Carboxylic acid salt, carboxylic acid generator, resist composition and method for producing resist pattern

Abstract

To provide a carboxylate, a carboxylic acid generator, and a resist composition capable of producing a resist pattern with a good mask error factor (MEF).SOLUTION: A carboxylate represented by Formula (I), a carboxylic acid generator, and a resist composition are provided. [In the formula, R1a and R2a each represent H, a hydrocarbon group which may have F, or the like; R3a represents H, or R1a, R2a and R3a are bonded together to form a ring which may have F or an alkyl group; R4 and R5 each independently represent a halogen atom, a fluorinated alkyl group or the like; m4 represents an integer of 0-4; m5 represents an integer of 0-5; and X0 represents an optionally substituted hydrocarbon group.]SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a carboxylate, a carboxylic acid generator, a resist composition, and a method for producing a resist pattern. [Background technology]

[0002] Patent Document 1 describes a resist composition that contains a carboxylate represented by the following formula as a carboxylic acid generator. TIFF0007624807000001.tif3050 Patent Document 2 describes a resist composition that contains a carboxylate represented by the following formula as a carboxylic acid generator. TIFF0007624807000002.tif3052 Patent Document 3 describes a salt represented by the following formula: TIFF0007624807000003.tif1750

[0003] Patent Document 4 describes a salt represented by the following formula: TIFF0007624807000004.tif21112 [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-39502 A [Patent Document 2] JP 2014-88367 A [Patent Document 3] Japanese Unexamined Patent Publication No. 49-123860 [Patent Document 4] JP 2018-030830 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention provides a carboxylate that forms a resist pattern with a better mask error factor (MEF) than a resist pattern formed using a resist composition containing the above-mentioned carboxylate. [Means for solving the problem]

[0006] The present invention includes the following inventions. [1] A carboxylate represented by formula (I). TIFF0007624807000005.tif48113 [In formula (I), R 1a and R 2a each independently represents a hydrocarbon group having 1 to 18 carbon atoms which may have a hydrogen atom or a fluorine atom (-CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or R 1a and R 2a and bond to each other to form a ring having 3 to 36 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-). R 3a represents a hydrogen atom or R 1a and R 2a and R 3a and bond to each other to form a ring having 3 to 36 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-). R 4 represents a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 12 carbon atoms, and -CH2- contained in the fluorinated alkyl group and the alkyl group may be replaced by -O- or -CO-. R 5 is a halogen atom, a fluoroalkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or -O-CO-CR 1bR 2b R 3b wherein -CH2- contained in the fluorinated alkyl group and the alkyl group may be replaced by -O- or -CO-. R 1b and R 2b each independently represents a hydrocarbon group having 1 to 18 carbon atoms which may have a hydrogen atom or a fluorine atom (-CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or R 1b and R 2b and bond to each other to form a ring having 3 to 36 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-). R 3b represents a hydrogen atom or R 1b and R 2b and R 3b and bond to each other to form a ring having 3 to 36 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-). m4 represents an integer of 0 to 4, and when m4 is 2 or more, a plurality of R 4 may be the same or different from each other. m5 represents an integer of 0 to 5, and when m5 is 2 or more, a plurality of R 5 may be the same or different from each other. X 0 represents a hydrocarbon group having 1 to 72 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.] [2]X 0is an aliphatic hydrocarbon group having 1 to 72 carbon atoms which may have a substituent (provided that -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). [3]X 0 is an alicyclic hydrocarbon group which may have a fluorine atom or a hydroxy group (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-) or a group in combination of an alicyclic hydrocarbon group and a chain hydrocarbon group (-CH2- contained in the alicyclic hydrocarbon group and the chain hydrocarbon group may be replaced by -O- or -CO-, and the alicyclic hydrocarbon group and the chain hydrocarbon group may have a fluorine atom or a hydroxy group). [4] A carboxylic acid generator comprising the carboxylate according to any one of [1] to [3]. [5] A resist composition comprising the carboxylic acid generator according to [4], an acid generator other than the carboxylic acid generator, and a resin having an acid labile group. [6] The resist composition according to [5], wherein the resin having an acid labile group is a resin containing at least one selected from the group consisting of a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2): TIFF0007624807000006.tif46102 [In formula (a1-1) and formula (a1-2), L a1 and L a2 are each independently -O- or *-O-(CH2) k1 represents --CO--O--; k1 represents an integer of 1 to 7; and * represents a bond to --CO--. R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a combination thereof. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. [7] The resist composition according to [5] or [6], further comprising a resin containing a structural unit having a fluorine atom. [8] (1) A step of applying the resist composition according to any one of [5] to [7] onto a substrate; (2) A step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) A method for producing a resist pattern, comprising the step of developing the composition layer after heating. Effect of the Invention

[0007] By using a resist composition that uses a carboxylate of the present invention, a resist pattern can be produced with an excellent mask error factor (MEF). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In this specification, "(meth)acrylic monomer" means at least one selected from the group consisting of monomers having the structure "CH2=CH-CO-" and monomers having the structure "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, a structural unit having both groups is also exemplified. In addition, in the group described in this specification, either a linear structure or a branched structure may be used for those that can have both. "Combined group" means a group in which two or more of the exemplified groups are bonded, and the valence of the group may be appropriately changed depending on the bond form. "Derived from" or "derived from" refers to a polymerizable C=C bond contained in the molecule being polymerized to a -CC- group. Where stereoisomers exist, all stereoisomers are included. In this specification, the term "solids content of a resist composition" refers to the sum of the components excluding the solvent (E), which will be described later, from the total amount of the resist composition.

[0009] [Salt represented by formula (I)] The present invention relates to a carboxylate represented by formula (I) (hereinafter sometimes referred to as "carboxylate (I)"). In salt (I), the negatively charged side is sometimes called the "anion (I)" and the positively charged side is sometimes called the "cation (I)". TIFF0007624807000007.tif48113 [wherein all symbols have the same meanings as defined above.]

[0010] R 1a , R 1b , R 2a and R 2b Examples of the hydrocarbon group include chain hydrocarbon groups such as alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, still more preferably 1 to 4, and still more preferably 1 to 2. The alicyclic hydrocarbon group may be any of monocyclic, polycyclic, and spirocyclic, and may be any of saturated and unsaturated. Examples of the alicyclic hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl, and polycyclic cycloalkyl groups such as norbornyl and adamantyl. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, etc. The aromatic hydrocarbon group preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and further preferably 6 to 10 carbon atoms. Examples of groups formed by combining these include groups formed by combining an alicyclic hydrocarbon group with a chain hydrocarbon group, such as a cyclopentylmethyl group and an adamantylmethyl group, and groups formed by combining an aromatic hydrocarbon group with a chain hydrocarbon group, such as a benzyl group and a phenethyl group. In the case of a group formed by combining the above groups, the above groups may contain groups having different valencies (divalent or trivalent groups (chain hydrocarbon groups, alicyclic saturated hydrocarbon groups, aromatic hydrocarbon groups, etc.)). R 1a , R 2a , R 1b and R 2b A hydrocarbon group represented by R 1a and R 2a , R 1b and R 2b , R 1a and R 2a and R 3a or R 1b and R 2b and R 3b When -CH2- in the ring formed by bonding with each other is replaced with -O-, -S-, -CO- or -SO2-, the number of carbon atoms before the replacement is the total number of carbon atoms in the hydrocarbon group or the ring. 1a and R 2a , R 1a and R 2a and R 3a , R 1b and R 2b or R 1b and R 2b and R 3b When the ring formed by bonding together contains an alkyl group, the number of carbon atoms in the alkyl group is excluded from the number of carbon atoms in the ring. R 1a , R 2a , R 1b or R 2bWhen R is a hydrocarbon group, the number of carbon atoms in the hydrocarbon group is preferably 1 to 18, more preferably 1 to 14, and further preferably 1 to 12. 1a and R 2a , R 1b and R 2b , R 1a and R 2a and R 3a or R 1b and R 2b and R 3b When they are bonded to each other to form a ring, each of the rings independently preferably has 3 to 24 carbon atoms, more preferably has 3 to 18 carbon atoms, and further preferably has 3 to 16 carbon atoms. R 1a and R 2a , R 1a and R 2a and R 3a , R 1b and R 2b or R 1b and R 2b and R 3b Examples of the alkyl group which may be possessed when and are bonded to each other to form a ring include the same groups as those mentioned above.

