliphatic hydrocarbon group having an alkyl group having a halogen atom and / or a group represented by formula (a-g3). R a42When is an aliphatic hydrocarbon group having a halogen atom, it is preferably an aliphatic hydrocarbon group having a fluorine atom, more preferably a perfluoroalkyl group or a perfluorocycloalkyl group, still more preferably a perfluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably a perfluoroalkyl group having 1 to 3 carbon atoms. Examples of perfluoroalkyl groups include perfluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, perfluoroheptyl group, and perfluorooctyl group. Examples of perfluorocycloalkyl groups include perfluorocyclohexyl group. R a42 is an aliphatic hydrocarbon group having a group represented by formula (a-g3), the number of carbon atoms contained in the group represented by formula (a-g3) is a42 The total number of carbon atoms is preferably 15 or less, more preferably 12 or less. When the group represented by formula (a-g3) is contained as a substituent, the number thereof is preferably 1.

[0084] R a42 is an aliphatic hydrocarbon group having a group represented by formula (a-g3), R a42 is more preferably a group represented by formula (a-g2). TIFF2023118096000046.tif879[In formula (a-g2), A a46 represents a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. X a44 represents **-O-CO- or **-CO-O- (** represents A a46 (representing the binding site with A a47 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. However, A a46 , A a47 and X a44 The total number of carbon atoms in A is 18 or less. a46 and A a47 At least one of the groups has at least one halogen atom. * indicates the bonding site with the carbonyl group.]

[0085] A a46 The aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms, and more preferably 1 to 3 carbon atoms. A a47 The aliphatic hydrocarbon group preferably has 4 to 15 carbon atoms, more preferably 5 to 12 carbon atoms, and A a47 is more preferably a cyclohexyl group or an adamantyl group.

[0086] A preferred structure of the group represented by formula (a-g2) is the following structure (* indicates the bonding site with the carbonyl group): TIFF2023118096000047.tif14164

[0087] A a41 Examples of the alkanediyl group in the formula (I) include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane-1,6-diyl; and branched alkanediyl groups such as propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,2-diyl, 1-methylbutane-1,4-diyl, and 2-methylbutane-1,4-diyl. A a41 Examples of the substituent in the alkanediyl group include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms. A a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably an alkanediyl group having 2 to 4 carbon atoms, and even more preferably an ethylene group.

[0088] A in the group represented by formula (a-g1) a42 , A a43 and A a44Examples of the divalent saturated hydrocarbon group represented by include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic hydrocarbon group, and a group formed by combining an alkanediyl group with a divalent alicyclic hydrocarbon group. Specific 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, and a 2-methylpropane-1,2-diyl group. A a42 , A a43 and A a44 Examples of the substituent of the divalent saturated hydrocarbon group represented by the formula include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms. Preferably, s is 0.

[0089] In the group represented by formula (a-g1), X a42 In the following examples, * and ** each represent a bonding site, and ** represents -O-CO-R a42 This is the binding site for TIFF2023118096000048.tif54162

[0090] The structural unit represented by formula (a4-1) includes the structural units shown below and R in the structural unit represented by formula (a4-1) in the structural units shown below. a41 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. JPEG2023118096000049.jpg167144

[0091] TIFF2023118096000050.tif66133

[0092] The structural unit (a4) is preferably a structural unit represented by formula (a4-2). TIFF2023118096000051.tif4365[In formula (a4-2), R f5represents a hydrogen atom or a methyl group. L 44 represents an alkanediyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced with -O- or -CO-. R f6 represents a saturated hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom. However, L 44 and R f6 The maximum total carbon number is 21.]

[0093] L 44 The alkanediyl group having 1 to 6 carbon atoms is A a41 Examples of the alkanediyl group include the same groups as those exemplified as the alkanediyl group in the above. R f6 The saturated hydrocarbon group of R a42 Examples of the groups include the same groups as those exemplified in L 44 As the alkanediyl group having 1 to 6 carbon atoms, an alkanediyl group having 2 to 4 carbon atoms is preferred, and an ethylene group is more preferred.

[0094] Examples of the structural unit represented by formula (a4-2) include structural units represented by formulas (a4-1-1) to (a4-1-11). f5 The structural unit represented by formula (a4-2) also includes a structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom:

[0095] Examples of the structural unit (a4) include a structural unit represented by formula (a4-3). TIFF2023118096000052.tif5771[In formula (a4-3), R f7 represents a hydrogen atom or a methyl group. L 5 represents an alkanediyl group having 1 to 6 carbon atoms. A f13 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms which may contain a fluorine atom. X f12represents *-O-CO- or *-CO-O- (* represents A f13 represents the binding site with ). A f14 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may contain a fluorine atom. However, A f13 and A f14 At least one of L has a fluorine atom, 5 , A f13 and A f14 The total number of carbon atoms in a molecule is limited to 20.

[0096] L 5 The alkanediyl group in a41 Examples of the alkanediyl group include the same groups as those exemplified as the alkanediyl group in the above. A f13 The divalent saturated hydrocarbon group optionally having a fluorine atom in the formula (I) is preferably a divalent chain saturated hydrocarbon group optionally having a fluorine atom and a divalent alicyclic saturated hydrocarbon group optionally having a fluorine atom, and more preferably a perfluoroalkanediyl group. Examples of the divalent chain saturated hydrocarbon group which may have a fluorine atom include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group; and perfluoroalkanediyl groups such as a difluoromethylene group, a perfluoroethylene group, a perfluoropropanediyl group, a perfluorobutanediyl group, and a perfluoropentanediyl group. The divalent alicyclic saturated hydrocarbon group optionally having a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include a cyclohexanediyl group and a perfluorocyclohexanediyl group. Examples of the polycyclic group include an adamantanediyl group, a norbornanediyl group, and a perfluoroadamantanediyl group. A f14 The saturated hydrocarbon group and the saturated hydrocarbon group which may have a fluorine atom are R a42Among these, 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, Preferred are fluorinated alkyl groups such as a hexyl group, a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group, and a perfluorooctyl group, 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, and a perfluoroadamantylmethyl group.

[0097] In formula (a4-3), L 5 is preferably an ethylene group. A f13 The divalent saturated hydrocarbon group is preferably a group containing a divalent chain saturated hydrocarbon group having 1 to 6 carbon atoms and a divalent alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably a divalent chain saturated hydrocarbon group having 2 to 3 carbon atoms. A f14 The saturated hydrocarbon group is preferably a group containing a chain saturated hydrocarbon group having 3 to 12 carbon atoms and a group containing an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably a group containing a chain saturated hydrocarbon group having 3 to 10 carbon atoms and a group containing an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms. f14 is preferably a group containing an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, or an adamantyl group.

[0098] Examples of the structural unit represented by formula (a4-3) include structural units represented by formulas (a4-1'-1) to (a4-1'-11). f7 The structural unit represented by formula (a4-3) also includes a structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom:

[0099] The structural unit (a4) also includes a structural unit represented by formula (a4-4). TIFF2023118096000053.tif4466[In formula (a4-4), R f21 represents a hydrogen atom or a methyl group. A f21 is -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -or-(CH2) j4 -CO-O-(CH2) j5 - represents. j1 to j5 each independently represent an integer of 1 to 6. R f22 represents a saturated hydrocarbon group having 1 to 10 carbon atoms and containing a fluorine atom.]

[0100] R f22 The saturated hydrocarbon group of R a42 Examples of saturated hydrocarbon groups include the same as those represented by R f22 is preferably an alkyl group having 1 to 10 carbon atoms and containing a fluorine atom or an alicyclic hydrocarbon group having 1 to 10 carbon atoms and containing a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and containing a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and containing a fluorine atom.

[0101] In formula (a4-4), A f21 As -(CH2) j1 - is preferred, an ethylene group or a methylene group is more preferred, and a methylene group is even more preferred.

[0102] Examples of the structural unit represented by formula (a4-4) include the following structural units and structural units represented by the following formulas: f21 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2023118096000054.tif90164

[0103] When the resin contains the structural unit (a4), the content thereof is preferably from 1 to 20 mol %, more preferably from 2 to 15 mol %, and even more preferably from 3 to 10 mol %, based on the total structural units of the resin.

[0104] <Structural unit (a5)> The non-leaving hydrocarbon group contained in the structural unit (a5) may be a group containing a linear, branched, or cyclic hydrocarbon group, and among these, the structural unit (a5) is preferably a group containing an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by formula (a5-1). TIFF2023118096000055.tif3971[In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a 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 -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.]

[0105] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Examples of polycyclic alicyclic hydrocarbon groups include adamantyl and norbornyl. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group. L 55 The divalent saturated hydrocarbon group in the formula (I) includes a divalent saturated chain hydrocarbon group and a divalent saturated alicyclic hydrocarbon group, and is preferably a divalent saturated chain hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include a methylene group, an ethylene group, and an alkanediyl group such as a propanediyl group, a butanediyl group, and a 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 and cyclohexanediyl. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl and norbornanediyl.

