Resist composition and method for producing resist pattern

Abstract

To provide a resist composition capable of producing a resist pattern having good line edge roughness.SOLUTION: The resist composition contains a resin containing a structural unit derived from a compound represented by a specific structure and a structural unit represented by formula (a1-2), an acid generator, and a carboxylate salt generating an acid weaker in acidity than an acid generated from the acid generator. [In the formulae, La2 represents -O - or the like; Ra7 represents an alkyl group, an alkenyl group, an alicyclichydrocarbon group, or the like; n1 represents an integer of 0 to 10; and n1 ' represents an integer of 0 to 3.]. ] 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 that includes a structural unit derived from the following compound: TIFF2026001162000001.tif3822 Patent Document 2 describes a resist composition containing a resin that includes a structural unit derived from the following compound. TIFF2026001162000002.tif2624 [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-069612 [Patent Document 2] Japanese Patent Application Publication No. 2018-205710 Summary of the Invention [Problem to be solved by the invention]

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

[0005] The present invention includes the following inventions. [1] A compound represented by formula (I). TIFF2026001162000003.tif7949 [In formula (I), R 1represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A 1 and A 2 each independently represents a single bond or an alkanediyl group having 1 to 6 carbon atoms. W represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. X 1 -CO-O-*, -O-*, -O-CO-*, -O-CO-(CH2) mm -O-* or -O-(CH2) nn -CO-O-* (* represents the bonding site with Ar). mm and nn represent 0 or 1. Ar represents an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent. R 2 each independently represents a hydrogen atom or an acid labile group, or R 2 When there are two or more R 2 may be combined together to form a group having an acetal ring structure. n represents an integer of 1 to 3. When n is an integer of 2 or more, a plurality of R 2 may be the same or different from each other.] [2] In formula (I), A 1 and A 2 is a single bond. [3] In formula (I), X 1 is —CO—O—* (* represents the bonding site with Ar). [4] The compound according to any one of [1] to [3], wherein in formula (I), n is 1 or 2. [5] In formula (I), R 2 The compound according to any one of [1] to [4], wherein the acid labile group is a group represented by formula (1a) or a group represented by formula (2a). TIFF2026001162000004.tif2287 [In formula (1a), R aa1, R aa2 and R aa3 may each independently have a substituent. represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms which may have a substituent, an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, or R aa1 and R aa2 are mutually They combine with the carbon atom to which they are bonded to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms. naa represents 0 or 1. * denotes a binding site.] TIFF2026001162000005.tif2060[In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa2’ and R aa3’ are bonded to each other and they combine -CX a - and carbon number 3 to 20 It forms a heterocyclic group, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-. X a represents an oxygen atom or a sulfur atom. * denotes a binding site.] [6]R 2 is a hydrogen atom, or n is 2 or more and two or more R 2 Two of the R 2 The compound according to any one of [1] to [5], wherein [7] In formula (I), n is 2 and two R 2 and each represent a hydrogen atom. [8] In formula (I), n is 2 or more, and two or more R 2 Of these, two R 2 [6] The compound according to [6], wherein together form a group having an acetal ring structure. [9] The compound according to any one of [1] to [8], wherein, in formula (I), Ar represents a benzenediyl group.

[10] In formula (I), n is 2 and two -OR 2 are respectively, X 1 The compound according to [9], wherein the benzenediyl group is bonded to the meta and ortho positions of the

[11] A resin containing a structural unit derived from the compound according to any one of [1] to

[10] .

[12] The resin according to

[11] , further comprising a structural unit represented by formula (a2-A). TIFF2026001162000006.tif4551[In formula (a2-A), R a50 is a hydrogen atom, a halogen atom, or a group having 1 to 6 carbon atoms which may have a halogen atom represents an alkyl group represented by the formula: R a51 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a It represents an alkoxy group, 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, multiple R in Numbers a51 may be the same or different from each other.]

[13] The resin according to

[11] or

[12] , further comprising a structural unit having an acid labile group different from the structural unit derived from the compound represented by formula (I).

[14] The resin according to

[13] , wherein the resin containing a structural unit having an acid labile group different from the structural unit derived from the compound represented by formula (I) is a resin containing at least one selected from the group consisting of a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2): TIFF2026001162000007.tif4398 [In formula (a1-1) and formula (a1-2), 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 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 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 combination thereof. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

[15] A resist composition comprising the resin according to any one of

[11] to

[14] and an acid generator.

[16] The resist composition according to

[15] , further comprising a salt that generates an acid that is weaker in acidity than the acid generated from the acid generator.

[17] (1) A step of applying the resist composition according to

[15] or

[16] 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 method for producing a resist pattern, comprising the step of developing the composition layer after heating. [Effects of the Invention]

[0006] By using a resist composition that uses a resin that includes a structural unit derived from the compound 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, the term "(meth)acrylic monomer" refers to a monomer having a structure such as "CH2=CH-CO-" and monomers having the structure "CH2=C(CH3)-CO-". Similarly, "(meth)acrylate" and "(meth)acrylic acid" respectively mean "at least one selected from the group consisting of acrylates and methacrylates" and "at least one selected from the group consisting of acrylic acid and methacrylic acid". "CH2=C(CH3)-CO-" or "CH2=CH-C When a structural unit having "O-" is exemplified, structural units having both groups are also exemplified. The examples are intended to be illustrative. Furthermore, for groups described herein that can have both a linear structure and a branched structure, either may be used. When stereoisomers exist, all stereoisomers are included. "Derived from" or "derived" refers to a polymerizable C=C bond contained in the molecule becoming a -CC- group by polymerization. "Combined group" refers to a group in which two or more of the exemplified groups are combined with their valences appropriately changed. 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] <Compound (I)> The compound of the present invention is a compound represented by formula (I) (hereinafter, sometimes referred to as "compound (I)"). TIFF2026001162000008.tif7949 [In formula (I), all symbols have the same meanings as defined above.] R 1 Examples of the halogen atom in R include a fluorine atom, a chlorine atom, and a bromine atom. 1 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 1 is more preferably a hydrogen atom or a methyl group, and even more preferably a methyl group.

[0009] A 1 and A 2 Examples of the alkanediyl group having 1 to 6 carbon atoms 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 linear alkanediyl groups having an alkyl group (particularly, an alkyl group having 1 to 4 carbon atoms such as a methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, and tert-butyl group) as a side chain, specifically branched alkanediyl groups such as ethane-1,1-diyl, propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl. A 1 and A 2 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms, more preferably a single bond or a methyl group, and even more preferably a single bond.

[0010] Examples of the alicyclic hydrocarbon group having 3 to 18 carbon atoms for W include monocyclic or polycyclic saturated alicyclic hydrocarbon groups, such as those shown below. The bonding site can be at any position. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12, and even more preferably 3 to 10. TIFF2026001162000009.tif41166Specific examples of monocyclic divalent alicyclic saturated hydrocarbon groups include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. The alicyclic saturated hydrocarbon group preferably has 3 to 16 carbon atoms, and more preferably 3 to 12 carbon atoms.

[0011] Examples of the substituent on the alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by W include a hydroxy group, a cyano group, a carboxyl group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an acyl group having 2 to 13 carbon atoms, an acyloxy group having 2 to 13 carbon atoms, and a group formed by combining two or more of these groups. Examples of the alkyl group having 1 to 12 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, octyl group, nonyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 9, and more preferably 1 to 4. Examples of the alkoxy group having 1 to 12 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group. Examples of the acyl group having 2 to 13 carbon atoms include an acetyl group, a propionyl group, and a butyryl group. Examples of the acyloxy group having 2 to 13 carbon atoms include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by W may have one or more substituents.

[0012] The -CH2- contained in the alicyclic hydrocarbon group having 3 to 18 carbon atoms of W is -O-, -S-, - It may be replaced by CO- or -SO2-. When the alicyclic hydrocarbon group of 3 to 18 carbon atoms represented by W has a substituent, or when a -CH2- group contained in the alicyclic hydrocarbon group has been replaced with -O-, -S-, -CO-, or -SO2-, the number of carbon atoms in the hydrocarbon group before the replacement is defined as the number of carbon atoms in the hydrocarbon group. Examples of groups in which a -CH2- group contained in the alicyclic hydrocarbon group of 3 to 18 carbon atoms represented by W has been replaced with -O-, -S-, CO-, or -SO2- include the following groups. The bonding site can be at any position. TIFF2026001162000010.tif47158Specific examples include groups having a lactone skeleton such as nobornane 2,6-lactone, and groups having a thiolactone skeleton such as nobornane 2,6-thiolactone. W is preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), and more preferably an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-).