[0011] Examples of the group in which -CH2- in an alkyl group is replaced with -O- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), an alkoxy group having 1 to 11 carbon atoms (a group in which -CH2- in an alkyl group having 2 to 12 carbon atoms is replaced with -O-), and an alkoxy group having 2 to 11 carbon atoms. Examples of such groups include a carbonyl group (a group in which -CH2-CH2- in an alkyl group having 3 to 12 carbon atoms is replaced with -O-CO-), an alkylcarbonyl group having 2 to 12 carbon atoms (a group in which -CH2- in an alkyl group having 2 to 12 carbon atoms is replaced with -CO-), and an alkylcarbonyloxy group having 2 to 11 carbon atoms (a group in which -CH2-CH2- in an alkyl group having 3 to 12 carbon atoms is replaced with -CO-O-). 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 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, and an undecyloxy group. The alkoxycarbonyl group, alkylcarbonyl group and alkylcarbonyloxy group represent groups in which a carbonyl group or a carbonyloxy group is bonded to the above-mentioned alkyl group or alkoxy group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group.

[0012] R 1a and R 2a , R 1a and R 2a and R 3a , R 1b and R 2b or R 1b and R 2b and R 3b When and are bonded to each other to form a ring, -C(R 1a )(R 2a )(R 3a ) or -C(R 1b )(R 2b )(R 3b ) includes the following groups. * represents the bonding site with the carbon atom of the carbonyl group. TIFF0007624807000008.tif86163R 1a , R 2a , R 1b and R 2b are each independently a hydrogen atom, a hydrocarbon group having 1 to 14 carbon atoms which may have a fluorine atom (-CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or R 1a and R 2a , R 1b and R 2band are preferably bonded to each other to form a ring having 3 to 24 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-), each independently represents a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms which may have a fluorine atom (-CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or R 1a and R 2a , R 1b and R 2b and more preferably are bonded to each other to form a ring having 3 to 16 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-), each independently represents a hydrogen atom, a chain hydrocarbon group having 1 to 12 carbon atoms, an adamantyl group which may have a fluorine atom (-CH2- contained in the adamantyl group may be replaced by -O-, -S-, -CO- or -SO2-), or a spiro ring containing an adamantyl group which may have a fluorine atom (-CH2- contained in the adamantyl group and the spiro ring may be replaced by -O-, -S-, -CO- or -SO2-), or R 1a and R 2a , R 1b and R 2band are bonded to each other to form an adamantyl group which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the adamantyl group may be replaced with -O-, -S-, -CO- or -SO2-), or a spiro ring containing an adamantyl group which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the adamantyl group and the spiro ring may be replaced with -O-, -S-, -CO- or -SO2-), each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an adamantyl group which may have a fluorine atom (-CH- contained in the adamantyl group may be replaced by -O-, -S-, -CO- or -SO-), or R 1a and R 2a , R 1b and R 2b and the like are bonded to each other to form an adamantyl group which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the adamantyl group may be replaced with -O-, -S-, -CO- or -SO2-).

[0013] R 3a and R 3b are each independently a hydrogen atom or R 1a and R 2a and R 3a or R 1b and R 2b and R 3b and are preferably bonded to each other to form a ring having 3 to 24 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-), Hydrogen atom or R 1a and R2a and R 3a or R 1b and R 2b and R 3b and more preferably are bonded to each other to form a ring having 3 to 16 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the ring may be replaced with -O-, -S-, -CO- or -SO2-), Hydrogen atom or R 1a and R 2a and R 3a or R 1b and R 2b and R 3b and are bonded to each other to form an adamantyl group which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the adamantyl group may be replaced with -O-, -S-, -CO- or -SO2-), or a spiro ring containing an adamantyl group which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the adamantyl group and the spiro ring may be replaced with -O-, -S-, -CO- or -SO2-), Hydrogen atom or R 1a and R 2a and R 3a or R 1b and R 2b and R 3b and the like are bonded to each other to form an adamantyl group which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and -CH2- contained in the adamantyl group may be replaced with -O-, -S-, -CO- or -SO2-).

[0014] R 4 and R 5 Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom. R 4 and R 5 Examples of the fluorinated alkyl group having 1 to 6 carbon atoms include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, etc. The number of carbon atoms of the fluorinated alkyl group is preferably 1 to 4, and more preferably 1 to 3. R 4 and R 5 Examples of the alkyl group having 1 to 12 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, and a nonyl group. The number of carbon atoms in the alkyl group is preferably 1 to 9, more preferably 1 to 6, and further preferably 1 to 4. R 4 and R 5 When -CH2- contained in the fluorinated alkyl group and the alkyl group represented by the following formula is replaced with -O- or -CO-, the number of carbon atoms before replacement is regarded as the total number of carbon atoms in the fluorinated alkyl group and the alkyl group. R 4 and R 5Examples of the group in which -CH2- in an alkyl group represented by the formula (I) is replaced with -O- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), an alkoxy group having 1 to 11 carbon atoms (a group in which -CH2- in an alkyl group having 2 to 12 carbon atoms is replaced with -O-), an alkoxy group having 2 to 11 carbon atoms (a group in which -CH2- in an alkyl group having 2 to 12 carbon atoms is replaced with -O-), Examples of such groups include a carbonoxycarbonyl group (a group in which -CH2-CH2- in an alkyl group having 3 to 12 carbon atoms is replaced with -O-CO-), an alkylcarbonyl group having 2 to 12 carbon atoms (a group in which -CH2- in an alkyl group having 2 to 12 carbon atoms is replaced with -CO-), and an alkylcarbonyloxy group having 2 to 11 carbon atoms (a group in which -CH2-CH2- in an alkyl group having 3 to 12 carbon atoms is replaced with -CO-O-). R 4 and R 5 Examples of the group in which -CH2- in a fluorinated alkyl group represented by the formula (I) is replaced with -O- or -CO- include a fluorinated alkoxy group having 1 to 5 carbon atoms (a group in which -CH2- in a fluorinated alkyl group having 2 to 6 carbon atoms is replaced with -O-), a fluorinated alkoxycarbonyl group having 2 to 5 carbon atoms (a group in which -CH2-CH2- in a fluorinated alkyl group having 3 to 6 carbon atoms is replaced with -O-CO-), a fluorinated alkylcarbonyl group having 2 to 6 carbon atoms (a group in which -CH2- in a fluorinated alkyl group having 2 to 6 carbon atoms is replaced with -CO-), and a fluorinated alkylcarbonyloxy group having 2 to 5 carbon atoms (a group in which -CH2-CH2- in a fluorinated alkyl group having 3 to 6 carbon atoms is replaced with -CO-O-). Examples of the alkoxy group, the alkoxycarbonyl group, the alkylcarbonyl group and the alkylcarbonyloxy group include the same groups as those mentioned above. The fluorinated alkoxy group, fluorinated alkoxycarbonyl group, fluorinated alkylcarbonyl group and fluorinated alkylcarbonyloxy group can be obtained by replacing one or more hydrogen atoms of the above-exemplified groups with fluorine atoms. R 4 and R 5 is -O-CO-C(R 1a )(R2a )(R 3a ) may be the same group as or different from. m4 and m5 each independently represent preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and further preferably 0 or 1. R 4 is preferably a fluorine atom, a fluorinated alkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the fluorinated alkyl group and the alkyl group may be replaced by -O- or -CO-). R 5 is a fluorine atom, a fluorinated alkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the fluorinated alkyl group and the alkyl group may be replaced by -O- or -CO-), or -O-CO-C(R 1b )(R 2b )(R 3b ) is more preferable.