[0106] L 55 Examples of the divalent saturated hydrocarbon group represented by formula (L1-1) in which one -CH2- is replaced with -O- or -CO- include groups represented by formula (L1-1) to formula (L1-4). In the following formulae, * and ** each represent a bonding site, and * represents a bonding site to an oxygen atom. TIFF2023118096000056.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 represents the binding site with ). 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, L x1 and L x2 The total number of carbon atoms 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, L x3 and L x4 The total number of carbon atoms 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 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, L x5 , L x6 and L x7 The total number of carbon atoms is 15 or less. In formula (L1-4), L x8 and L x9 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, L x8 , L x9 and W x1 The total number of carbon atoms is 15 or less.

[0107] 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.

[0108] Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF2023118096000057.tif37147 Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF2023118096000058.tif23130 Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF2023118096000059.tif16147 Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF2023118096000060.tif13168L 55 is preferably a single bond or a group represented by formula (L1-1).

[0109] The structural unit (a5-1) includes the structural units shown below and R in the structural unit (a5-1) in the structural units shown below. 51 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. When the resin contains the structural unit (a5), the content thereof is preferably from 1 to 30 mol %, more preferably from 2 to 20 mol %, and even more preferably from 3 to 15 mol %, based on the total structural units of the resin.

[0110] <Structural unit (a6)> The structural unit (a6) is a structural unit having an -SO2- group, and preferably has an -SO2- group in a side chain. The structural unit having an -SO2- group may have a linear structure having an -SO2- group, a branched structure having an -SO2- group, or a cyclic structure (monocyclic or polycyclic structure) having an -SO2- group. A structural unit having a cyclic structure having an -SO2- group is preferred, and a structural unit having a cyclic structure containing an -SO2-O- group (sultone ring) is more preferred.

[0111] The sultone ring may be a ring having the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and the formula (T 1 The bonding site can be any position. The sultone ring may be monocyclic, but is preferably polycyclic. A polycyclic sultone ring refers to a bridged ring containing -SO2-O- as an atomic group constituting the ring, and is represented by the formula (T 1 -1) and the formula (T 1 The sultone ring is represented by the formula (T 1 As in the ring represented by formula (2), the atomic group constituting the ring may further contain a heteroatom in addition to —SO—O—. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom, and an oxygen atom is preferred. TIFF2023118096000062.tif3186

[0112] The sultone ring may have a substituent, and examples of the substituent include an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an alkylcarbonyl group having 2 to 4 carbon atoms.

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

[0114] From the viewpoint of ease of production of the monomer from which the structural unit (a6) is derived, a sultone ring having no substituent is preferred. The sultone ring is preferably a ring represented by the following formula (T1'). TIFF2023118096000063.tif3171[In formula (T1'), X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents an integer of 0 to 9. When ma is 2 or more, multiple R 41 may be the same or different. The binding site is at any position.] X 11 is preferably an oxygen atom or a methylene group, more preferably a methylene group. R 41 Examples of the substituent include the same as the substituent on the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group is preferred. ma is preferably 0 or 1, and more preferably 0.

[0115] Examples of the ring represented by formula (T1') include the following rings: The bonding site may be any position, and the bonding site is preferably the 1st or 3rd position. TIFF2023118096000064.tif47147

[0116] The structural unit having an -SO2- group preferably further has a group derived from a polymerizable group, such as a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, or a methacryloylthio group. Among these, the monomer from which the structural unit (a6) is derived is preferably a monomer having an ethylenically unsaturated bond, and more preferably a (meth)acrylic monomer.

[0117] The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2023118096000065.tif4963[In formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. A xx is an oxygen atom, -N(R c )- or a sulfur atom. A x represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group is not -O-, -CO- or -N(R d )- may be replaced. X 11 , R 41 and ma have the same meanings as above. R c and R d each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

[0118] R x Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R x 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, an n-pentyl group, and an n-hexyl group, and are preferably alkyl groups 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 include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. R x is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0119] A x Examples of the divalent saturated hydrocarbon group include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and may be a combination of two or more of these groups. Specifically, 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 linear alkanediyl groups such as a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, a heptadecane-1,17-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group; branched alkanediyl groups such as butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; Examples include polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. A x The bonding position of to the sultone ring can be any position, but the 1-position is preferred.

[0120] Examples of the structural unit (a6-0) include the following structural units. TIFF2023118096000066.tif92150

[0121] Of these, 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 structural units represented by formula (a6-1), formula (a6-2), formula (a6-7), and formula (a6-8) are more preferred. When the resin has the structural unit (a6), the content thereof is preferably from 1 to 50 mol %, more preferably from 2 to 40 mol %, and even more preferably from 3 to 30 mol %, based on the total structural units of the resin.

[0122] <Structural unit (II)> The resin may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter, sometimes referred to as "structural unit (II)"). Specific examples of the structural unit (II) include the structural units described in JP-A-2016-79235, and the structural unit (II) is preferably a structural unit having a sulfonate group or carboxylate group and an organic cation in a side chain, or a structural unit having a sulfonio group and an organic anion in a side chain.

[0123] The structural unit having a sulfonate group or carboxylate group and an organic cation on the side chain is preferably a structural unit represented by formula (II-2-A'). TIFF2023118096000067.tif35104[In formula (II-2-A'), X III3 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, wherein one -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -S-, or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be replaced by a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, or a hydroxy group. A x1 represents an alkanediyl group having 1 to 8 carbon atoms, and a hydrogen atom contained in the alkanediyl group may be substituted with a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. RA - represents a sulfonate group or a carboxylate group. R III3 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. ZA + represents an organic cation.

[0124] R III3 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R III3 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom and is represented by the formula: a8 Examples of the alkyl group include the same alkyl groups having 1 to 6 carbon atoms which may have a halogen atom and which are represented by the following formula: A x1Examples of the alkanediyl group having 1 to 8 carbon atoms represented by the formula (I) include 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, 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. A X1 Examples of the optionally substituted perfluoroalkyl group having 1 to 6 carbon atoms include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. X III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by the formula (I) include a linear or branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and these may be used in combination. Specific examples thereof include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl; butane-1,3-diyl, 2-methylpropane-1,3-diyl, and 2-methylpropane-1,3-diyl; Examples include branched alkanediyl groups such as pentane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; cycloalkanediyl groups such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; and divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, and adamantane-2,6-diyl. Examples of saturated hydrocarbon groups in which -CH2- is replaced with -O-, -S-, or -CO- include divalent groups represented by formulae (X1) to (X53). However, the number of carbon atoms before the -CH2- in the saturated hydrocarbon group is replaced with -O-, -S-, or -CO- is 17 or less. In the following formulae, * and ** represent bonding sites, and * represents A x1 represents the binding site with JPEG2023118096000068.jpg145161

[0125] X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0126] ZA in formula (II-2-A') + is the cation Z1 in the salt represented by formula (B1) + The same can be mentioned.

[0127] The structural unit represented by formula (II-2-A') is preferably a structural unit represented by formula (II-2-A). TIFF2023118096000069.tif38109 [In formula (II-2-A), R III3 , X III3 and ZA + has the same meaning as above. z2A represents an integer of 0 to 6. R III2 and R III4 each independently represents a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 6 carbon atoms; when z2A is 2 or more, a plurality of R III2 and R III4 may be the same as or different from each other. Q a and Q b each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.] R III2 , R III4 , Q a and Q b As the perfluoroalkyl group having 1 to 6 carbon atoms represented by the formula, the above-mentioned Q b1 Examples include the same perfluoroalkyl groups having 1 to 6 carbon atoms as those represented by the following formula:

[0128] The structural unit represented by formula (II-2-A) is preferably a structural unit represented by formula (II-2-A-1). TIFF2023118096000070.tif5577 [In formula (II-2-A-1), R III2 , R III3 , R III4 , Q a , Qb and ZA + has the same meaning as above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. z2A1 represents an integer of 0 to 6. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, wherein -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -S-, or -CO-, and wherein a hydrogen atom contained in the saturated hydrocarbon group may be substituted by a halogen atom or a hydroxy group. R III5 Examples of the saturated hydrocarbon group having 1 to 12 carbon atoms represented by the formula (I) include linear or branched alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. X I2 As the divalent saturated hydrocarbon group represented by X III3 Examples of the divalent saturated hydrocarbon group include those similar to those represented by the following formula:

[0129] As the structural unit represented by formula (II-2-A-1), a structural unit represented by formula (II-2-A-2) is more preferred. TIFF2023118096000071.tif5287 [In formula (II-2-A-2), R III3 , R III5 and ZA + has the same meaning as above. m and nA each independently represent 1 or 2.

