Salt, acid generator, resist composition, and method for producing a resist pattern

Abstract

To provide a salt capable of producing a resist pattern having good CD uniformity (CDU) and a resist composition containing the same.SOLUTION: A salt represented by formula (I), an acid generator, and a resist composition containing the same are provided. [In the formula, R1 represents -O-L1-CO-O-R5; L1 represents an alkanediyl group; R5 represents an acid-labile group; Q1 and Q2 each represent F or a perfluoroalkyl group; R11 and R12 each represent H, F or the like; z represents an integer of 0-6; X1 represents *-CO-O-, *-O-CO- or the like; A1 represents a group formed by combining a saturated cyclic hydrocarbon group and an alkanediyl group; and R13 represents an optionally substituted cyclic hydrocarbon group.]SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a salt, an acid generator, a resist composition, and a method for producing a resist pattern.

Background Art

[0002] Patent Document 1 describes a resist composition containing a salt represented by the following formula as an acid generator. TIFF0007696208000001.tif2979 Patent Document 2 describes a resist composition containing a salt represented by the following formula as an acid generator. TIFF0007696208000002.tif2989 Patent Document 3 describes a resist composition containing a salt represented by the following formula as an acid generator. TIFF0007696208000003.tif3692

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a resist composition that forms a resist pattern having better CD uniformity (CDU) than a resist pattern formed from a resist composition containing the above salt.

Means for Solving the Problems

[0005] The present invention includes the following inventions. [1] A salt represented by formula (I). TIFF0007696208000004.tif46116[In formula (I), R 1 represents -O-L 1 -CO-O-R 5 represents. L 1 represents an alkanediyl group having 1 to 6 carbon atoms. R 5 represents an acid-labile group. R 2 , R 3 and R 4 each independently represents a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms, or a hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the hydrocarbon group may be replaced by -O- or -CO-. m2 represents any integer from 0 to 4, and when m2 is 2 or more, a plurality of R 2 may be the same as or different from each other. m3 represents any integer from 0 to 5, and when m3 is 2 or more, a plurality of R 3 may be the same as or different from each other. m4 represents any integer from 0 to 5, and when m4 is 2 or more, a plurality of R 4 may be the same as or different from each other. Q 1 and Q 2 each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. R 11 and R 12 each independently represents a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents any integer from 0 to 6, and when z is 2 or more, a plurality of R 11 and R 12 may be the same as or different from each other. X 1 represents *-CO-O-, *-O-CO-, *-O-CO-O-, or *-O- (where * represents the bonding position to C(R 11 )(R 12 ) or C(Q 1 )(Q 2 )).) represents. A 1 represents a group formed by combining a saturated cyclic hydrocarbon group and an alkanediyl group, and the total number of carbon atoms of the saturated cyclic hydrocarbon group and the alkanediyl group is 4 to 36. Both the saturated cyclic hydrocarbon group and the alkanediyl group may have substituents, and -CH2- contained in the saturated cyclic hydrocarbon group and the alkanediyl group may be replaced by -O-, -S-, -CO- or -SO2-. R 13 represents a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have substituents, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. [2]R 5 is the salt according to [1], wherein [2]R is a group represented by the formula (1a) or a group represented by the formula (2a). TIFF0007696208000005.tif2056[In the formula (1a), R aa1 , R aa2 and R aa3 each independently represents an alkyl group having 1 to 8 carbon atoms which may have substituents, an alkenyl group having 2 to 8 carbon atoms which may have substituents, an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have substituents or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have substituents, or R aa1 and R aa2 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. * represents a bond. TIFF0007696208000006.tif2059[In the 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 to form a heterocyclic group having 3 to 20 carbon atoms together with the -C-X a - to which they are bonded, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-. Xa represents an oxygen atom or a sulfur atom. * represents a bond.] [3]A 1 is *-L 2 -CO-O-(L 2 represents a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms or a group combining a cyclic hydrocarbon group having 3 to 18 carbon atoms and an alkanediyl group having 1 to 4 carbon atoms. -CH2- contained in the saturated cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. * is the bond with X 1 and represents the bond with X.) or *-L 21 -W 1 -L 22 -CO-O-L 23 -(W 1 represents a divalent saturated cyclic hydrocarbon group which may have a substituent. -CH2- contained in the saturated cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. L 21 , L 22 and L 23 each independently represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. * is the bonding site with X 1 and represents the salt according to [1] or [2]. [4]L 2 and W 1 are the group represented by the following formula (L 2 -1), formula (L 2 -2), formula (L 2 -3) or formula (L 2 -4) (* represents a bond.) and represents the salt according to [3]. TIFF0007696208000007.tif3096[5]X 1 is *-CO-O- and represents the salt according to any one of [1] to [4]. [6]m3 is any integer from 1 to 2, m4 is any integer from 0 to 2, R 3 and R4 One of them is a salt according to any one of [1] to [5], which is a fluorine atom, an iodine atom or trifluoromethyl. [7] m3 is any integer from 1 to 2, m4 is any integer from 0 to 2, R 3 and R 4 One of them is -O-L 1 -CO-O-R 5 and A plurality of R 5 may be the same as or different from each other, which is a salt according to any one of [1] to [5]. [8] m2 is 1 or 2, A plurality of R 2 At least one of them is -O-L 1 -CO-O-R 5 and A plurality of R 5 may be the same as or different from each other, which is a salt according to any one of [1] to [7]. [9] An acid generator containing a salt according to any one of [1] to [8].

[10] A resist composition containing the acid generator described in [9] and a resin having an acid-labile group.

[11] The resist composition according to

[10] , wherein the resin having an acid-labile group contains at least one selected from the group consisting of a structural unit represented by the formula (a1-1) and a structural unit represented by the formula (a1-2). TIFF0007696208000008.tif49107 [In the formula (a1-1) and the formula (a1-2), L a1 and L a2 each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents any integer from 1 to 7, and * represents a bond to -CO-. R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a6 and R a7Each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these. m1 represents any integer from 0 to 14. n1 represents any integer from 0 to 10. n1’ represents any integer from 0 to 3. The resist composition according to

[10] or

[11] , wherein the resin having an acid-labile group contains a structural unit represented by the formula (a2-A). TIFF0007696208000009.tif5259[In the 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 represents a single bond or * -X a51 -(A a52 -X a52 ) nb -, and * represents a bond to the carbon atom to which -R a50 is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represent -O-, -CO-O-, or -O-CO-. nb represents 0 or 1. mb represents any integer from 0 to 4. When mb is any integer of 2 or more, a plurality of R a51 may be the same as or different from each other.

[13] The resist composition according to any one of

[10] to

[12] , further containing a salt that generates an acid having a lower acidity than the acid generated from the acid generator.

[14] (1) A step of applying the resist composition according to any one of

[10] to

[13] onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, A method for manufacturing a resist pattern including these steps.

Effect of the Invention

[0006] By using the resist composition containing the salt of the present invention, a resist pattern can be manufactured with good CD uniformity (CDU).

Mode for Carrying Out the Invention

[0007] In this specification, the “(meth)acrylic monomer” means at least one selected from the group consisting of monomers having a structure of “CH2=CH-CO-” and monomers having a structure of “CH2=C(CH3)-CO-”. Similarly, “(meth)acrylate” and “(meth)acrylic acid” mean “at least one selected from the group consisting of acrylate and methacrylate” and “at least one selected from the group consisting of acrylic acid and methacrylic acid”, respectively. When a structural unit having “CH2=C(CH3)-CO-” or “CH2=CH-CO-” is exemplified, structural units having both groups are similarly exemplified. Also, among the groups described in this specification, those that can take both a linear structure and a branched structure may be either of them. The “combined group” means a group formed by bonding two or more of the exemplified groups, and the valences of these groups may be appropriately changed depending on the bonding form. “Derived from” or “induced” means that the polymerizable C=C bond contained in the molecule becomes a -C-C- group by polymerization. When stereoisomers exist, all stereoisomers are included.

[0008] The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)"). Among salts (I), the negatively charged side may be referred to as "anion (I)", and the positively charged side may be referred to as "cation (I)". TIFF0007696208000010.tif46116[Wherein all the symbols have the same meanings as described above.]

[0009] In formula (I), R 1 The alkandiyl group in L 1 constituting includes linear alkandiyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group; and branched alkandiyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group and the like. L 1 is preferably an alkandiyl group having 1 to 3 carbon atoms, and more preferably a methylene group.

[0010] R 1 The acid-labile group of R 5 constituting means a group that, when contacted with an acid (for example, trifluoromethanesulfonic acid), the group represented by R 5 is eliminated to form a carboxy group. As the acid-labile group, 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)") are preferable. TIFF0007696208000011.tif2056[In formula (1a), R aa1 , R aa2 and R aa3each 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 an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. * represents a bond.] TIFF0007696208000012.tif2059[In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa2’ and R aa3’ are bonded to each other to form a heterocyclic group having 3 to 20 carbon atoms together with the -C-X a -, and the -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. * represents a bond.]

[0011] R aa1 、R aa2 and R aa3 Examples of the alkyl group of R 、R aa1 、R aa2 and R aa3 include a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 6, more preferably 1 to 3. R aa1 、R aa2 and R aa3The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include, for example, decahydronaphthyl group, adamantyl group, norbornyl group and the following group (* represents a bond). R aa1 , R aa2 and R aa The number of carbon atoms of the alicyclic hydrocarbon group of R TIFF0007696208000013.tif9159R aa1 , R aa2 and R aa3 Examples of the aromatic hydrocarbon group of R

[0012] Examples of the substituent of the alkyl group having 1 to 8 carbon atoms which may have a substituent include an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and an aromatic hydrocarbon group 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 an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and an aromatic hydrocarbon group 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 an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, and an aromatic hydrocarbon group 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 an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, and an alicyclic hydrocarbon group having 3 to 20 carbon atoms. More specifically, a group combining an alkyl group and an alicyclic hydrocarbon group (an alkylcycloalkyl group or a cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornil group, a cyclohexylmethyl group, an adamantylmethyl group, a norbornylethyl group, etc.), 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, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as a phenylcyclohexyl group, etc. are included. naa is preferably 1.

[0013] R aa1 and R aa2 When they are bonded to each other to form an alicyclic hydrocarbon group, examples of -C(R aa1 )(R aa2 )(R aa3 ) include the following groups. The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms, more preferably 3 to 12 carbon atoms. * represents a bond to -O-. TIFF0007696208000014.tif31145

[0014] Examples of the group represented by formula (1a) include a 1,1,1-trialkyl group (in formula (1a), R aa1 , R aa2 and R aa are alkyl groups, preferably a tert-butoxycarbonyl group), a 2-alkyladamantan-2-yl group (in formula (1a), R aa1 , R aa2 and the carbon atom to which they are attached form an adamantyl group, and R aa3 is an alkyl group), and a 1-(adamantan-1-yl)-1,1-dialkyl group (in formula (1a), R aa1 and R aa2 are alkyl groups, and R aa3 is an adamantyl group).

[0015] Examples of the hydrocarbon groups for R aa1' , R aa2' and R aa3' include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. Examples of the alkyl group and the alicyclic hydrocarbon group are the same as those exemplified for R aa1 , R aa2 and R aa . Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, and phenanthryl group. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., alkylcycloalkyl group or cycloalkylalkyl 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. R aa2' and R aa3'are bonded to each other and the carbon atom to which they are bonded and X a When forming a heterocyclic group together with -C(R aa1' )(R aa2' )-X a -(R aa3' ), the following groups may be mentioned. * represents a bond. TIFF0007696208000015.tif22152R aa1' and R aa2' Among them, at least one is preferably a hydrogen atom.

[0016] Specific examples of the acid-labile group (1a) include the following groups. * represents a bond. TIFF0007696208000016.tif69152

[0017] Specific examples of the acid-labile group (2a) include the following groups. * represents a bond. TIFF0007696208000017.tif68167R 1 The bonding position of to the benzene ring of S + may be any of the ortho, meta, and para positions with respect to, but the para position is preferred.

[0018] R 2 R 3 and R 4 The C1-C4 fluorinated alkyl group of and represents an alkyl group having 1 to 4 carbon atoms and having a fluorine atom, and a C1-C4 perfluoroalkyl group (trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group), and 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, and 3,3,4,4,4-pentafluorobutyl group and the like may be mentioned. R 2 R 3 and R 4 Examples of the C1-C18 hydrocarbon group of and include chain hydrocarbon groups such as alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, 2-ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group and the like. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the like. Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group and the like.

[0019] Examples of the group formed by combination include a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (for example, aromatic hydrocarbon group - alkanediyl group - *, alkyl group - aromatic hydrocarbon group - *), a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group (for example, alicyclic hydrocarbon group - alkanediyl group - *, alkyl group - alicyclic hydrocarbon group - *), and a group formed by combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (for example, aromatic hydrocarbon group - alicyclic hydrocarbon group - *, alicyclic hydrocarbon group - aromatic hydrocarbon group - *). * represents a bonding site. Examples of the aromatic hydrocarbon group - alkanediyl group - * include aralkyl groups such as benzyl group, phenethyl group and the like. Examples of the alkyl group - aromatic hydrocarbon group - * include tolyl group, xylyl group, cumenyl group and the like. Examples of the alicyclic hydrocarbon group - alkanediyl group - * include cycloalkylalkyl groups such as cyclohexylmethyl group, cyclohexylethyl group, 1-(adamantan-1-yl)methyl group, 1-(adamantan-1-yl)-1-methylethyl and the like. Examples of the alkyl group - alicyclic hydrocarbon group - * include cycloalkyl groups having an alkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, 2-alkyladamantan-2-yl group and the like. Examples of the aromatic hydrocarbon group - alicyclic hydrocarbon group - * include a phenylcyclohexyl group and the like. Examples of the alicyclic hydrocarbon group - aromatic hydrocarbon group - * include a cyclohexylphenyl group and the like. In the combination, two or more kinds of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined with each other. Further, any of these groups may be bonded to the benzene ring. Examples of the group in which -CH2- contained in the hydrocarbon group is replaced by -O- or -CO- include a hydroxy group; a carboxy group; an alkoxy group having 1 to 11 carbon atoms such as a methoxy group, an ethoxy group, and a butoxy group; a cycloalkoxy group having 3 to 11 carbon atoms such as a cyclohexyloxy group; a cycloalkylalkoxy group having 4 to 11 carbon atoms such as a cyclohexylmethoxy group; an alkylcarbonyl group having 2 to 12 carbon atoms such as an acetyl group; an alkoxycarbonyl group having 2 to 11 carbon atoms such as a methoxycarbonyl group; an alkylcarbonyloxy group having 2 to 11 carbon atoms such as an acetyloxy group; an alkoxycarbonyloxy group having 2 to 11 carbon atoms such as a butoxycarbonyloxy group; an aromatic hydrocarbon group-carbonyl-oxy group having 7 to 11 carbon atoms such as a benzoyloxy group.