[0015] -O-CO-C(R 1a )(R 2a )(R 3a ) may be in the o-position, m-position, or p-position relative to the bonding position of the iodine atom, but the p-position is preferred. R 4 and R 5 The bonding position of may be any of the о-position, m-position, and p-position with respect to the bonding position of the iodine atom. 5 is -O-CO-C(R 1a )(R 2a )(R 3a ) is preferably bonded at the same position as

[0016] Examples of the cation (I) include the following cations: TIFF0007624807000009.tif164144

[0017] In formula (I), X 0Examples of the hydrocarbon group represented by the formula (I) include aliphatic hydrocarbon groups (chain hydrocarbon groups such as alkyl groups, alkenyl groups, and alkynyl groups, and alicyclic hydrocarbon groups), aromatic hydrocarbon groups, and groups combining these groups, etc. -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 9, further preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkenyl group include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octynyl, isooctynyl, and nonenyl groups. Examples of the alkynyl group include an ethynyl group, a propynyl group, an isopropynyl group, a butynyl group, an isobutynyl group, a tert-butynyl group, a pentynyl group, a hexynyl group, an octynyl group, and a nonynyl group. The alicyclic hydrocarbon group may be any of monocyclic, polycyclic and spirocyclic, and may be any of saturated and unsaturated. Examples of the alicyclic hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclononyl, cyclodecyl and cyclododecyl, and polycyclic cycloalkyl groups such as norbornyl and adamantyl. Specific examples of the alicyclic hydrocarbon group and the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. X 0The alicyclic hydrocarbon group represented by the formula (Y1) to (Y41) (* represents a bond position) is preferably a group represented by the formula (Y1) to (Y20), (Y26), (Y27), (Y30), (Y31), (Y39) to (Y41), more preferably a group represented by any one of the formulas (Y1) to (Y20), (Y26), (Y27), (Y30), (Y31), (Y39) to (Y41), and even more preferably a group represented by the formula (Y3), (Y4), (Y9), (Y11), (Y14), (Y15), (Y16), (Y20), (Y26), (Y27), (Y30), (Y31), (Y39) or (Y40). The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. TIFF0007624807000010.tif80155

[0018] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, a binaphthyl group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 36, more preferably 6 to 24, still more preferably 6 to 18, still more preferably 6 to 14, and still more preferably 6 to 10. In the case of a combined group, the above groups may contain groups having different valences (such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, a cycloalkanediyl group, a cycloalkanetriyl group, or a cycloalkanetetrayl group).

[0019] The combined groups are: a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-); A group combining an open chain hydrocarbon group and an aromatic hydrocarbon group (-CH2- contained in the open chain hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), and It represents a group formed by combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). In addition, in the combination, two or more types of each of the alicyclic hydrocarbon groups, the chain hydrocarbon groups and the aromatic hydrocarbon groups may be combined. Specifically, the combined groups are: Alicyclic hydrocarbon groups such as adamantylmethylene group and cyclohexylmethylene group-chain hydrocarbon group-*, (alicyclic hydrocarbon group)2-chain hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), Chain hydrocarbon group-alicyclic hydrocarbon group-* such as methyladamantyl group and dimethyladamantyl group, (chain hydrocarbon group)2-alicyclic hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), a chain hydrocarbon group such as a tolyl group or a xylyl group-aromatic hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-); Chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-* such as methylcyclohexylmethylene group, (chain hydrocarbon group)2-alicyclic hydrocarbon group-chain hydrocarbon group-*, (chain hydrocarbon group-alicyclic hydrocarbon group)2-chain hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), an aromatic hydrocarbon group such as a benzyl group-a chain hydrocarbon group-* (wherein the -CH2- contained in the chain hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-); A chain hydrocarbon group such as a tolylmethyl group-aromatic hydrocarbon group-chain hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-* such as methyladamantanemethyleneadamantyl group and di(methyladamantanemethylene)adamantyl group, (chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group)2-alicyclic hydrocarbon group-*, (chain hydrocarbon group-alicyclic hydrocarbon group)2-chain hydrocarbon group-alicyclic hydrocarbon group-*, (chain hydrocarbon group)2-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), Alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-*, (alicyclic hydrocarbon group)2-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-*, (alicyclic hydrocarbon group-chain hydrocarbon group)2-alicyclic hydrocarbon group-chain hydrocarbon group-*, (alicyclic hydrocarbon group-chain hydrocarbon group)2-alicyclic hydrocarbon group-chain hydrocarbon group-*, (alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group)2-chain hydrocarbon group-* (-CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), open chain hydrocarbon group-alicyclic hydrocarbon group-open chain hydrocarbon group-alicyclic hydrocarbon group-open chain hydrocarbon group-*, (open chain hydrocarbon group)2-alicyclic hydrocarbon group-open chain hydrocarbon group-alicyclic hydrocarbon group-open chain hydrocarbon group-*, (open chain hydrocarbon group-alicyclic hydrocarbon group)2-open chain hydrocarbon group-alicyclic hydrocarbon group-open chain hydrocarbon group-*, (open chain hydrocarbon group-alicyclic hydrocarbon group-open chain hydrocarbon group)2-alicyclic hydrocarbon group-open chain hydrocarbon group-*, (open chain hydrocarbon group-alicyclic hydrocarbon group-open chain hydrocarbon group-alicyclic hydrocarbon group)2-open chain hydrocarbon group-* (-CH2- contained in the open chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), Here, * indicates the bond position to the carbon atom of the carbonyl group.