[0130] Examples of the structural unit represented by formula (II-2-A') include the following structural units, R III3 Examples of such a structural unit include a structural unit in which the group corresponding to the methyl group in the formula (1) is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group), and the structural units described in WO 2012 / 050015.+ represents an organic cation. TIFF2023118096000072.tif86163

[0131] The structural unit having a sulfonio group and an organic anion on the side chain is preferably a structural unit represented by formula (II-1-1). TIFF2023118096000073.tif3791 [In formula (II-1-1), A II1 represents a single bond or a divalent linking group. R II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R II2 and R II3 each independently represents a hydrocarbon group having 1 to 18 carbon atoms; R II2 and R II3 may be bonded to each other to form a ring together with the sulfur atom to which they are attached. R II4 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A - represents an organic anion. R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by the formula include a phenylene group and a naphthylene group. R II2 and R II3 Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the alkyl group and the alicyclic hydrocarbon group include the same as those described above. Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group combining the above-mentioned alkyl group and alicyclic hydrocarbon group, aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), and aryl-cycloalkyl groups such as phenylcyclohexyl group. II4 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R II4 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom and is represented by the formula: a8 Examples of the alkyl group include the same alkyl groups having 1 to 6 carbon atoms which may have a halogen atom and which are represented by the following formula: A II1 Examples of the divalent linking group represented by the formula (I) include a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-. III3 Examples include the same divalent saturated hydrocarbon groups having 1 to 18 carbon atoms as those represented by the following formula:

[0132] The structural unit containing a cation in formula (II-1-1) includes the structural unit represented by the following formula and R II4 Examples of structural units include those in which a group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group). TIFF2023118096000074.tif71163

[0133] A - Examples of the organic anion represented by the formula (A) include a sulfonate anion, a sulfonylimide anion, a sulfonylmethide anion, and a carboxylate anion. -The organic anion represented by the formula (B1) is preferably a sulfonate anion, and the sulfonate anion is more preferably an anion contained in the salt represented by the formula (B1) above.

[0134] A - Examples of the sulfonylimide anion represented by the formula (I) include the following. JPEG2023118096000075.jpg23136 Examples of sulfonylmethide anions include the following: TIFF2023118096000076.tif26133Carboxylate anions include the following: TIFF2023118096000077.tif43155

[0135] Examples of the structural unit represented by formula (II-1-1) include structural units represented by the following formulas. JPEG2023118096000078.jpg88149

[0136] When the resin contains the structural unit (II), the content of the structural unit (II) is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and even more preferably 3 to 10 mol %, based on the total structural units of the resin.

[0137] The resin may contain structural units other than those described above, including structural units well known in the art.

[0138] In one embodiment of the resist composition of the present invention, it is preferred that one resin among the one or more resins contained in the resist composition contains both the structural unit (I) and the structural unit (a2-A). The resin containing the structural unit (I) and the structural unit (a2-A) is preferably a resin consisting of the structural unit (I), the structural unit (a2-A), and the structural unit (a1), a resin consisting of the structural unit (I), the structural unit (a2-A), and the structural unit (a2) and / or the structural unit (a3), a resin consisting of the structural unit (I), the structural unit (a2-A), the structural unit (a1), the structural unit (a2), ... The resins are those composed of the structural unit (a3) ​​and the structural unit (a4) and / or the structural unit (a5), those composed of the structural unit (I) and the structural unit (a2-A), or those composed only of the structural unit (I), the structural unit (a2-A), and the structural unit (a4). More preferably, the resins are those composed of the structural unit (I), the structural unit (a2-A), the structural unit (a1), the structural unit (a2), and / or the structural unit (a3), or those composed of the structural unit (I), the structural unit (a2-A), the structural unit (a2) and / or the structural unit (a3). In resins containing both the structural unit (I) and the structural unit (a2-A), the content of the structural unit (I) relative to all structural units is preferably 1 mol% or more, more preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more. It may also be 90 mol% or less, more preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, it may be 1 to 90 mol%, preferably 5 to 80 mol%, more preferably 10 to 80 mol%, even more preferably 15 to 70 mol%, and even more preferably 15 to 60 mol%. The content of the structural unit (a2-A) relative to all structural units is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and even more preferably 20 mol% or more. It may also be 80 mol% or less, more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, even more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%. The total content of the structural unit (I) and the structural unit (a2-A) relative to all structural units is preferably 6 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, and even more preferably 30 mol% or more. It may also be 100 mol% or less, preferably 95 mol% or less, more preferably 85 mol% or less, and even more preferably 75 mol% or less. Specifically, it is preferably 6 to 100 mol%, more preferably 15 to 95 mol%, even more preferably 20 to 95 mol%, even more preferably 30 to 95 mol%, even more preferably 30 to 85 mol%, and even more preferably 30 to 75 mol%. The ratio of the structural unit (I) to the structural unit (a2-A) in the resin is preferably 5:95 to 95:5.

[0139] In one embodiment of the resist composition of the present invention, of the two or more resins contained in the resist composition, one of the two resins is a resin that contains a structural unit represented by formula (I), and the other is a resin that contains a structural unit represented by formula (a2-A). The resin having the structural unit represented by formula (I) is preferably a resin consisting of the structural unit (I) and the structural unit (a1), a resin consisting of the structural unit (I) and the structural unit (a2) and / or the structural unit (a3), a resin consisting of the structural unit (I), the structural unit (a1), the structural unit (a2) and / or the structural unit (a3), a resin consisting of the structural unit (I), the structural unit (a1), the structural unit (a2) and / or the structural unit (a3), and the structural unit (a4) and / or the structural unit (a5), a resin consisting of the structural unit (I), or a resin consisting only of the structural unit (I) and the structural unit (a4), and more preferably a resin consisting of the structural unit (I), the structural unit (a1), the structural unit (a2) and / or the structural unit (a3), a resin consisting of the structural unit (I), the structural unit (a2) and / or the structural unit (a3), or a resin consisting of the structural unit (I). The resin having a structural unit represented by formula (a2-A) is preferably a resin composed of the structural unit (a2-A) and the structural unit (a1), a resin composed of the structural unit (a2-A) and the structural unit (a2) and / or the structural unit (a3), a resin composed of the structural unit (a2-A), the structural unit (a1), the structural unit (a2) and / or the structural unit (a3), a resin composed of the structural unit (a2-A), the structural unit (a1), the structural unit (a2) and / or the structural unit (a3), and the structural unit (a4) and / or the structural unit (a5), or a resin composed only of the structural unit (a2-A) and the structural unit (a4), and more preferably a resin composed of the structural unit (a2-A), the structural unit (a1), the structural unit (a2) and / or the structural unit (a3).

[0140] In the case of a resist composition containing a resin containing a structural unit represented by formula (I) and a resin containing a structural unit represented by formula (a2-A), the content of the structural unit (I) relative to all structural units in the resin containing the structural unit represented by formula (I) is preferably 10 mol% or more, more preferably 30 mol% or more, even more preferably 50 mol% or more, and even more preferably 70 mol% or more. It can also be 100 mol% or less. Specifically, it is preferably 10 mol% to 100 mol%, more preferably 30 mol% to 100 mol%, even more preferably 50 mol% to 100 mol%, and even more preferably 70 mol% to 100 mol%. In the resin containing the structural unit represented by formula (a2-A), the content of the structural unit (a2-A) relative to all structural units is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and even more preferably 20 mol% or more. Also, it is preferably 80 mol % or less, more preferably 70 mol % or less, and even more preferably 65 mol % or less. Specifically, it is preferably 5 to 80 mol %, more preferably 10 to 70 mol %, even more preferably 15 to 65 mol %, and even more preferably 20 to 65 mol %.

[0141] 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). In one embodiment of the resist composition of the present invention, of the two or more resins contained in the resist composition, one of the two resins is a resin that contains a structural unit represented by formula (I), and the other is a resin that contains a structural unit represented by formula (a2-A) and at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2). In one embodiment of the resist composition of the present invention, one resin among the one or more resins contained in the resist composition is a resin that contains a structural unit represented by formula (I), a structural unit represented by formula (a2-A), and at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2). The structural unit (a2) is preferably the structural unit (a2-A) or the structural unit (a2-1). The structural unit (a3) ​​is preferably at least one selected from the group consisting of the structural unit represented by formula (a3-1), the structural unit represented by formula (a3-2), and the structural unit represented by formula (a3-4), and more preferably the structural unit represented by formula (a3-4). In one embodiment of the resist composition of the present invention, of the two or more resins contained in the resist composition, one of the two resins is a resin that contains a structural unit represented by formula (I), and the other is a resin that contains a structural unit represented by formula (a2-A), at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2), and at least one structural unit selected from the group consisting of a structural unit represented by formula (a2-1), and a structural unit represented by formula (a3-1), a structural unit represented by formula (a3-2), a structural unit represented by formula (a3-3), and a structural unit represented by formula (a3-4). In one embodiment of the resist composition of the present invention, one resin among the one or more resins contained in the resist composition is a resin that contains a structural unit represented by formula (I), a structural unit represented by formula (a2-A), at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2), and at least one structural unit selected from the group consisting of a structural unit represented by formula (a2-1), and a structural unit represented by formula (a3-1), a structural unit represented by formula (a3-2), a structural unit represented by formula (a3-3), and a structural unit represented by formula (a3-4). The weight-average molecular weight of resin (A) is preferably 2,000 or more (more preferably 2,500 or more, even more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, even more preferably 15,000 or less), but it may contain oligomers with lower weight-average molecular weights. In this specification, the weight-average molecular weight is a value determined by gel permeation chromatography under the conditions described in the Examples.