[0020] m2 is preferably any integer from 0 to 2, more preferably 0 or 2. m3 and m4 are each independently preferably any integer from 0 to 2, more preferably 0 or 1. R 2 is a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), -O-L 1 -CO-O-R 5 (L 1 and R 5 have the same meanings as defined above), preferably an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-) or -O-L 1 -CO-O-R 5 (L1 and R 5 is more preferably the same as described above), and is an alkyl group having 1 to 4 carbon atoms or -O-L 1 -CO-O-R 5 (L 1 and R 5 is more preferably the same as described above). When m2 is 1 or 2, at least one of the plurality of R 2 is preferably -O-L 1 -CO-O-R 5 . R 3 and R 4 are each independently a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkyl group may be replaced by -O- or -CO-), -O-L 1 -CO-O-R 5 (L 1 and R 5 is preferably the same as described above), a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (the -CH2- contained in the alkyl group may be replaced by -O- or -CO-), -O-L 1 -CO-O-R 5 (L 1 and R 5 is more preferably the same as described above), and more preferably a fluorine atom, an iodine atom or a perfluoroalkyl group having 1 to 4 carbon atoms. Furthermore, when m3 is any integer from 1 to 2 and m4 is an integer from 0 to 2, either one of R 3 and R 4 is more preferably a fluorine atom, an iodine atom, a trifluoromethyl group or -O-L 1 -CO-O-R 5 (L 1 and R 5 is more preferably the same as described above). In addition, in formula (I), when there are a plurality of R 5 , the plurality of R 5 may be the same as or different from each other.

[0021] Examples of the cation of salt (I) include cations represented by the following formulas (I-c-1) to (I-c-26). TIFF0007696208000018.tif82157

[0022] TIFF0007696208000019.tif212163

[0023] TIFF0007696208000020.tif235160

[0024] Among them, cations represented by formulas (I-c-1) to (I-c-9), formula (I-c-16), formula (I-c-19), formula (I-c-20), and formula (I-c-25) are preferred, cations represented by formulas (I-c-1) to (I-c-6), formula (I-c-16), formula (I-c-19), formula (I-c-20), and formula (I-c-25) are more preferred, cations represented by formulas (I-c-1) to (I-c-4), formula (I-c-16), formula (I-c-19), formula (I-c-20), and formula (I-c-25) are even more preferred, and cations represented by formula (I-c-1), formula (I-c-3), formula (I-c-4), formula (I-c-16), formula (I-c-19), formula (I-c-20), and formula (I-c-25) are even more preferably.

[0025] In formula (I), Q 1 、Q 2 、R 11 and R 12 Examples of the perfluoroalkyl group of include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group, perfluorohexyl group and the like. Q 1 and Q 2 are each independently preferably a trifluoromethyl group or a fluorine atom, and more preferably a fluorine atom. R 11 and R 12Each is independently preferably a hydrogen atom or a fluorine atom. z is preferably 0 or 1. X 1 is preferably *-CO-O- or *-O-CO-O-, more preferably *-CO-O- (* represents a bond with C(R 11 )(R 12 ) or C(Q 1 )(Q 2 )).

[0026] A 1 represents a group formed by combining a saturated cyclic hydrocarbon group and an alkanediyl group. The saturated cyclic hydrocarbon group may be monocyclic, polycyclic or spirocyclic. For example, the following groups can be mentioned. The bond can be at any position. TIFF0007696208000021.tif41166

[0027] A 1 The saturated cyclic hydrocarbon group contained in A preferably has 3 to 35 carbon atoms, more preferably 3 to 34 carbon atoms, still more preferably 3 to 18 carbon atoms, and even more preferably 3 to 16 carbon atoms. A 1 There may be one or more saturated cyclic hydrocarbon groups contained in A. Examples of the saturated cyclic hydrocarbon group include monocyclic saturated cyclic hydrocarbon groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, etc., and polycyclic saturated cyclic hydrocarbon groups such as a norbornyl group, a group represented by the following formula (A 1 -1), a group represented by the formula (A 1 -2), a group represented by the formula (A 1 -3), etc. are more preferable, and a cyclohexyl group, a group represented by the following formula (A 1 -1), a group represented by the following formula (A 1 -2) or a group represented by the formula (A 1 -3) are even more preferable, and a group represented by the following formula (A 1 -1), a group represented by the following formula (A 1 -2) or a group represented by the formula (A 1It is more preferably a group represented by -3), and more preferably a group represented by the following formula (A 1 It is even more preferably a group represented by -2). The bond can be at any position. TIFF0007696208000022.tif2966

[0028] The saturated cyclic hydrocarbon group may have -CH2- contained in the saturated cyclic hydrocarbon group replaced by -O-, -S-, -SO2- or -CO-. When -CH2- contained in the saturated cyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, the number of carbon atoms before replacement is taken as the number of carbon atoms of the saturated cyclic hydrocarbon group. Examples of the group in which -CH2- contained in the saturated cyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. The bond can be at any position. TIFF0007696208000023.tif74150 Among them, the following groups are preferred. TIFF0007696208000024.tif19132

[0029] Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc.

[0030] -CH2- contained in the alkanediyl group may be replaced by -O-, -S-, -CO- or -SO2-. When -CH2- contained in the alkanediyl group is replaced by -O-, -S-, -CO- or -SO2-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the alkanediyl group. Examples of the group in which -CH2- contained in the alkanediyl group is replaced by -O- or -CO- include a carbonyloxy group (a group in which -CH2-CH2- contained in an ethylene group is replaced by -O-CO-), an alkanediyl-oxy group (a group in which -CH2- contained in an alkanediyl group is replaced by -O-), an alkanediyl-oxycarbonyl group (a group in which -CH2-CH2- contained in an alkanediyl group is replaced by -O-CO-), an alkanediyl-carbonyl group (a group in which -CH2- contained in an alkanediyl group is replaced by -CO-), an alkanediyl-carbonyl-oxy group (a group in which -CH2-CH2- contained in an alkanediyl group is replaced by -CO-O-), and the like. Examples of the alkanediyl-oxy group include a methylene-oxy group, an ethylene-oxy group, a propylene-oxy group, a butylene-oxy group, a pentanediyl-oxy group, a hexanediyl-oxy group, an octanediyl-oxy group, a 2-ethylhexanediyl-oxy group, a nonanediyl-oxy group, a decanediyl-oxy group, an undecanediyl-oxy group, and the like. The alkanediyl-oxycarbonyl group, the alkanediyl-carbonyl group and the alkanediyl-carbonyl-oxy group represent groups in which a carbonyl group or a carbonyloxy group is bonded to the above-described alkanediyl group or alkanediyl-oxy group. Examples of the alkanediyl-oxycarbonyl group include a methylene-oxycarbonyl group, an ethylene-oxycarbonyl group, a butylene-oxycarbonyl group, and the like. Examples of the alkanediyl-carbonyl group include an ethylene-carbonyl group, a propylene-carbonyl group, a butylene-carbonyl group, and the like. Examples of the alkanediyl-carbonyl-oxy group include an ethylene-carbonyl-oxy group, a propylene-carbonyl-oxy group, a butylene-carbonyl-oxy group, and the like.

[0031] The total number of carbon atoms in the saturated cyclic hydrocarbon group and the alkanediyl group is from 4 to 36, preferably from 4 to 34, more preferably from 6 to 32, and still more preferably from 8 to 30. Further, these saturated cyclic hydrocarbon groups and alkanediyl groups may each have a substituent.

[0032] A 1 In the group formed by combining the saturated cyclic hydrocarbon group of A and the alkanediyl group, it is preferable that -CH2- contained in the alkanediyl group is replaced by -O-, -S-, -CO- or -SO2-. In this case, one -CH2- may be replaced, but those in which two or more -CH2- are replaced are preferred. For example, those replaced by one -O-, -S-, -CO- or -SO2-, those replaced by two -O-, -S- or -CO-, those replaced by one or more -O- or -S- and one or more -CO- or -SO2-, etc. may be mentioned. Specifically, -O-, -CO-, -O-CO-, -CO-O-, -O-CO-O-, etc. may be mentioned. Among them, -O-CO-, -CO-O-, -O-CO-O- are preferred. For example, A 1 is *-L 2 -CO-O-, *-L 2 -O-CO-, *-L 2 -O-CO-O-, *-L 21 -W 1 -L 22 -CO-O-L 23 -, *-L 21 -W 1 -L 22 -O-CO-L 23 - or *-L 21 -W 1 -L 22 -O-CO-O-L 23 - are mentioned. * represents the bonding site with X 1 and. Here, L 2represents a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms or a group formed by combining a saturated cyclic hydrocarbon group having 3 to 18 carbon atoms and an alkanediyl group having 1 to 4 carbon atoms, wherein -CH2- contained in the saturated cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. L 2 Examples of the saturated cyclic hydrocarbon group and the alkanediyl group in 2 include the same groups as those exemplified above. L 2 L 2 is preferably a polycyclic divalent saturated cyclic hydrocarbon group having 6 to 12 carbon atoms (the saturated cyclic hydrocarbon group may have a substituent, and -CH2- contained in the saturated cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), more preferably a polycyclic divalent saturated alicyclic hydrocarbon group having 7 to 11 carbon atoms ( -CH2- contained in the saturated alicyclic hydrocarbon group may be replaced by -O- or -CO-), still more preferably a group represented by the following formula (L 2 -1), a group represented by the formula (L 2 -2), a group represented by the formula (L 2 -3), or a group represented by the formula (L 2 -4), and even more preferably a group represented by the formula (L TIFF0007696208000025.tif3096 Also, W 1 represents a divalent saturated cyclic hydrocarbon group, the saturated cyclic hydrocarbon group may have a substituent, and -CH2- contained in the saturated cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. L 21 L 22 and L 23 each independently represent a single bond or an alkanediyl group having 1 to 4 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. In this case, the saturated cyclic hydrocarbon group in W 1 , and L 21 L 22 and L 23Examples of the alkanediyl group in [it] include the same groups as those exemplified above. W 1 is preferably a polycyclic divalent saturated cyclic hydrocarbon group having 6 to 12 carbon atoms (the saturated cyclic hydrocarbon group may have a substituent, and -CH2- contained in the saturated cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), more preferably a polycyclic divalent saturated alicyclic hydrocarbon group having 7 to 11 carbon atoms ( -CH2- contained in the saturated alicyclic hydrocarbon group may be replaced by -O- or -CO-), still more preferably a group represented by the above formula (L 2 -1), a group represented by the formula (L 2 -2), a group represented by the formula (L 2 -3), or a group represented by the formula (L 2 -4), and even more preferably a group represented by the formula (L 2 -2). L 21 、L 22 and L 23 are each independently preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms ( -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, A 1 is preferably *-L 2 -CO-O- or *-L 21 -W 1 -L 22 -CO-O-L 23 -, and more preferably *-L 2 -CO-O-.

[0033] The saturated cyclic hydrocarbon group and the alkanediyl group in A 1 may have one or more substituents. A 1Examples of the substituents that the saturated cyclic hydrocarbon group and the alkanediyl group in [substance] may have include a halogen atom, a hydroxy group, a cyano group, a carboxy group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyloxy group having 2 to 13 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a group formed by combining these groups, etc.

[0034] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. Examples of the alkyl group having 1 to 12 carbon atoms 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. 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, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, a dodecyloxy group, etc. Examples of the alkoxycarbonyl group having 2 to 13 carbon atoms include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, a pentyloxycarbonyl group, a hexyloxycarbonyl group, an octyloxycarbonyl group, a 2-ethylhexyloxycarbonyl group, a nonyloxycarbonyl group, a decyloxycarbonyl group, an undecyloxycarbonyl group, a dodecyloxycarbonyl group, etc. Examples of the alkylcarbonyl group having 2 to 13 carbon atoms include an acetyl group, a propionyl group, a butyryl group, etc. Examples of the alkylcarbonyloxy group having 2 to 13 carbon atoms include an acetyloxy group, a propionyloxy group, a butyryloxy group, etc. Examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornyl group, etc. Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group.

[0035] Examples of the combined group include a group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkyl group having 1 to 12 carbon atoms, a group formed by combining a hydroxy group and an alkyl group having 1 to 12 carbon atoms, a group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms, a group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkylcarbonyl group having 2 to 13 carbon atoms, a group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkylcarbonyloxy group having 2 to 13 carbon atoms, and a group formed by combining an alkyl group having 1 to 12 carbon atoms and an aromatic hydrocarbon group having 6 to 10 carbon atoms. Examples of the group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkyl group having 1 to 12 carbon atoms include alkoxyalkyl groups having 2 to 24 carbon atoms, such as a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, and an ethoxymethyl group. Examples of the group formed by combining 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 group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms include alkoxyalkoxy groups having 2 to 24 carbon atoms, such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, and an ethoxyethoxy group. Examples of the group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkylcarbonyl group having 2 to 13 carbon atoms include alkoxyalkylcarbonyl groups having 3 to 25 carbon atoms, such as a methoxyacetyl group, a methoxypropionyl group, an ethoxyacetyl group, and an ethoxypropionyl group. Examples of the group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkylcarbonyloxy group having 2 to 13 carbon atoms include alkoxyalkylcarbonyloxy groups having 2 to 24 carbon atoms, such as a methoxyacetyloxy group, a methoxypropionyloxy group, an ethoxyacetyloxy group, and an ethoxypropionyloxy group. Examples of the group formed by combining 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.