[0020] X 0 When -CH2- in the hydrocarbon group represented by the formula (I) is replaced by -O-, -S-, -CO-, or -SO2-, the number of carbon atoms before the replacement is the total number of carbon atoms in the hydrocarbon group. 0When a substituent is bonded to a hydrocarbon group represented by the following formula (I), the number of carbon atoms before substitution is regarded as the total number of carbon atoms in the hydrocarbon group.

[0021] X 0 The hydrocarbon group represented by the following formula may 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 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a combination of these groups. 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 a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, and a nonyl group. 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, and a dodecyloxy group. 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 carbonyloxy group is bonded to the above-mentioned alkyl group or alkoxy group. Examples of the alkoxycarbonyl group having 2 to 13 carbon atoms include a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group having 2 to 13 carbon atoms include an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group having 2 to 13 carbon atoms include an acetyloxy group, a propionyloxy group, and a butyryloxy group. Examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include the groups shown below. ** represents X 0 represents the bonding position with TIFF0007624807000011.tif17162 Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include aryl groups such as a phenyl group and a naphthyl group. Examples of the combined group include a group in which a hydroxy group is combined with an alkyl group having 1 to 12 carbon atoms, a group in which an alkyl group having 1 to 12 carbon atoms is combined with an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a group in which an alicyclic hydrocarbon group having 3 to 12 carbon atoms is combined with an aromatic hydrocarbon group having 6 to 10 carbon atoms. Examples of the group combining a hydroxy group with 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 alkyl group having 1 to 12 carbon atoms with an aromatic hydrocarbon group having 6 to 10 carbon atoms include aralkyl groups having 7 to 22 carbon atoms, such as a benzyl group, and alkylaryl groups having 7 to 22 carbon atoms, such as a tolyl group and a xylyl group. Examples of the group formed by combining an alicyclic hydrocarbon group having 3 to 12 carbon atoms with an aromatic hydrocarbon group having 6 to 10 carbon atoms include a cyclohexylphenyl group.

[0022] X 0 The hydrocarbon group represented by the formula (aa) is preferably an aliphatic hydrocarbon group having 1 to 72 carbon atoms which may have a substituent (-CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, or a group represented by the formula (aa): More preferably, it is an alicyclic hydrocarbon group which may have a hydroxy group or a fluorine atom (wherein -CH- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO-), a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group (wherein -CH- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO-, and where -CH- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the alicyclic hydrocarbon group and the chain hydrocarbon group may have a fluorine atom or a hydroxy group), an aromatic hydrocarbon group which may have a fluorine atom or a hydroxy group, or a group represented by formula (aa), More preferably, *-alicyclic hydrocarbon group (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the alicyclic hydrocarbon group may have a hydroxyl group or a fluorine atom. * is -COO - represents a bonding position with a carbon atom of the formula (I), *-alicyclic hydrocarbon group-alkyl group (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the alkyl group may be replaced by -O- or -CO-, and the alicyclic hydrocarbon group and the alkyl group may have a fluorine atom or a hydroxyl group. * represents -COO - represents the bonding position with the carbon atom of More preferably, *-a polycyclic alicyclic hydrocarbon group (-CH2- contained in the polycyclic alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the polycyclic alicyclic hydrocarbon group may have a hydroxy group or a fluorine atom. * is -COO -represents a bonding position with a carbon atom of the formula (I), *-polycyclic alicyclic hydrocarbon group-alkyl group (-CH2- contained in the polycyclic alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the alkyl group may be replaced by -O- or -CO-, and the polycyclic alicyclic hydrocarbon group and the alkyl group may have a fluorine atom or a hydroxyl group. * represents -COO - represents the bonding position with the carbon atom of Particularly preferred are an adamantanone group, a hydroxyadamantyl group, a group combining an adamantyl group with an alkyl group (wherein the -CH2- contained in the alkyl group may be replaced with -O- or -CO-), a group represented by formula (Y30F), a phenyl group having a hydroxy group, or a group represented by formula (aa). In the above groups, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 12, more preferably 1 to 9, even more preferably 1 to 6, and even more preferably 1 to 4. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 36, more preferably 6 to 24, even more preferably 6 to 18, even more preferably 6 to 14, and even more preferably 6 to 10. TIFF0007624807000012.tif2666[In formula (aa), X a and X b each independently represents -O- or -S-. X 1 represents a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. X 2 represents a hydrocarbon group having 1 to 48 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. * indicates the bonding position with the carbon atom of the carbonyl group.

[0023] X a and X b are preferably the same atom, and more preferably both are oxygen atoms.

[0024] X 1 and X 2 Examples of the hydrocarbon group represented by the formula (1) include an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group in which two or more of these are combined. Note that -CH2- contained in these hydrocarbon groups may be replaced by -O-, -S-, -CO-, or -SO2-.

[0025] X 1 Examples of the aliphatic hydrocarbon group include chain hydrocarbon groups such as alkanetriyl groups, alicyclic hydrocarbon groups, and combinations thereof. Specific examples of the alkanetriyl group include a methine group, an ethanetriyl group, a propanetriyl group, a butanetriyl group, a pentanetriyl group, a hexanetriyl group, a heptanetriyl group, an octanetriyl group, a nonanetriyl group, a decanetriyl group, an undecanetriyl group, and a dodecanetriyl group.

[0026] The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclobutanetriyl group, a cyclopentanetriyl group, a cyclohexanetriyl group, and a cyclooctanetriyl group. Examples of the polycyclic alicyclic hydrocarbon group include a norbornanetriyl group, a norbornanetriyl group, and an adamantanetriyl group. Examples of the aromatic hydrocarbon group include a benzenetriyl group, a naphthalenetriyl group, and an anthracenetriyl group. In the case of a combination of groups, the above groups may contain groups having different valences (such as an alkyl group, an alkanediyl group, an alkanetetrayl group, a cycloalkyl group, a cycloalkanediyl group, or a cycloalkanetetrayl group).

[0027] X 1 The hydrocarbon group represented by the formula (I) has 1 to 24 carbon atoms and may further have one or more substituents. Examples of the substituents 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 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a combination of these groups. Examples of the halogen atom, alkyl group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combinations thereof include the same groups as described above.

[0028] X 1 The hydrocarbon group represented by the formula (i) is preferably an alkanetriyl group having 1 to 6 carbon atoms which may have a substituent or an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, more preferably an alkanetriyl group having 1 to 6 carbon atoms or a group represented by formula (w1-1) to formula (w1-11), and even more preferably an alkanetriyl group having 1 to 6 carbon atoms, a polycyclic hydrocarbon group such as an alkanetriyl group having 1 to 6 carbon atoms, a group represented by formula (w1-1) or a group represented by formula (w1-3), or a monocyclic hydrocarbon group such as a group represented by formula (w1-2) or a group represented by formula (w1-6). TIFF0007624807000013.tif62148 [Formula (w1-1) to formula (w1-11), The ring may have 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 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a combination of these groups. * represents a bond position. In formulae (w1-9) to (w1-11), the three bond positions can be any positions.]

[0029] X 2 The number of carbon atoms in the hydrocarbon group represented by the formula (I) is preferably 2 to 48, more preferably 4 to 48, even more preferably 6 to 44, still more preferably 8 to 40, and even more preferably 10 to 38. This hydrocarbon group may have a substituent. Furthermore, -CH2- contained in this hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Here, the number of carbon atoms in a hydrocarbon group means the number of carbon atoms in an unsubstituted or unsubstituted hydrocarbon group.