[0142] [Method of synthesizing resin] Each structural unit constituting the resin may be used alone or in combination of two or more types, and can be produced by a known polymerization method (e.g., radical polymerization) using a monomer that leads to the desired structural unit. The content of each structural unit in the resin can be adjusted by the amount of monomer used in polymerization. Each monomer may be synthesized by a conventionally known method or obtained commercially. Alternatively, the resin synthesized by the polymerization reaction may be treated with an acid or alkali to incorporate the desired structural unit into the resin. For example, the structural unit (a2-A) can be incorporated into the resin (A) by polymerizing the structural unit (a1-4) and then treating with an acid such as p-toluenesulfonic acid. Alternatively, the structural unit (a2-A) can be incorporated into the resin by polymerizing the resin using acetoxystyrene or the like and then treating with an alkali such as tetramethylammonium hydroxide.

[0143] [Resist Composition] The resist composition of the present invention preferably contains a resin (A) and an acid generator known in the resist field (hereinafter sometimes referred to as "acid generator (B)"). The resist composition of the present invention may further contain a resin other than the resin (A). The resist composition of the present invention preferably contains a quencher such as a salt that generates an acid with a weaker acidity than the acid generated from the acid generator (hereinafter may be referred to as "quencher (C)"), and preferably contains a solvent (hereinafter may be referred to as "solvent (E)").

[0144] The resist composition of the present invention may contain a resin that does not contain the structural unit (I) and / or the structural unit (a2-A). Examples of such resins include a resin consisting solely of the structural unit (a4) and a resin consisting of the structural unit (a4) and the structural unit (a5) (hereinafter, a resin consisting solely of the structural unit (a4) and a resin consisting of the structural unit (a4) and the structural unit (a5) may be collectively referred to as resin (X)). Among these, resins (X) containing the structural unit (a4) are preferred, including resins consisting of only the structural unit (a4) and resins containing the structural unit (a4) and the structural unit (a5). Examples of structural units that the resin (X) may further contain include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. When resin (X) contains structural unit (a4), the content of structural unit (a4) in resin (X) is, based on the total of all structural units in resin (X), 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Also, it may be 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it may be 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even 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) in resin (X) is, based on the total of all structural units in resin (X), 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Further, it may be 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specific examples include 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. Furthermore, when the resin (X) contains the structural unit (a4) and the structural unit (a5), the total content of the structural unit (a4) and the structural unit (a5) relative to the total of all structural units in the resin (X) may be 40 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more. Specific examples include 100 mol% or less. Specific examples include 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and even more preferably 80 to 100 mol%. Each structural unit constituting the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization) using a monomer that derives these structural units. The content of each structural unit in the resin (X) can be adjusted by the amount of monomer used in the polymerization. The weight-average molecular weight of resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less), but may contain oligomers with a lower weight-average molecular weight. The weight-average molecular weight of resin (X) can be measured by the same method as for resin (A). Furthermore, when the resist composition contains resin (X), the content thereof is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, even more preferably 1 to 40 parts by mass, still more preferably 1 to 30 parts by mass, and even more preferably 1 to 8 parts by mass, relative to 100 parts by mass of resin (A).

[0145] The content of resins containing the structural unit (I) and / or the structural unit (a2-A) in the resist composition is preferably 80% to 99% by mass, and more preferably 90% to 99% by mass, based on the solid content of the resist composition. Furthermore, when a resin that does not contain the structural unit (I) and / or the structural unit (a2-A) is included, the total content of all resins in the resist composition is preferably 80% to 99% by mass, and more preferably 90% to 99% by mass, based on the solid content of the resist composition. The solid content of the resist composition and the resin content relative to the solid content can be measured using known analytical methods such as liquid chromatography or gas chromatography.

[0146] <Acid generator (B)> The acid generator (B) may be either nonionic or ionic. Nonionic acid generators include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), etc. Ionic acid generators include onium salts containing onium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Anions of onium salts include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, etc. The acid generator (B) may be a compound that generates an acid when exposed to radiation, 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. Pat. No. 3,779,778, U.S. Pat. No. 3,849,137, German Patent No. 3,914,407, or European Patent No. 126,712. Compounds produced by known methods may also be used. Two or more types of acid generator (B) may be used in combination.

[0147] The acid generator (B) is preferably a salt represented by formula (B1) (hereinafter, sometimes referred to as "acid generator (B1)"). TIFF2023118096000079.tif2862[In formula (B1), Q b1 and Q b2 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. L b1 represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, in which -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-, and in which a hydrogen atom contained in the saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. Y represents an optionally substituted methyl group or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. Z1 + represents an organic cation.

[0148] Q b1 and Q b2 Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Q b1 and Q b2 Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. Q b1 and Q b2 and preferably either one of them is a fluorine atom or a perfluoroalkyl group, more preferably each independently is a fluorine atom or a trifluoromethyl group, and further preferably both are fluorine atoms.

[0149] L b1 Examples of the divalent saturated hydrocarbon group in include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and may also be a group formed by combining two or more of these groups. Specific examples 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; branched alkanediyl groups such as ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; Examples include polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group.

[0150] L b1 Examples of the divalent saturated hydrocarbon group represented by the formula (b1-1) in which one -CH2- is replaced with -O- or -CO- include groups represented by any of formulas (b1-1) to (b1-3). In the groups represented by formulas (b1-1) to (b1-3) and specific examples thereof, groups represented by formulas (b1-4) to (b1-11), * and ** represent bonding sites, and * represents the bonding site to -Y.

[0151] TIFF2023118096000080.tif26117 [In formula (b1-1), L b2represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b2 and L b3 The total number of carbon atoms is 22 or less. In formula (b1-2), L b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b4 and L b5 The total number of carbon atoms is 22 or less. In formula (b1-3), L b6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. L b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b6 and L b7 The total number of carbon atoms is 23 or less.

[0152] In the groups represented by formulae (b1-1) to (b1-3), when -CH2- contained in the saturated hydrocarbon group is replaced with -O- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the saturated hydrocarbon group. As the divalent saturated hydrocarbon group, L b1 Examples of the divalent saturated hydrocarbon group include the same as the divalent saturated hydrocarbon group.

[0153] L b2 is preferably a single bond, a methylene group, —CH(CF3)—, or —C(CF3)2—. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom, and is more preferably a methylene group, -CH(CF3)-, or -C(CF3)2-. L b5 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b6 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b7 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the divalent saturated hydrocarbon group may be substituted with -O- or -CO-.

[0154] L b1 As the divalent saturated hydrocarbon group represented by the formula (b1-1) or (b1-3), in which one --CH.sub.2-- contained in the group is replaced by --O-- or --CO--, a group represented by the formula (b1-1) or (b1-3) is preferred. Examples of the group represented by formula (b1-1) include groups represented by formulas (b1-4) to (b1-8). TIFF2023118096000081.tif49119[In formula (b1-4), Lb8 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. In formula (b1-5), L b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b10 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b9 and L b10 The total number of carbon atoms is 20 or less. In formula (b1-6), L b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b11 and L b12 The total number of carbon atoms is 21 or less. In formula (b1-7), L b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. L b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b13 ~L b15 The total number of carbon atoms is 19 or less. In formula (b1-8), L b16represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b17 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms. L b18 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b16 ~L b18 The total number of carbon atoms is 19 or less. L b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0155] Examples of the group represented by formula (b1-3) include groups represented by formulas (b1-9) to (b1-11). TIFF2023118096000082.tif24140[In formula (b1-9), L b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b19 and L b20 The total number of carbon atoms is 23 or less. In formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b21 , L b22 and Lb23 The total number of carbon atoms is 21 or less. In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b24 , L b25 and L b26 The total number of carbon atoms is 21 or less.

[0156] In addition, in the groups represented by formulae (b1-9) to (b1-11), when a hydrogen atom contained in the saturated hydrocarbon group is substituted with an alkylcarbonyloxy group, the number of carbon atoms before substitution is defined as the number of carbon atoms in the saturated hydrocarbon group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, and an adamantylcarbonyloxy group.

[0157] Examples of the group represented by formula (b1-4) include the following. TIFF2023118096000083.tif14133

[0158] Examples of the group represented by formula (b1-5) include the following. TIFF2023118096000084.tif60150

[0159] Examples of the group represented by formula (b1-6) include the following. TIFF2023118096000085.tif29165

[0160] Examples of the group represented by formula (b1-7) include the following. TIFF2023118096000086.tif41169

[0161] Examples of the group represented by formula (b1-8) include the following. TIFF2023118096000087.tif20123

[0162] Examples of the group represented by formula (b1-2) include the following. TIFF2023118096000088.tif31161

[0163] Examples of the group represented by formula (b1-9) include the following. TIFF2023118096000089.tif34152

[0164] Examples of the group represented by formula (b1-10) include the following. TIFF2023118096000090.tif80165

[0165] Examples of the group represented by formula (b1-11) include the following. TIFF2023118096000091.tif67153

[0166] Examples of the alicyclic hydrocarbon group represented by Y in which -CH2- is not replaced by -O-, -S-, -SO2-, or -CO- include groups represented by formulae (Y1) to (Y11) and formulae (Y36) to (Y38). When -CH2- contained in the alicyclic hydrocarbon group represented by Y is replaced by -O-, -S-, -SO2- or -CO-, the number may be one or more. Examples of such groups include groups represented by formulae (Y12) to (Y35) and formulae (Y39) to (Y43). -O- or -CO- in the groups represented by formulae (Y12) to (Y35) and formulae (Y39) to (Y43) may be replaced by -S- or -SO2-. * represents L b1 represents the binding site with TIFF2023118096000092.tif84163

[0167] The alicyclic hydrocarbon group represented by Y is preferably a group represented by any one of formulas (Y1) to (Y20), (Y26), (Y27), (Y30), (Y31), and (Y39) to (Y43), more preferably a group represented by formula (Y11), (Y15), (Y16), (Y20), (Y26), (Y27), (Y30), (Y31), (Y39), (Y40), (Y42), or (Y43), and even more preferably a group represented by formula (Y11), (Y15), (Y20), (Y26), (Y27), (Y30), (Y31), (Y39), (Y40), (Y42), or (Y43). When the alicyclic hydrocarbon group represented by Y is a spiro ring having an oxygen atom such as those of formula (Y28) to formula (Y35), formula (Y39), formula (Y40), formula (Y42) or formula (Y43), the alkanediyl group between the two oxygen atoms preferably has one or more fluorine atoms. Furthermore, among the alkanediyl groups contained in the ketal structure, it is preferred that the methylene group adjacent to the oxygen atom is not substituted with a fluorine atom.