[0013] Examples of the divalent aromatic hydrocarbon group represented by Ar include a benzenediyl group, a naphthalenediyl group, an anthracenediyl group, etc. The divalent aromatic hydrocarbon group represented by Ar is preferably a benzenediyl group. Examples of the trivalent or tetravalent aromatic hydrocarbon group represented by Ar include a benzenetriyl group, a benzenetetrayl group, a naphthalenetriyl group, a naphthalenetetrayl group, an anthracenetriyl group, and an anthracenetetrayl group. The aromatic hydrocarbon group of Ar preferably has 6 to 24 carbon atoms, more preferably 6 to 18 carbon atoms, even more preferably 6 to 14 carbon atoms, even more preferably 6 to 10 carbon atoms, and even more preferably 6 carbon atoms. Ar may have a substituent not shown in formula (I). 2 Examples of the substituent other than the above include a halogen atom, a cyano group, an alkyl group having 1 to 16 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced by —O— or —CO—), Fluorinated alkyl group 12 (-CH2- contained in the fluorinated alkyl group is -O- or -C O-), an alicyclic hydrocarbon group having 3 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a group combining these groups. Examples of the halogen atom as a substituent of Ar include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group having 1 to 16 carbon atoms as a substituent for Ar include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 9, even more preferably 1 to 6, and still more preferably 1 to 4. The -CH2- in the alkyl group of the substituent of Ar is replaced with -O- or -CO-. In the case where -CH2- in an alkyl group is replaced with -O- or -CO-, the number of carbon atoms before the replacement is the total number of carbon atoms in the alkyl group. a carboxyl group (an ethyl group in which -CH2- is replaced with -O-) -CH2-CH2- in the above is replaced with -O-CO-), alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), alkoxy Carbonyl 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-), alkylcarbonyloxy group (a group in which (a group in which any one of -CH2-CH2- at any position contained therein is replaced with -CO-O-) The alkoxy group of the substituent of Ar includes an alkoxy group having 1 to 15 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, dodecyloxy group, etc. The number of carbon atoms in the alkoxy group of the substituent of Ar is preferably 1 to 12, more preferably 1 to 11, even more preferably 1 to 6, and even more preferably 1 to 4. The alkoxycarbonyl group, alkylcarbonyl group and alkylcarbonyloxy group as the substituents of Ar represent groups in which a carbonyl group or a carbonyloxy group is bonded to the above-mentioned alkyl group or alkoxy group. The alkoxycarbonyl group as a substituent for Ar includes an alkoxycarbonyl group having 2 to 15 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. The alkylcarbonyl group as a substituent for Ar includes an alkoxycarbonyl group having 2 to 15 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyloxy group as a substituent for Ar includes an alkylcarbonyloxy group having 2 to 15 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkoxycarbonyl group as a substituent for Ar is preferably 2 to 13, more preferably 2 to 11, even more preferably 2 to 6, and even more preferably 2 to 4. The number of carbon atoms in the alkylcarbonyl group as a substituent for Ar is preferably 2 to 13, more preferably 2 to 12, even more preferably 2 to 6, and even more preferably 2 to 4. The alkylcarbonyloxy group of the substituent of Ar preferably has 2 to 13 carbon atoms, more preferably 2 to 11 carbon atoms, even more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms. Examples of the fluorinated alkyl group having 1 to 12 carbon atoms as a substituent for Ar include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, etc. The number of carbon atoms in the fluorinated alkyl group as a substituent for Ar is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4. The -CH2- contained in the fluoroalkyl group of the Ar substituent is replaced with -O- or -CO-. If the fluorinated alkyl group is substituted, the number of carbon atoms before the substitution is the total number of carbon atoms of the fluorinated alkyl group. The groups that have been used include fluorinated alkoxy groups (groups in which -CH2- at any position in a fluorinated alkyl group is replaced with -O-), fluorinated alkoxycarbonyl groups (groups in which a fluorinated alkyl group a fluorinated alkylcarbonyl group (wherein any -CH2-CH2- at any position in the alkyl group is replaced with -CO- substituted with -CO-O-), and a fluorinated alkylcarbonyloxy group (a group in which any -CH2-CH2- at any position contained in a fluorinated alkyl group is replaced with -CO-O-). The fluorinated alkoxy group, fluorinated alkoxycarbonyl group, fluorinated alkylcarbonyl group, and fluorinated alkylcarbonyloxy group of the substituent of Ar include a fluorinated alkoxy group having 1 to 11 carbon atoms, a fluorinated alkoxycarbonyl group having 2 to 11 carbon atoms, a fluorinated alkylcarbonyl group having 2 to 12 carbon atoms, and a fluorinated alkylcarbonyloxy group having 2 to 11 carbon atoms, and one or more hydrogen atoms of the above-exemplified groups may be replaced with a fluorine atom. The alicyclic hydrocarbon group having 3 to 12 carbon atoms as a substituent for Ar may be either monocyclic or polycyclic, and examples include the groups shown below: ** indicates the bonding site to the aromatic hydrocarbon group. Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms as the substituent of TIFF2026001162000011.tif16157Ar include a phenyl group and a naphthyl group. Examples of the combined group in the substituent of Ar include a group combining a hydroxy group with an alkyl group having 1 to 12 carbon atoms, a group combining an alkoxy group having 1 to 12 carbon atoms with an alkoxy group having 1 to 12 carbon atoms, and a group combining an alkyl group having 1 to 12 carbon atoms with an aromatic hydrocarbon group having 6 to 10 carbon atoms. Examples of the substituent of Ar, which is a combination of a hydroxy group and an alkyl group having 1 to 12 carbon atoms, include hydroxyalkyl groups having 1 to 12 carbon atoms, such as a hydroxymethyl group and a hydroxyethyl group. Examples of the substituent of Ar, which is a combination of an alkoxy group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms, include an alkoxyalkoxy group having 2 to 24 carbon atoms such as an ethoxyethoxy group. Examples of the substituent of Ar, which is a combination of an alkyl group having 1 to 12 carbon atoms and an aromatic hydrocarbon group having 6 to 10 carbon atoms, include aralkyl groups having 7 to 22 carbon atoms such as a benzyl group. The substituent of Ar is -OR 2 Besides these, a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 11 carbon atoms, an alkoxycarbonyl group having 2 to 11 carbon atoms, an alkylcarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyloxy group having 2 to 11 carbon atoms is preferred, a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 11 carbon atoms, an alkoxycarbonyl group having 2 to 11 carbon atoms, an alkylcarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyloxy group having 2 to 11 carbon atoms is more preferred, and a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 11 carbon atoms is even more preferred. Ar is -OR 2 In addition to the above, the aromatic hydrocarbon group is preferably an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent, more preferably an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably an aromatic hydrocarbon group having 6 to 18 carbon atoms.

[0014] R 2 The acid labile group in R 2 When a group represented by the following formula (I) is eliminated, a hydroxy group is formed. R of the structural unit (I) used in the production of resin (A) 2 is an acid labile group, the resin (A) can be converted to R 2 Desorption (R 2 may be converted into hydrogen atoms), and the elimination rate is preferably 40% to 100%, more preferably 60% to 100%, and even more preferably 100%. Examples of the acid labile group include a group represented by formula (1a) (hereinafter sometimes referred to as "acid labile group (1a)") and a group represented by formula (2a) (hereinafter sometimes referred to as "acid labile group (2a)"). TIFF2026001162000012.tif2287 [In formula (1a), R aa1 , R aa2 and R aa3 may each independently have a substituent. represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms which may have a substituent, an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, or R aa1 and R aa2 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. naa represents 0 or 1. * indicates the bonding site with the oxygen atom bonded to Ar.] TIFF2026001162000013.tif2060[In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa2’ and R aa3’ are bonded to each other and they combine -CX a - and carbon number 3 to 20 It forms a heterocyclic group, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-. X a represents an oxygen atom or a sulfur atom. * indicates the bonding site with the oxygen atom bonded to Ar.]

[0015] R aa1 , R aa2 and R aa3 The alkyl group includes methyl, ethyl, propyl, n n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, etc. aa1 , R aa2 and R aa3 The alkyl group preferably has 1 to 6 carbon atoms, More preferably, it is 1 to 3. R aa1 , R aa2 and R aa3 Examples of the alkenyl group include an ethenyl group, a propenyl group, an isoprenyl group, and an aryl group. Examples of such groups include a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octynyl group, an isooctynyl group, and a nonenyl group. R aa1 , R aa2 and R aa3 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 the bonding site with the oxygen atom bonded to Ar): R aa1 , R aa2 and R aa3 The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, and more preferably is 3 to 12. TIFF2026001162000014.tif9159R aa1 , R aa2 and R aa3 Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an aryl group, and an aryl group. Examples of aryl groups include tolyl, biphenyl, and phenanthryl groups. aa1 , R aa2 and R aa3 The aromatic hydrocarbon group preferably has 6 to 14 carbon atoms, and more preferably It is 6 to 10.

[0016] R aa1 , Raa2 and R aa3 The alkyl group having 1 to 8 carbon atoms may have a substituent. Examples of the group include alkenyl groups having 2 to 8 carbon atoms, alicyclic hydrocarbon groups having 3 to 20 carbon atoms, and aromatic hydrocarbon groups having 6 to 18 carbon atoms. Examples of the substituent of the alkenyl group having 2 to 8 carbon atoms, which may have a substituent, include alkyl groups having 1 to 8 carbon atoms, alicyclic hydrocarbon groups having 3 to 20 carbon atoms, and aromatic hydrocarbon groups having 6 to 18 carbon atoms. Examples of the substituent of the alicyclic hydrocarbon group having 3 to 20 carbon atoms, which may have a substituent, include alkyl groups having 1 to 8 carbon atoms, alkenyl groups having 2 to 8 carbon atoms, and aromatic hydrocarbon groups having 6 to 18 carbon atoms. Examples of the substituent of the aromatic hydrocarbon group having 6 to 18 carbon atoms, which may have a substituent, include alkyl groups having 1 to 8 carbon atoms, alkenyl groups having 2 to 8 carbon atoms, and alicyclic hydrocarbon groups having 3 to 20 carbon atoms. More specifically, groups combining the above-mentioned alkyl groups with alicyclic hydrocarbon groups (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, and norbornylethyl 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. naa is preferably 1.

[0017] R aa1 and R aa2 -C(R aa1 )( R aa2 )(R aa3) includes the following groups. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12. * represents the bonding site with the oxygen atom bonded to Ar. TIFF2026001162000015.tif33153

[0018] The group represented by formula (1a) is a 1,1-dialkylalkoxycarbonyl group (R aa1 , R aa2 and R aa is an alkyl group, preferably a tert-butoxycarbonyl group), a 2-alkyladamantan-2-yloxycarbonyl group (in formula (1a), R aa1 , R aa2 and the carbon atoms to which they are bonded form an adamantyl group, and R aa3 is an alkyl group) and 1-(adamantan-1-yl)-1-alkylalkoxy a carbonyl group (in formula (1a), R aa1 and R aa2 is an alkyl group, and R aa3 Adamant a methyl group).

[0019] R aa1' , R aa2' and R aa3' Examples of the hydrocarbon group include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. The alkyl group and the alicyclic hydrocarbon group are represented by R aa1 , R aa2 and R aa Examples of the groups include the same groups as those listed in the 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 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. R aa2' and R aa3' are bonded to each other and the carbon atoms to which they are bonded and X a together with heterocycles When forming a group, -C(R aa1' )(R aa2' )-X a -(R aa3' ) are the following groups: * represents the bonding site with the oxygen atom bonded to Ar. TIFF2026001162000016.tif22149R aa1' and R aa2' At least one of these is preferably a hydrogen atom.

[0020] Specific examples of the acid labile group (1a) include the following groups: * represents a bonding site. TIFF2026001162000017.tif66163

[0021] Specific examples of the acid labile group (2a) include the following groups: * represents the bonding site with the oxygen atom bonded to Ar. TIFF2026001162000018.tif85159 In the structural unit (I), multiple R 2 may be the same or different.

[0022] The Two R's 2 When these are taken together to form a group having an acetal ring structure, *-(R 2 Examples of 2 include a group represented by formula (3a) (hereinafter sometimes referred to as "group (3a)"). TIFF2026001162000019.tif19149 [In formula (3a), R ab1 and R ab2 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or R ab1 and R ab2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded, and -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced with -O- or -CO-. * indicates the bonding site with each of the two oxygen atoms bonded to Ar.] The alkyl group and the alicyclic hydrocarbon group include R aa1 , R aa2 and R aa3 Similar to the groups listed in Examples of the group include the following. Examples of the group (3a) include the groups represented by the following formulas: * represents the bonding site with each of the two oxygen atoms bonded to Ar. TIFF2026001162000020.tif17110

[0023] Also, two R 2 When these are taken together to form a group having an acetal ring structure, *-Ar―(OR 2 ) 2 is a group represented by the following formula (wherein Ar is a benzenediyl group, and the benzene ring is **-OR 2 Here, ** represents the bonding site with Ar. ) and the like. * represents X 1 represents the binding site with TIFF2026001162000021.tif36153

[0024] n is preferably 1 or 2, and more preferably 2. R 2 The acid labile group in the formula (2a) is preferably a group represented by formula (2a). R 2 is a hydrogen atom or a group represented by formula (2a), or n is 2 or more and two or more R 2 Two of the R 2 are preferably hydrogen atoms or n is 2 or more and two R 2 More preferably, when n is 2, two R 2 are each a hydrogen atom, or n is 2, and Ar is a benzenediyl group, two -OR 2 are X respectively. 1 It is even more preferable that the benzenediyl group is bonded to the meta and ortho positions relative to the benzenediyl group. X 1 is preferably -CO-O-*, -O-* or -O-CO-*, and more preferably -CO-O-* or -O-*. Resin (A) is R 2 When the structural unit (I) is a hydrogen atom, R 2 The amount of structural units (I) in which is a hydrogen atom is preferably 40 to 100 mol %, more preferably 60 to 100 mol %, and even more preferably 100 mol %, based on the total amount of structural units (I).

[0025] Examples of compound (I) include the following. TIFF2026001162000022.tif237160

[0026] TIFF2026001162000023.tif240160

[0027] TIFF2026001162000024.tif250162

[0028] TIFF2026001162000025.tif240163

[0029] TIFF2026001162000026.tif212160

[0030] TIFF2026001162000027.tif107159

[0031] In the compounds represented by formula (I-1) to formula (I-86), R 1 The equivalent Compounds in which the ethyl group is replaced by a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom are also included as Compound (I).