[0030] X 2 Examples of the substituent that the hydrocarbon group in the formula (I) may have 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 12 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a combination of these. Examples of the halogen atom, alkyl group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combinations thereof include the same groups as those mentioned above. X 2 The hydrocarbon group having 1 to 48 carbon atoms represented by the following formula may have one or more substituents.

[0031] X 2 Examples of the hydrocarbon group in include linear or branched chain hydrocarbon groups (e.g., alkanediyl groups, etc.), monocyclic or polycyclic alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may be a combination of two or more of these groups. Specific examples of such alkyl groups include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, and an octane-1,8-diyl group; branched alkanediyl groups such as ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic alicyclic hydrocarbon groups such as monocyclic cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl groups; polycyclic alicyclic hydrocarbon groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, and adamantane-2,6-diyl groups; Examples of the aromatic hydrocarbon groups include a phenylene group, a naphthylene group, a biphenylene group, an anthrylene group, a phenanthrylene group, and a binaphthylene group. In the case of a combination of groups, the above groups may contain groups having different valences (such as an alkyl group, an alkanetriyl group, an alkanetetrayl group, a cycloalkyl group, a cycloalkanetriyl group, or a cycloalkanetetrayl group). Examples of the combined group include a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are combined, a group in which a chain hydrocarbon group and an aromatic hydrocarbon group are combined, and a group in which an alicyclic hydrocarbon group and an aromatic hydrocarbon group are combined. Specific examples include a group in which one or more alicyclic hydrocarbon groups are bonded to a chain hydrocarbon group (e.g., -chain hydrocarbon group-alicyclic hydrocarbon group, -chain hydrocarbon group-(alicyclic hydrocarbon group)2, etc.), a group in which one or more chain hydrocarbon groups are bonded to an alicyclic hydrocarbon group (e.g., -alicyclic hydrocarbon group-chain hydrocarbon group, -alicyclic hydrocarbon group-(chain hydrocarbon group)2, etc.), a group in which one or more alicyclic hydrocarbon groups and chain hydrocarbon groups are bonded to a chain hydrocarbon group (e.g., -chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group, -chain hydrocarbon group-(alicyclic hydrocarbon group-chain hydrocarbon group)2, etc.).

[0032] X 2 As the hydrocarbon group in A chain hydrocarbon group having 2 to 18 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent), or It is preferably a group (which may have a substituent) combining a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-) and an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), A chain hydrocarbon group having 4 to 18 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent), or It is more preferable that the group is a combination of a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-) and an alicyclic hydrocarbon group having 3 to 16 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) (the group may have a substituent), A chain hydrocarbon group having 6 to 14 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent), or More preferred is a group (which may have a substituent) combining a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-) with an alicyclic hydrocarbon group having 5 to 14 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-).

[0033] Specifically, X 2 Examples of the hydrocarbon group in an alkanediyl group having 2 to 18 carbon atoms (-CH- contained in the alkanediyl group may be replaced by -O- or -CO-, and the alkanediyl group may have a substituent); a group consisting of an alkanediyl group having 1 to 12 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-) and an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) (the group may have a substituent); or It is preferably a group consisting of an alkanediyl group having 1 to 12 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced by -O- or -CO-) (the group may have a substituent), an alkanediyl group having 4 to 18 carbon atoms (-CH- contained in the alkanediyl group may be replaced by -O- or -CO-, and the alkanediyl group may have a substituent); a group consisting of an alkanediyl group having 1 to 12 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-) and an alicyclic hydrocarbon group having 3 to 16 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) (the group may have a substituent); or It is more preferable that the alkyl group is an alkanediyl group having 1 to 12 carbon atoms (-CH2- contained in the alkanediyl group may be replaced with -O- or -CO-), an alicyclic hydrocarbon group having 3 to 16 carbon atoms, and an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), which may have a substituent. an alkanediyl group having 6 to 14 carbon atoms (-CH- contained in the alkanediyl group may be replaced by -O- or -CO-, and the alkanediyl group may have a substituent); A group consisting of an alkanediyl group having 1 to 12 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-) and an adamantanediyl group (-CH2- contained in the adamantanediyl group may be replaced by -O- or -CO-) (the group may have a substituent), or More preferred are an alkanediyl group having 1 to 12 carbon atoms (-CH2- contained in the alkanediyl group may be replaced with -O- or -CO-) and a group consisting of an adamantanediyl group and an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-) (the group may have a substituent).

[0034] Specifically, X 2 is the formula (X 2 -1), a group represented by the formula (X 2 -2), a group represented by the formula (X 2 -3) or a group represented by the formula (X 2 -4) is preferred. TIFF0007624807000014.tif34158[In the formula, R 1x , R 2x , R 3x , R 4x , R 5x and R 6x each independently represents an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group combining two or more of these groups, and -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the alkyl group and the alicyclic hydrocarbon group may have a substituent. * is X a and X b represents the bond position with The combined group may be a combination of one each of the above-mentioned alkyl groups and alicyclic hydrocarbon groups, or a combination of two or more of either or both of them. In this case, the number of carbon atoms in the combined group is 39 or less, and preferably 37 or less.

[0035] Among them, R 1x , R 2x , R 3x , R 4x , R 5x and R 6x Examples of the alkyl group include an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-, and the alkyl group may have a substituent), an alicyclic hydrocarbon group having 5 to 12 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-, and the alicyclic hydrocarbon group may have a substituent), or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-) and an alicyclic hydrocarbon group having 5 to 12 carbon atoms (the alicyclic hydrocarbon group may have a substituent). and more preferably a methoxy group, an adamantyl group (-CH2- contained in the adamantyl group may be replaced by -O- or -CO-, and the adamantyl group may have a substituent), or a group combining an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced by -O- or -CO-) and an adamantyl group (this group may have a substituent).

[0036] Examples of the carboxylate anion in the carboxylate salt represented by formula (I) include the carboxylate anions described below. TIFF0007624807000015.tif98162

[0037] TIFF0007624807000016.tif119144

[0038] TIFF0007624807000017.tif125139

[0039] TIFF0007624807000018.tif122154

[0040] TIFF0007624807000019.tif115153

[0041] TIFF0007624807000020.tif41148

[0042] Specific examples of the carboxylate (I) include salts of any combination of the above-mentioned cations and anions. Specific examples of the carboxylate (I) are shown in the table below. In the following table, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation. For example, carboxylate (I-1) is a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (Ic-1), and is the salt shown below. TIFF0007624807000021.tif1796

[0043] [Table 1] TIFF0007624807000023.tif223160 TIFF0007624807000024.tif223160 TIFF0007624807000025.tif223160 TIFF0007624807000026.tif223160 TIFF0007624807000027.tif223160 TIFF0007624807000028.tif223160 TIFF0007624807000029.tif223160 TIFF0007624807000030.tif223160 TIFF0007624807000031.tif223160 TIFF0007624807000032.tif223160 TIFF0007624807000033.tif223160 TIFF0007624807000034.tif223160 TIFF0007624807000035.tif223160 TIFF0007624807000036.tif223160 TIFF0007624807000037.tif223160 TIFF0007624807000038.tif223160 TIFF0007624807000039.tif223160 TIFF0007624807000040.tif223160 TIFF0007624807000041.tif223160 TIFF0007624807000042.tif171162

[0044] Among them, the carboxylate (I) includes carboxylate (I-1) to carboxylate (I-5), carboxylate (I-55) to carboxylate (I-59), carboxylate (I-109) to carboxylate (I-113), carboxylate (I-163) to carboxylate (I-167), carboxylate (I-217) to carboxylate (I-221), carboxylate (I-271) to carboxylate (I-275), carboxylate (I-325) to carboxylate (I-329), and carboxylate (I-330). 79) to carboxylate (I-383), carboxylate (I-433) to carboxylate (I-437), carboxylate (I-487) to carboxylate (I-491), carboxylate (I-541) to carboxylate (I-545), carboxylate (I-595) to carboxylate (I-599), carboxylate (I-649) to carboxylate (I-653), carboxylate (I-703) to carboxylate (I-707), and carboxylate (I-757) to carboxylate (I-761) are preferred.