[0168] The substituent of the methyl group represented by Y is a halogen atom, a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-OR b1 group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof. ja represents an integer of 0 to 4. -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2-, or -CO-, and a hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. Substituents of the alicyclic hydrocarbon group represented by Y include a halogen atom, a hydroxy group, an alkyl group having 1 to 16 carbon atoms which may be substituted with a hydroxy group (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-OR b1 group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof. ja represents an integer of 0 to 4. -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2-, or -CO-, and a hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom.

[0169] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a norbornyl group, and an adamantyl group. The alicyclic hydrocarbon group may have a chain hydrocarbon group, such as a methylcyclohexyl group or a dimethylcyclohexyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 12, and more preferably 3 to 10. Examples of aromatic hydrocarbon groups include aryl groups such as phenyl, naphthyl, anthryl, biphenyl, and phenanthryl. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples include aromatic hydrocarbon groups having a chain hydrocarbon group with 1 to 18 carbon atoms (such as tolyl, xylyl, cumenyl, mesityl, p-methylphenyl, p-ethylphenyl, p-tert-butylphenyl, 2,6-diethylphenyl, and 2-methyl-6-ethylphenyl), and aromatic hydrocarbon groups having an alicyclic hydrocarbon group with 3 to 18 carbon atoms (such as p-cyclohexylphenyl and p-adamantylphenyl). The aromatic hydrocarbon group preferably has 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, 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 in the alkyl group is preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkyl group substituted with a hydroxy group include hydroxyalkyl groups such as a hydroxymethyl group and a hydroxyethyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of groups in which -CH2- in an alkyl group is replaced by -O-, -SO2-, -CO-, etc. include an alkoxy group, an alkylsulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, or a combination thereof. 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 preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, etc. The alkylsulfonyl group preferably has 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group, etc. The alkoxycarbonyl group preferably has 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group preferably has 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, etc. The alkylcarbonyloxy group preferably has 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the combined group include a group combining an alkoxy group and an alkyl group, a group combining an alkoxy group and an alkoxy group, a group combining an alkoxy group and an alkylcarbonyl group, and a group combining an alkoxy group and an alkylcarbonyloxy group. Examples of the group combining an alkoxy group and an alkyl group include alkoxyalkyl groups such as a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, an ethoxymethyl group, etc. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of a group formed by combining an alkoxy group with another alkoxy group include alkoxyalkoxy groups such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, etc. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the group combining an alkoxy group and an alkylcarbonyl group include alkoxyalkylcarbonyl groups such as a methoxyacetyl group, a methoxypropionyl group, an ethoxyacetyl group, an ethoxypropionyl group, etc. The number of carbon atoms in the alkoxyalkylcarbonyl group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group combining an alkoxy group and an alkylcarbonyloxy group include alkoxyalkylcarbonyloxy groups such as a methoxyacetyloxy group, a methoxypropionyloxy group, an ethoxyacetyloxy group, an ethoxypropionyloxy group, etc. The number of carbon atoms in the alkoxyalkylcarbonyloxy group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group in which -CH2- in the alicyclic hydrocarbon group is replaced by -O-, -SO2-, -CO- or the like include groups represented by formulae (Y12) to (Y35) and formulae (Y39) to (Y43).

[0170] Y is preferably an alicyclic hydrocarbon group of 3 to 24 carbon atoms which may have a substituent, more preferably an alicyclic hydrocarbon group of 3 to 20 carbon atoms which may have a substituent, even more preferably an alicyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent, and even more preferably an adamantyl group which may have a substituent or a norbornyl group which may have a substituent, wherein -CH2- constituting the alicyclic hydrocarbon group, adamantyl group or norbornyl group may be replaced by -O-, -S-, -SO2- or -CO-. Specific examples include the following. TIFF2023118096000093.tif116158

[0171] TIFF2023118096000094.tif54155 Among these, Y is preferably an adamantyl group, a hydroxyadamantyl group, an oxoadamantyl group, a norbornane lactone group, or a group represented by formula (Y42), formula (Y100) to formula (Y114), or formula (Y134) to formula (Y139), and particularly preferably a hydroxyadamantyl group, oxoadamantyl group, a group containing these, or a group represented by formula (Y42), formula (Y100) to formula (Y114), or formula (Y134) to formula (Y139).

[0172] The anion in the salt represented by formula (B1) is preferably an anion represented by formula (B1-A-1) to formula (B1-A-65) (hereinafter, sometimes referred to as "anion (B1-A-1)" depending on the formula number).), and more preferably an anion represented by any of formula (B1-A-1) to formula (B1-A-4), formula (B1-A-9), formula (B1-A-10), formula (B1-A-24) to formula (B1-A-33), formula (B1-A-36) to formula (B1-A-40), and formula (B1-A-47) to formula (B1-A-65). TIFF2023118096000095.tif231165

[0173] TIFF2023118096000096.tif238165

[0174] TIFF2023118096000097.tif202165Here 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. 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. A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. b1 and Q b2 has the same meaning as above. Specific examples of the anion in the salt represented by formula (B1) include the anions described in JP-A-2010-204646.

[0175] Preferable anions in the salt represented by formula (B1) include anions represented by formulas (B1a-1) to (B1a-43). TIFF2023118096000098.tif236167

[0176] TIFF2023118096000099.tif103155

[0177] Among these, anions represented by any one of formulas (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), and (B1a-35) to (B1a-41) are preferred. Examples of the sulfonylimide anion and sulfonylmethide anion include those similar to those described above.

[0178] 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 are more preferred. Specific examples include cations represented by any of formulas (b2-1) to (b2-4) (hereinafter, sometimes referred to as "cation (b2-1)" depending on the formula number). TIFF2023118096000100.tif45166 [In formulas (b2-1) to (b2-4), R b4 ~R b6 each independently represent a chain hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, a hydrogen atom contained in the chain hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, a 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 a 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 attached, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of 0 to 5; When m2 is 2 or more, multiple R b7may be the same or different, and when n2 is 2 or more, multiple R b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 and may be bonded to each other to form a ring together with the sulfur atom to which they are attached, and -CH2- contained in the ring may be replaced with -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 a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including the -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 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 may be bonded to each other to form a ring containing a sulfur atom together with the benzene ring to which they are attached, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. L b31 represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of 0 to 5. q2 and r2 each independently represent an integer of 0 to 4; u2 represents 0 or 1. When o2 is 2 or more, multiple R b13 are the same or different, and when p2 is 2 or more, multiple R b14 are the same or different, and when q2 is 2 or more, multiple R b15 are the same or different, and when r2 is 2 or more, multiple R b16 are the same or different, and when s2 is 2 or more, multiple R b17 are the same or different, and when t2 is 2 or more, multiple R b18 are the same or different.] When u2 is 0, any one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16 At least one of o2, p2, s2, t2, q2 and r2 is preferably a halogen atom, and 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 these is preferably a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, and more preferably 1. When u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom. The aliphatic hydrocarbon group refers to a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. In particular, R b9 ~R b12 The chain hydrocarbon group preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups: TIFF2023118096000101.tif10158 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, and more preferably has 4 to 12 carbon atoms. 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 methylnorbornyl group, an isobornyl group, etc. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms in the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The fluorinated alkyl group refers to an alkyl group having 1 to 12 carbon atoms and a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluorobutyl group, etc. The number of carbon atoms in the fluorinated alkyl group is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4.