[0032] <Method for producing compound (I)> Compound (I) can be obtained by reacting a compound represented by formula (Ia) with a compound represented by formula (Ib) in the presence of a catalyst in a solvent. TIFF2026001162000028.tif72151 [wherein all symbols have the same meanings as above] Examples of the solvent include methyl isobutyl ketone, chloroform, tetrahydrofuran, and toluene. Examples of the catalyst include basic catalysts such as pyridine, dimethylaminopyridine, N-methylpiperidine, N-methylpyrrolidine, and potassium hydroxide, and carbonyldiimidazole. Examples of the compound represented by formula (Ia) include salts represented by the following formula, which are readily available on the market. TIFF2026001162000029.tif32133 Examples of the compound represented by formula (Ib) include salts represented by the following formula, which are readily available on the market and can also be easily produced by known production methods. TIFF2026001162000030.tif40138

[0033] [Resin A] The resin of the present invention is a resin (hereinafter sometimes referred to as "resin (A)") containing a structural unit derived from compound (I) (hereinafter sometimes referred to as "structural unit (I)"). Resin (A) may be a homopolymer consisting of only one type of structural unit (I), a copolymer consisting of two or more types of structural units (I), or a polymer containing one or more structural units other than structural unit (I). The structural unit other than structural unit (I) may be a structural unit having an acid labile group other than structural unit (I) (hereinafter sometimes referred to as "structural unit (a1)"). Examples of the acid labile group include a structural unit other than the structural unit having an acid labile group and having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit not having an acid labile group (hereinafter sometimes referred to as "structural unit (s)"), and a structural unit having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"). Here, the acid labile group refers to a group that has a leaving group and that is eliminated by contact with an acid to form a hydrophilic group (e.g., a hydroxy group or a carboxy group). Among these, the resin (A) preferably further contains a structural unit (s) and / or a structural unit having an acid labile group in addition to the structural unit (I), more preferably at least one type of structural unit (s) and / or at least one type of structural unit (a1), and even more preferably at least one type of structural unit (s) and at least one type of structural unit (a1), or two types of structural units (a1). The content of the structural unit (I) is usually 1 to 90 mol %, preferably 3 to 80 mol %, more preferably 5 to 75 mol %, even more preferably 7 to 70 mol %, and still more preferably 7 to 65 mol %, based on all structural units in the resin (A). When the resin (A) contains structural units represented by formula (a4) and / or (a5) described below, the content of the structural unit (I) in the resin (A) of the present invention is preferably 5 to 75 mol %, more preferably 10 to 70 mol %, even more preferably 10 to 65 mol %, and particularly preferably 10 to 60 mol %, based on the total of all structural units in the resin (A) of the present invention.

[0034] <Structural unit (a1)> The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid labile group contained in the resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF2026001162000031.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.] TIFF2026001162000032.tif2279[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.]

[0035] 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. Ra1 , 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, octynyl, isooctynyl, 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. TIFF2026001162000033.tif9159R 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 groups include groups in which the above-mentioned alkyl groups and alicyclic hydrocarbon groups are combined (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, and norbornylethyl 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.), and aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.). and aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. 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-. TIFF2026001162000034.tif34157

[0036] 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. The alkyl group and the alicyclic hydrocarbon group are represented by R a1 , R a2 and R a3 Examples of the groups include the same as those listed in the 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 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. R a2’ and Ra3’ When they are bonded to each other to form a heterocycle together with the carbon atoms to which they are attached and X, -C(R a1’ )(R a2’ )-XR a3’ Examples of the ring include the following: * represents a binding site. TIFF2026001162000035.tif19123R a1’ and R a2’ At least one of these is preferably a hydrogen atom. na' is preferably 0.

[0037] 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. TIFF2026001162000036.tif112163

[0038] TIFF2026001162000037.tif65157

[0039] Specific examples of group (2) include the following groups: * represents a binding site. TIFF2026001162000038.tif68161

[0040] 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. 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.

[0041] Examples of structural units derived from a (meth)acrylic monomer having group (1) include a structural unit represented by formula (a1-0) (hereinafter, sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter, sometimes referred to as structural unit (a1-2)). Preferably, at least one structural unit selected from the group consisting of structural unit (a1-1) and structural unit (a1-2) is used. These may be used alone or in combination of two or more. TIFF2026001162000039.tif45149 [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 are each independently a hydrogen atom, a halogen atom or a halogen atom It represents an alkyl group having 1 to 6 carbon atoms which may have one or more atoms. R a02 , R a03 and R a04 are each independently an alkyl group having 1 to 8 carbon atoms, 18 alicyclic hydrocarbon groups, aromatic hydrocarbon groups having 6 to 18 carbon atoms, or combinations thereof. R a6 and R a7 are each independently 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 represents 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.

[0042] R a01 , R a4 and R a5 is preferably a hydrogen atom or a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or —O—(CH2) k01 -C It is OO- (wherein k01 is preferably an integer of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 and R a04 alkyl groups, alkenyl groups, alicyclic hydrocarbon groups, aromatic groups The aromatic hydrocarbon groups and groups formed by combining these groups include R a1 , R a2 and R a3 Listed in The same groups as those mentioned above can be mentioned. 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 The groups listed in Similar groups are mentioned. R a02 , R a03 , and R a04The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms. It is preferably a methyl group or an ethyl group, and 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 a7 The 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 number of carbon atoms in the alicyclic hydrocarbon group is preferably It is 5 to 12, and more preferably 5 to 10. R a02 , R a03 , R a04 , R a6 and R a7 The number of carbon atoms in the aromatic hydrocarbon group is preferably It is 6 to 12, and more preferably 6 to 10. 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 are each independently preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group. R a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon having 5 to 12 carbon atoms. group, and more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. R a6 and R a7 are each independently 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.

[0043] 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 a structural unit represented by any one of formulas (a1-0-1) to (a1-0-10), (a1-0-13), and (a1-0-14). Position is preferred. TIFF2026001162000040.tif95160

[0044] 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 a methyl group corresponding to the formula (a1-1-1) is replaced with a hydrogen atom is preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF2026001162000041.tif41170

[0045] The structural unit (a1-2) includes a structural unit represented by any one of formulas (a1-2-1) to (a1-2-12) and R a5 and structural units represented by formula (a1-2-2), formula (a1-2-5), formula (a1-2-6), and formula (a1-2-10) to formula (a1-2-12) are preferred. TIFF2026001162000042.tif64157

[0046] When the resin (A) contains the structural unit (a1-0), the content thereof is usually 5 to 60 mol %, preferably 5 to 50 mol %, and more preferably 10 to 40 mol %, based on all structural units in the resin (A). When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is usually 3 to 80 mol %, preferably 5 to 75 mol %, more preferably 7 to 70 mol %, even more preferably 7 to 65 mol %, and still more preferably 10 to 60 mol %, based on all structural units in the resin (A).

[0047] 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)"). TIFF2026001162000043.tif4768[In formula (a1-4), R a32 is a hydrogen atom, a halogen atom, or a C1-6 alkyl group optionally having a halogen atom represents an alkyl group represented by the formula: R a33 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a It represents an alkoxy group, 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 is combined represents the bonding site with the carbon atom. 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 combined with each other and These form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -CO- to which they are bonded, and the hydrocarbon The -CH2- contained in the alkyl group and the divalent hydrocarbon group is replaced by -O- or -S-. That's fine.]

[0048] 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 include: Examples 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, and is more preferably an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a33 The alkyl group in the formula (I) is a methyl group, an ethyl group, a propyl group, an isopropyl group, or the like. Examples of the butyl group include a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a33 The alkoxy group in the formula (I) is a methoxy group, an ethoxy group, a propoxy group, an isopropyl ... Examples of the alkoxy group include a propoxy 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 a33 The alkoxyalkyl group in the formula (I) is a methoxymethyl group or an ethoxyethyl group. Examples of the alkoxyalkyl group include 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 The alkoxyalkoxy group in the formula (I) is a methoxymethoxy group, a methoxyethoxy group, Examples of the alkoxyalkoxy group include an alkoxy 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 The alkylcarbonyl group in the formula (I) includes an acetyl group, a propionyl group, and a butyl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a33 The alkylcarbonyloxy group in the formula (I) is an acetyloxy group, a propionyloxy group, or The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a33 is a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, a An alkoxy group or an alkoxyalkoxy group having 2 to 8 carbon atoms is preferred, 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 is more preferred, and a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group is even more preferred.

[0049] *-X a31 -(A a32 -X a32 ) nc - includes *-O-, *-CO-O-, *-OC O-, *-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 *- Office Automation a32 -CO-O- is preferred.

[0050] A a32 The alkanediyl group in the formula (I) includes a methylene group, an ethylene group, a propane-1, 3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. A a32 is preferably a methylene group or an ethylene group.

[0051] A a30 is a single bond, *-CO-O- or *-CO-OA a32 -CO-O- is preferred, and a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is preferred. A single bond or *-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0052] la is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. R a34 , R a35 and R a36 The hydrocarbon group in the formula (I) may be an alkyl group or an alicyclic hydrocarbon group. , aromatic hydrocarbon groups, and groups combining these groups. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, 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): TIFF2026001162000044.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 alkyl group include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, Examples thereof include aromatic hydrocarbon groups having 6 to 18 carbon atoms and groups formed by combining these groups.

[0053] R a34 is preferably a hydrogen atom. R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a It is an alicyclic hydrocarbon group, more preferably a methyl group or an ethyl group. R a36 The hydrocarbon group is preferably an alkyl group having 1 to 18 carbon atoms, a R is an alicyclic hydrocarbon group, 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 aliphatic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. a36 in The alkyl group and the alicyclic hydrocarbon group are preferably unsubstituted. a36 in The aromatic hydrocarbon group is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms. -OC(R a34 )(R a35 )-OR a36 is an acid (e.g. p-toluenesulfonic acid), it is eliminated to form a hydroxy group. -OC(R a34 )(R a35 )-OR a36 is attached to the o- or p-position of the benzene ring It is preferable that the bond is at the p-position, and it is more preferable that the bond is at the p-position.

[0054] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferably, the structural units represented by formulas (a1-4-1) to (a1-4-18) and R in the structural unit (a1-4) are a32 and more preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-5), formula (a1-4-10), formula (a1-4-13), and formula (a1-4-14), respectively. TIFF2026001162000045.tif98157

[0055] When the resin (A) has the structural unit (a1-4), the content thereof is preferably 3 to 80 mol %, more preferably 5 to 75 mol %, even more preferably 7 to 70 mol %, even more preferably 7 to 65 mol %, and particularly preferably 10 to 60 mol %, based on the total of all structural units in the resin (A).

[0056] 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)"). TIFF2026001162000046.tif4253 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 is 1 to 4 represents an integer, and * 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.

[0057] Examples of the halogen atom include a fluorine atom and a chlorine atom, with a fluorine atom being preferred. Examples of the alkyl group having 1 to 6 carbon atoms and optionally having 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—.

[0058] 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. TIFF2026001162000047.tif31129

[0059] When the resin (A) has 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 the total structural units of the resin (A).

[0060] Further, examples of the structural unit (a1) include the following structural units. TIFF2026001162000048.tif31167

[0061] When the resin (A) contains the above structural unit, the content thereof is preferably 5 to 60 mol %, more preferably 5 to 50 mol %, and even more preferably 10 to 40 mol %, based on the total structural units of the resin (A).