[0036] The substituent is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 12 carbon atoms, a hydroxyalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkyloxycarbonyloxy group having 2 to 13 carbon atoms, an alkoxyalkyl group having 2 to 24 carbon atoms, an alkoxyalkoxy group having 2 to 24 carbon atoms or a cyano group, and more preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

[0037] A 1 Examples thereof include the following groups. * and ** represent bonds, and * represents a bond to X 1 represents a bond to. TIFF0007696208000026.tif116165

[0038] R 13 The cyclic hydrocarbon group of R may be monocyclic, polycyclic or spiro, and may be saturated or unsaturated, and examples thereof include an alicyclic hydrocarbon group, an aromatic hydrocarbon group and a group combining these. Examples of the alicyclic hydrocarbon group include the following groups. The bond can be at any position. TIFF0007696208000027.tif41166Specifically, monocyclic cycloalkyl groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a cyclododecyl group, and polycyclic cycloalkyl groups such as a norbornyl group and an adamantyl group are included. Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group and a phenanthryl group. The number of carbon atoms of the cyclic hydrocarbon group is preferably 3 to 18, and more preferably 3 to 16. R 13When -CH2- contained in the cyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the cyclic hydrocarbon group. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. The bonding position can be at any position. TIFF0007696208000028.tif74150

[0039] R 13 The alicyclic hydrocarbon group and the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -SO2- or -CO- in are preferably groups represented by formulas (Y1) to (Y41), more preferably groups represented by any of formulas (Y1) to (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), and formulas (Y39) to (Y43), and even more preferably groups represented by formula (Y3), formula (Y4), formula (Y11), formula (Y15), formula (Y18), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42) or formula (Y43). TIFF0007696208000029.tif85168

[0040] R 13 The cyclic hydrocarbon group in has 3 to 24 carbon atoms in total and may further have one or more substituents. Examples of the substituent include a hydroxy group, a halogen atom, a cyano group, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyloxy group having 2 to 13 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a group combining these. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group and the like. Examples of the alkoxy group having 1 to 12 carbon atoms include 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 and the like. The alkoxycarbonyl group having 2 to 13 carbon atoms, the alkylcarbonyl group having 2 to 13 carbon atoms and the alkylcarbonyloxy group having 2 to 13 carbon atoms represent groups in which a carbonyl group or a carbonyl-oxy group is bonded to the above-described alkyl group or alkoxy group. Examples of the alkoxycarbonyl group having 2 to 13 carbon atoms include methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group having 2 to 13 carbon atoms include acetyl group, propionyl group, butyryl group and the like. Examples of the alkylcarbonyloxy group having 2 to 13 carbon atoms include acetyloxy group, propionyloxy group, butyryloxy group and the like. The alicyclic hydrocarbon group having 3 to 16 carbon atoms may be either monocyclic or polycyclic, and examples thereof include the groups shown below. ** represents a bond to an aromatic hydrocarbon group. Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include phenyl group, naphthyl group and the like.

[0041] R 13 Examples of the combined groups in the substituent of R include a group formed by combining a hydroxy group and an alkyl group having 1 to 12 carbon atoms, a group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms, a group formed by combining an alkyl group having 1 to 12 carbon atoms and an aromatic hydrocarbon group having 6 to 10 carbon atoms and the like. Examples of the group formed by combining a hydroxy group and an alkyl group having 1 to 12 carbon atoms include hydroxyalkyl groups having 1 to 12 carbon atoms such as hydroxymethyl group, hydroxyethyl group and the like. Examples of the group formed by combining an alkoxy group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms include alkoxyalkoxy groups having 2 to 24 carbon atoms such as ethoxyethoxy group. Examples of the group formed by combining 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 benzyl group.

[0042] R 13 The substituent that R has is preferably an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, a hydroxy group or a halogen atom, and more preferably an alkyl group having 1 to 4 carbon atoms, a hydroxy group or a fluorine atom.

[0043] R 13 The cyclic hydrocarbon group of R (the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have an alkyl group having 1 to 4 carbon atoms, a hydroxy group or a fluorine atom (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). Specifically, preferably, a cyclopentyl group having an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group having an alkyl group having 1 to 4 carbon atoms, an adamantyl group having an alkyl group having 1 to 4 carbon atoms, a hydroxyadamantyl group, an adamantanone group, an adamantanlactone ring group or a norbornanelactone ring group, and more preferably an adamantyl group having an alkyl group having 1 to 4 carbon atoms, a hydroxyadamantyl group or an adamantanone group.

[0044] Examples of the anion (I) include anions represented by the following formulas (Ia-1) to (Ia-20). Among them, anions represented by the formulas (Ia-1) to (Ia-12), (Ia-18), and (Ia-19) are preferred, and anions represented by the formulas (Ia-1), (Ia-2), (Ia-8) to (Ia-12), and (Ia-19) are more preferred. TIFF0007696208000031.tif185141

[0045] TIFF0007696208000032.tif162149

[0046] Examples of the salt (I) include the salts described in Table 1. For example, in Table 1, the salt (I-1) is a salt composed of the anion represented by the formula (Ia-1) and the cation represented by the formula (b2-c-1), and means the following salts. TIFF0007696208000033.tif24110

[0047] [Table 1] TIFF0007696208000035.tif223154 TIFF0007696208000036.tif223154 TIFF0007696208000037.tif223154 TIFF0007696208000038.tif223154 TIFF0007696208000039.tif223154 TIFF0007696208000040.tif223154 TIFF0007696208000041.tif223154 TIFF0007696208000042.tif223154 TIFF0007696208000043.tif223154 TIFF0007696208000044.tif223154 TIFF0007696208000045.tif223154 TIFF0007696208000046.tif223154 Among them, salt (I) includes salt (I-1), salt (I-2), salt (I-8) to salt (I-12), salt (I-19), salt (I-21), salt (I-22), salt (I-28) to salt (I-32), salt (I-39), salt (I-41), salt (I-42), salt (I-48) to salt (I-52), salt (I-59), salt (I-61), salt (I-62), salt (I-68) to salt (I-72), salt (I-79), salt (I-81), salt (I-82), salt (I-88) to salt (I-92), salt (I-99), salt (I-101), salt (I-102), salt (I-108) to salt (I-112), salt (I-119), salt (I-121), salt (I-122), salt (I-128) to salt (I-132), salt (I-139), salt (I-141), salt (I-142), salt (I-148) to salt (I-152), salt (I-159), salt (I-161), salt (I-162), salt (I-168) to salt (I-172), salt (I-179), salt (I-181), salt (I-182), salt (I-188) to salt (I-192), salt (I-199), salt (I-201), salt (I-202), salt (I-208) to salt (I-212), salt (I-219), salt (I-221), salt (I-222), salt (I-228) to salt (I-232), salt (I-239), salt (I-241), salt (I-242), salt (I-248) to salt (I-252), salt (I-259), salt (I-261), salt (I-262), salt (I-268) to salt (I-272), salt (I-279), salt (I-281), salt (I-282), salt (I-288) to salt (I-292), salt (I-299), salt (I-301), salt (I-302), salt (I-308) to salt (I-312), salt (I-319), salt (I-321), salt (I-322), salt (I-328) to salt (I-332), salt (I-339), salt (I-341), salt (I-342), salt (I-348) to salt (I-352), salt (I-359), salt (I-361), salt (I-362), salt (I-368) to salt (I-372), salt (I-379), salt (I-381), salt (I-382), salt (I-388) to salt (I-392), salt (I-399), salt (I-401), salt (I-402), salt (I-408) to salt (I-412), salt (I-419), salt (I-421), salt (I-422), salt (I-428) to salt (I-432), salt (I-439), salt (I-441), salt (I-442)Salts (I-448) to (I-452), salt (I-459), salt (I-461), salt (I-462), salts (I-468) to (I-472), salt (I-479), salt (I-481), salt (I-482), salts (I-488) to (I-492), salt (I-499), salt (I-501), salt (I-502), salts (I-508) to (I-512), and salt (I-519) are preferred.

[0048] <Method for Producing Salt (I)> Salt (I) can be produced by reacting a salt represented by formula (I-a) and a salt represented by formula (I-b) in a solvent. TIFF0007696208000047.tif86148[In the formula, all symbols have the same meanings as described above.] Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, water, and the like. The reaction temperature is usually 15°C to 80°C, and the reaction time is usually 0.5 to 24 hours.

[0049] Examples of the salt represented by formula (I-a) include salts represented by the following formula, which can be easily obtained from the market and can also be easily produced by known production methods. TIFF0007696208000048.tif145159

[0050] Examples of the salt represented by formula (I-b) include salts represented by the following, which can be easily obtained from the market and can also be easily produced by known production methods. TIFF0007696208000049.tif24133

[0051] <Acid Generator> The acid generator of the present invention is an acid generator containing salt (I). It may contain one kind of salt (I) or two or more kinds of salt (I). In addition to the salt (I), the acid generator of the present invention may contain an acid generator known in the resist field (hereinafter sometimes referred to as "acid generator (B)"). The acid generator (B) may be used alone or in combination of two or more.

[0052] Either a nonionic or an ionic acid generator may be used as the acid generator (B). Examples of the nonionic acid generator include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxy ketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), etc. Representative examples of the ionic acid generator include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of the anion of the onium salt include sulfonic acid anion, sulfonylimide anion, sulfonylmethide anion, etc.

[0053] As the acid generator (B), compounds that generate an acid upon irradiation described in, for example, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc. can be used. Further, compounds produced by known methods may also be used. The acid generator (B) may be used in combination of two or more.

[0054] The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a salt represented by the formula (B1) (hereinafter sometimes referred to as "acid generator (B1)". However, the salt (I) is excluded.). TIFF0007696208000050.tif2963[In the 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 a hydrogen atom contained in the divalent saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. Y represents an optionally substituted methyl group or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S(O)2- or -CO-. Z1 + represents an organic cation.

[0055] Q b1 and Q b2 Examples of the perfluoroalkyl group represented by Q and Q include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Q b1 and Q b2 are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably both are fluorine atoms.

[0056] L b1 Examples of the divalent saturated hydrocarbon group in L include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and a group formed by combining two or more of these groups. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group; Branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; Monocyclic divalent alicyclic saturated hydrocarbon groups that are cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; Polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. can be mentioned.

[0057] L b1 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO- include groups represented by any of formula (b1-1) to formula (b1-3). In the groups represented by formula (b1-1) to formula (b1-3) and the groups represented by formula (b1-4) to formula (b1-11) which are specific examples thereof, * and ** represent bonds, and * represents a bond to -Y.

[0058] TIFF0007696208000051.tif26117[In formula (b1-1), L b2represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L b2 and L b3 have a total carbon number of 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 the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L b4 and L b5 have a total carbon number of 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 the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups. L b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L b6 and L b7 have a total carbon number of 23 or less. * and ** represent bonds, and * represents the bond with Y.

[0059] In the groups represented by formula (b1-1) to formula (b1-3), when -CH2- contained in the saturated hydrocarbon group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the saturated hydrocarbon group. Examples of the divalent saturated hydrocarbon group include those similar to the divalent saturated hydrocarbon group of L b1 as described above.

[0060] L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted by fluorine atoms. 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 the hydrogen atoms contained in the saturated hydrocarbon group may be substituted by fluorine atoms. L b7 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted by fluorine atoms or hydroxy groups, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-.

[0061] L b1 As the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO-, the group represented by formula (b1-1) or formula (b1-3) is preferred. Examples of the group represented by formula (b1-1) include the groups represented by formula (b1-4) to formula (b1-8), respectively. TIFF0007696208000052.tif48120 [In formula (b1-4), L b8represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups. In formula (b1-5), L b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b10 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups. However, b9 L b10 and In formula (b1-6), L b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups. However, b11 L b12 and In formula (b1-7), L b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. L b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the hydrogen atoms contained in the divalent saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups. However, b13 L b15 to In formula (b1-8), L b16represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced 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, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted by a fluorine atom or a hydroxy group. However, L b16 ~L b18 The total number of carbon atoms is 19 or less. L b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. * and ** represent a bond, and * represents a bond with Y.

[0062] Examples of the group represented by the formula (b1-3) include the groups represented by the formulas (b1-9) to (b1-11), respectively. TIFF0007696208000053.tif23139 [In the formula (b1-9), L b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and the hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, L b19 and L b20 have a total carbon number of 23 or less. In the formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and the hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, Lb21 , L b22 and L b23 The total number of carbon atoms of is 21 or less. In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and 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 of is 21 or less. * and ** represent bonds, and * represents a bond with Y.]

[0063] In the group represented by formula (b1-9) to the group represented by formula (b1-11), when the hydrogen atom contained in the saturated hydrocarbon group is substituted with an alkylcarbonyloxy group, the number of carbon atoms before replacement is taken as the number of carbon atoms of the saturated hydrocarbon group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, an adamantylcarbonyloxy group and the like.

[0064] Examples of the group represented by formula (b1-4) include the following. TIFF0007696208000054.tif17151(* and ** represent bonds, and * represents a bond with Y.)

[0065] Examples of the group represented by formula (b1-5) include the following. TIFF0007696208000055.tif72149 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0066] Examples of the group represented by formula (b1-6) include the following. TIFF0007696208000056.tif29150 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0067] Examples of the group represented by formula (b1-7) include the following. TIFF0007696208000057.tif63151 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0068] Examples of the group represented by formula (b1-8) include the following. TIFF0007696208000058.tif23150 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0069] Examples of the group represented by formula (b1-2) include the following. TIFF0007696208000059.tif31160 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0070] Examples of the group represented by formula (b1-9) include the following. TIFF0007696208000060.tif44137 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0071] Examples of the group represented by formula (b1-10) include the following. TIFF0007696208000061.tif88159 (* and ** represent bonding hands, and * represents the bonding hand with Y.)

[0072] Examples of the group represented by formula (b1-11) include the following. TIFF0007696208000062.tif81158 (* and ** represent a linking group, and * represents a linking group with Y.)

[0073] Examples of the alicyclic hydrocarbon group represented by Y include groups represented by formula (Y1) to formula (Y11), formula (Y36) to formula (Y38). When -CH2- contained in the alicyclic hydrocarbon group represented by Y is replaced by -O-, -S(O)2- or -CO-, the number thereof may be one or two or more. Examples of such groups include groups represented by formula (Y12) to formula (Y35), formula (Y39) to formula (Y43). * represents a bond with L b1 represents a bond with TIFF0007696208000063.tif85168 The alicyclic hydrocarbon group represented by Y is preferably a group represented by any of formula (Y1) to formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39) to formula (Y43), more preferably a group represented by formula (Y11), formula (Y15), formula (Y16), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42) or formula (Y43), and even more preferably a group 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 having an oxygen atom such as formula (Y28) to formula (Y35), formula (Y39), formula (Y40), formula (Y42) or formula (Y43), the alkanediyl group between the two oxygen atoms preferably has one or more fluorine atoms. Further, among the alkanediyl groups contained in the ketal structure, the methylene group adjacent to the oxygen atom is preferably not substituted with a fluorine atom.

[0074] Examples of the substituent of the methyl group represented by Y include 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-O-R b1group or -(CH2) ja -O-CO-R b1 group (wherein, 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. ja represents any integer from 0 to 4. The -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -S(O)2- or -CO-, and the hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom.) and the like can be mentioned. As the substituent of the alicyclic hydrocarbon group represented by Y, a halogen atom, a hydroxy group, an alkyl group having 1 to 16 carbon atoms which may be substituted by a hydroxy group (the -CH2- contained in the alkyl group may be replaced by -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-O-R b1 group or -(CH2) ja -O-CO-R b1 group (wherein, 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. ja represents any integer from 0 to 4. The -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -S(O)2- or -CO-, and the hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom.) and the like can be mentioned.