[0179] Examples of aromatic hydrocarbon groups include aryl groups such as phenyl, biphenyl, naphthyl, and phenanthryl. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples include aromatic hydrocarbon groups having a chain hydrocarbon group of 1 to 18 carbon atoms (such as tolyl, xylyl, cumenyl, mesityl, p-ethylphenyl, p-tert-butylphenyl, 2,6-diethylphenyl, and 2-methyl-6-ethylphenyl), and aromatic hydrocarbon groups having an alicyclic hydrocarbon group of 3 to 18 carbon atoms (such as p-cyclohexylphenyl and p-adamantylphenyl). When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, chain hydrocarbon groups having 1 to 18 carbon atoms and alicyclic hydrocarbon groups having 3 to 18 carbon atoms are preferred. Examples of aromatic hydrocarbon groups in which hydrogen atoms are substituted with alkoxy groups include p-methoxyphenyl groups. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl, and naphthylethyl. 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 alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. 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, and a 2-ethylhexylcarbonyloxy group. R b4 and R b5and bond to each other together with the sulfur atom to which they are bonded to form a ring which may be monocyclic, polycyclic, aromatic, non-aromatic, saturated, or unsaturated. This ring may be a ring having 3 to 18 carbon atoms, preferably a ring having 4 to 18 carbon atoms. The ring containing a sulfur atom may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring, for example, the following rings. * represents a bonding site. TIFF2023118096000102.tif23143R b9 and R b10 The ring formed by these together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring. Examples thereof include a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium ring. R b11 and R b12 The ring formed by combining these may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include a 3- to 12-membered ring, and preferably a 3- to 7-membered ring. Examples include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

[0180] Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferred. Examples of the cation (b2-1) include the following cations. TIFF2023118096000103.tif130162Examples of the cation (b2-2) include the following cations. TIFF2023118096000104.tif18150Examples of the cation (b2-3) include the following cations. TIFF2023118096000105.tif24126 Examples of the cation (b2-4) include the following cations. TIFF2023118096000106.tif120170

[0181] The acid generator (B) is a combination of the above-mentioned anions and the above-mentioned organic cations, which can be combined arbitrarily. Preferred examples of the acid generator (B) include a combination of an anion represented by any of formulas (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), and (B1a-35) to (B1a-41) with a cation (b2-1), (b2-2), (b2-3), or (b2-4).

[0182] Preferred examples of the acid generator (B) include those represented by formulas (B1-1) to (B1-60). Among these, those containing an arylsulfonium cation are preferred, and those represented by formulas (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), and (B1-31) to (B1-60) are particularly preferred. TIFF2023118096000107.tif208167

[0183] TIFF2023118096000108.tif235159

[0184] TIFF2023118096000109.tif238165

[0185] In the resist composition of the present invention, the content of the acid generator is preferably from 1 to 45 parts by mass, more preferably from 1 to 40 parts by mass, and even more preferably from 3 to 35 parts by mass, per 100 parts by mass of the resin (A). The resist composition of the present invention may contain one type of acid generator (B) alone, or may contain multiple types.

[0186] <Solvent (E)> The content of the solvent (E) in the resist composition is usually from 90 to 99.9% by mass, preferably from 92 to 99% by mass, and more preferably from 94 to 99% by mass. The content of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography. Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; etc. One type of solvent (E) may be used alone, or two or more types may be used.

[0187] <Quencher (C)> Examples of the quencher (C) include basic nitrogen-containing organic compounds and salts that generate an acid that is weaker in acidity than the acid generated from the acid generator. When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15 mass%, more preferably about 0.01 to 10 mass%, even more preferably about 0.1 to 8 mass%, and even more preferably about 0.1 to 7 mass%, based on the solids content of the resist composition. The basic nitrogen-containing organic compound includes amines and ammonium salts. The amines include aliphatic amines and aromatic amines. The aliphatic amines include primary amines, secondary amines, and tertiary amines.

[0188] Examples of amines include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributaryamine, benzophenone ... ethylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldi Decylamine, 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-pyridinyl)-2-methylpropanol, 2,2 ... 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, Examples thereof include 1,2-di(4-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'-dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, and bipyridine, preferably diisopropylaniline, and more preferably 2,6-diisopropylaniline.

[0189] Examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, choline, and the like.

[0190] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator is indicated by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator is a salt having an acid dissociation constant of the acid generated from the salt usually of -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator include a salt represented by the following formula, a salt represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. The salt that generates an acid with a lower acidity than the acid generated from the acid generator is preferably a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (a salt having a carboxylic acid anion), more preferably a weak acid inner salt (D), and even more preferably a diphenyliodonium salt containing a phenyl group substituted with a carboxylic acid anion among the weak acid inner salts (D). TIFF2023118096000110.tif95149

[0191] The weak acid inner salt (D) is preferably a diphenyliodonium salt having an iodonium cation to which two phenyl groups are bonded and a carboxylic acid anion substituted for at least one of the two phenyl groups bonded to the iodonium cation, and specifically includes salts represented by the following formulas.

[0192] TIFF2023118096000111.tif2362[In formula (D), R D1 and R D2 each independently represents a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 7 carbon atoms, an acyloxy group having 2 to 7 carbon atoms, an alkoxycarbonyl group having 2 to 7 carbon atoms, a nitro group, or a halogen atom. m' and n' each independently represent an integer of 0 to 4, and when m' is 2 or more, a plurality of R D1 may be the same or different, and when n' is 2 or more, a plurality of R D2 may be the same or different.] R D1 and R D2 Examples of the hydrocarbon group include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the chain hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, and nonyl groups. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and may be either saturated or unsaturated. Examples of the alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclononyl, and cyclododecyl, norbornyl, and adamantyl. Examples of aromatic hydrocarbon groups include aryl groups such as a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a 4-propylphenyl group, a 4-isopropylphenyl group, a 4-butylphenyl group, a 4-t-butylphenyl group, a 4-hexylphenyl group, a 4-cyclohexylphenyl group, an anthryl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of groups formed by combining these groups include alkyl-cycloalkyl groups, cycloalkyl-alkyl groups, and aralkyl groups (e.g., phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1-phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, and 6-phenyl-1-hexyl group). Examples of the alkoxy group include a methoxy group and an ethoxy group. Examples of the acyl group include an acetyl group, a propanoyl group, a benzoyl group, and a cyclohexanecarbonyl group. Examples of the acyloxy group include groups in which an oxy group (—O—) is bonded to the above-mentioned acyl group. Examples of the alkoxycarbonyl group include a group in which a carbonyl group (—CO—) is bonded to the above alkoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. 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 preferably an integer of 0 to 2, more preferably 0. When m' is 2 or more, multiple R D1 may be the same or different, and when n' is 2 or more, a plurality of R D2 may be the same or different.

[0193] More specifically, the following salts are included: TIFF2023118096000112.tif72165

[0194] <Other ingredients> The resist composition of the present invention may optionally contain components other than those described above (hereinafter, these may be 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, and dyes, can be used.

[0195] <Preparation of Resist Composition> The resist composition of the present invention can be prepared by mixing the resin (A) and acid generator (B), and, if necessary, a resin other than the resin (A), the solvent (E), the quencher (C), and other components (F). The order of mixing is arbitrary and is not particularly limited. The temperature during mixing can be selected from 10 to 40°C, depending on the type of resin, the solubility of the resin in the solvent (E), and other factors. The mixing time can be selected from 0.5 to 24 hours, depending on the mixing temperature. The mixing method is also not particularly limited, and stirring and mixing can be used. After mixing the components, it is preferable to filter the mixture using a filter with a pore size of about 0.003 to 0.2 μm.

[0196] <Method for producing a resist pattern> The method for producing a resist pattern of the present invention comprises the steps of: (1) applying the resist composition of the present invention onto a substrate; (2) drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) A step of developing the composition layer after heating is included. The resist composition can be applied to a substrate using a commonly used device such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers and organic substrates having a resist film formed on their surfaces. Before applying the resist composition, the substrate may be cleaned, and an anti-reflective film or the like may be formed on the substrate. The composition after coating is dried to remove the solvent and form a composition layer. Drying is carried out, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or by using a vacuum device. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 10 to 180 seconds. The pressure during vacuum drying is preferably 1 to 1.0 x 10 5 It is preferable that the pressure is about Pa. The resulting composition layer is typically exposed using an exposure machine. The exposure machine may be an immersion exposure machine. Various exposure light sources can be used, including those that emit ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), and F2 excimer laser (wavelength 157 nm); those that convert the wavelength of laser light from a solid-state laser source (such as a YAG or semiconductor laser) to emit harmonic laser light in the far ultraviolet or vacuum ultraviolet range; and those that irradiate with electron beams or extreme ultraviolet light (EUV). In this specification, irradiation with these types of radiation may be collectively referred to as "exposure." During exposure, exposure is typically performed through a mask corresponding to the desired pattern. When the exposure light source is an electron beam, exposure may be performed by direct writing 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 of the acid labile groups. 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 heated composition. Furthermore, before development, the steps of applying a resist composition, drying, exposing, and heating may be repeated on the composition layer after exposure. The heated composition layer is usually developed using a developer in a developing device. Development methods include dipping, puddling, spraying, and dynamic dispensing. The development temperature is preferably, for example, 5 to 60°C, and the development 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 produced. When a positive resist pattern is produced from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. Examples include aqueous solutions of tetramethylammonium hydroxide and (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline). The alkaline developer may also contain a surfactant. After development, the resist pattern is preferably washed with ultrapure water, and then water remaining on the substrate and pattern is removed. When a negative resist pattern is produced from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic developer") is used as the developer. Examples of organic solvents contained in organic developers include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; and aromatic hydrocarbon solvents such as anisole. The content of the organic solvent in the organic developer 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 these, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. The total content of butyl acetate and 2-heptanone in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant and a small amount of water. During development, development may be stopped by replacing the organic developer with a different type of solvent. The developed resist pattern is preferably washed with a rinse solution. There are no particular limitations on the rinse solution 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 cleaning, it is preferable to remove the rinse liquid remaining on the substrate and the pattern.