[0062] <Structural unit(s)> The structural unit (s) is derived from a monomer (hereinafter sometimes referred to as "monomer (s)") that does not have an acid labile group. As the monomer from which the structural unit (s) is derived, a monomer that does not have an acid labile group known in the resist field can be used. The structural unit (s) preferably has a hydroxy group or a lactone ring. By using a resin having a structural unit that has a hydroxy group but no acid labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit that has a lactone ring but no acid labile group (hereinafter sometimes referred to as "structural unit (a3)") in the resist composition of the present invention, the resolution of the resist pattern and adhesion to the substrate can be improved.

[0063] <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) 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 below. 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.

[0064] In the structural unit (a2), the structural unit having a phenolic hydroxy group includes a structural unit represented by formula (a2-A) (hereinafter, sometimes referred to as "structural unit (a2-A)"). TIFF2026001162000049.tif4450[In formula (a2-A), R a50 is a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. represents an alkyl group. R a51 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a It represents an alkoxy group, 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.]

[0065] 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 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom is, for example, tri Examples include a fluoromethyl 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 a50 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and is more preferably an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a51 The alkyl group in the formula (I) is a methyl group, an ethyl group, a propyl group, an isopropyl group, or the like. Examples of the alkyl group include 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 The alkoxy group in the formula (I) is a methoxy group, an ethoxy group, a propoxy group, an isopropyl ... Examples of the alkoxy group include a propoxy 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 The alkoxyalkyl group in the formula (I) is a methoxymethyl group or an ethoxyethyl group. Examples of the alkoxyalkyl group include 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 The alkoxyalkoxy group in the formula (I) is a methoxymethoxy group, a methoxyethoxy group, Examples of the alkoxyalkoxy group include an alkoxy 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 The alkylcarbonyl group in the formula (I) includes an acetyl group, a propionyl group, and a butyl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a51The alkylcarbonyloxy group in the formula (I) is an acetyloxy group, a propionyloxy group, or The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a51 is a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, a An alkoxy group or an alkoxyalkoxy group having 2 to 8 carbon atoms is preferred, 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 is more preferred, and a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group is even more preferred.

[0066] *-X a51 -(A a52 -X a52 ) nb - includes *-O-, *-CO-O-, *-OC O-, *-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 *- Office Automation a52 -CO-O- is preferred.

[0067] A a52 The alkanediyl group in the formula (I) includes a methylene group, an ethylene group, a propane-1, 3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Aa52 is preferably a methylene group or an ethylene group.

[0068] A a50 is a single bond, *-CO-O- or *-CO-OA a52 -CO-O- is preferred, and a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is preferred. A single bond or *-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0069] mb is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. The hydroxy group is preferably bonded to the ortho- or para-position of the benzene ring, and more preferably to the para-position. It is more preferred to bind to

[0070] 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 (a2-2-16) and R in the structural unit (a2-A) in the structural units represented by formulae (a2-2-1) to (a2-2-16). a50 The structural unit (a2-A) includes a structural unit represented by formula (a2-2-1), a structural unit represented by formula (a2-2-3), a structural unit represented by formula (a2-2-6), a structural unit represented by formula (a2-2-8), and a structural unit represented by formula (a2-2-12) to formula (a2-2-14), as well as structural units in which R in the structural unit (a2-A) is replaced with a hydrogen atom. a50 It is preferable that the structural unit is a structural unit in which a methyl group corresponding to the following formula is substituted with a hydrogen atom: TIFF2026001162000050.tif58170

[0071] When the structural unit (a2-A) is contained in the resin (A), the content of the structural unit (a2-A) is preferably 5 to 80 mol %, more preferably 10 to 70 mol %, even more preferably 10 to 60 mol %, and still more preferably 10 to 50 mol %, based on all structural units. The structural unit (a2-A) can be incorporated into the resin (A) by, for example, 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 (A) by polymerizing the structural unit (a1-4) and then treating with an alkali such as tetramethylammonium hydroxide.

[0072] 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)"). TIFF2026001162000051.tif4158 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.

[0073] In equation (a2-1), L a3 is preferably -O-, -O-(CH2) f1 -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. Ra16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of 0 to 3, and more preferably 0 or 1.

[0074] 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. TIFF2026001162000052.tif54150

[0075] When the resin (A) contains the structural unit (a2-1), the content thereof is usually 1 to 45 mol %, preferably 1 to 40 mol %, more preferably 1 to 35 mol %, even more preferably 1 to 20 mol %, and still more preferably 1 to 10 mol %, based on all structural units of the resin (A).

[0076] <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)).

[0077] 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. TIFF2026001162000053.tif50153 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and La6 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-. L a8 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 and R a20 each independently represents a hydrogen atom or a methyl group. R a24 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. 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 or different.]

[0078] Ra21 , 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 a24 Examples of the halogen atom in the formula include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. 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 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.

[0079] 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, Examples include 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.

[0080] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or -O-(CH2) k3In -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 an integer of preferably 0 to 2, and more preferably 0 or 1.

[0081] 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)'. TIFF2026001162000054.tif3748 (in the formula, R a24 , L a7 has the same meaning as above.)

[0082] 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.

[0083] TIFF2026001162000055.tif115165

[0084] When the resin (A) contains the structural unit (a3), the total content thereof is usually 1 to 70 mol %, preferably 3 to 65 mol %, and more preferably 5 to 60 mol %, based on all structural units in the resin (A). Furthermore, 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 to 60 mol %, more preferably 3 to 50 mol %, and even more preferably 5 to 50 mol %, based on the total structural units of the resin (A).

[0085] <Structural unit (a4)> Examples of the structural unit (a4) include the following structural units. TIFF2026001162000056.tif3064[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 halogen atom, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO.] R 42Examples of the saturated hydrocarbon group represented by the formula (I) include a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these groups.

[0086] 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 a cyclopentyl group and a cyclohexyl group. cycloalkyl groups such as cycloheptyl and cyclooctyl; and polycyclic alicyclic saturated hydrocarbon groups such as decahydronaphthyl, adamantyl, and norbornyl, and the following groups (* indicates a bonding site): TIFF2026001162000057.tif10146 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.

[0087] Examples of the structural unit (a4) include a structural unit represented by formula (a4-0), a structural unit represented by formula (a4-1), and a structural unit represented by formula (a4-4). TIFF2026001162000058.tif4147[In formula (a4-0), R 54 represents a hydrogen atom or a methyl group. L 4a represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 3a is a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluoroalkanediyl group having 3 to 12 carbon atoms. represents a fluorocycloalkanediyl group. R 64 represents a hydrogen atom or a fluorine atom.

[0088] L 4a The alkanediyl group in the formula (I) includes a methylene group, an ethylene group, a propane-1, and branched alkanediyl groups such as ethane-1,1-diyl, propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,3-diyl, and 2-methylpropane-1,2-diyl.

[0089] L 3a The perfluoroalkanediyl group in Fluoroethylene group, perfluoroethylfluoromethylene group, perfluoropropane-1,3-diyl group, perfluoropropane-1,2-diyl group, perfluoropropane-2,2-diyl group, perfluorobutane-1,4-diyl group, perfluorobutane-2,2-diyl group, perfluorobutane-1,2-diyl group, perfluoropentane-1,5-diyl group, perfluoropentane-2,2-diyl group, perfluoropentane-3,3-diyl group, perfluorohexane 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 The perfluorocycloalkanediyl group in Examples thereof include a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, and a perfluoroadamantanediyl group.

[0090] L 4a is preferably a single bond, a methylene group or an ethylene group, more preferably a single bond, bond, a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, more preferably or a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0091] 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. 54 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026001162000059.tif96166

[0092] TIFF2026001162000060.tif4867[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, The -CH2- contained in the 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 the formula (ag 1), where A a41 and R a42 At least one of the groups has a halogen atom (preferably a fluorine atom) as a substituent. TIFF2026001162000061.tif1488 [In formula (a-g1), s represents 0 or 1. A a42 and A a44 are each independently a divalent group having 1 to 5 carbon atoms which may have a substituent. Represents a saturated hydrocarbon group. A a43 represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. Represents. X a41 and X a42each independently represents -O-, -CO-, -CO-O- or -O-CO-. However, A a42 , A a43 , A a44 , X a41 and X a42 The total number of carbon atoms is 7 or less. * indicates the binding site, and the * on the right is -O-CO-R a42 ]

[0093] R a42 The saturated hydrocarbon group in the formula (I) includes a chain hydrocarbon group and a monocyclic or polycyclic saturated alicyclic group. and groups formed by combining these.

[0094] Examples of the chain 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 saturated alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* indicates a bonding site): TIFF2026001162000062.tif10159 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 saturated alicyclic hydrocarbon groups, such as -alkanediyl group-saturated alicyclic hydrocarbon group, -saturated alicyclic hydrocarbon group-alkyl group, and -alkanediyl group-saturated alicyclic hydrocarbon group-alkyl group.

[0095] R a42 The substituents of the compound (a-g1) are a halogen atom and a group represented by formula (a-g3): Examples of halogen atoms include at least one selected from the group consisting of: Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, and a fluorine atom is preferred. TIFF2026001162000063.tif855[In formula (a-g3), X a43 represents an oxygen atom, a carbonyl group, *-O-CO- or *-CO-O-. A a45 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. * denotes 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 a saturated hydrocarbon group having 1 to 17 carbon atoms and at least one halogen atom.

[0096] A a45 The saturated hydrocarbon group in the formula (I) is a methyl group, an ethyl group, a propyl group, or a butyl group. alkyl groups such as pentyl, hexyl, heptyl, octyl, decyl, dodecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups; monocyclic alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups; and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl, adamantyl, norbornyl, and the following groups (* indicates a bonding site): TIFF2026001162000064.tif10159 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.

[0097] R a42is preferably a saturated hydrocarbon group which may have a halogen atom, An alkyl group having the formula and / or a saturated hydrocarbon group having a group represented by formula (a-g3) is more preferred. R a42 When is a saturated hydrocarbon group having a halogen atom, it is preferably a saturated hydrocarbon group having a fluorine atom. The perfluoroalkyl group is a saturated hydrocarbon group having 1 to 6 carbon atoms, 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 a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group, a perfluoroheptyl group, and a perfluorooctyl group. Examples of perfluorocycloalkyl groups include a perfluorocyclohexyl group. R a42 is a saturated hydrocarbon group having a group represented by formula (a-g3), g3) and the number of carbon atoms contained in the group represented by R a42 The total number of carbon atoms is preferably 15 or less. The number of the groups represented by formula (a-g3) is preferably 1, and more preferably 12 or less. When the group represented by formula (a-g3) is contained as a substituent, the number thereof is preferably 1.

[0098] R a42 is a saturated hydrocarbon group having a group represented by formula (a-g3), R a42 is more preferably a group represented by formula (a-g2). TIFF2026001162000065.tif872[In formula (a-g2), A a46 represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. represent. X a44 represents **-O-CO- or **-CO-O- (** represents A a46 represents the binding site with ). A a47represents a saturated 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 of At least one of them has at least one halogen atom. * indicates the bonding site with the carbonyl group.]

[0099] A a46 The saturated hydrocarbon group preferably has 1 to 6 carbon atoms, and more preferably 1 to 3 carbon atoms. A a47 The saturated 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.