[0045] <Method for producing carboxylate (I)> The carboxylate (I) can be produced by reacting a salt represented by the formula (Ia) with a compound represented by the formula (Ib) in a solvent. TIFF0007624807000043.tif50161 [wherein all symbols have the same meanings as defined above. X represents a chlorine atom, a bromine atom or an iodine atom. R A , R B and R C each independently represents a hydrocarbon group having 1 to 12 carbon atoms, or R A , R B and R C may combine together to form an aromatic ring. D represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.] Examples of the solvent used in this reaction include chloroform, acetonitrile, and ion-exchanged water. The reaction temperature is usually 0° C. to 80° C., and the reaction time is usually 0.5 hours to 24 hours.

[0046] The salt represented by formula (Ib) can be synthesized with reference to the methods described in JP-A-2011-39502 and JP-A-2014-88367, and examples thereof include salts represented by the following formula (Ib). TIFF0007624807000044.tif145156

[0047] The salt represented by formula (Ia) can be produced by reacting a compound represented by formula (Ic) with a salt represented by formula (Id) in a solvent in the presence of a catalyst. TIFF0007624807000045.tif46135 [wherein all symbols have the same meanings as defined above.] Catalysts include potassium peroxymonosulfate (Oxone®), sulfuric acid, p-toluenesulfonic acid, and the like. Examples of the solvent include chloroform, monochlorobenzene, and acetonitrile. The reaction temperature is usually from 0° C. to 80° C., and the reaction time is usually from 0.5 to 24 hours.

[0048] Examples of the compound represented by formula (Ic) include compounds represented by the following formula, which are readily available on the market and can be easily produced by known methods. TIFF0007624807000046.tif48139

[0049] Examples of the compound represented by formula (Id) include compounds represented by the following formula, and are readily available on the market. TIFF0007624807000047.tif1417

[0050] The salt represented by the following formula (I-a1) can be produced by reacting a compound represented by formula (Ie) with potassium iodate in a solvent in the presence of sulfuric acid, and then mixing the resulting mixture with sodium bromide. TIFF0007624807000048.tif47140 [wherein all symbols have the same meanings as defined above.] Examples of the solvent include acetic acid, acetic anhydride, chloroform, monochlorobenzene, and acetonitrile. The reaction temperature is usually from 0° C. to 80° C., and the reaction time is usually from 0.5 to 24 hours.

[0051] Examples of the compound represented by formula (Ie) include compounds represented by the following formulas, which are readily available on the market and can be easily produced by known methods. TIFF0007624807000049.tif46135

[0052] [Acid Generator] The acid generator of the present invention is an acid generator containing a carboxylate (I). The carboxylate (I) of the present invention can act as an acid generator in a resist composition. When the carboxylate (I) is used as an acid generator in a resist composition, the acid generator may contain only one type or two or more types of the carboxylate (I). As described below, the acid generator of the present invention may further contain an acid generator other than the carboxylate (I) that is known in the resist field (hereinafter, may be referred to as "acid generator (B)") and / or a carboxylic acid generator other than the carboxylate (I) that is known in the resist field. The acid generator (B) and the like may be used alone or in combination of two or more kinds. When the acid generator of the present invention contains an acid generator (B) or the like, the content ratio of the carboxylate (I) to the acid generator (B) (mass ratio; carboxylate (I):acid generator (B), etc.) is usually 1:99 to 100:0, preferably 1:99 to 99:1, more preferably 2:98 to 98:2, and even more preferably 5:95 to 95:5.

[0053] [Resist Composition] The resist composition contains a carboxylic acid generator containing the carboxylate (I) of the present invention, an acid generator (B) other than the carboxylate (I), and a resin having an acid labile group (hereinafter sometimes referred to as "resin (A)"). The "acid labile group" here means a group that has a leaving group and that is released by contact with an acid to form a hydrophilic group (e.g., a hydroxy group or a carboxy group). The resist composition preferably further contains a quencher (hereinafter sometimes referred to as “quencher (C)”) and / or a solvent (hereinafter sometimes referred to as “solvent (E)”).

[0054] <Acid Generator (B)> The acid generator (B) may be either nonionic or ionic. Examples of nonionic acid generators include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), etc. Examples of ionic acid generators include onium salts containing onium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of anions of onium salts include sulfonate anion, sulfonylimide anion, sulfonylmethide anion, etc.

[0055] As the acid generator (B), compounds that generate acid by radiation, such as those described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Pat. No. 3,779,778, U.S. Pat. No. 3,849,137, German Patent No. 3914407, and European Patent No. 126,712, can be used. Compounds produced by known methods can also be used. Two or more types of acid generators (B) can be used in combination.

[0056] The acid generator (B) is preferably a fluorine-containing acid generator, and more preferably a salt represented by formula (B1) (hereinafter sometimes referred to as "acid generator (B1)"). TIFF0007624807000050.tif2962[In formula (B1), Q b1 and Q b2 each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. L b1 represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, in which -CH2- may be replaced by -O- or -CO-, and a hydrogen atom 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 18 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S(O)2- or -CO-. Z + represents an organic cation.

[0057] Q b1 and Q b2 Examples of the perfluoroalkyl group represented by the formula (I) include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Q b1 and Q b2 and are preferably each independently a fluorine atom or a trifluoromethyl group, and more preferably both are fluorine atoms.

[0058] L b1 Examples of the divalent saturated hydrocarbon group in include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and may be a group formed by combining two or more of these groups. Specific examples of such straight-chain alkanediyl groups include methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl groups; branched alkanediyl groups such as ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; Examples of the polycyclic divalent alicyclic saturated hydrocarbon groups include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group.

[0059] L b1 Examples of the divalent saturated hydrocarbon group in which -CH2- is replaced with -O- or -CO- include groups represented by formulae (b1-1) to (b1-3). In the groups represented by formulae (b1-1) to (b1-3) and specific examples thereof, such as the groups represented by formulae (b1-4) to (b1-11), * and ** represent bonding positions, and * represents bonding position with -Y.