[0197] <Application> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, and is particularly suitable as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for semiconductor microfabrication. [Example]

[0198] The present invention will be explained in more detail with reference to examples. In the examples, "%" and "parts" representing the content or amount used are by mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography under the following conditions. Device: HLC-8120GPC model (Tosoh Corporation) Column: TSKgel Multipore H XL -M x 3 + guard column (Tosoh) Eluent: tetrahydrofuran Flow rate: 1.0mL / min Detector: RI detector Column temperature: 40℃ Injection volume: 100μl Molecular weight standard: Standard polystyrene (Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC: Agilent 1100, MASS: Agilent LC / MSD). In the following examples, the value of this molecular ion peak is indicated by "MASS."

[0199] Resin synthesis The compounds (monomers) used in the synthesis of the resin are shown below. TIFF2023118096000113.tif85158Hereinafter, these compounds will be referred to as "monomer (a1-2-6)" etc. according to their formula numbers.

[0200] Synthesis Example 1 [Synthesis of Resin A-1] Monomers (I-1), (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-2) were mixed in a molar ratio of 20:10:30:3:10:27 (monomer (I-1):monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-2)). 1.5 times the total mass of all monomers was mixed with methyl isobutyl ketone. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1.2 mol% and 3.6 mol%, respectively, and the mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered to give a resin with a weight-average molecular weight of approximately 5.5 × 10 3 Resin A-1 having the following structural units was obtained in a yield of 68%. TIFF2023118096000114.tif38164

[0201] Synthesis Example 2 [Synthesis of Resin A-2] Monomers (I-1), (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-13) were mixed in a molar ratio of 20:10:30:3:10:27 (monomer (I-1):monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-13). 1.5 times the total mass of all monomers was mixed with methyl isobutyl ketone. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1.2 mol% and 3.6 mol%, respectively, and the mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered, resulting in a resin with a weight-average molecular weight of approximately 5.4 × 10 3 Resin A-2 having the following structural units was obtained in a yield of 63%. TIFF2023118096000115.tif39163

[0202] Synthesis Example 3 [Synthesis of Resin A-3] Monomers (I-1), (a1-1-3), (a1-2-5), (a2-1-1), (a3-4-2), and (a1-4-2) were mixed in a molar ratio of 20:30:10:3:10:27 (monomer (I-1):monomer (a1-1-3):monomer (a1-2-5):monomer (a2-1-1):monomer (a3-4-2):monomer (a1-4-2)). 1.5 times the total mass of all monomers was mixed with methyl isobutyl ketone. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1.2 mol% and 3.6 mol%, respectively, and the mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered to give a resin with a weight-average molecular weight of approximately 5.5 × 10 3 Resin A-3 having the following structural units was obtained in a yield of 70%. TIFF2023118096000116.tif38164

[0203] Synthesis Example 4 [Synthesis of Resin A-4] Monomers (I-1), (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-13) were mixed in a molar ratio of 20:40:3:10:27 (monomer (I-1):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-13)). Methyl isobutyl ketone was added to the monomer mixture in an amount of 1.5 times the total weight of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators in amounts of 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount. The mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered, resulting in a resin with a weight-average molecular weight of approximately 5.7 × 10 3 Resin A-4 having the following structural units was obtained in a yield of 86%. TIFF2023118096000117.tif39140

[0204] Synthesis Example 5 [Synthesis of Resin A-5] Monomers (I-1), (a1-2-6), (a2-1-1), (a3-4-2), and (a1-4-2) were mixed in a molar ratio of 20:40:3:10:27 (monomer (I-1):monomer (a1-2-6):monomer (a2-1-1):monomer (a3-4-2):monomer (a1-4-2)). 1.5 times the total mass of all monomers, methyl isobutyl ketone, was then added to the resulting mixture. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators, at 1.2 mol% and 3.6 mol%, respectively, and the mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered, resulting in a resin with a weight-average molecular weight of approximately 5.8 × 10 3 Resin A-5 having the following structural units was obtained in a yield of 84%. TIFF2023118096000118.tif38141

[0205] Synthesis Example 6 [Synthesis of Resin A-6] Monomers (I-1), (a1-2-6), (a2-1-1), (a3-4-2), and (a1-4-19) were mixed in a molar ratio of 20:40:3:10:27 (monomer (I-1):monomer (a1-2-6):monomer (a2-1-1):monomer (a3-4-2):monomer (a1-4-19). Methyl isobutyl ketone was added to the monomer mixture in an amount of 1.5 times the total weight of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators in amounts of 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount. The mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times the mass of the total mass of all monomers was added an aqueous solution of p-toluenesulfonic acid (2.5 wt%), and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered to give a resin with a weight-average molecular weight of approximately 5.6 × 10 3 Resin A-6 having the following structural units was obtained in a yield of 80%. TIFF2023118096000119.tif38141

[0206] Synthesis Example 7 [Synthesis of Resin A-7] Monomers (I-9), (a1-2-6), (a2-1-1), (a3-4-2), and (a1-4-19) were mixed in a molar ratio of 20:40:3:10:27 (monomer (I-9):monomer (a1-2-6):monomer (a2-1-1):monomer (a3-4-2):monomer (a1-4-19). Methyl isobutyl ketone was added to the monomer mixture in an amount of 1.5 times the total weight of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators in amounts of 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount. The mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered, resulting in a resin with a weight-average molecular weight of approximately 5.4 × 10 3 Resin A-7 having the following structural units was obtained in a yield of 78%. TIFF2023118096000120.tif38154

[0207] Synthesis Example 8 [Synthesis of Resin A1-1] Monomer (I-1) was used as the monomer, and propylene glycol monomethyl ether acetate was mixed with this monomer in an amount twice the mass of the monomer. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in amounts of 1.65 mol% and 4.95 mol%, respectively, based on the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. The polymerization reaction solution was then poured into a large amount of a methanol / water mixed solvent to precipitate a resin, which was then filtered. The resulting resin was repulped in a methanol / water mixed solvent and filtered, resulting in a polymer with a weight-average molecular weight of approximately 8.0 x 10. 3 Resin A1-1 having the following structural units was obtained in a yield of 70%. TIFF2023118096000121.tif2852

[0208] Synthesis Example 9 [Synthesis of Resin A1-2] Monomer (I-4) was used as the monomer, and propylene glycol monomethyl ether acetate was mixed with this monomer in an amount twice the mass of the monomer. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in amounts of 1.55 mol% and 4.65 mol%, respectively, based on the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. The polymerization reaction solution was then poured into a large amount of a methanol / water mixed solvent to precipitate a resin, which was then filtered. The resulting resin was repulped in a methanol / water mixed solvent and filtered, resulting in a polymer with a weight-average molecular weight of approximately 6.7 x 10. 3 Resin A1-2 having the following structural units was obtained in a yield of 86%. TIFF2023118096000122.tif2849

[0209] Synthesis Example 10 [Synthesis of Resin A1-3] Monomer (I-9) was used as the monomer, and propylene glycol monomethyl ether acetate was mixed with this monomer in an amount twice the mass of the monomer. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to the resulting mixture in amounts of 1.65 mol% and 4.95 mol%, respectively, based on the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. The polymerization reaction solution was then poured into a large amount of a methanol / water mixed solvent to precipitate a resin, which was then filtered. The resulting resin was repulped in a methanol / water mixed solvent and filtered, resulting in a polymer with a weight-average molecular weight of approximately 7.6 x 10. 3 Resin A1-3 having the following structural units was obtained in a yield of 66%. TIFF2023118096000123.tif3067

[0210] Synthesis Example 11 [Synthesis of Resin A2-1] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-2) were mixed in a molar ratio of 20:35:3:15:27 (monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-2)). This monomer mixture was then mixed with 1.5 times the total mass of all monomers of methyl isobutyl ketone. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1.2 mol% and 3.6 mol%, respectively, and the mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered, resulting in a resin with a weight-average molecular weight of approximately 5.3 × 10 3 Resin A2-1 having the following structural units was obtained in a yield of 63%. TIFF2023118096000124.tif38159

[0211] Synthesis Example 12 [Synthesis of Resin A2-2] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-13) were mixed in a molar ratio of 20:35:3:15:27 (monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-13)). Methyl isobutyl ketone was added to the monomer mixture in an amount of 1.5 times the total weight of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators in amounts of 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount. The mixture was heated at 73°C for approximately 5 hours. Then, to the polymerization reaction solution, 2.0 times by mass of p-toluenesulfonic acid aqueous solution (2.5 wt%) relative to the total mass of all monomers was added, and after stirring for 12 hours, the layers were separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate a resin, which was then filtered and recovered, resulting in a resin with a weight-average molecular weight of approximately 5.1 × 10 3 Resin A2-2 having the following structural units was obtained in a yield of 61%. TIFF2023118096000125.tif38159