[0100] A preferred structure of the group represented by formula (a-g2) is the following structure (* indicates the bonding site with the carbonyl group): TIFF2026001162000066.tif14160

[0101] A a41 The alkanediyl group in the formula (I) includes a methylene group, an ethylene group, a propane-1, linear alkanediyl groups such as 1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, and hexane-1,6-diyl group; and branched alkanediyl groups such as propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. A a41 The substituents in the alkanediyl group represented by the formula (I) include a hydroxy group and an alkanediyl group having 1 to 10 carbon atoms. Examples of the alkoxy group include alkoxy groups of formula 6. A a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably It is preferably an alkanediyl group having 2 to 4 carbon atoms, and more preferably an ethylene group.

[0102] A in the group represented by formula (a-g1) a42 , A a43 and A a44 represents the divalent saturated hydrocarbon Examples of the alkyl group include a linear or branched alkanediyl group, a monocyclic divalent alicyclic saturated hydrocarbon group, and a divalent saturated hydrocarbon group formed by combining an alkanediyl group with a divalent alicyclic saturated hydrocarbon group, etc. 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 The substituent of the divalent saturated hydrocarbon group represented by is a hydroxy group. and alkoxy groups having 1 to 6 carbon atoms. Preferably, s is 0.

[0103] In the group represented by formula (a-g1), X a42 is -O-, -CO-, -CO-O- or Examples of the -O-CO- group include the following groups: In the following examples, * and ** each represent a bonding site, and ** represents -O-CO-R a42 This is the binding site for TIFF2026001162000067.tif46140

[0104] 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 A methyl group corresponding to Examples of structural units that have been replaced include:

[0105] TIFF2026001162000068.tif101147

[0106] TIFF2026001162000069.tif132150

[0107] Examples of the structural unit represented by formula (a4-1) include a structural unit represented by formula (a4-2) and a structural unit represented by formula (a4-3). TIFF2026001162000070.tif4256[In formula (a4-2), R f5 represents 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.]

[0108] L 44 The alkanediyl group having 1 to 6 carbon atoms is A a41 The same groups as those exemplified in can be. R f6 The saturated hydrocarbon group of R 42 Examples of the groups include the same groups as those exemplified in L 44 The alkanediyl group in the formula (I) is preferably an alkanediyl group having 2 to 4 carbon atoms, more preferably an ethylene group.

[0109] 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 in which the corresponding methyl group is replaced by a hydrogen atom is also represented by formula (a4-2). It is one of the structural units.

[0110] TIFF2026001162000071.tif5266[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 have a fluorine atom. vinegar. X f12 represents *-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.

[0111] L 5 The alkanediyl group in a41 Examples of the alkanediyl group include the same groups as those exemplified as the alkanediyl group.

[0112] A f13 The divalent saturated hydrocarbon group optionally having a fluorine atom in More preferably, it is a divalent chain saturated hydrocarbon group which may have a fluorine atom and a divalent alicyclic saturated hydrocarbon group which may have 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.

[0113] A f14 The saturated hydrocarbon group and the saturated hydrocarbon group which may have a fluorine atom are R a42 Among 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 fluorinated alkyl groups such as 2,3,3,4,4,5,5,5-nonafluoropentyl group, pentyl group, hexyl group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group and perfluorooctyl group, cyclopropylmethyl group, cyclopropyl group, cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group, norbornylmethyl group, perfluoroadamantyl group and perfluoroadamantylmethyl group are preferred.

[0114] In formula (a4-3), L 5 is preferably an ethylene group. A f13 The divalent saturated hydrocarbon group is a divalent chain saturated hydrocarbon group having 1 to 6 carbon atoms and a carbon A group containing a divalent alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms is preferred, and a divalent chain saturated hydrocarbon group having 2 to 3 carbon atoms is more preferred. A f14 The saturated hydrocarbon group is a chain saturated hydrocarbon group having 3 to 12 carbon atoms and a A group containing an alicyclic saturated hydrocarbon group of the formula (I) is preferred, and a group containing a chain saturated hydrocarbon group having 3 to 10 carbon atoms and an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms is more preferred. f14 teeth Preferably, it is a group containing an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably, it is a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, or an adamantyl group.

[0115] 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 in which the corresponding methyl group is replaced by a hydrogen atom is also represented by formula (a4-3). It is one of the structural units that can be mentioned.

[0116] The structural unit (a4) also includes a structural unit represented by formula (a4-4). TIFF2026001162000072.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.]

[0117] R f22 The saturated hydrocarbon group of R a42 R f22 is an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, or a carbon atom having a fluorine atom Alicyclic saturated hydrocarbon groups having 1 to 10 prime numbers are preferred, alkyl groups having 1 to 10 carbon atoms and containing a fluorine atom are more preferred, and alkyl groups having 1 to 6 carbon atoms and containing a fluorine atom are even more preferred.

[0118] In formula (a4-4), A f21 As -(CH2) j1 - is preferred, and ethylene A group or a methylene group is more preferred, and a methylene group is even more preferred.

[0119] 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 methyl group corresponding to Examples of structural units include those in which hydrogen atoms are replaced. TIFF2026001162000073.tif86160

[0120] When the resin (A) has the structural unit (a4), the content thereof is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and even more preferably 3 to 10 mol %, based on all structural units in the resin (A).

[0121] <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). TIFF2026001162000074.tif3553[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 55represents 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-.]

[0122] 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 a methyl group, an ethyl group, a propyl group, an isopropyl group, and an isopropyl group. Examples of alkyl groups include propyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl groups. 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.

[0123] 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.

[0124] L 55Examples 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. TIFF2026001162000075.tif18164 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 x2 represents 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 x1represents 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.

[0125] 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 It is 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.

[0126] Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF2026001162000076.tif53136

[0127] Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF2026001162000077.tif23130

[0128] Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF2026001162000078.tif15144

[0129] Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF2026001162000079.tif26114

[0130] L 55 is preferably a single bond or a group represented by formula (L1-1).

[0131] 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. TIFF2026001162000080.tif74152

[0132] When the resin (A) has the structural unit (a5), the content thereof is preferably 1 to 30 mol %, more preferably 2 to 20 mol %, and even more preferably 3 to 15 mol %, based on all structural units in the resin (A).

[0133] <Structural unit (II)> The resin (A) 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.

[0134] The structural unit having a sulfonate group or carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (II-2-A'). TIFF2026001162000082.tif3189[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.

[0135] 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: a8Examples 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 x1 Examples 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 perfluoroalkyl group having 1 to 6 carbon atoms which may be substituted 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 Examples of the alkyl group include a perfluoropentyl group, a perfluorohexyl group, and the like.

[0136] 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 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; and 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. divalent monocyclic 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 divalent polycyclic 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.

[0137] 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 TIFF2026001162000083.tif145161

[0138] X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0139] ZA + Examples of the organic cation represented by the formula include organic onium cations, organic sulfonium cations, and the like. Examples of the cation include thione, organic iodonium cation, organic ammonium cation, benzothiazolium cation, and organic phosphonium cation. Among these, organic sulfonium cation and organic iodonium cation are preferred, and arylsulfonium cation is more preferred. Specific examples include cations represented by any of formulas (b2-1) to (b2-4) described below.

[0140] The structural unit represented by formula (II-2-A') is preferably a structural unit represented by formula (II-2-A). JPEG2026001162000084.jpg37108 [In formula (II-2-A), R III3 , X III3 and ZA + has the same meaning as above. z 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 z is 2 or more, a plurality of R III2 and R III4 may be the same 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.]

[0141] R III2 , R III4 , Q a and Q b As the perfluoroalkyl group having 1 to 6 carbon atoms represented by the formula (I), the following Q b1 Examples include the same perfluoroalkyl groups having 1 to 6 carbon atoms as those represented by the following formula:

[0142] The structural unit represented by formula (II-2-A) is preferably a structural unit represented by formula (II-2-A-1). TIFF2026001162000085.tif5575 [In formula (II-2-A-1), R III2, R III3 , R III4 , Q a , Q b , z and ZA + has the same meaning as above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, and the saturated hydrocarbon group -CH2- may be replaced by -O-, -S- or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted by a halogen atom or a hydroxy group.

[0143] 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:

[0144] The structural unit represented by formula (II-2-A-1) is preferably a structural unit represented by formula (II-2-A-2). The structural unit is preferably TIFF2026001162000086.tif5187 [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.]

[0145] Examples of the structural unit represented by formula (II-2-A') include the following structural units, R III3Examples of the structural units include those 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. TIFF2026001162000087.tif86163

[0146] 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). TIFF2026001162000088.tif3380[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 in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined, aralkyl groups such as a benzyl group, aromatic hydrocarbon groups having an alkyl group (e.g., p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (e.g., p-cyclohexylphenyl group, p-adamantylphenyl group), and aryl-cycloalkyl groups such as a phenylcyclohexyl group. R 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:

[0147] The structural unit containing a cation in formula (II-1-1) includes the structural unit represented by the following formula: R II4 The group corresponding to the methyl group in the formula (I) is a hydrogen atom, a halogen atom (e.g., a fluorine atom), or is substituted with an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group, etc.), and the like. TIFF2026001162000089.tif88136

[0148] 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 examples of the sulfonate anion include the same anions as those represented by the formula (B1) described below.

[0149] A - Examples of the sulfonylimide anion represented by the formula (I) include the following. TIFF2026001162000090.tif37136

[0150] Examples of sulfonylmethide anions include the following: TIFF2026001162000091.tif29123

[0151] Examples of carboxylate anions include the following: TIFF2026001162000092.tif51152

[0152] Examples of the structural unit represented by formula (II-1-1) include structural units represented by the following formulas. TIFF2026001162000093.tif88149

[0153] When the structural unit (II) is contained in the resin (A), 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 (A).

[0154] The resin (A) may have structural units other than the above-mentioned structural units, and examples of such structural units include structural units well known in the art.

[0155] Resin (A) is preferably a resin consisting of structural units (I) and (a1), a resin consisting of structural units (I) and (s), a resin consisting of structural units (I), (a1), and (s), a resin consisting of structural units (I), (a1), (s), and (a4) and / or (a5), a resin consisting only of structural units (I), or a resin consisting only of structural units (I) and (a4), and more preferably a resin consisting of structural units (I) and (a1), a resin consisting of structural units (I) and (s), or a resin consisting of structural units (I), (a1), and (s).

[0156] The structural unit (a1) is preferably a structural unit (a1-0), a structural unit (a1-0X ... The structural unit is at least one selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2) (preferably a structural unit having a cyclohexyl group or a cyclopentyl group), and more preferably at least two selected from the group consisting of the structural unit (a1-0), the structural unit (a1-0X), the structural unit (a1-1) and the structural unit (a1-2) (preferably a structural unit having a cyclohexyl group or a cyclopentyl group). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably the structural unit (a2-1) or the structural unit (a2-A). The structural unit (a3) ​​is preferably at least one selected from the group consisting of the structural unit represented by formula (a3-1), the structural unit represented by formula (a3-2), and the structural unit represented by formula (a3-4).

[0157] The structural units constituting the resin (A) may be used singly or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization) using monomers that lead to these structural units. The content of each structural unit in the resin (A) can be adjusted by the amount of monomer used in the polymerization. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, 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). In this specification, the weight average molecular weight is a value determined by gel permeation chromatography, which can be measured under the analytical conditions described in the Examples.

[0158] [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 resin (A) that does not contain a structural unit derived from compound (I). 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)").