[0060] TIFF0007624807000051.tif26117 [In formula (b1-1), L b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b2 and L b3 The total number of carbon atoms is 22 or less. In formula (b1-2), L b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b4 and L b5 The total number of carbon atoms is 22 or less. In formula (b1-3), L b6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. L b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the saturated hydrocarbon group may be substituted with -O- or -CO-. However, L b6 and L b7 The total number of carbon atoms is 23 or less.

[0061] In the groups represented by formulae (b1-1) to (b1-3), when -CH2- contained in the saturated hydrocarbon group is replaced with -O- or -CO-, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the saturated hydrocarbon group. As the divalent saturated hydrocarbon group, L b1 The divalent saturated hydrocarbon group may be the same as that of the above.

[0062] L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom. L b5 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b6 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b7 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, and -CH2- contained in the divalent saturated hydrocarbon group may be substituted with -O- or -CO-.

[0063] L b1 As the divalent saturated hydrocarbon group represented by the formula (b1-1) or (b1-3), a group in which --CH2-- in the divalent saturated hydrocarbon group represented by the formula (b1-1) or (b1-3) is preferable.

[0064] Examples of the group represented by formula (b1-1) include the groups represented by formulas (b1-4) to (b1-8). TIFF0007624807000052.tif48120[In formula (b1-4), L b8 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. In formula (b1-5), L b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-. L b10 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b9 and Lb10 The total number of carbon atoms is 20 or less. In formula (b1-6), L b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b11 and L b12 The total number of carbon atoms is 21 or less. In formula (b1-7), L b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. L b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced with -O- or -CO-. L b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group. However, L b13 ~L b15 The total number of carbon atoms is 19 or less. In formula (b1-8), L b16 represents 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 with a fluorine atom or a hydroxy group. However, L b16 ~L b18 The total number of carbon atoms is 19 or less.

[0065] L b8is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0066] Examples of the group represented by formula (b1-3) include the groups represented by formulas (b1-9) to (b1-11). TIFF0007624807000053.tif23140[In formula (b1-9), L b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b20represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxyl group or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxyl group. However, L b19 and L b20 The total number of carbon atoms is 23 or less. In formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxyl group or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxyl group. However, L b21 , L b22 and L b23 The total number of carbon atoms is 21 or less. In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxyl group or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxyl group. However, L b24 , L b25 and L b26 The total number of carbon atoms is 21 or less.

[0067] In addition, in the groups represented by formulae (b1-9) to (b1-11), when a hydrogen atom contained in the saturated hydrocarbon group is substituted with an alkylcarbonyloxy group, the number of carbon atoms before substitution is regarded as the number of carbon atoms of the saturated hydrocarbon group.

[0068] Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, and an adamantylcarbonyloxy group.

[0069] Examples of the group represented by formula (b1-4) include the following. TIFF0007624807000054.tif16154

[0070] Examples of the group represented by formula (b1-5) include the following. TIFF0007624807000055.tif68152

[0071] Examples of the group represented by formula (b1-6) include the following. TIFF0007624807000056.tif32164

[0072] Examples of the group represented by formula (b1-7) include the following. TIFF0007624807000057.tif57146

[0073] Examples of the group represented by formula (b1-8) include the following. TIFF0007624807000058.tif23150

[0074] Examples of the group represented by formula (b1-2) include the following. TIFF0007624807000059.tif31161

[0075] Examples of the group represented by formula (b1-9) include the following. TIFF0007624807000060.tif44137

[0076] Examples of the group represented by formula (b1-10) include the following. TIFF0007624807000061.tif92165

[0077] Examples of the group represented by formula (b1-11) include the following. TIFF0007624807000062.tif84164

[0078] The alicyclic hydrocarbon group represented by Y is, for example, X in formula (I). 0 Examples of the groups include the groups represented by the above formulae (Y1) to (Y11) and (Y36) to (Y38). When -CH2- contained in the alicyclic hydrocarbon group represented by Y is replaced by -O-, -S(O)2- or -CO-, the number may be 1 or may be 2 or more. Examples of such a group include groups represented by formulae (Y12) to (Y35) and formulae (Y39) to (Y41).

[0079] The alicyclic hydrocarbon group represented by Y is preferably a group represented by any one of the formulae (Y1) to (Y20), (Y26), (Y27), (Y30), (Y31), (Y39) to (Y41), more preferably a group represented by the formula (Y11), (Y15), (Y16), (Y20), (Y26), (Y27), (Y30), (Y31), (Y39) or (Y40), and even more preferably a group represented by the formula (Y11), (Y15), (Y20), (Y26), (Y27), (Y30), (Y31), (Y39) or (Y40). When the alicyclic hydrocarbon group represented by Y is a spiro ring containing an oxygen atom such as those of formulae (Y28) to (Y35) and (Y39) to (Y40), the alkanediyl group between the two oxygen atoms preferably has one or more fluorine atoms. In addition, among the alkanediyl groups contained in the ketal structure, it is preferable that the methylene group adjacent to the oxygen atom is not substituted with a fluorine atom.

[0080] The substituent of the methyl group represented by Y is a halogen atom, a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-OR b1 Group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2- or -CO-, and a hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. ja represents an integer of 0 to 4.) Substituents of the alicyclic hydrocarbon group represented by Y include a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms which may be substituted with a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-OR b1 Group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, -CH2- contained in the alkyl group and the alicyclic hydrocarbon group may be replaced by -O-, -SO2- or -CO-, and a hydrogen atom contained in the alkyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be replaced by a hydroxy group or a fluorine atom. ja represents an integer of 0 to 4.)

[0081] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a norbornyl group, and an adamantyl group. 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, and examples of the aromatic hydrocarbon group having a chain hydrocarbon group with 1 to 18 carbon atoms include a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group, and examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group with 3 to 18 carbon atoms include a p-cyclohexylphenyl group and a p-adamantylphenyl group. 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. 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 alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group.

[0082] Y includes the following: TIFF0007624807000063.tif151153

[0083] Y is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, more preferably an adamantyl group which may have a substituent, and -CH2- constituting the alicyclic hydrocarbon group or the adamantyl group may be replaced by -CO-, -S(O)2- or -CO-. Y is more preferably an adamantyl group, a hydroxyadamantyl group, an oxoadamantyl group or a group represented by the following formula: TIFF0007624807000064.tif60162

[0084] The anion in the salt represented by formula (B1) is preferably an anion represented by formula (B1-A-1) to formula (B1-A-55) (hereinafter, may be referred to as "anion (B1-A-1)" depending on the formula number), and more preferably an anion represented by any of formula (B1-A-1) to formula (B1-A-4), (B1-A-9), (B1-A-10), (B1-A-24) to formula (B1-A-33), (B1-A-36) to formula (B1-A-40), and (B1-A-47) to formula (B1-A-55).

[0085] TIFF0007624807000065.tif111143

[0086] TIFF0007624807000066.tif128166

[0087] TIFF0007624807000067.tif93145

[0088] TIFF0007624807000068.tif126140

[0089] TIFF0007624807000069.tif114154 Here R i2 ~R i7 are each independently, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. i8 L is, for example, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. A4 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 has the same meaning as above. Specific examples of the anion in the salt represented by formula (B1) include the anions described in JP-A-2010-204646.