[0075] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. 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, an adamantyl group, and the like. The alicyclic hydrocarbon group may have a chain hydrocarbon group, and examples thereof include a methylcyclohexyl group and a dimethylcyclohexyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 3 to 10. 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. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group. Examples of the aromatic hydrocarbon group having a chain hydrocarbon group include a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group include a p-cyclohexylphenyl group and a p-adamantylphenyl group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 14, more preferably 6 to 10. 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, and a dodecyl group. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 6, and still more preferably 1 to 4. Examples of the alkyl group substituted with a hydroxy group include hydroxyalkyl groups such as a hydroxymethyl group and a hydroxyethyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the group in which -CH2- contained in the alkyl group is replaced with -O-, -S(O)2-, -CO-, or the like include an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, or a group combining these. 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 still more preferably 1 to 4. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the combined group include a group formed by combining an alkoxy group and an alkyl group, a group formed by combining an alkoxy group and an alkoxy group, a group formed by combining an alkoxy group and an alkylcarbonyl group, and a group formed by combining an alkoxy group and an alkylcarbonyloxy group. Examples of the group formed by combining an alkoxy group and an alkyl group include an alkoxyalkyl group such as a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, and an ethoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the group formed by combining an alkoxy group and an alkoxy group include an alkoxyalkoxy group such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, and an ethoxyethoxy group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 6, and still 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, and an ethoxypropionyl group. 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, and an ethoxypropionyloxy group. 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 the groups represented by formula (Y12) to formula (Y35) and formula (Y39) to formula (Y43).

[0076] Examples of Y include the following. TIFF0007696208000064.tif160165

[0077] Y is preferably an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, more preferably an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent, even more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, and even more preferably an adamantyl group which may have a substituent, and -CH2- constituting the alicyclic hydrocarbon group or 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).

[0078] As the anion in the salt represented by formula (B1), anions represented by formula (B1-A-1) to formula (B1-A-59) [hereinafter, may be referred to as "anion (B1-A-1)" etc. according to the formula number.] are preferable, and an anion represented by any of formula (B1-A-1) to formula (B1-A-4), formula (B1-A-9), formula (B1-A-10), formula (B1-A-24) to formula (B1-A-33), formula (B1-A-36) to formula (B1-A-40), formula (B1-A-47) to formula (B1-A-59) is more preferable.

[0079] TIFF0007696208000065.tif142153

[0080] TIFF0007696208000066.tif75126

[0081] TIFF0007696208000067.tif130157

[0082] TIFF0007696208000068.tif65156

[0083] TIFF0007696208000069.tif110143

[0084] TIFF0007696208000070.tif186166Here, R i2 ~R i7 are, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, a chain hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 represent the same meaning as described above. Specific examples of the anion in the salt represented by formula (B1) include the anions described in JP-A-2010-204646.

[0085] As the anion in the salt represented by formula (B1), anions represented by formula (B1a-1) to formula (B1a-38) are preferably mentioned. TIFF0007696208000071.tif126154

[0086] TIFF0007696208000072.tif93139

[0087] TIFF0007696208000073.tif168155

[0088] Among them, anions represented by any of formula (B1a-1) to formula (B1a-3), formula (B1a-7) to formula (B1a-16), formula (B1a-18), formula (B1a-19), formula (B1a-22) to formula (B1a-38) are preferable.

[0089] Z1 + Examples of the organic cation of include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferable, and arylsulfonium cations are more preferable.

[0090] Z + Examples of the organic cation of include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferable, and arylsulfonium cations are more preferable. Specifically, cations represented by any of formula (b2-1) to formula (b2-4) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number) are mentioned.

[0091] In Formulae (b2-1) to (b2-4) of TIFF0007696208000074.tif46167, R b4 ~R b6 each independently represents a linear hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the linear hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms; the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group; and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 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 with -O-, -S-, or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, 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, the plurality of R b7 may be the same or different; and when n2 is 2 or more, the plurality of R b8 may be the same or different. R b9 and R b10 each independently represents a linear hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S-, or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, 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 -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-. R b13 ~R b18 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 any integer from 0 to 5. q2 and r2 each independently represent any integer from 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, a plurality of R b13 are the same or different, when p2 is 2 or more, a plurality of R b14 are the same or different, when q2 is 2 or more, a plurality of R b15 are the same or different, when r2 is 2 or more, a plurality of R b16 are the same or different, when s2 is 2 or more, a plurality of R b17 are the same or different, when t2 is 2 or more, a plurality of R b18 are the same or different. The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. In particular, R b9 ~R b12 The chain hydrocarbon group is preferably having 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups. TIFF0007696208000075.tif10158In particular, R b9 ~R b12 The alicyclic hydrocarbon group is preferably having 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms. Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include methylcyclohexyl group, dimethylcyclohexyl group, 2-methyladamantan-2-yl group, 2-ethyladamantan-2-yl group, 2-isopropyladamantan-2-yl group, methylnorbornyl group, isobornyl group and the like. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The alkyl fluoride group represents an alkyl group having 1 to 12 carbon atoms and having a fluorine atom, and examples thereof include fluoromethyl group, difluoromethyl group, trifluoromethyl group, perfluorobutyl and the like. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 9, more preferably 1 to 6, and still more preferably 1 to 4. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, biphenyl group, naphthyl group, and phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples thereof include an aromatic hydrocarbon group having a chain hydrocarbon group with 1 to 18 carbon atoms (such as tolyl group, xylyl group, cumenyl group, mesityl group, p-ethylphenyl group, p-tert-butylphenyl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.) and an aromatic hydrocarbon group having an alicyclic hydrocarbon group with 3 to 18 carbon atoms (such as p-cyclohexylphenyl group, p-adamantylphenyl group, etc.). When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group with 1 to 18 carbon atoms and an alicyclic hydrocarbon group with 3 to 18 carbon atoms are preferred. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include p-methoxyphenyl group. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as benzyl group, phenethyl group, phenylpropyl group, trityl group, naphthylmethyl group, and naphthylethyl group. Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group, and dodecyloxy group. Examples of the alkylcarbonyl group include acetyl group, propionyl group, and butyryl group. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, and iodine atom. Examples of the alkylcarbonyloxy group include methylcarbonyloxy group, ethylcarbonyloxy group, propylcarbonyloxy group, isopropylcarbonyloxy group, butylcarbonyloxy group, sec-butylcarbonyloxy group, tert-butylcarbonyloxy group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyloxy group, and 2-ethylhexylcarbonyloxy group. R b4 and R b5The ring formed by the combination of them together with the sulfur atom to which they are attached may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. Further, the ring containing a sulfur atom includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings, and examples thereof include the following rings. * represents a bond. TIFF0007696208000076.tif23143R b9 and R b10 The ring formed by their combination may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. For example, thiolan-1-ium ring (tetrahydrothiophenium ring), thian-1-ium ring, 1,4-oxathian-4-ium ring and the like can be mentioned. R b11 and R b12 The ring formed by their combination may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring and the like.

[0092] Among cations (b2-1) to (b2-4), preferably, it is cation (b2-1). Examples of cation (b2-1) include the following cations. TIFF0007696208000077.tif117169

[0093] TIFF0007696208000078.tif72165

[0094] Examples of cation (b2-2) include the following cations. TIFF0007696208000079.tif18150

[0095] Examples of the cation (b2-3) include the following cations. TIFF0007696208000080.tif26140

[0096] Examples of the cation (b2-4) include the following cations. TIFF0007696208000081.tif62166

[0097] TIFF0007696208000082.tif69157 The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. As the acid generator (B), preferably, an anion represented by any of the formulas (B1a-1) to (B1a-3), (B1a-7) to (B1a-16), (B1a-18), (B1a-19), (B1a-22) to (B1a-38) and a combination with the cation (b2-1), the cation (b2-3) or the cation (b2-4) are mentioned.

[0098] As the acid generator (B), preferably, those represented by the formulas (B1-1) to (B1-56) are mentioned. Among them, those containing an arylsulfonium cation are preferable, and those represented by the formulas (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-56) are particularly preferable. TIFF0007696208000083.tif62150

[0099] TIFF0007696208000084.tif131164

[0100] TIFF0007696208000085.tif87150

[0101] TIFF0007696208000086.tif163153

[0102] TIFF0007696208000087.tif76141

[0103] TIFF0007696208000088.tif158158

[0104] When containing salt (I) and acid generator (B) as the acid generator, the ratio of the contents of salt (I) and acid generator (B) (mass ratio; salt (I): acid generator (B)) is usually 1:99 to 99:1, preferably 2:98 to 98:2, more preferably 5:95 to 95:5, still more preferably 10:90 to 90:10, and particularly preferably 15:85 to 85:15. In the resist composition of the present invention, the total content rate of the acid generator is preferably 1 part by mass or more and 45 parts by mass or less, more preferably 3 parts by mass or more and 40 parts by mass or less, based on 100 parts by mass of the resin (A) described later.

[0105] <Resist composition> The resist composition of the present invention contains an acid generator containing salt (I) and a resin having an acid-labile group (hereinafter sometimes referred to as "resin (A)"). Here, the "acid-labile group" means a group having a leaving group, and when contacted with an acid, the leaving group leaves and the constitutional unit is converted into a constitutional unit having a hydrophilic group (for example, a hydroxy group or a carboxy group). The resist composition of the present invention preferably contains a quencher (hereinafter sometimes referred to as "quencher (C)") such as a salt that generates an acid having a lower acidity than the acid generated from the acid generator, and preferably contains a solvent (hereinafter sometimes referred to as "solvent (E)").

[0106] <Resin (A)> Resin (A) has a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)"). Resin (A) preferably further contains a structural unit other than structural unit (a1). Examples of the structural unit other than structural unit (a1) include a structural unit having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)"), a structural unit other than structural unit (a1) and structural unit (s) (for example, a structural unit having a halogen atom described later (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group described later (hereinafter sometimes referred to as "structural unit (a5)"), and structural units derived from other monomers known in the art, etc.).

[0107] 〈Structural unit (a1)〉 Structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid-labile group contained in resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF0007696208000089.tif2298[In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, or R a1 and R a2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bond. ] TIFF0007696208000090.tif2278[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’They are bonded to each other to form, together with the carbon atoms to which they are bonded and X, a heterocyclic group having 3 to 20 carbon atoms, and the —CH2— contained in the hydrocarbon group and the heterocyclic group may be replaced by —O— or —S—. X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bond.]

[0108] R a1 、R a2 and R a3 Examples of the alkyl group for R R a1 、R a2 and R a3 include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group and the like. Examples of the alkenyl group for R R a1 、R a2 and R a3 include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octynyl group, isooctynyl group, nonenyl group. The alicyclic hydrocarbon group for R a1 、R a2 and R a3 may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents a bond). The number of carbon atoms of the alicyclic hydrocarbon group for R TIFF0007696208000091.tif10159R a1 、R a2 and R a3 include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, etc. Preferably, ma is 0 and na is 1. R a1 and R a2 When they are bonded to each other to form an alicyclic hydrocarbon group, examples of -C(R a1 )(R a2 )(R a3 ) include the following groups. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents a bond to -O-. TIFF0007696208000092.tif35158

[0109] R a1’ 、R a2’ and R a3’ Examples of the hydrocarbon group in R The alkyl group and alicyclic hydrocarbon group include the same groups as those exemplified for R a1 、R a2 and R a3 . Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group, etc. Examples of the combined group include a group combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, and the like. R a2’ and R a3’ When R and R are bonded to each other to form a heterocyclic ring together with the carbon atom to which they are bonded and X, -C(R a1' )(R a2' )-X-R a3' includes the following groups. * represents a bond. TIFF0007696208000093.tif18124R a1’ and R a2’ Among them, at least one is preferably a hydrogen atom. na’ is preferably 0.

[0110] Examples of group (1) include the following groups. In formula (1), a group in which R a1 , R a2 and R a3 are alkyl groups, ma = 0, and na = 1. As such a group, a tert-butoxycarbonyl group is preferable. In formula (1), R a1 , R a2 together with the carbon atom to which they are bonded form an adamantyl group, R a3 is an alkyl group, ma = 0, and na = 1. In formula (1), R a1 and R a2are each independently an alkyl group, R a3 is an adamantyl group, a group where ma = 0 and na = 1. Specific examples of the group (1) include the following groups. * represents a bond. TIFF0007696208000094.tif170163

[0111] Specific examples of the group (2) include the following groups. * represents a bond. TIFF0007696208000095.tif68162

[0112] 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.

[0113] Among the (meth)acrylic monomers having an acid-labile group, preferably those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms can be mentioned. If a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0114] As the structural unit derived from the (meth)acrylic monomer having the group (1), preferably, the structural unit represented by the formula (a1-0) (hereinafter, may be referred to as the structural unit (a1-0)), the structural unit represented by the formula (a1-1) (hereinafter, may be referred to as the structural unit (a1-1)), or the structural unit represented by the formula (a1-2) (hereinafter, may be referred to as the structural unit (a1-2)) can be mentioned. More preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF0007696208000096.tif46149[In the formula (a1-0), the formula (a1-1), and the formula (a1-2), L a01 、L a1 and L a2Each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents an integer from 1 to 7, and * represents a bond to -CO-. R a01 R a4 and R a5 represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 R a03 and R a04 each independently represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these. R a6 and R a7 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these. m1 represents an integer from 0 to 14. n1 represents an integer from 0 to 10. n1’ represents an integer from 0 to 3.]

[0115] R a01 R a4 and R a5 are preferably a hydrogen atom or a methyl group, and more preferably a methyl group. L a01 L a1 and L a2 are preferably an oxygen atom or *-O-(CH2) k01 -CO-O- (where k01 is preferably an integer from 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 R a03 R a04 R a6 and R a7 As the alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and the group formed by combining these in R a1 R a2and R a3 include groups similar to the groups listed above. R a02 、R a03 、and R a04 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and still more preferably a methyl group. R a6 and R a7 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group or a t-butyl group, and still more preferably an ethyl group, an isopropyl group or a t-butyl group. R a6 and R a7 The alkenyl group in is preferably an alkenyl group having 2 to 6 carbon atoms, more preferably an ethenyl group, a propenyl group, an isopropenyl group or a butenyl group. R a02 、R a03 、R a04 、R a6 and R a7 The number of carbon atoms of the alicyclic hydrocarbon group of is preferably 5 to 12, more preferably 5 to 10. R a02 、R a03 、R a04 、R a6 and R a7 The number of carbon atoms of the aromatic hydrocarbon group of is preferably 6 to 12, more preferably 6 to 10. The group formed by combining an alkyl group and an alicyclic hydrocarbon group preferably has a total number of carbon atoms of 18 or less when these alkyl group and alicyclic hydrocarbon group are combined. The group formed by combining an alkyl group and an aromatic hydrocarbon group preferably has a total number of carbon atoms of 18 or less when these alkyl group and aromatic hydrocarbon group are combined. R a02 and R a03 are preferably an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group. R a04is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, a phenyl group or a naphthyl group, and even more preferably an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group or a phenyl group. m1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1’ is preferably 0 or 1.