[0212] Synthesis Example 13 [Synthesis of Resin A2-3] Monomers (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-2) were used as monomers, and the molar ratio [monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-2)] was mixed at a ratio of 55:3:15:27. Furthermore, 1.5 times the mass of methyl isobutyl ketone based on the total mass of all monomers was added to this monomer mixture. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. Subsequently, 2.0 times the mass of the total mass of all monomers in aqueous p-toluenesulfonic acid solution (2.5 wt%) was added to the polymerization reaction solution, stirred for 12 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to obtain a resin with a weight-average molecular weight of approximately 5.5 × 10 3 Resin A2-3 having the following structural units was obtained in a yield of 86%. TIFF2023118096000126.tif38133

[0213] Synthesis Example 14 [Synthesis of Resin A2-4] Monomers (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-13) were used as monomers, and the molar ratio [monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-13)] was mixed at a ratio of 55:3:15:27. Furthermore, 1.5 times the mass of methyl isobutyl ketone based on the total mass of all monomers was added to this monomer mixture. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. Subsequently, 2.0 times the mass of the total mass of all monomers in aqueous p-toluenesulfonic acid solution (2.5 wt%) was added to the polymerization reaction solution, stirred for 12 hours, and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to obtain a resin with a weight-average molecular weight of approximately 5.4 × 10 3 Resin A2-4 having the following structural units was obtained in a yield of 82%. TIFF2023118096000127.tif38133

[0214] Synthesis Example 15 [Synthesis of Resin A2-5] Monomers (a1-2-6), (a2-1-3), (a3-4-2), and (a1-4-19) were used as monomers, and the molar ratio [monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (a1-4-19)] was mixed at a ratio of 55:3:15:27. Furthermore, 1.5 times the mass of methyl isobutyl ketone was added to this monomer mixture, based on the total mass of all monomers. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators, at 1.2 mol% and 3.6 mol%, respectively, based on the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. Subsequently, 2.0 times the mass of the total mass of all monomers, based on the total mass of all monomers, of an aqueous p-toluenesulfonic acid solution (2.5 wt%) was added to the polymerization reaction solution, and the mixture was stirred for 12 hours and then separated. The recovered organic layer was poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to obtain a resin with a weight-average molecular weight of approximately 5.3 × 10 3 Resin A2-5 having the following structural units was obtained in a yield of 80%. TIFF2023118096000128.tif38133

[0215] Synthesis Example 16 [Synthesis of Resin AX1] Monomers (a1-1-3), (a1-2-5), (a2-1-1), (a3-4-2), and (I-1) were mixed in a molar ratio of 45:14:4:33:4 (monomer (a1-1-3):monomer (a1-2-5):monomer (a2-1-1):monomer (a3-4-2):monomer (I-1)). A solution was then prepared by adding propylene glycol monomethyl ether acetate in an amount 1.5 times the total monomer mass. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1 mol% and 3 mol%, respectively, relative to the total monomer mass. The mixture was heated at 75°C for approximately 5 hours. The resulting reaction mixture was poured into a large amount of a methanol / water mixed solvent to precipitate a resin, which was then filtered. The resin thus obtained was stirred in methanol and filtered to obtain a resin having a weight-average molecular weight of 8.3 × 10 3 Resin AX1 (copolymer) was obtained in a yield of 74%. This resin AX1 has the following structural units. TIFF2023118096000129.tif39149

[0216] Synthesis Example 17 [Synthesis of Resin AX2] Monomers (a1-1-3), (a1-2-5), (a2-1-1), (a3-4-2), and (I-4) were mixed in a molar ratio of 45:14:4:33:4 (monomer (a1-1-3):monomer (a1-2-5):monomer (a2-1-1):monomer (a3-4-2):monomer (I-4)). A solution was then prepared by adding propylene glycol monomethyl ether acetate in an amount 1.5 times the total monomer mass. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators at 1 mol% and 3 mol%, respectively, relative to the total monomer mass. The mixture was heated at 75°C for approximately 5 hours. The resulting reaction mixture was poured into a large amount of a methanol / water mixed solvent to precipitate a resin, which was then filtered. The resin thus obtained was stirred in methanol and filtered to obtain a resin having a weight average molecular weight of 8.6×10 3Resin AX2 (copolymer) was obtained in a yield of 68%. This resin AX2 has the following structural units. TIFF2023118096000130.tif39149

[0217] <Preparation of Resist Composition> The components shown in Table 1 were mixed and dissolved to obtain a mixture, which was then filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a resist composition. [Table 1]

[0218] <Resin> A-1~A-7, A1-1~A1-3, A2-1~A2-5, AX1, AX2: Resin A-1~Resin A-7, Resin A1-1~Resin A1-3, Resin A2-1~Resin A2-5, Resin AX1, Resin AX2 <Acid generator (B)> B1-43: Salt represented by formula (B1-43) (synthesized according to the examples in JP 2016-47815 A) TIFF2023118096000132.tif4382<Quencher (C)> C1: Synthesized by the method described in JP 2011-39502 A TIFF2023118096000133.tif4247<solvent> Propylene glycol monomethyl ether acetate 400 parts Propylene glycol monomethyl ether 100 parts γ-butyrolactone 5 parts

[0219] (Electron beam exposure evaluation of resist composition: butyl acetate 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 onto this silicon wafer so that the composition layer had a thickness of 0.04 μm. The wafer was then pre-baked on a direct hot plate at the temperature shown in the "PB" column in Table 1 for 60 seconds to form a composition layer. A line and space pattern was directly written onto the composition layer formed on the wafer using an electron beam lithography machine ("HL-800D 50 keV" manufactured by Hitachi, Ltd.) by gradually changing the exposure dose. After exposure, post-exposure baking was performed on a hot plate for 60 seconds at the temperature shown in the "PEB" column in Table 1. Next, the composition layer on this silicon wafer was developed by a dynamic dispensing method using butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a developer at 23°C for 20 seconds to obtain a resist pattern. The resulting resist pattern (line and space pattern) was observed under a scanning electron microscope, and the exposure amount at which the line width and space width of the 60 nm line and space pattern became 1:1 was taken as the effective sensitivity.

[0220] Line edge roughness evaluation (LER): The fluctuation of the unevenness of the sidewall surface of the resist pattern produced at the effective sensitivity was measured using a scanning electron microscope to determine the line edge roughness. The results are shown in Table 2. [Table 2] [Industrial Applicability]

[0221] The resist composition of the present invention provides resist patterns with excellent line edge roughness (LER), making it suitable for semiconductor microfabrication and extremely useful industrially.

Claims

1. an acid generator; one or more resins, At least one resin among the one or more resins contains a structural unit represented by formula (I), A resist composition, wherein at least one resin among the one or more resins includes a structural unit represented by formula (a2-A). [In formula (I), R １ represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R Ａ are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1, provided that the sum of s1 and t1 is 1 or 2. L １２ 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-, -CO- or -SO ２ - may be replaced by . [In formula (a2-A), R a50 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a50 is a single bond or *-X a51 - (A a52 -X a52 ) nｂ -, * represents -R a50 represents the bonding site with the carbon atom to which it is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents —O—, —CO—O—, or —O—CO—. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, a plurality of R a51 may be the same or different.]

2. 2. The resist composition according to claim 1, wherein one of the one or more resins comprises a structural unit having an acid labile group other than the structural unit represented by formula (I).

3. 3. The resist composition according to claim 2, wherein the structural unit having an acid labile group other than the structural unit represented by formula (I) comprises at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), and a structural unit represented by formula (a1-2): [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 group combining these. 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. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1′ represents an integer of 0 to 3.

4. 2. The resist composition according to claim 1, comprising a resin containing the structural unit represented by formula (I) and the structural unit represented by formula (a2-A).

5. a resin containing a structural unit represented by formula (I); 4. The resist composition according to claim 3, comprising a resin containing the structural unit represented by formula (a2-A) and at least one structural unit selected from the group consisting of the structural unit represented by formula (a1-0), the structural unit represented by formula (a1-1), and the structural unit represented by formula (a1-2).

6. 6. The resist composition according to claim 5, wherein the content of the structural unit represented by formula (I) in the resin containing the structural unit represented by formula (I) is 30 to 100 mol % based on all structural units.

7. 4. The resist composition according to claim 3, comprising a resin containing the structural unit represented by formula (I), the structural unit represented by formula (a2-A), and at least one structural unit selected from the group consisting of the structural unit represented by formula (a1-0), the structural unit represented by formula (a1-1), and the structural unit represented by formula (a1-2).

8. 2. The resist composition according to claim 1, wherein the acid generator comprises a salt represented by formula (B1): [In formula (B1), Q ｂ１ and Q ｂ２ 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. L ｂ１ represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, and —CH ２ The - may be replaced by -O- or -CO-, and the hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted by a fluorine atom or a hydroxy group. Y represents an optionally substituted methyl group or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, and —CH ２ - is -O-, -S-, -SO ２ It may be replaced by - or -CO-. Z1 ＋ represents an organic cation.

9. 2. The resist composition according to claim 1, further comprising a salt that generates an acid that is weaker in acidity than the acid generated from said acid generator.

10. (1) a step of applying the resist composition according to any one of claims 1 to 9 onto a substrate; (2) a step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) a step of heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising:

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