[0159] <Resins other than Resin (A)> The resist composition of the present invention may contain a resin other than resin (A). A resin other than resin (A) is a resin that does not contain structural unit (I). Examples of such a resin include a resin that has a structural unit having an acid labile group but does not contain structural unit (I) (hereinafter, may be referred to as "resin (AY)"), a resin consisting only of structural unit (a4), and a resin consisting of structural unit (a4) and structural unit (a5) (hereinafter, a resin consisting only of structural unit (a4) and a resin consisting of structural unit (a4) and structural unit (a5) may be collectively referred to as resin (X)). In the resin (X), the content of the structural unit (a4) is preferably 30 mol % or more, more preferably 40 mol % or more, and even more preferably 45 mol % or more, based on the total of all structural units in the resin (X). The structural units constituting the resin (X) may be used singly or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization) using monomers that derive 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 weights of resin (AY) and resin (X) are each independently preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less). The means for measuring the weight average molecular weights of resin (AY) and resin (X) are the same as those for resin (A). When the resist composition of the present invention contains resin (AY), the content thereof is typically from 1 to 2500 parts by mass (more preferably from 10 to 1000 parts by mass) per 100 parts by mass of 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).

[0160] The content of resin (A) in the resist composition is preferably 80 to 99 mass% based on the solid content of the resist composition, and more preferably 90 to 99 mass%. Furthermore, when a resin other than resin (A) is contained, the total content of resin (A) and the resin other than resin (A) based on the solid content of the resist composition is preferably 80 to 99 mass% based on the solid content of the resist composition, and more preferably 90 to 99 mass%. 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.

[0161] <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.

[0162] 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.

[0163] The acid generator (B) is preferably a fluorine-containing acid generator, and more preferably a salt represented by formula (B1) (hereinafter sometimes referred to as "acid generator (B1)"). TIFF2026001162000094.tif2961[In formula (B1), Q b1 and Q b2 each independently represents a fluorine atom 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 is not limited to -O-, - It may be replaced by S(O)2- or -CO-. Z1 + represents an organic cation.

[0164] Q b1 and Q b2 Examples of the perfluoroalkyl group represented by 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, and a perfluorohexyl group. Q b1 and Q b2 and are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably both are fluorine atoms.

[0165] 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.

[0166] 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.

[0167] TIFF2026001162000095.tif26118[In formula (b1-1), L b2 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 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. * and ** represent binding sites, and * represents the binding site with Y.]

[0168] 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. L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4is 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. 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-.

[0169] 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). TIFF2026001162000096.tif48120[In formula (b1-4), L b8 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, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b9 and L b10The 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, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. 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, The -CH2- contained in the hydrogen hydride 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, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b13 ~L b15 The total number of carbon atoms is 19 or less. In formula (b1-8), L b16 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the divalent saturated hydrocarbon group The contained -CH2- may be replaced by -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, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b16 ~L b18 The total number of carbon atoms is 19 or less. * and ** represent binding sites, and * represents the binding site with Y.] 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 Preferably, it is 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 Preferably, it is 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 b18 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and more preferably Preferably, it is a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0170] Examples of the group represented by formula (b1-3) include groups represented by formulas (b1-9) to (b1-11). TIFF2026001162000097.tif22140[In formula (b1-9), L b19represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, A hydrogen atom contained in the 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, The hydrogen atom contained in the group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. The —CH2— contained in the alkylcarbonyloxy group is replaced with —O—. Alternatively, the hydrogen atom contained in the alkylcarbonyloxy group may be substituted with —CO—, and the 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, A hydrogen atom contained in the 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, The hydrogen atom contained in the group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. The —CH2— contained in the alkylcarbonyloxy group is replaced with —O—. Alternatively, the hydrogen atom contained in the alkylcarbonyloxy group may be substituted with —CO—, and the hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b21 , L b22 and L b23 The total number of carbon atoms is 21 or less. Binding Site Binding Site In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, A hydrogen atom contained in the 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, The hydrogen atom contained in the group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. The —CH2— contained in the alkylcarbonyloxy group is replaced with —O—. Alternatively, the hydrogen atom contained in the alkylcarbonyloxy group may be substituted with —CO—, and the 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. * and ** represent binding sites, and * represents the binding site with Y.]

[0171] 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.

[0172] Examples of the group represented by formula (b1-4) include the following. TIFF2026001162000098.tif17150 (* and ** represent binding sites, * represents the binding site with Y.)

[0173] Examples of the group represented by formula (b1-5) include the following. TIFF2026001162000099.tif72149 (* and ** represent binding sites, * represents the binding site with Y.)

[0174] Examples of the group represented by formula (b1-6) include the following. TIFF2026001162000100.tif29150 (* and ** represent binding sites, * represents the binding site with Y.)

[0175] Examples of the group represented by formula (b1-7) include the following. TIFF2026001162000101.tif64151 (* and ** represent binding sites, * represents the binding site with Y.)

[0176] Examples of the group represented by formula (b1-8) include the following. TIFF2026001162000102.tif23150 (* and ** represent binding sites, * represents the binding site with Y.)

[0177] Examples of the group represented by formula (b1-2) include the following. TIFF2026001162000103.tif31161 (* and ** represent binding sites, * represents the binding site with Y.)

[0178] Examples of the group represented by formula (b1-9) include the following. TIFF2026001162000104.tif44137 (* and ** represent binding sites, * represents the binding site with Y.)

[0179] Examples of the group represented by formula (b1-10) include the following. TIFF2026001162000105.tif89157 (* and ** represent binding sites, * represents the binding site with Y.)

[0180] Examples of the group represented by formula (b1-11) include the following. TIFF2026001162000106.tif82158 (* and ** represent binding sites, * represents the binding site with Y.)

[0181] Examples of the alicyclic hydrocarbon group represented by Y include groups represented by formulae (Y1) to (Y11) and (Y36) to (Y38). When -CH2- contained in the alicyclic hydrocarbon group represented by Y is replaced by -O-, -S(O)2- 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). * represents L b1 represents the binding site with The alicyclic hydrocarbon group represented by TIFF2026001162000107.tif83170Y is preferably a group represented by any one of formulas (Y1) to (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), and formulas (Y39) to (Y43), and more preferably a group represented by formula (Y11), formula (Y15), formula (Y16), formula (Y20), formula (Y41), formula (Y42), formula (Y43), or formula (Y44). Preferred are groups represented by formula (Y11), formula (Y15), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42), or formula (Y43), and more preferred are groups represented by formula (Y11), formula (Y15), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42), or formula (Y43). When the alicyclic hydrocarbon group represented by Y is a spiro ring containing an oxygen atom such as those of formulae (Y28) to (Y35), (Y39) to (Y40), (Y42) or (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.

[0182] 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 group combining these, wherein -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, or the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. ja represents an integer of 0 to 4. 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 group combining these, wherein -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, or the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. ja represents an integer of 0 to 4.

[0183] 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-adamantylphenyl and p-cyclohexylphenyl). 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 alkyl groups substituted with hydroxy groups include hydroxymethyl groups, hydroxy Examples include hydroxyalkyl groups such as an ethyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkyl group in which -CH2- is replaced by -O-, -S(O)2-, -CO-, or the like include an alkoxy 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 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- contained in the alicyclic hydrocarbon group is replaced by -O-, -S(O)2-, -CO- or the like include groups represented by formulae (Y12) to (Y35) and formulae (Y39) to (Y43).

[0184] Examples of Y include the following: TIFF2026001162000108.tif102165

[0185] TIFF2026001162000109.tif63161

[0186] 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, wherein -CH2- constituting the alicyclic hydrocarbon group or the adamantyl group may be replaced by -CO-, -S(O)2- or -CO-. Specifically, Y is preferably an adamantyl group, a hydroxyadamantyl group, an oxoadamantyl group or a group represented by formula (Y42) or formula (Y100) to formula (Y114).

[0187] The anion in the salt represented by formula (B1) is preferably an anion represented by formula (B1-A-1) to formula (B1-A-59) [hereinafter, it may be referred to as "anion (B1-A-1)" or the like depending on the formula number.], and more preferably an anion represented by 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), formula (B1-A-47) to formula (B1-A-5 9) is more preferred.

[0188] TIFF2026001162000110.tif143153

[0189] TIFF2026001162000111.tif62163

[0190] TIFF2026001162000112.tif94145

[0191] TIFF2026001162000113.tif115157

[0192] TIFF2026001162000114.tif49126

[0193] TIFF2026001162000115.tif183164

[0194] where 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. L is 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, and 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.

[0195] Preferable anions in the salt represented by formula (B1) include anions represented by formulas (B1a-1) to (B1a-38). TIFF2026001162000116.tif125153

[0196] TIFF2026001162000117.tif92138

[0197] TIFF2026001162000118.tif167155

[0198] Among these, anions represented by any of formulas (B1a-1) to (B1a-3), (B1a-7) to (B1a-16), (B1a-18), (B1a-19), and (B1a-22) to (B1a-38) are preferred.

[0199] 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). TIFF2026001162000119.tif47166In equations (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 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. good. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon 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 are each independently a chain hydrocarbon group having 1 to 36 carbon atoms or a chain hydrocarbon group having 3 to 4 carbon atoms, Represents 36 alicyclic hydrocarbon groups. R b9 and R b10 are bonded to each other and form a ring with the sulfur atom to which they are attached -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. Good too. R b11 is a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, It represents a hydrogen group 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 It represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 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 is replaced by -O-, -S- or -CO-. It is also possible. R b13 ~R b18 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. 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, r2 When 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.

[0200] 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: TIFF2026001162000120.tif10158 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably has 4 to 12 carbon atoms.

[0201] 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.

[0202] Examples of aromatic hydrocarbon groups include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, etc. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples thereof include aromatic hydrocarbon groups having a chain hydrocarbon group (such as a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.) and aromatic hydrocarbon groups having an alicyclic hydrocarbon group (such as a p-cyclohexylphenyl group, a p-adamantylphenyl group, etc.). When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of 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.

[0203] 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 halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. do. 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.

[0204] R b4 and R b5 and 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. TIFF2026001162000121.tif23143

[0205] R b9 and R b10 The ring formed by combining and can be monocyclic, polycyclic, aromatic, or non-aromatic. The ring may be either saturated or unsaturated. Examples of this ring include a 3- to 12-membered ring, and preferably a 3- to 7-membered ring. Examples 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 b12The 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.

[0206] Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferred. Examples of the cation (b2-1) include the following cations. TIFF2026001162000122.tif80158

[0207] TIFF2026001162000123.tif113165

[0208] Examples of the cation (b2-2) include the following cations. TIFF2026001162000124.tif17151

[0209] Examples of the cation (b2-3) include the following cations. TIFF2026001162000125.tif26140

[0210] Examples of the cation (b2-4) include the following cations. TIFF2026001162000126.tif127165

[0211] 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-3), (B1a-7) to (B1a-16), (B1a-18), (B1a-19), and (B1a-22) to (B1a-34) with a cation (b2-1), a cation (b2-3), or a cation (b2-4).

[0212] Preferred examples of the acid generator (B) include those represented by formulas (B1-1) to (B1-56). 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 (B1-56) are particularly preferred. TIFF2026001162000127.tif119149

[0213] TIFF2026001162000128.tif77147

[0214] TIFF2026001162000129.tif147147

[0215] TIFF2026001162000130.tif64163

[0216] TIFF2026001162000131.tif111148

[0217] TIFF2026001162000132.tif91159

[0218] In the resist composition of the present invention, the content of the acid generator is preferably 1 part by mass or more and 45 parts by mass or less, more preferably 1 part by mass or more and 40 parts by mass or less, even more preferably 3 parts by mass or more and 40 parts by mass or less, and even more preferably 10 parts by mass or more and 40 parts by mass or less, relative to 100 parts by mass of the resin (A) described below.