[0116] Examples of the structural unit (a1-0) include structural units represented by any of the formulas (a1-0-1) to (a1-0-18) and structural units in which the methyl group corresponding to R a01 in the structural unit (a1-0) is replaced by a hydrogen atom. Structural units represented by any of the formulas (a1-0-1) to (a1-0-10), (a1-0-13), and (a1-0-14) are preferred. TIFF0007696208000097.tif100167

[0117] Examples of the structural unit (a1-1) include structural units derived from the monomers described in JP-A-2010-204646. Among them, structural units represented by any of the formulas (a1-1-1) to (a1-1-7) and structural units in which the methyl group corresponding to R a4 in the structural unit (a1-1) is replaced by a hydrogen atom are preferred, and structural units represented by any of the formulas (a1-1-1) to (a1-1-4) are more preferred. TIFF0007696208000098.tif39156

[0118] Examples of the structural unit (a1-2) include a structural unit represented by any one of formula (a1-2-1) to formula (a1-2-12) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced by a hydrogen atom. Among them, a structural unit represented by any one of formula (a1-2-2), formula (a1-2-5), formula (a1-2-6), and formula (a1-2-10) to formula (a1-2-12) is preferable. a5 When the resin (A) contains the structural unit (a1-0), its content is usually 5 to 60 mol%, preferably 5 to 50 mol%, more preferably 10 to 40 mol%, based on all the structural units of the resin (A). TIFF0007696208000099.tif75156

[0119] When the resin (A) contains the structural unit (a1-0), its content is usually 5 to 60 mol%, preferably 5 to 50 mol%, more preferably 10 to 40 mol%, based on all the structural units of 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 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%, based on all the structural units of the resin (A).

[0120] Examples of the structural unit having the group (2) in the structural unit (a1) include a structural unit represented by formula (a1-4) (hereinafter sometimes referred to as "structural unit (a1-4)"). TIFF0007696208000100.tif3954[In formula (a1-4), R a32 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a33 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a30 represents a single bond or * -X a31-(A a32 -X a32 ) nc - represents, and * represents the bonding site with the carbon atom to which -R a32 is bonded. A a32 represents an alkanediyl group having 1 to 6 carbon atoms. X a31 and X a32 each independently represent -O-, -CO-O- or -O-CO-. nc represents 0 or 1. la represents any integer from 0 to 4. When la is any integer of 2 or more, a plurality of R a33 may be the same as or different from each other. R a34 and R a35 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-.

[0121] R a32 and R a33 Examples of the halogen atom in R include a fluorine atom, a chlorine atom, and a bromine atom. R a32 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, and a perfluorohexyl group. R a32is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a33 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a33 Examples of the alkoxy group in include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a33 Examples of the alkoxyalkyl group in include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a33 Examples of the alkoxyalkoxy group in include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethyl group or an ethoxyethyl group. R a33 Examples of the alkylcarbonyl group in include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a33Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a33 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0122] *-X a31 -(A a32 -X a32 ) nc Examples of - include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a32 -CO-O-, *-O-CO-A a32 -O-, *-O-A a32 -CO-O-, *-CO-O-A a32 -O-CO-, *-O-CO-A a32 -O-CO- are included. Among them, *-CO-O-, *-CO-O-A a32 -CO-O- or *-O-A a32 -CO-O- is preferred.

[0123] Examples of the alkanediyl group include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A a32 is preferably a methylene group or an ethylene group.

[0124] A a30is a single bond, *-CO-O- or *-CO-O-A a32 -CO-O- is preferred, more preferably a single bond, *-CO-O- or *-CO-O-CH2-CO-O-, and even more preferably a single bond or *-CO-O-.

[0125] la is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. R a34 、R a35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group and the like. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group and the following groups (* represents a bonding site). TIFF0007696208000101.tif10151 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a phenanthryl group and the like. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, etc. In particular, R a36 Examples of R include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these.

[0126] R a34 is preferably a hydrogen atom. R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a36 The hydrocarbon group of R is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic aliphatic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. The alkyl group and the alicyclic hydrocarbon group in R a36 are preferably unsubstituted. The aromatic hydrocarbon group in R a36 preferably has an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0127] -OC(R a34 )(R a35 )-O-R in the structural unit (a1-4)a36 Upon contact with an acid (e.g., p-toluenesulfonic acid), it dissociates to form a hydroxy group. -OC(R a34 )(R a35 )-O-R a36 Preferably binds to the o-position or p-position of the benzene ring, more preferably binds to the p-position.

[0128] Examples of the structural unit (a1-4) include structural units derived from the monomers described in JP-A-2010-204646. Preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-18) and the hydrogen atom corresponding to R in the structural unit (a1-4) replaced by a methyl group are mentioned, 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) are mentioned. a32 When the resin (A) has the structural unit (a1-4), its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, still more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol% based on the total of all the structural units of the resin (A). TIFF0007696208000102.tif100166

[0129] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) also include the structural unit represented by formula (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)").

[0130] In formula (a1-5), TIFF0007696208000103.tif4253 R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. Z a1 represents a single bond or *-(CH2) h3 -CO-L 54represents -, h3 represents any integer from 1 to 4, and * represents a bond with L 51 represents a bond with L L 51 L 52 L 53 and L 54 each independently represents -O- or -S-. s1 represents any integer from 1 to 3. s1’ represents any integer from 0 to 3.

[0131] Examples of the halogen atom include a fluorine atom and a chlorine atom, and a fluorine atom is preferred. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a fluoromethyl group, and a trifluoromethyl group. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Among them, it is preferred that one is -O- and the other is -S-. s1 is preferably 1. s1’ is preferably any integer from 0 to 2. Z a1 is preferably a single bond or *-CH2-CO-O-.

[0132] Examples of the structural unit (a1-5) include, for example, a structural unit derived from a monomer described in JP-A-2010-61117. Among them, the structural units represented by formula (a1-5-1) to formula (a1-5-4) are preferred, and the structural unit represented by formula (a1-5-1) or formula (a1-5-2) is more preferred. TIFF0007696208000104.tif31129

[0133] When the resin (A) has the structural unit (a1-5), its content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, still more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol% based on all the structural units of the resin (A).

[0134] Examples of the structural unit (a1) also include the following structural units. TIFF0007696208000105.tif27161

[0135] When the resin (A) contains structural units such as (a1-3-1) to (a1-3-7) above, its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol% based on all the structural units of the resin (A).

[0136] 〈Structural unit (s)〉 The structural unit (s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer (s)"). As the monomer that leads to the structural unit (s), a monomer having no acid-labile group known in the resist field can be used. The structural unit (s) preferably has a hydroxy group or a lactone ring. By using a resin having a structural unit having a hydroxy group and no acid-labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and no acid-labile group (hereinafter sometimes referred to as "structural unit (a3)") in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved.

[0137] 〈Structural unit (a2)〉 The hydroxy group of 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, when using a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) as an exposure light source, as the structural unit (a2), a structural unit (a2) having a phenolic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-A) described later. Further, when using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-1) described later. As the structural unit (a2), one kind may be contained alone, or two or more kinds may be contained.

[0138] Examples of the structural unit having a phenolic hydroxy group in the structural unit (a2) include a structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF0007696208000106.tif4551[In the 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 represents a single bond or *-X a51 -(A a52 -X a52 ) nb -, and * represents a bond with the carbon atom to which -R a50 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 from 0 to 4. When mb is an integer of 2 or more, a plurality of Rs a51 may be the same as or different from each other.]

[0139] R a50 and R a51 Examples of the halogen atom in R include a fluorine atom, a chlorine atom, and a bromine atom, etc. R a50 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, and a perfluorohexyl group. R a50 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 a51 Examples of the alkyl group in R include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a51 Examples of the alkoxy group in R include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The alkoxy group is preferably 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 a51Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a51 Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. R a51 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a51 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a51 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0140] *-X a51 -(A a52 -X a52 ) nb- includes, among others, *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a52 -CO-O-, *-O-CO-A a52 -O-, *-O-A a52 -CO-O-, *-CO-O-A a52 -O-CO-, *-O-CO-A a52 -O-CO- is included. Among them, *-CO-O-, *-CO-O-A a52 -CO-O- or *-O-A a52 -CO-O- is preferred.

[0141] Examples of the alkanediyl group include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A a52 is preferably a methylene group or an ethylene group.

[0142] A a50 is preferably a single bond, *-CO-O- or *-CO-O-A a52 -CO-O-, more preferably a single bond, *-CO-O- or *-CO-O-CH2-CO-O-, and even more preferably a single bond or *-CO-O-.

[0143] 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 position or the para position of the benzene ring, and more preferably bonded to the para position.

[0144] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-16) and structural units in which the methyl group corresponding to R in the structural unit (a2-A) in the structural units represented by Formula (a2-2-1) to Formula (a2-2-16) is replaced with a hydrogen atom. The structural unit (a2-A) is preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-3) or the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, and even more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-8) and the structural unit represented by Formula (a2-2-8) is replaced with a hydrogen atom. a50 Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-16) and structural units in which the methyl group corresponding to R in the structural unit (a2-A) in the structural units represented by Formula (a2-2-1) to Formula (a2-2-16) is replaced with a hydrogen atom. The structural unit (a2-A) is preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-3) or the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, and even more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-8) and the structural unit represented by Formula (a2-2-8) is replaced with a hydrogen atom. a50 Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-16) and structural units in which the methyl group corresponding to R in the structural unit (a2-A) in the structural units represented by Formula (a2-2-1) to Formula (a2-2-16) is replaced with a hydrogen atom. The structural unit (a2-A) is preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-3) or the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, and even more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-8) and the structural unit represented by Formula (a2-2-8) is replaced with a hydrogen atom. a50 Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-16) and structural units in which the methyl group corresponding to R in the structural unit (a2-A) in the structural units represented by Formula (a2-2-1) to Formula (a2-2-16) is replaced with a hydrogen atom. The structural unit (a2-A) is preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-3) or the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, and even more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-8) and the structural unit represented by Formula (a2-2-8) is replaced with a hydrogen atom. a50 Examples of the structural unit (a2-A) include structural units represented by Formula (a2-2-1) to Formula (a2-2-16) and structural units in which the methyl group corresponding to R in the structural unit (a2-A) in the structural units represented by Formula (a2-2-1) to Formula (a2-2-16) is replaced with a hydrogen atom. The structural unit (a2-A) is preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-1), the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-6), the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-3), the structural unit represented by Formula (a2-2-8), the structural units represented by Formula (a2-2-12) to Formula (a2-2-14), and the structural unit represented by Formula (a2-2-3) or the structural unit represented by Formula (a2-2-8), and the structural units represented by Formula (a2-2-12) to Formula (a2-2-14) is replaced with a hydrogen atom, and even more preferably a structural unit in which the methyl group corresponding to R in the structural unit (a2-A) in the structural unit represented by Formula (a2-2-8) and the structural unit represented by Formula (a2-2-8) is replaced with a hydrogen atom. TIFF0007696208000107.tif64170

[0145] When the resin (A) contains the structural unit (a2-A), the content of the structural unit (a2-A) is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, still more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol% based on all the structural units. The structural unit (a2-A) can be incorporated into the resin (A) by, for example, polymerizing using the structural unit (a1-4) and then treating with an acid such as p-toluenesulfonic acid. Also, after polymerizing using acetoxystyrene or the like, the structural unit (a2-A) can be incorporated into the resin (A) by treating with an alkali such as tetramethylammonium hydroxide.

[0146] Examples of the structural unit having an alcoholic hydroxy group in the structural unit (a2) include a structural unit represented by the formula (a2-1) (hereinafter sometimes referred to as "structural unit (a2-1)"). TIFF0007696208000108.tif4157In the formula (a2-1), L a3 represents -O- or *-O-(CH2) k2 -CO-O-, k2 represents an integer of any one of 1 to 7. * represents a bond with -CO-. R a14 represents a hydrogen atom or a methyl group. R a15 and R a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group. o1 represents an integer of any one of 0 to 10.

[0147] In the formula (a2-1), L a3 is preferably -O-, -O-(CH2) f1 -CO-O- (wherein f1 represents an integer of any one of 1 to 4), more preferably -O-. R a14 is preferably a methyl group. R a15 is preferably a hydrogen atom. R a16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of any one of 0 to 3, more preferably 0 or 1.

[0148] Examples of the structural unit (a2-1) include structural units derived from the monomers described in JP-A-2010-204646. The structural unit represented by any of formula (a2-1-1) to formula (a2-1-6) is preferable, the structural unit represented by any of formula (a2-1-1) to formula (a2-1-4) is more preferable, and the structural unit represented by formula (a2-1-1) or formula (a2-1-3) is even more preferable. TIFF0007696208000109.tif54150

[0149] 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 even more preferably 1 to 10 mol% based on all the structural units of the resin (A).

[0150] 〈Structural unit (a3)〉 The lactone ring of the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)) can be mentioned.

[0151] The structural unit (a3) is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3), or formula (a3-4). These may be contained alone or in combination of two or more. TIFF0007696208000110.tif52167[In formula (a3-1), formula (a3-2), formula (a3-3), and formula (a3-4), L a4 , L a5 and L a6 each independently represents a group represented by -O- or *-O-(CH2) k3 -CO-O- (where k3 represents an integer of 1 to 7). L a7 is -O-, *-O-La8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding site with the carbonyl group. R a18 R a19 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 a halogen atom, a hydrogen atom or a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 R a23 and R a25 each independently represents a carboxy group, a cyano group or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents any integer from 0 to 5. q1 represents any integer from 0 to 3. r1 represents any integer from 0 to 3. w1 represents any integer from 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, the plurality of R a21 R a22 R a23 and / or R a25 may be the same as or different from each other.

[0152] R a21 R a22 R a23 and R a25Examples of the aliphatic hydrocarbon group in [description] include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, and tert-butyl group. R a24 Examples of the halogen atom in [description] include fluorine atom, chlorine atom, bromine atom, and iodine atom. R a24 Examples of the alkyl group in [description] include methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl group, etc. Preferably, alkyl groups having 1 to 4 carbon atoms are included, and more preferably, methyl group or ethyl group is included. R a24 Examples of the alkyl group having a halogen atom in [description] include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group, perfluorohexyl group, trichloromethyl group, tribromomethyl group, triiodomethyl group, etc. L a8 and L a9 Examples of the alkanediyl group in [description] and [description] include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group, etc.