[0219] <Solvent (E)> The content of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less. The content of the solvent (E) is preferably from 92% by mass to 99% by mass, and more preferably from 94% by mass to 99% by mass. The content of the solvent (E) can be measured by a 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.

[0220] <Quencher (C)> The quencher (C) can be a basic nitrogen-containing organic compound or a salt that generates an acid that is weaker in acidity than the acid generated from the acid generator (B). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15 mass%, more preferably about 0.1 to 10 mass%, even more preferably about 0.1 to 5 mass%, and even more preferably about 0.1 to 3 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. 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, tributylamine, Amine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine amine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane Examples of the amines include 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. Preferred are aromatic amines such as diisopropylaniline, and more preferred is 2,6-diisopropylaniline. 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, etc. and the like.

[0221] The acidity of a salt that generates an acid weaker in acidity than the acid generated from the acid generator (B) is indicated by the acid dissociation constant (pKa). A salt that generates an acid weaker in acidity than the acid generated from the acid generator (B) is a salt having an acid dissociation constant of the acid generated from the salt usually of -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. Examples of the salt that generates an acid weaker in acidity than the acid generated from the acid generator (B) include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. Preferably, the salt that generates an acid weaker in acidity than the acid generated from the acid generator (B) is a salt that generates a carboxylic acid weaker in acidity than the acid generated from the acid generator (B) (a salt having a carboxylic acid anion), and more preferably, it is the weak acid inner salt (D). TIFF2026001162000133.tif89165

[0222] Examples of the weak acid inner salt (D) include the following salts. TIFF2026001162000134.tif72165

[0223] <Other Components> The resist composition of the present invention may contain, if necessary, components other than the above-described components (hereinafter referred to as "other components"). The other component (F) may also contain other additives. There are no particular limitations on the other component (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc., can be used.

[0224] <Preparation of Resist Composition> The resist composition of the present invention can be prepared by mixing resin (A), acid generator (B), and, if necessary, resins other than resin (A), solvent (E), 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, etc., the solubility of the resin, etc. in the solvent (E), etc. The mixing time can be selected from 0.5 to 24 hours, depending on the mixing temperature. The mixing means 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.

[0225] <Method for producing a resist pattern> The method for producing a resist pattern of the present invention comprises: (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. 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 usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. The exposure light source is an ultraviolet laser such as a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), or an F2 excimer laser (wavelength 157 nm). Various types of exposure light sources can be used, including those that emit laser light, those that convert the wavelength of laser light from a solid-state laser light source (such as a YAG or semiconductor laser) to emit harmonic laser light in the far ultraviolet or vacuum ultraviolet region, 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 usually 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. 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. Any solution may be used. For example, an aqueous solution of tetramethylammonium hydroxide or (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline) may be used. The alkaline developer may 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.

[0226] <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]

[0227] 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 analytical conditions: Column: TSKgel Multipore HXL-M x 3 + guard column (Tosoh Corporation) 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."

[0228] Example 1: Synthesis of compound represented by formula (I-13) 20 parts of the compound represented by formula (I-13-a), 2.28 parts of the compound represented by formula (I-13-c), 100 parts of ethyl acetate, and 15 parts of tetrahydrofuran were mixed and stirred at 23 ° C. for 30 minutes. 6.55 parts of the compound represented by formula (I-13-b) were added to the resulting mixed solution and stirred at 23 ° C. for 18 hours. 20 parts of n-heptane and 70 parts of ion-exchanged water were added to the resulting reaction mass and stirred at 23 ° C. for 30 minutes, followed by separation to extract the organic layer. 60 parts of ion-exchanged water was added to the recovered organic layer and stirred at 23 ° C. for 30 minutes, followed by separation to extract the organic layer. This water washing procedure was repeated four times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=1 / 1) to obtain 7.48 parts of the compound represented by formula (I-13-d). TIFF2026001162000136.tif68140 10.53 parts of the compound represented by formula (I-13-e), 7.10 parts of the compound represented by formula (I-13-f), and 30 parts of acetonitrile were mixed and stirred at 23 ° C for 30 minutes, followed by stirring at 60 ° C for 1 hour. 7.26 parts of the compound represented by formula (I-13-d) were added to the resulting mixture and stirred at 60 ° C for 1 hour. The resulting reaction mass was cooled to 23 ° C, and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and stirred at 23 ° C for 30 minutes, after which the organic layer was separated and isolated. This water washing procedure was repeated four times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=5 / 1) to obtain 10.88 parts of the compound represented by formula (I-13). MASS (mass spectrometry):429.2[M+H] +

[0229] Example 2: Synthesis of compound represented by formula (I-1) TIFF2026001162000137.tif62109 4.27 parts of the compound represented by formula (I-13), 1.89 parts of p-toluenesulfonic acid, and 30 parts of acetonitrile were mixed and stirred at 23 ° C for 30 minutes, followed by stirring at 60 ° C for 10 hours. The resulting mixture was cooled to 23 ° C, and 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added. The mixture was stirred at 23 ° C for 30 minutes, and then separated to separate the organic layer. 20 parts of ion-exchanged water was added to the resulting organic layer, and the mixture was stirred at 23 ° C for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The resulting organic layer was concentrated to obtain 2.49 parts of the compound represented by formula (I-1). MASS (mass spectrometry):357.2[M+H] +

[0230] Example 3: Synthesis of compound represented by formula (I-14) 5.00 parts of the compound represented by formula (I-14-a), 0.008 parts of the compound represented by formula (I-13-c), and 50 parts of toluene were mixed and stirred at 23 ° C. for 30 minutes, and then heated to 100 ° C. 6.19 parts of the compound represented by formula (I-14-b) were added dropwise to the resulting mixture at 100 ° C., stirred at 110 ° C. for 2 hours, and then cooled to 23 ° C. 25 parts of ethyl acetate and 30 parts of ion-exchanged water were added to the resulting mixture, and the mixture was stirred at 23 ° C. for 30 minutes, followed by separation to separate the organic layer. 30 parts of ion-exchanged water was added to the recovered organic layer, and the mixture was stirred at 23 ° C. for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The resulting organic layer was concentrated to obtain 5.85 parts of the compound represented by formula (I-14-d). 7.49 parts of the compound represented by formula (I-13-e), 5.06 parts of the compound represented by formula (I-13-f), and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 1 hour. 5.79 parts of the compound represented by formula (I-14-d) were added to the resulting mixture and stirred at 60°C for 1 hour. The resulting reaction mass was cooled to 23°C, and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. 50 parts of ion-exchanged water was added to the recovered organic layer and stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=10 / 1) to obtain 7.93 parts of the compound represented by formula (I-14). MASS (mass spectrometry):413.2[M+H] +

[0231] Example 4: Synthesis of compound represented by formula (I-2) 4.11 parts of the compound represented by formula (I-14), 1.89 parts of p-toluenesulfonic acid, and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 10 hours. The resulting mixture was cooled to 23°C, and 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added. The mixture was stirred at 23°C for 30 minutes, and then separated to separate the organic layer. 20 parts of ion-exchanged water was added to the resulting organic layer, and the mixture was stirred at 23°C for 30 minutes. The organic layer was then separated to separate the organic layer. This water washing procedure was repeated three times. The resulting organic layer was concentrated to obtain 2.69 parts of the compound represented by formula (I-2). MASS (mass spectrometry):373.2[M+H] +

[0232] Example 5: Synthesis of compound represented by formula (I-32) 7.54 parts of the compound represented by formula (I-32-e), 5.06 parts of the compound represented by formula (I-13-f), and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 1 hour. 5.79 parts of the compound represented by formula (I-14-d) were added to the resulting mixture and stirred at 60°C for 1 hour. The resulting reaction mass was cooled to 23°C, and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. 50 parts of ion-exchanged water was added to the recovered organic layer and stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=10 / 1) to obtain 8.02 parts of the compound represented by formula (I-32). MASS (mass spectrometry):415.1[M+H] +

[0233] Example 6: Synthesis of compound represented by formula (I-30) 4.13 parts of the compound represented by formula (I-32), 1.89 parts of p-toluenesulfonic acid, and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 10 hours. The resulting mixture was cooled to 23°C, and 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added. The mixture was stirred at 23°C for 30 minutes, and then separated to separate the organic layer. 20 parts of ion-exchanged water was added to the resulting organic layer, and the mixture was stirred at 23°C for 30 minutes. The organic layer was then separated to separate the organic layer. This water washing procedure was repeated three times. The resulting organic layer was concentrated to obtain 2.71 parts of the compound represented by formula (I-30). MASS (mass spectrometry):375.1[M+H] +

[0234] Example 7: Synthesis of compound represented by formula (I-74) 5.00 parts of the compound represented by formula (I-74-a), 0.008 parts of the compound represented by formula (I-13-c), and 50 parts of toluene were mixed and stirred at 23 ° C. for 30 minutes, and then heated to 100 ° C. 7.05 parts of the compound represented by formula (I-74-b) were added to the resulting mixture at 100 ° C., stirred at 110 ° C. for 2 hours, and then cooled to 23 ° C. 25 parts of ethyl acetate and 30 parts of ion-exchanged water were added to the resulting mixture, and the mixture was stirred at 23 ° C. for 30 minutes, followed by separation to separate the organic layer. 30 parts of ion-exchanged water was added to the recovered organic layer, and the mixture was stirred at 23 ° C. for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=10 / 1) to obtain 2.19 parts of the compound represented by formula (I-74-d). 2.64 parts of the compound represented by formula (I-13-e), 1.62 parts of the compound represented by formula (I-13-f), and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 1 hour. 1.82 parts of the compound represented by formula (I-74-d) were added to the resulting mixture and stirred at 60°C for 1 hour. The resulting reaction mass was cooled to 23°C, and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added. The mixture was stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. 50 parts of ion-exchanged water was added to the recovered organic layer and stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=10 / 1) to obtain 3.47 parts of the compound represented by formula (I-74). MASS (mass spectrometry):429.2[M+H] +

[0235] Example 8: Synthesis of compound represented by formula (I-73) 2.00 parts of the compound represented by formula (I-74), 1.00 parts of p-toluenesulfonic acid, and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 10 hours. The resulting mixture was cooled to 23°C, and 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added. The mixture was stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. 20 parts of ion-exchanged water was added to the resulting organic layer, and the mixture was stirred at 23°C for 30 minutes. The organic layer was then separated and separated to separate the organic layer. This water washing procedure was repeated three times. The resulting organic layer was concentrated, and the concentrated mass was separated using a column (silica gel 60N (spherical, neutral) 100-210 μm; Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 1.19 parts of the compound represented by formula (I-73). MASS (mass spectrometry):373.2[M+H] +

[0236] Example 9: Synthesis of compound represented by formula (I-86) 2.66 parts of the compound represented by formula (I-32-e), 1.62 parts of the compound represented by formula (I-13-f), and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 1 hour. 1.82 parts of the compound represented by formula (I-74-d) were added to the resulting mixture and stirred at 60°C for 1 hour. The resulting reaction mass was cooled to 23°C, and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added. The mixture was stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. 50 parts of ion-exchanged water was added to the recovered organic layer and stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. This water washing procedure was repeated three times. The obtained organic layer was concentrated, and the concentrated mass was separated by a column (silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate=10 / 1) to obtain 3.59 parts of the compound represented by formula (I-86). MASS (mass spectrometry):431.1[M+H] +

[0237] Example 10: Synthesis of compound represented by formula (I-85) 2.00 parts of the compound represented by formula (I-86), 1.00 parts of p-toluenesulfonic acid, and 30 parts of acetonitrile were mixed and stirred at 23°C for 30 minutes, followed by stirring at 60°C for 10 hours. The resulting mixture was cooled to 23°C, and 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added. The mixture was stirred at 23°C for 30 minutes, followed by separation to separate the organic layer. 20 parts of ion-exchanged water was added to the resulting organic layer, and the mixture was stirred at 23°C for 30 minutes. The organic layer was then separated and separated to separate the organic layer. This water washing procedure was repeated three times. The resulting organic layer was concentrated, and the concentrated mass was separated using a column (silica gel 60N (spherical, neutral) 100-210 μm; Kanto Chemical Co., Inc., developing solvent: n-heptane / ethyl acetate = 1 / 1) to obtain 1.07 parts of the compound represented by formula (I-85). MASS (mass spectrometry):375.1[M+H] +

[0238] Resin synthesis The compounds (monomers) used in the synthesis of the resin are shown below. TIFF2026001162000148.tif170165Hereinafter, these monomers will be referred to as "monomer (a1-1-3)" etc. according to their formula numbers.