[0153] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently, preferably -O- or, *-O-(CH2) k3 -CO-O- in which k3 is an integer of any one 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 are each independently preferably an integer of any one of 0 to 2, more preferably 0 or 1.

[0154] 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, still 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 *-O-L a8 -CO-O-, more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. w1 is preferably an integer of any one of 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)'. TIFF0007696208000111.tif4051 (wherein R a24 , L a7 represent the same meaning as described above.)

[0155] Examples of the structural unit (a3) include structural units derived from the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. Examples of the structural unit (a3) include structural units represented by any of formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2), formula (a3-3-1), formula (a3-3-2) and formula (a3-4-1) to formula (a3-4-12), and in the above structural units, R a18 , R a19 , R a20 and R a24A structural unit in which the methyl group corresponding thereto is replaced by a hydrogen atom is preferred.

[0156] TIFF0007696208000112.tif115165

[0157] When the resin (A) contains the structural unit (a3), the total content thereof is usually 5 to 70 mol%, preferably 10 to 65 mol%, more preferably 10 to 60 mol% with respect to all the structural units of the resin (A). Also, 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 5 to 60 mol%, more preferably 5 to 50 mol%, still more preferably 10 to 50 mol% with respect to all the structural units of the resin (A).

[0158] 〈Structural unit (a4)〉 Examples of the structural unit (a4) include the following structural units. TIFF0007696208000113.tif3066[In the formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having a fluorine atom with 1 to 24 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO.] R 42 Examples of the saturated hydrocarbon group represented by include a chain hydrocarbon group, a monocyclic or polycyclic alicyclic hydrocarbon group, and a group formed by combining these.

[0159] Examples of the chain hydrocarbon group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, hexadecyl group, heptadecyl group, and octadecyl group. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooctyl group; and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl group, adamantyl group, norbornyl group, and the following group (* represents a bond). Examples of the group formed by the combination of 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, -alkanediyl group-alicyclic hydrocarbon group-alkyl group, and the like.

[0160] Examples of the structural unit (a4) include structural units represented by at least one selected from the group consisting of formula (a4-0), formula (a4-1), formula (a4-2), formula (a4-3), and formula (a4-4). TIFF0007696208000115.tif4652[In formula (a4-0), R 5 represents a hydrogen atom or a methyl group. L 4a represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 4 carbon atoms. L 3a represents a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms. R 6 represents a hydrogen atom or a fluorine atom.]

[0161] L 4aExamples of the divalent aliphatic saturated hydrocarbon group in [substance name] include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, and butane-1,4-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, and 2-methylpropane-1,2-diyl group. L 3a Examples of the perfluoroalkanediyl group in [substance name] include difluoromethylene group, perfluoroethylene group, perfluoropropane-1,1-diyl 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-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, perfluorooctane-4,4-diyl group, etc. L 3a Examples of the perfluorocycloalkanediyl group in [substance name] include perfluorocyclohexanediyl group, perfluorocyclopentanediyl group, perfluorocycloheptanediyl group, perfluoroadamantanediyl group, etc.

[0162] L 4a is preferably a single bond, a methylene group or an ethylene group, more preferably a single bond or a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0163] As the structural unit (a4-0), there are the following structural units and the structural units in the following structural units where the methyl group corresponding to R in the structural unit (a4-0) is replaced by a hydrogen atom. 5 Examples thereof include structural units in which the methyl group corresponding to R is replaced by a hydrogen atom. TIFF0007696208000116.tif95165

[0164] TIFF0007696208000117.tif4466[In formula (a4-1), R a41 represents a hydrogen atom or a methyl group. R a42 represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. A a41 represents an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a group represented by formula (a-g1). However, at least one of a41 A a42 and R has a halogen atom (preferably a fluorine atom) as a substituent. TIFF0007696208000118.tif1384[In formula (a-g1), s represents 0 or 1. A a42 and A a44 each independently represent a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. A a43 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. X a41 and X a42 each independently represent -O-, -CO-, -CO-O- or -O-CO-. However, the total number of carbon atoms of a42 A a43 A a44 X a41 and X a42 is 7 or less. ] * represents a bond, and the * on the right side is -O-CO-Ra42 is a bonding hand with it.]

[0165] R a42 Examples of the saturated hydrocarbon group in R include a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these. 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 hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; polycyclic alicyclic saturated hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bonding hand). Examples of the group formed by combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, such as -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group, etc.

[0166] R a42 Examples of the substituent that R may have include at least one selected from a halogen atom and a group represented by the formula (a-g3). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and preferably a fluorine atom. TIFF0007696208000120.tif965[In the formula (a-g3), X a43 represents an oxygen atom, a carbonyl group, *-O-CO- or *-CO-O-. A a45 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. * is the bonding hand with R a42 and represents the bonding hand with it.] However, Ra42 -X a43 -A a45 In, when R a42 has no halogen atom, A a45 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms and at least one halogen atom.

[0167] A a45 Examples of the aliphatic hydrocarbon group in A include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, hexadecyl group, heptadecyl group, and octadecyl group; monocyclic alicyclic hydrocarbon groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooctyl group; and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl group, adamantyl group, norbornyl group, and the following group (* represents a bond). Examples of the group formed by the combination of TIFF0007696208000121.tif11159 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, -alkanediyl group-alicyclic hydrocarbon group-alkyl group, etc.

[0168] R a42 is preferably an aliphatic hydrocarbon group which may have a halogen atom, more preferably an alkyl group having a halogen atom and / or an aliphatic hydrocarbon group having a group represented by the formula (a-g3). R a42When it is an aliphatic hydrocarbon group having a halogen atom, it is preferably an aliphatic hydrocarbon group having a fluorine atom, more preferably a perfluoroalkyl group or a perfluorocycloalkyl group, still more preferably a perfluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably a perfluoroalkyl group having 1 to 3 carbon atoms. Examples of the perfluoroalkyl group 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 the perfluorocycloalkyl group include a perfluorocyclohexyl group. R a42 When it is an aliphatic hydrocarbon group having a group represented by the formula (a-g3), including the number of carbon atoms contained in the group represented by the formula (a-g3), R a42 Preferably has a total carbon number of 15 or less, more preferably 12 or less. When having a group represented by the formula (a-g3) as a substituent, the number thereof is preferably 1.

[0169] R a42 When it is an aliphatic hydrocarbon having a group represented by the formula (a-g3), R a42 Is more preferably a group represented by the formula (a-g2). TIFF0007696208000122.tif879 [In the formula (a-g2), A a46 Represents a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. X a44 Represents -O-CO- or -CO-O- (** represents a bond with A a46 Represents a bond). A a47 Represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. However, A a46 、A a47 And X a44 The total number of carbon atoms of is 18 or less, and A a46 And A a47 At least one of them has at least one halogen atom. * represents a bond to a carbonyl group.

[0170] A a46 The number of carbon atoms in the aliphatic hydrocarbon group of A is preferably from 1 to 6, more preferably from 1 to 3. A a47 The number of carbon atoms in the aliphatic hydrocarbon group of A is preferably from 4 to 15, more preferably from 5 to 12, and A a47 is more preferably a cyclohexyl group or an adamantyl group.

[0171] The preferred structure of the group represented by formula (a-g2) is the following structure (* is a bond to a carbonyl group). TIFF0007696208000123.tif13161

[0172] A a41 Examples of the alkanediyl group in A include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group; 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, 2-methylbutane-1,4-diyl group. A a41 Examples of the substituent in the alkanediyl group of A include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms. A a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably an alkanediyl group having 2 to 4 carbon atoms, and still more preferably an ethylene group.

[0173] A in the group represented by formula (a-g1) a42 、A a43 and A a44Examples of the divalent saturated hydrocarbon group represented by include a linear or branched alkanediyl group, a monocyclic divalent alicyclic hydrocarbon group, and a group formed by combining an alkanediyl group and a divalent alicyclic 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, a 2-methylpropane-1,2-diyl group, etc. A a42 , A a43 and A a44 Examples of the substituent of the divalent saturated hydrocarbon group represented by the formula (1) include a hydroxy group and an alkoxy group having 1 to 6 carbon atoms. It is preferred that s is 0.

[0174] In the group represented by formula (a-g1), X a42 In the following examples, * and ** each represent a bond, and ** represents -O-CO-R a42 It is a combination with. TIFF0007696208000124.tif54162

[0175] 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 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF0007696208000125.tif47144

[0176] TIFF0007696208000126.tif186147

[0177] The structural unit represented by formula (a4-1) is preferably a structural unit represented by formula (a4-2). TIFF0007696208000127.tif4365[In formula (a4-2), R f5represents a hydrogen atom or a methyl group. L 44 represents an alkanediyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. R f6 represents a saturated hydrocarbon group having 1 to 20 carbon atoms and having a fluorine atom. However, the upper limit of the total carbon number of 44 L f6 and

[0178] L 44 The alkanediyl group having 1 to 6 carbon atoms is the same as the group exemplified as the alkanediyl group in a41 A. R f6 The saturated hydrocarbon group of a42 is the same as the group exemplified by L 44 As the alkanediyl group having 1 to 6 carbon atoms in

[0179] As the structural unit represented by the formula (a4-2), for example, the structural units represented by the formulas (a4-1-1) to (a4-1-11) can be mentioned. The structural unit in which the methyl group corresponding to f5 R in the structural unit (a4-2) is replaced by a hydrogen atom is also mentioned as the structural unit represented by the formula (a4-2).

[0180] As the structural unit (a4), the structural unit represented by the formula (a4-3) can be mentioned. TIFF0007696208000128.tif5771[In the 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. X f12represents *-O-CO- or *-CO-O- (* represents a bond with A f13 .). A f14 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, at least one of A f13 and A f14 has a fluorine atom, and the upper limit of the total number of carbon atoms of L 5 , A f13 and A f14 is 20.]

[0181] L 5 Examples of the alkanediyl group in include the same groups as those exemplified for the alkanediyl group in the divalent saturated hydrocarbon group of A a41 . A f13 Examples of the divalent saturated hydrocarbon group which may have a fluorine atom in include preferably a divalent aliphatic 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 aliphatic 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; perfluoroalkanediyl groups such as a difluoromethylene group, a perfluoroethylene group, a perfluoropropanediyl group, a perfluorobutanediyl group and a perfluoropentanediyl group. The divalent alicyclic hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include a cyclohexanediyl group and a perfluorocyclohexanediyl group. Examples of the polycyclic group include an adamantanediyl group, a norbornanediyl group and a perfluoroadamantanediyl group. A f14 The saturated hydrocarbon group and the saturated hydrocarbon group which may have a fluorine atom of are R a42Groups similar to those exemplified above can be mentioned. Among them, a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group, a perfluorooctyl group and other alkyl fluoride groups, a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, an adamantyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, a perfluoroadamantylmethyl group and the like are preferable.

[0182] In formula (a4-3), L 5 is preferably an ethylene group. A f13 The divalent saturated hydrocarbon group of is preferably a group containing a divalent chain hydrocarbon group having 1 to 6 carbon atoms and a divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a divalent chain hydrocarbon group having 2 to 3 carbon atoms. A f14 The saturated hydrocarbon group of is preferably a group containing a chain hydrocarbon group having 3 to 12 carbon atoms and an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a group containing a chain hydrocarbon group having 3 to 10 carbon atoms and an alicyclic hydrocarbon group having 3 to 10 carbon atoms. Among them, A f14 is preferably a group containing an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group and an adamantyl group.

[0183] Examples of the structural unit represented by formula (a4-3) include structural units represented by formulas (a4-1'-1) to (a4-1'-11), respectively. R in structural unit (a4-3)f7 A structural unit in which the methyl group corresponding to f7 is replaced by a hydrogen atom can also be cited as a structural unit represented by formula (a4-3).

[0184] Examples of the structural unit (a4) also include a structural unit represented by formula (a4-4). TIFF0007696208000129.tif4466[In formula (a4-4), R f21 represents a hydrogen atom or a methyl group. A f21 represents -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 - or -(CH2) j4 -CO-O-(CH2) j5 -. 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 having a fluorine atom.]

[0185] R f22 The saturated hydrocarbon group of is the same as the saturated hydrocarbon group represented by R a42 . R f22 is preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom or an alicyclic hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0186] In formula (a4-4), A f21 is preferably -(CH2) j1 -, more preferably an ethylene group or a methylene group, and even more preferably a methylene group.

[0187] Examples of the structural unit represented by formula (a4-4) include, for example, the following structural units and the structural units represented by the following formulas, in which the methyl group corresponding to R f21 in the structural unit (a4-4) is replaced by a hydrogen atom. TIFF0007696208000130.tif80148

[0188] When the resin (A) has the structural unit (a4), its content is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and still more preferably 3 to 10 mol% based on all the structural units of the resin (A).

[0189] 〈Structural unit (a5)〉 Examples of the non-detachable hydrocarbon group contained in the structural unit (a5) include groups having a linear, branched or cyclic hydrocarbon group. Among them, the structural unit (a5) preferably has a group having an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by the formula (a5-1). TIFF0007696208000131.tif3971[In the formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with aliphatic hydrocarbon groups having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0190] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group etc. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group and a 2-ethylhexyl group etc. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group. L 55 Examples of the divalent saturated hydrocarbon group in L include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, preferably a divalent chain saturated hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include alkane diyl groups such as a methylene group, an ethylene group, a 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 cycloalkane diyl groups such as a cyclopentanediyl group and a cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include an adamantanediyl group and a norbornanediyl group.

[0191] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO- include the groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** each represent a bond, and * represents a bond to an oxygen atom. In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents a bond to L x1 .). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the total number of carbon atoms of L x1 and L x2 is 16 or less. In formula (L1-2), Lx3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the total number of carbon atoms in L x3 and L x4 is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms in L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, the total number of carbon atoms in L x8 , L x9 and W x1 is 15 or less.

[0192] 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 x5is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0193] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF0007696208000133.tif23135

[0194] TIFF0007696208000134.tif33116

[0195] Examples of the group represented by the formula (L1-2) include the following divalent groups. TIFF0007696208000135.tif23130

[0196] Examples of the group represented by the formula (L1-3) include the following divalent groups. TIFF0007696208000136.tif15144

[0197] Examples of the group represented by the formula (L1-4) include the following divalent groups. TIFF0007696208000137.tif26114

[0198] L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0199] As the structural unit (a5-1), there may be mentioned the following structural units and the structural units in the following structural units where the methyl group corresponding to R 51 in the structural unit (a5-1) is replaced by a hydrogen atom. TIFF0007696208000138.tif75150

[0200] When the resin (A) has the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and still more preferably 3 to 15 mol% based on all the structural units of the resin (A).

[0201] <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 preferably a structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain or a structural unit having a sulfonio group and an organic anion in the side chain.

[0202] The structural unit having a sulfonate group or a carboxylate group in the side chain is preferably a structural unit represented by the formula (II-2-A'). TIFF0007696208000140.tif35104[In the formula (II-2-A'), X III3represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, wherein -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 by 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.

[0203] R III3 Examples of the halogen atom represented by R include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. R III3 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R include the same as those of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R a8 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R include the same as those of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R. A x1 Examples of the alkanediyl group having 1 to 8 carbon atoms represented by A 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, a 2-methylbutane-1,4-diyl group and the like. A X1Examples of the optionally substituted C1-C6 perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, and the like. X III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by III3 include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and combinations thereof may also be acceptable. Specifically, linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group; branched alkanediyl groups such as a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, a 2-methylbutane-1,4-diyl group; cycloalkanediyl groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclooctane-1,5-diyl group; and divalent polycyclic alicyclic saturated hydrocarbon groups such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, etc. are included. Examples of those in which -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- include divalent groups represented by formula (X1) to formula (X53). However, the carbon number before -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- is 17 or less, respectively. In the following formulas, * and ** represent bonding sites, and * represents a bond with A x1 represents a bond with TIFF0007696208000141.tif145161

[0204] 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.

[0205] ZA in formula (II-2-A’) + is the same as the cation Z1 in the salt represented by formula (B1). + The same ones can be mentioned.

[0206] The structural unit represented by formula (II-2-A’) is preferably the structural unit represented by formula (II-2-A). TIFF0007696208000142.tif38109 [In formula (II-2-A), R III3 、X III3 and ZA + represent the same meanings as above. z2A represents any integer from 0 to 6. R III2 and R III4 each independently represent a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. When z2A is 2 or more, a plurality of R III2 and R III4 may be the same as or different from each other. Q a and Q b each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. R III2 、R III4 、Q a and Q bExamples of the perfluoroalkyl group having 1 to 6 carbon atoms represented by include the same ones as the Q described above. b1 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms represented by include the same ones as the Q described above.

[0207] The structural unit represented by formula (II-2-A) is preferably the structural unit represented by formula (II-2-A-1). TIFF0007696208000143.tif5577 [In formula (II-2-A-1), R III2 、R III3 、R III4 、Q a 、Q b and ZA + have the same meanings as described above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. z2A1 represents any integer from 0 to 6. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, wherein -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -S- or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be replaced by a halogen atom or a hydroxy group. R III5 Examples of the saturated hydrocarbon group having 1 to 12 carbon atoms represented by include linear or branched alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group and dodecyl group. X I2 Examples of the divalent saturated hydrocarbon group represented by include the same ones as the divalent saturated hydrocarbon group represented by X III3 described above.

[0208] As the structural unit represented by formula (II-2-A-1), the structural unit represented by formula (II-2-A-2) is more preferable. TIFF0007696208000144.tif5287 [In formula (II-2-A-2), R III3 、RIII5 and ZA + represents the same meaning as described above. m and nA each independently represent 1 or 2.

[0209] Examples of the structural unit represented by formula (II-2-A') include, for example, the following structural units, R III3 wherein the group corresponding to the methyl group of R is replaced by a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group, etc.), and the structural units described in International Publication No. 2012 / 050015. ZA + represents an organic cation. TIFF0007696208000145.tif86163

[0210] The structural unit having a sulfonio group and an organic anion in the side chain is preferably a structural unit represented by formula (II-1-1). TIFF0007696208000146.tif3791[In formula (II-1-1), A II1 represents a single bond or a divalent linking group. R II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R II2 and R II3 each independently represent a hydrocarbon group having 1 to 18 carbon atoms, and R II2 and R II3 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. 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 R include a phenylene group and a naphthylene group, etc. R II2 and R II3Examples of the hydrocarbon group represented by include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. R II4 Examples of the halogen atom represented by include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R II4 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by include the same ones as the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by . a8 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by include the same ones as the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by . A II1 Examples of the divalent linking group represented by include, for example, a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-. Specifically, examples include the same ones as the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by . III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by include the same ones as the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by .

[0211] Examples of the structural unit containing a cation in formula (II-1-1) include a structural unit represented by the following and a structural unit in which a group corresponding to the methyl group of is replaced by a hydrogen atom, a fluorine atom, trifluoromethyl, etc. II4 Examples of the structural unit containing a cation in formula (II-1-1) include a structural unit represented by the following and a structural unit in which a group corresponding to the methyl group of is replaced by a hydrogen atom, a fluorine atom, trifluoromethyl, etc. TIFF0007696208000147.tif84130

[0212] A - Examples of the organic anion represented by include a sulfonate anion, a sulfonylimide anion, a sulfonylmethide anion, and a carboxylate anion. Examples of the organic anion represented by include a sulfonate anion, and it is more preferably an anion contained in the salt represented by the aforementioned formula (B1). - Examples of the organic anion represented by include a sulfonate anion, and it is more preferably an anion contained in the salt represented by the aforementioned formula (B1).

[0213] A - Examples of the sulfonylimide anion represented by include the following. TIFF0007696208000148.tif36135

[0214] Examples of the sulfonylmethide anion include the following. TIFF0007696208000149.tif29123

[0215] Examples of the carboxylic acid anion include the following. TIFF0007696208000150.tif51152

[0216] Examples of the structural unit represented by formula (II-1-1) include the structural units represented below. TIFF0007696208000151.tif88149

[0217] When the resin (A) contains the structural unit (II), the content of the structural unit (II) is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and even more preferably 3 to 10 mol% with respect to all the structural units of the resin (A).

[0218] The resin (A) may have structural units other than the above-described structural units, and examples of such structural units include structural units well-known in the art.

[0219] The resin (A) is preferably a resin composed of the structural unit (a1) and the structural unit (s), that is, a copolymer of the monomer (a1) and the monomer (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group and a cyclopentyl group), more preferably at least two kinds, and even more preferably at least two kinds selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit(s) is preferably at least one selected from the group consisting of structural unit (a2) and structural unit (a3). The structural unit (a2) is preferably structural unit (a2-1) or 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). Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using the monomer that leads to these structural units. The content of each structural unit of the resin (A) can be adjusted by the amount of the monomer used in the polymerization. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less). In this specification, the weight average molecular weight is the value determined by gel permeation chromatography under the conditions described in the examples.

[0220] <Resin other than resin (A)> The resist composition of the present invention may use a resin other than the resin (A) in combination. Examples of the resin other than the resin (A) include a resin containing the structural unit (a4) or the structural unit (a5) (hereinafter sometimes referred to as resin (X)). Among them, the resin containing the structural unit (a4) is preferable as the 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, still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Examples of the structural unit that the resin (X) may further have include the structural unit (a1), the structural unit (a2), the structural unit (a3), and the structural unit derived from other known monomers. Among them, the resin (X) is preferably a resin consisting of only the structural unit (a4) and / or the structural unit (a5). Each structural unit constituting the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using the monomers that induce these structural units. The content rate of each structural unit that the resin (X) has can be adjusted by the usage amount of the monomers used for polymerization. The weight average molecular weight of the resin (X) is preferably 6,000 or more (more preferably 7,000 or more), and 80,000 or less (more preferably 60,000 or less). The measuring means of the weight average molecular weight of the resin (X) is the same as that of the resin (A).

[0221] When the resist composition of the present invention contains the resin (X), its content rate is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, still more preferably 1 to 40 parts by mass, even more preferably 1 to 30 parts by mass, and particularly preferably 1 to 8 parts by mass with respect to 100 parts by mass of the resin (A).

[0222] The content rate of the resin (A) in the resist composition is preferably 80% by mass or more and 99% by mass or less, and more preferably 90% by mass or more and 99% by mass or less with respect to the solid content of the resist composition. Also, when containing a resin other than the resin (A), the total content rate of the resin (A) and the resin other than the resin (A) is preferably 80% by mass or more and 99% by mass or less, and more preferably 90% by mass or more and 99% by mass or less with respect to the solid content of the resist composition. In this specification, "the solid content of the resist composition" means the total of the components excluding the solvent (E) described later from the total amount of the resist composition. The solid content of the resist composition and the content rate of the resin with respect to this can be measured by known analysis means such as liquid chromatography or gas chromatography.

[0223] <Solvent (E)> The content rate of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less, preferably 92% by mass or more and 99% by mass or less, and more preferably 94% by mass or more and 99% by mass or less. The content rate of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0224] 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 kind of the solvent (E) may be used alone, or two or more kinds may be used.

[0225] <Quencher (C)> Examples of the quencher (C) include basic nitrogen-containing organic compounds and salts that generate an acid having a lower acidity than the acid generated from the acid generator (B). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15% by mass, more preferably about 0.01 to 10% by mass, still more preferably about 0.1 to 5% by mass, and still more preferably about 0.1 to 3% by mass based on the solid content of the resist composition. Examples of the basic nitrogen-containing organic compounds include amines and ammonium salts. Examples of the amines include aliphatic amines and aromatic amines. Examples of the aliphatic amines include primary amines, secondary amines, and tertiary amines.

[0226] Examples of the amine include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 1,2-di(4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridylsulfide, 4,4'-dipyridyldisulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine, etc. Of these, diisopropylaniline is preferred, and 2,6-diisopropylaniline is more preferred.

[0227] Examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, choline, and the like.

[0228] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is indicated by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is a salt having an acid dissociation constant of the acid generated from the salt usually of -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. Preferably, it is a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (B) (a salt having a carboxylic acid anion), and more preferably, it is the weak acid inner salt (D). TIFF0007696208000152.tif89165

[0229] Examples of the weak acid inner salt (D) include the following salts. TIFF0007696208000153.tif72165

[0230] 〈Other Components〉 The resist composition of the present invention may contain, if necessary, components other than the above-described components (hereinafter sometimes referred to as "other components (F)"). There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used.

[0231] 〈Preparation of Resist Composition〉 The resist composition of the present invention can be prepared by mixing salt (I), resin (A) and acid generator (B), and, if necessary, a resin other than resin (A) used, solvent (E), quencher (C) and other components (F). The mixing order is arbitrary and not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40°C according to the type of resin, etc. and the solubility of the resin, etc. in solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is also not particularly limited, and stirring and mixing, etc. can be used. After mixing the respective components, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

[0232] 〈Method for Manufacturing Resist Pattern〉 The method for manufacturing a resist pattern of the present invention (1) A step of applying the resist composition of the present invention onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer.

[0233] To apply the resist composition onto a substrate, it can be carried out by a commonly used apparatus such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers. Before applying the resist composition, the substrate may be cleaned, or an antireflection film, etc. may be formed on the substrate.

[0234] By drying the applied composition, the solvent is removed to form a composition layer. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or by using a decompression device. The heating temperature is preferably 50 to 200 °C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during vacuum drying is preferably about 1 to 1.0×10 5 Pa.

[0235] The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, those that emit laser light in the ultraviolet region such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), those that convert the laser light from a solid laser light source (such as YAG or semiconductor laser) into harmonic laser light in the far ultraviolet region or vacuum ultraviolet region and emit it, those that irradiate electron beams, extreme ultraviolet light (EUV), etc., various ones can be used. In this specification, irradiating these radiations may be collectively referred to as "exposure". During exposure, usually, exposure is performed through a mask corresponding to the required pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask.

[0236] The exposed composition layer is heat-treated (so-called post-exposure bake) to promote the deprotection reaction in the acid-labile group. The heating temperature is usually about 50 to 200 °C, preferably about 70 to 150 °C.

[0237] The heated composition layer is usually developed using a developing solution with a developing device. Examples of the developing method include dip method, paddle method, spray method, dynamic dispense method, etc. The developing temperature is preferably, for example, 5 to 60 °C, and the developing time is preferably, for example, 5 to 300 seconds. By selecting the type of developing solution as follows, a positive resist pattern or a negative resist pattern can be manufactured.

[0238] When producing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. For example, aqueous solutions of tetramethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline), etc. may be mentioned. The alkaline developer may contain a surfactant. After development, it is preferable to wash the resist pattern with ultrapure water and then remove the water remaining on the substrate and the pattern.

[0239] When producing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic developer") is used as the developer. Examples of the organic solvent contained in the organic developer include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole, etc. In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and even more preferably substantially only the organic solvent. Among them, as the organic developer, a developer containing butyl acetate and / or 2-heptanone is preferable. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant. Also, the organic developer may contain a small amount of water. During development, development may be stopped by substituting with a solvent of a different type from the organic developer.

[0240] It is preferable to wash the developed resist pattern with a rinse solution. The rinse solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After washing, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

[0241] <Usage> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, particularly as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for semiconductor microfabrication.

Examples

[0242] The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing content or usage amount are based on mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography. The analysis conditions for gel permeation chromatography are as follows. Column: TSKgel Multipore HXL-M x 3+guard column (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 °C Injection volume: 100 μl Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC is Agilent model 1100, MASS is Agilent LC / MSD model). In the following examples, the value of this molecular ion peak is indicated by “MASS”.

[0243] Example 1: Synthesis of the salt represented by formula (I-2) 10 parts of the salt represented by TIFF0007696208000154.tif42149 formula (I-1-a) and 50 parts of dimethylformamide were mixed and stirred at 23 °C for 30 minutes. Then, 1.60 parts of potassium carbonate and 0.48 parts of potassium iodide were added, and the temperature was raised to 75 °C. To the resulting mixture, 11.27 parts of the compound represented by formula (I-1-b) were added, and the mixture was stirred at 75 °C for 5 hours and then cooled to 23 °C. To the resulting mixture, 100 parts of chloroform and 45 parts of 5% aqueous oxalic acid solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. To the obtained organic layer, 50 parts of ion-exchanged water were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. This water washing operation was repeated 5 times. By concentrating the obtained organic layer, 13.94 parts of the compound represented by formula (I-1-c) were obtained. 3.04 parts of the salt represented by TIFF0007696208000155.tif35164 formula (I-1-c), 3.06 parts of the salt represented by formula (I-2-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water were added and stirred at 23 °C for 30 minutes, and then the layers were separated to obtain the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and to the concentrated residue, 30 parts of tert-butyl methyl ether were added and stirred at 23 °C for 30 minutes, and then filtered to obtain 4.15 parts of the salt represented by formula (I-2).

[0244] MASS(ESI(+)Spectrum):M + 485.2 MASS(ESI(-)Spectrum):M - 517.1

[0245] Example 2: Synthesis of the salt represented by formula (I-1) 3.04 parts of the salt represented by formula (I-1-c), 2.99 parts of the salt represented by formula (I-1-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to extract the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and 30 parts of tert-butyl methyl ether was added to the concentrated residue and stirred at 23 °C for 30 minutes, and then filtered to obtain 4.15 parts of the salt represented by formula (I-1).