[0239] Example 11 [Synthesis of Resin A1] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (I-1) 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 (I-1)). 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. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.2 × 10 3 Resin A1 having the following structural units was obtained in a yield of 60%. TIFF2026001162000149.tif49155

[0240] Example 12 [Synthesis of Resin A2] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (I-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 (I-2)). This monomer mixture was then mixed with 1.5 times the total mass of all monomers in methyl isobutyl ketone. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators in amounts of 1.2 mol% and 3.6 mol%, respectively, and the mixture was heated at 73°C for approximately 5 hours. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.0 × 10 3 Resin A2 having the following structural units was obtained in a yield of 63%. TIFF2026001162000150.tif49155

[0241] Example 13 [Synthesis of Resin A3] The monomers used were acetoxystyrene, monomer (a1-1-3), monomer (a1-2-6), monomer (a2-1-3), monomer (a3-4-2), and monomer (I-13). The molar ratio of acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (I-13) was 27:5:35:3:15:15. Methyl isobutyl ketone was then 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, relative to the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. After that, a 25% aqueous solution of tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 12 hours, the layers were separated. The resulting 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 5.1 × 10 3 Resin A3 having the following structural units was obtained in a yield of 78%. JPEG2026001162000151.jpg62163

[0242] Example 14 [Synthesis of Resin A4] The monomers used were acetoxystyrene, monomer (a1-1-3), monomer (a1-2-6), monomer (a2-1-3), monomer (a3-4-2), and monomer (I-14). The molar ratio of acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (I-14) was 27:5:35:3:15:15. Methyl isobutyl ketone was then 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, relative to the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. After that, a 25% aqueous solution of tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 12 hours, the layers were separated. The resulting 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 5.0 × 10 3 Resin A4 having the following structural units was obtained in a yield of 80%. TIFF2026001162000152.tif54163

[0243] Example 15 [Synthesis of Resin A5] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (I-30) 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 (I-30)). 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, relative to the total monomer amount. The mixture was heated at 73°C for approximately 5 hours. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.3 × 10 3 Resin A5 was obtained in a yield of 6 Resin A5 was obtained at 1%. This resin A5 has the following structural units: TIFF2026001162000153.tif38155

[0244] Example 16 [Synthesis of Resin A6] The monomers used were acetoxystyrene, monomer (a1-1-3), monomer (a1-2-6), monomer (a2-1-3), monomer (a3-4-2), and monomer (I-32). The molar ratio of acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (I-32) was 27:5:35:3:15:15. Methyl isobutyl ketone was then 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, relative to the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. After cooling to 23°C, a 25% aqueous solution of tetramethylammonium hydroxide was added to the polymerization reaction solution, and the mixture was stirred for 6 hours and then separated. The resulting 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 A6 having the following structural units was obtained in a yield of 78%. TIFF2026001162000154.tif43161

[0245] Example 17 [Synthesis of Resin A7] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (I-73) 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 (I-73)). 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. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.3 × 10 3 Resin A7 having the following structural units was obtained in a yield of 66%. TIFF2026001162000155.tif45155

[0246] Example 18 [Synthesis of Resin A8] The monomers used were acetoxystyrene, monomer (a1-1-3), monomer (a1-2-6), monomer (a2-1-3), monomer (a3-4-2), and monomer (I-74). The molar ratio of acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (I-74) was 27:5:35:3:15:15. Methyl isobutyl ketone was then 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, relative to the total monomer amount, and the mixture was heated at 73°C for approximately 5 hours. After that, a 25% aqueous solution of tetramethylammonium hydroxide was added to the polymerization reaction solution, and after stirring for 12 hours, the layers were separated. The resulting 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 5.2 × 10 3 Resin A8 having the following structural units was obtained in a yield of 73%. TIFF2026001162000156.tif49163

[0247] Example 19 [Synthesis of Resin A9] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (I-85) 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 (I-85)). 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. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.5 × 10 3 Resin A9 having the following structural units was obtained in a yield of 66%. TIFF2026001162000157.tif38155

[0248] Example 20 [Synthesis of Resin A10] The monomers used were acetoxystyrene, monomer (a1-1-3), monomer (a1-2-6), monomer (a2-1-3), monomer (a3-4-2), and monomer (I-86). The molar ratio of acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (I-86) was 27:5:35:3:15:15. Methyl isobutyl ketone was then 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, relative to the total monomer amount. The mixture was then heated at 73°C for approximately 5 hours. After cooling to 23°C, a 25% aqueous solution of tetramethylammonium hydroxide was added to the polymerization reaction solution, and the mixture was stirred for 6 hours and then separated. The resulting 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 A10 having the following structural units was obtained in a yield of 76%. TIFF2026001162000158.tif36165

[0249] Synthesis Example 1 [Synthesis of Resin AX1] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (a2-2-1) 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 (a2-2-1). 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. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.3 × 10 3 Resin AX1 having the following structural units was obtained in a yield of 65%. TIFF2026001162000159.tif38157

[0250] Synthesis Example 2 [Synthesis of Resin AX2] Monomers (a1-1-3), (a1-2-6), (a2-1-3), (a3-4-2), and (a2-2-x) 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 (a2-2-x). 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. The polymerization reaction mixture was then poured into a large amount of n-heptane to precipitate the resin, which was then filtered and recovered to give a polymer with a weight-average molecular weight of approximately 5.1 × 10 3Resin AX2 having the following structural units was obtained in a yield of 61%. TIFF2026001162000160.tif38157

[0251] <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]

[0252] <Resin> A1 to A10, AX1, AX2: Resin A1 to Resin A10, Resin AX1, Resin AX2 <Acid generator> B1-43: Salt represented by formula (B1-43) (synthesized according to the examples in JP 2016-47815 A) JPEG2026001162000162.jpg4381<quencher> C1: Synthesized by the method described in JP 2011-39502 A TIFF2026001162000163.tif4347<solvent> Propylene glycol monomethyl ether acetate 400 parts Propylene glycol monomethyl ether 150 parts γ-butyrolactone 5 parts

[0253] (Electron beam exposure evaluation of resist composition: butyl acetate development) A 6-inch silicon wafer was treated on a direct hot plate with hexamethyldisilazane at 90°C for 60 seconds. The resist composition was spin-coated onto the silicon wafer so that the film thickness of the composition layer was 0.04 µm. The wafer was then pre-baked on the direct hot plate for 60 seconds at the temperature shown in the "PB" column in Table 1 to form a composition layer. The composition layer formed on the wafer was then irradiated with an electron beam lithography machine ("HL-800D" manufactured by Hitachi, Ltd.). A line and space pattern was directly written by changing the exposure dose stepwise using a laser beam with an energy of 50 keV. After exposure, post-exposure was performed on a hot plate for 60 seconds at the temperature shown in the "PEB" column of Table 1. The composition layer on the silicon wafer was then 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.

[0254] 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]

[0255] A resist composition containing the resin of the present invention provides a resist pattern with excellent line edge roughness (LER), making it suitable for semiconductor microfabrication and extremely useful industrially.

Claims

1. A resin containing a structural unit derived from a compound represented by formula (I) and a structural unit represented by formula (a1-2), Acid generator and A resist composition comprising a carboxylate that generates an acid that is weaker in acidity than the acid generated from the acid generator. [In formula (I), R １ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A １ and A ２ each independently represents a single bond or an alkanediyl group having 1 to 6 carbon atoms. W represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. X １ -CO-O-*, -O-*, -O-CO-*, -O-CO-(CH ２ ) ｍｍ -O-* or -O-(CH ２ ) ｎｎ -CO-O-* (* represents the bonding site with Ar). mm and nn represent 0 or 1. Ar represents an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent. R ２ represents a hydrogen atom or an acid labile group, or R ２ When there are two or more R ２ may be combined together to form a group having an acetal ring structure. n represents an integer of 1 to 3. When n is an integer of 2 or more, a plurality of R ２ may be the same or different.] [In formula (a1-2), L ａ２ is -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 ａ５ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ７ 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 combination thereof. n1 represents an integer of 0 to 10. n1′ represents an integer of 0 to 3.

2. In formula (I), A １ and A ２ 2. The resist composition according to claim 1, wherein is a single bond.

3. In formula (I), X １ 3. The resist composition according to claim 1, wherein is —CO—O—* (* represents a bonding site with Ar).

4. In formula (I), 4. The resist composition according to claim 1, wherein n is 1 or 2.

5. In formula (I), R ２ 5. The resist composition according to claim 1, wherein the acid labile group is a group represented by formula (1a) or a group represented by formula (2a). [In formula (1a), R aa1 , R aa2 and R aa3 each independently represents an alkyl group having 1 to 8 carbon atoms which may have a substituent, an alkenyl group having 2 to 8 carbon atoms which may have a substituent, an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, or R aa1 and R aa2 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. naa represents 0 or 1. * indicates a binding site.] [In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa2’ and R aa3’ are bonded to each other and bonded to -C-X ａ Together with —, it forms a heterocyclic group having 3 to 20 carbon atoms, and —CH contained in the hydrocarbon group and the heterocyclic group ２ - may be replaced by -O- or -S-. X a represents an oxygen atom or a sulfur atom. * indicates a binding site.]

6. R ２ is a hydrogen atom, or n is 2 or more and two or more R ２ Two of the R ２ 6. The resist composition according to claim 1, wherein the groups represented by the formula (I) and (II) are taken together to form a group having an acetal ring structure.

7. In formula (I), n is 2, Two R's ２ 7. The resist composition according to claim 1, wherein each of the groups represents a hydrogen atom.

8. In formula (I), n is 2 or more, Two or more R ２ Of these, two R ２ 7. The resist composition according to claim 6, wherein the groups represented by the formula (I) and (II) are taken together to form a group having an acetal ring structure.

9. In formula (I), 9. The resist composition according to claim 1, wherein Ar represents a benzenediyl group.

10. In formula (I), n is 2, Two -OR ２ are respectively, X １ 10. The resist composition according to claim 9, wherein the benzenediyl groups are bonded to the meta and ortho positions of the benzenediyl group.

11. 11. The resist composition according to claim 1, wherein the resin further comprises a structural unit represented by formula (a2-A). [In formula (a2-A), R 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.]

12. 12. The resist composition according to claim 1, wherein the resin further comprises a structural unit represented by formula (a1-1). [In formula (a1-1), L ａ１ is -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 ａ４ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ６ 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 combination thereof. m1 represents an integer of 0 to 14.

13. (1) a step of applying the resist composition according to any one of claims 1 to 12 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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