[0246] MASS(ESI(+)Spectrum):M + 485.2 MASS(ESI(-)Spectrum):M - 503.1

[0247] Example 3: Synthesis of the salt represented by formula (I-21) 10.65 parts of the salt represented by formula (I-21-a) and 50 parts of dimethylformamide were mixed and stirred at 23 °C for 30 minutes, then 1.60 parts of potassium carbonate and 0.48 part of potassium iodide were added, and the temperature was raised to 75 °C. To the resulting mixture, 11.27 parts of the compound represented by formula (I-1-b) was added, and the mixture was stirred at 75 °C for 5 hours and then cooled to 23 °C. To the resulting mixture, 100 parts of chloroform and 45 parts of 5% oxalic acid aqueous solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to extract the organic layer. To the obtained organic layer, 50 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to extract the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated to obtain 11.89 parts of the compound represented by formula (I-21-c). 3.17 parts of the salt represented by formula (I-21-c), 2.99 parts of the salt represented by formula (I-1-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and to the concentrated residue, 30 parts of tert-butyl methyl ether was added and stirred at 23 °C for 30 minutes, and then filtered to obtain 4.01 parts of the salt represented by formula (I-21).

[0248] MASS(ESI(+)Spectrum):M + 513.3 MASS(ESI(-)Spectrum):M - 503.1

[0249] Example 4: Synthesis of the salt represented by formula (I-42) 10 parts of the salt represented by formula (I-42-a) and 50 parts of dimethylformamide were mixed and stirred at 23 °C for 30 minutes, then 1.48 parts of potassium carbonate and 0.44 parts of potassium iodide were added, and the temperature was raised to 75 °C. To the resulting mixture, 10.40 parts of the compound represented by formula (I-1-b) was added, and the mixture was stirred at 75 °C for 5 hours and then cooled to 23 °C. To the resulting mixture, 100 parts of chloroform and 45 parts of 5% oxalic acid aqueous solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to take out the organic layer. To the obtained organic layer, 50 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated to obtain 12.89 parts of the compound represented by formula (I-42-c). 3.21 parts of the salt represented by formula (I-42-c), 3.06 parts of the salt represented by formula (I-2-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, followed by liquid separation to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, and 30 parts of tert-butyl methyl ether was added to the concentrated residue and stirred at 23 °C for 30 minutes, followed by filtration to obtain 4.56 parts of the salt represented by formula (I-42).

[0250] MASS(ESI(+)Spectrum):M + 521.2 MASS(ESI(-)Spectrum):M - 517.1

[0251] Example 5: Synthesis of the salt represented by formula (I-62) 10 parts of the salt represented by formula (I-62-a) and 50 parts of dimethylformamide were mixed and stirred at 23 °C for 30 minutes, then 1.22 parts of potassium carbonate and 0.36 part of potassium iodide were added, and the temperature was raised to 75 °C. To the resulting mixture, 8.56 parts of the compound represented by formula (I-1-b) was added and stirred at 75 °C for 5 hours, then cooled to 23 °C. To the obtained mixture, 100 parts of chloroform and 45 parts of 5% oxalic acid aqueous solution were added and stirred at 23 °C for 30 minutes, followed by liquid separation to take out the organic layer. To the obtained organic layer, 50 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, followed by liquid separation to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated to obtain 11.72 parts of the compound represented by formula (I-62-c). 3.69 parts of the salt represented by formula (I-62-c), 3.06 parts of the salt represented by formula (I-2-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then liquid separation was carried out to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, 30 parts of tert-butyl methyl ether was added to the concentrated residue, stirred at 23 °C for 30 minutes, and then filtered to obtain 4.88 parts of the salt represented by formula (I-62).

[0252] MASS(ESI(+)Spectrum):M + 621.2 MASS(ESI(-)Spectrum):M - 517.1

[0253] Example 6: Synthesis of the salt represented by formula (I-302) 10 parts of the salt represented by formula (I-302-a) and 50 parts of dimethylformamide were mixed and stirred at 23 °C for 30 minutes, then 1.01 parts of potassium carbonate and 0.30 parts of potassium iodide were added, and the temperature was raised to 75 °C. To the resulting mixture, 7.10 parts of the compound represented by formula (I-1-b) was added, stirred at 75 °C for 5 hours, and then cooled to 23 °C. To the obtained mixture, 100 parts of chloroform and 45 parts of 5% oxalic acid aqueous solution were added and stirred at 23 °C for 30 minutes, and then liquid separation was carried out to take out the organic layer. To the obtained organic layer, 50 parts of ion-exchanged water was added, stirred at 23 °C for 30 minutes, and then liquid separation was carried out to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated to obtain 10.48 parts of the compound represented by formula (I-302-c). 4.24 parts of the salt represented by formula (I-302-c), 3.06 parts of the salt represented by formula (I-2-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, 30 parts of tert-butyl methyl ether was added to the concentrated residue, and the mixture was stirred at 23 °C for 30 minutes and then filtered to obtain 4.89 parts of the salt represented by formula (I-302).

[0254] MASS(ESI(+)Spectrum):M + 737.0 MASS(ESI(-)Spectrum):M - 517.1

[0255] Example 7: Synthesis of the salt represented by formula (I-362) 5.19 parts of the salt represented by formula (I-362-a) and 50 parts of dimethylformamide were mixed and stirred at 23 °C for 30 minutes, then 1.60 parts of potassium carbonate and 0.48 part of potassium iodide were added, and the temperature was raised to 75 °C. To the resulting mixture, 11.27 parts of the compound represented by formula (I-1-b) was added, and the mixture was stirred at 75 °C for 5 hours and then cooled to 23 °C. To the resulting mixture, 100 parts of chloroform and 45 parts of 5% oxalic acid aqueous solution were added and stirred at 23 °C for 30 minutes, and then the layers were separated to take out the organic layer. To the obtained organic layer, 50 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then the layers were separated to take out the organic layer. This water washing operation was repeated 5 times. The obtained organic layer was concentrated to obtain 8.24 parts of the compound represented by formula (I-362-c). 4.10 parts of the salt represented by formula (I-362-c), 3.06 parts of the salt represented by formula (I-2-d), 30 parts of chloroform and 15 parts of ethyl acetate were mixed and stirred at 23 °C for 2 hours. To the resulting mixture, 20 parts of ion-exchanged water was added and stirred at 23 °C for 30 minutes, and then liquid separation was carried out to take out the organic layer. This washing operation with water was repeated 5 times. The obtained organic layer was concentrated, 30 parts of tert-butyl methyl ether was added to the concentrated residue and stirred at 23 °C for 30 minutes, and then filtered to obtain 4.89 parts of the salt represented by formula (I-362).

[0256] MASS(ESI(+)Spectrum):M + 707.3 MASS(ESI(-)Spectrum):M - 517.1

[0257] Synthesis of resin The compounds (monomers) used for the synthesis of resin (A) are shown below. Hereinafter, these compounds are referred to as "monomer (a1-1-3)" etc. according to their formula numbers. TIFF0007696208000167.tif4192

[0258] Synthesis Example 1 [Synthesis of Resin A1] As monomers, monomer (a1-4-2), monomer (a1-1-3) and monomer (a1-2-6) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-1-3): monomer (a1-2-6)] was 38:24:38. Further, 1.5 times the mass of methyl isobutyl ketone with respect to the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% with respect to the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Then, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the mass with respect to the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was carried out. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and the weight average molecular weight was about 5.3×10 3 Resin A1 (copolymer) with a yield of 78% was obtained. This resin A1 has the following structural units. TIFF0007696208000168.tif29126

[0259] Synthesis Example 2 [Synthesis of Resin A2] As monomers, monomer (a1-4-2) and monomer (a1-2-6) were used, and they were mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6)] was 38:62. Further, 1.5 times the mass of methyl isobutyl ketone with respect to the total mass of all monomers was mixed into this monomer mixture. To the obtained mixture, azobisisobutyronitrile was added as an initiator so as to be 7 mol% with respect to the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Then, an aqueous solution of p-toluenesulfonic acid (2.5 wt%) 2.0 times the mass with respect to the total mass of all monomer amounts was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was carried out. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and the weight average molecular weight was about 5.4×10 3 Resin A2 (copolymer) with a yield of 89% was obtained. This resin A2 has the following structural units. TIFF0007696208000169.tif2887

[0260] <Preparation of Resist Composition> As shown in Table 2, the following components were mixed, and the resulting mixture was filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a resist composition.

[0261]

Table 2

[0262] <Resin> A1, A2: Resin A1, Resin A2 <Salt (I)> I-1: Salt represented by formula (I-1) I-2: Salt represented by formula (I-2) I-21: Salt represented by formula (I-21) I-42: Salt represented by formula (I-42) I-62: Salt represented by formula (I-62) I-302: Salt represented by formula (I-302) I-362: Salt represented by formula (I-362) <Acid Generator> IX-1: TIFF0007696208000171.tif3082IX-2: TIFF0007696208000172.tif3093IX-3: TIFF0007696208000173.tif4296<Quencher (C)> C1: Synthesized by the method described in JP-A-2011-39502 TIFF0007696208000174.tif4355<Solvent> 400 parts of propylene glycol monomethyl ether acetate 100 parts of propylene glycol monomethyl ether 5 parts of γ-butyrolactone

[0263] (Electron Beam Exposure Evaluation of Resist Composition) A 6-inch silicon wafer was treated with hexamethyldisilazane at 90 °C for 60 seconds on a direct hot plate. A resist composition was spin-coated onto this silicon wafer so that the film thickness of the composition layer was 0.04 μm. Then, it was pre-baked for 60 seconds at the temperature shown in the "PB" column of Table 2 on a direct hot plate to form a composition layer. Using an electron beam lithography machine ["ELS-F125 125 keV" manufactured by Elionix, Inc.], a contact hole pattern (hole pitch 40 nm / hole diameter 17 nm) was directly drawn on the composition layer formed on the wafer while changing the exposure dose step by step. After exposure, post-exposure baking was performed for 60 seconds at the temperature shown in the "PEB" column of Table 2 on a hot plate, and further paddle development was performed for 60 seconds with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide to obtain a resist pattern.

[0264] In the resist pattern obtained after development, the exposure dose at which the formed hole diameter became 17 nm was defined as the effective sensitivity.

[0265] <CD Uniformity (CDU) Evaluation> At the effective sensitivity, the hole diameter of the pattern formed with a hole diameter of 17 nm was measured 24 times for each hole, and the average value was taken as the average hole diameter of one hole. Using as the population the measurement of the average hole diameter of the patterns formed with a hole diameter of 17 nm at 400 locations within the same wafer, the standard deviation was determined. The results are shown in Table 3. The numerical values in the table indicate the standard deviation (nm).

[0266]

Table 3

Industrial Applicability

[0267] The resist composition containing the salt of the present invention is suitable for fine processing of semiconductors because it can obtain a resist pattern having good CD uniformity (CDU), and is extremely useful industrially.

Claims

1. A salt represented by formula (I). [In formula (I), R １ represents -O-L １ -CO-O-R ５ represents. L １ represents an alkanediyl group having 1 to 6 carbon atoms. R ５ represents an acid-labile group which is a group represented by formula (1a). R ２ , R ３ and R ４ each independently represents a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms, a hydrocarbon group having 1 to 18 carbon atoms or -O-L １ -CO-O-R ５ represents, and -CH 2 - contained in the hydrocarbon group may be replaced by -O- or -CO-. m2 represents any integer from 0 to 4, and when m2 is 2 or more, a plurality of R ２ may be the same as or different from each other. m3 represents any integer from 0 to 5, and when m3 is 2 or more, a plurality of R ３ may be the same as or different from each other. m4 represents any integer from 0 to 5, and when m4 is 2 or more, a plurality of R ４ may be the same as or different from each other. Q 1 and Q 2 each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. R １１ and R １２ each independently represents a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents 0 or 1. X 1 is *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * is C(R １1 )(R １2 ) or C(Q 1 )(Q 2Represents the bonding position with (). Represents (). A １ represents *-L2-CO-O-, and L2 represents a group represented by the following formula (L2-1), formula (L2-2), formula (L2-3) or formula (L2-4) (* represents a bond). R １３ represents an adamantyl group, a hydroxyadamantyl group or an adamantanone group which may have an alkyl group having 1 to 4 carbon atoms.] [In formula (1a), R aa3 represents an alkyl group having 1 to 8 carbon atoms, R aa1 and R aa2 are bonded to each other to form a cyclopentyl group, a cyclohexyl group or an adamantyl group together with the carbon atom to which they are bonded. * represents a bond.]

2. X １ is *-CO-O-, and the salt according to claim 1

3. m3 is any integer from 1 to 2, m4 is any integer from 0 to 2, R ３ and R ４ wherein either one of them is a fluorine atom, an iodine atom or trifluoromethyl, and the salt according to claim 1 or 2

4. m3 is any integer from 1 to 2, m4 is any integer from 0 to 2, R ３ and R ４ wherein either one of them is -O-L １ -CO-O-R ５ and a plurality of R ５ may be the same as or different from each other, and the salt according to any one of claims 1 to 3

5. m2 is 1 or 2, and at least one of a plurality of R ２ is -O-L １ -CO-O-R ５ and a plurality of R ５ is a salt according to any one of claims 1 to 4, which may be the same as or different from each other. **Claim 6** An acid generator containing the salt according to any one of claims 1 to 5. **Claim 7** A resist composition containing the acid generator according to claim 6 and a resin having an acid-labile group. **Claim 8** The resist composition according to claim 7, wherein the resin having an acid-labile group contains 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). [In formula (a1-1) and formula (a1-2), L ａ１ and L ａ２ each independently represents -O- or *-O-(CH ２ ) ｋ１ -CO-O-, k1 represents an integer of any one of 1 to 7, and * represents a bond 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 group combining these. m1 represents an integer of any one of 0 to 14. n1 represents an integer of any one of 0 to 10. n1' represents an integer of any one of 0 to 3. ] **Claim 9** The resist composition according to claim 7 or 8, wherein the resin having an acid-labile group contains a structural unit represented by formula (a2-A). [In formula (a2-A), R a50represents 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 represents a single bond or *-X a51 -(A a52 -X a52 ) nｂ -, where * represents a bond to the carbon atom to which -R a50 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 any integer from 0 to 4. When mb is any integer of 2 or more, a plurality of R a51 may be the same as or different from each other. ]

10. The resist composition according to any one of claims 7 to 9, further containing a salt that generates an acid having a lower acidity than the acid generated from the acid generator.

11. (1) A step of applying the resist composition according to any one of claims 7 to 10 onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, A method for producing a resist pattern, including these steps.

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