[0090] Preferred anions in the salt represented by formula (B1) include the anions represented by formulas (B1a-1) to (B1a-34). TIFF0007624807000070.tif193158

[0091] TIFF0007624807000071.tif185163

[0092] Among these, anions represented by any one of Formulae (B1a-1) to (B1a-3), (B1a-7) to (B1a-16), (B1a-18), (B1a-19), and (B1a-22) to (B1a-30) are preferred.

[0093] Z1 + Examples of the organic cation include organic onium cation, organic sulfonium cation, organic iodonium cation, organic ammonium cation, benzothiazolium cation, and organic phosphonium cation. Among these, organic sulfonium cation and organic iodonium cation are preferred, and arylsulfonium cation is more preferred. Specific examples include cations represented by any of formulas (b2-1) to (b2-4) (hereinafter, sometimes referred to as "cation (b2-1)" depending on the formula number). TIFF0007624807000072.tif77115In equations (b2-1) to (b2-4), R b4 ~R b6each independently represent a chain hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, a hydrogen atom contained in the chain hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, 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 hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of 0 to 5. When m2 is 2 or more, multiple R b7 may be the same or different, and when n2 is 2 or more, multiple R b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 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 b12represents an open 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, a hydrogen atom contained in the open chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including the -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 each independently represents a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. L b31 represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of 0 to 5. q2 and r2 each independently represent an integer of 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, multiple R b13 are the same or different, and when p2 is 2 or more, multiple R b14 are the same or different, and when q2 is 2 or more, multiple R b15 are the same or different, and when r2 is 2 or more, multiple R b16 are the same or different, and when s2 is 2 or more, multiple R b17 are the same or different, and when t2 is 2 or more, multiple R b18 are the same or different. The aliphatic hydrocarbon group refers to a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. In particular, R b9 ~R b12The chain hydrocarbon group preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups: TIFF0007624807000073.tif10159 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, and more preferably has 4 to 12 carbon atoms. Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methylnorbornyl group, an isobornyl group, etc. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms in the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain-type hydrocarbon group or an alicyclic hydrocarbon group. Examples of the aromatic hydrocarbon group having a chain-type 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. In addition, when the aromatic hydrocarbon group has a chain-type hydrocarbon group or an alicyclic hydrocarbon group, a chain-type hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. An example of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group is a p-methoxyphenyl group. Examples of the chain hydrocarbon group in which a hydrogen atom has been substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, and a 2-ethylhexylcarbonyloxy group. R b4 and R b5 The ring formed by bonding to each other together with the sulfur atom to which they are bonded may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include rings having 3 to 18 carbon atoms, and preferably rings having 4 to 18 carbon atoms. Examples of the ring containing a sulfur atom include 3-membered to 12-membered rings, and preferably 3-membered to 7-membered rings, and examples of such rings include the following rings. * represents a bonding position. TIFF0007624807000074.tif23144R b9 and R b10 The ring formed by these together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring may be a 3-membered to 12-membered ring, preferably a 3-membered to 7-membered ring. For example, it may be a thiolane-1-ium ring (tetrahydrothiophenium ring), a thiane-1-ium ring, a 1,4-oxathiane-4-ium ring, etc. R b11 and Rb12 The ring formed by combining with may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. The ring may be a 3-membered to 12-membered ring, preferably a 3-membered to 7-membered ring. Examples of the ring include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

[0094] Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferred. Examples of the cation (b2-1) include the following cations. TIFF0007624807000075.tif79158

[0095] TIFF0007624807000076.tif74143

[0096] Examples of the cation (b2-2) include the following cations. TIFF0007624807000077.tif18127

[0097] Examples of the cation (b2-3) include the following cations. TIFF0007624807000078.tif26140

[0098] Examples of the cation (b2-4) include the following cations. TIFF0007624807000079.tif134147

[0099] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, which can be combined arbitrarily. The acid generator (B) is preferably a combination of an anion represented by any one of formulas (B1a-1) to (B1a-3), (B1a-7) to (B1a-16), (B1a-18), (B1a-19), and (B1a-22) to (B1a-34) and a cation (b2-1) or a cation (b2-3).

[0100] The acid generator (B) is preferably one represented by formula (B1-1) to formula (B1-48). Among them, those containing an arylsulfonium cation are preferred, and those represented by formula (B1-1) to formula (B1-3), formula (B1-5) to formula (B1-7), formula (B1-11) to formula (B1-14), formula (B1-20) to formula (B1-26), formula (B1-29), and formula (B1-31) to formula (B1-48) are particularly preferred. TIFF0007624807000080.tif119149

[0101] JPEG0007624807000081.jpg77147

[0102] JPEG0007624807000082.jpg147147

[0103] JPEG0007624807000083.jpg61154

[0104] TIFF0007624807000084.tif107143

[0105] In the resist composition of the present invention, the content of the carboxylate (I) is preferably from 0.1 to 35% by mass, more preferably from 0.5 to 30% by mass, and even more preferably from 1 to 25% by mass, relative to the solid content of the resist composition. In addition, when an acid generator (B) or the like is contained, the total content of the carboxylate (I) and the acid generator (B) or the like is preferably 1 part by mass or more (more preferably 3 parts by mass or more) and preferably 55 parts by mass or less (more preferably 50 parts by mass or less, and even more preferably 45 parts by mass or less) relative to 100 parts by mass of the resin (A).

[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 the structural unit (a1). Examples of structural units other than the structural unit (a1) include a structural unit not having an acid labile group (hereinafter, sometimes referred to as "structural unit (s)"), structural units other than the structural unit (a1) and the structural unit (s) (for example, a structural unit having a halogen atom (hereinafter, sometimes referred to as "structural unit (a4)") described below, a structural unit having a non-leaving hydrocarbon group (hereinafter, sometimes referred to as "structural unit (a5)") described below, and other structural units derived from monomers known in the art.

[0107] <Structural unit (a1)> The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid labile group contained in the resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF0007624807000085.tif2397 [In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a combination thereof, or R a1 and R a2 are bonded to each other to form, together with the carbon atom to which they are bonded, an alicyclic hydrocarbon group having 3 to 20 carbon atoms. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * indicates the bond position.] TIFF0007624807000086.tif2379 [In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’are bonded to each other to form a heterocycle having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, and -CH2- contained in the hydrocarbon group and the heterocycle may be replaced by -O- or -S-. X represents an oxygen atom or a sulfur atom. na′ represents 0 or 1. * denotes a binding site.]

[0108] R a1 , R a2 and R a3 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site). R a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms. TIFF0007624807000087.tif10150 Examples of the group formed by combining an alkyl group with an alicyclic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, and a norbornylethyl group. Preferably, ma is 0 and na is 1. R a1 and R a2 When they are bonded to each other to form a non-aromatic hydrocarbon ring, -C(R a1 )(R a2 )(R a3 ) includes the following rings. The non-aromatic hydrocarbon ring preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-. TIFF0007624807000088.tif31135

[0109] R a1’ , R a2’ and R a3’ Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. The alkyl group and the alicyclic hydrocarbon group are R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group combining the above-mentioned alkyl group and an alicyclic hydrocarbon group (for example, a cycloalkylalkyl group), an aralkyl group such as a 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.), and an aryl-cycloalkyl group such as a phenylcyclohexyl group. R a1’ and R a2’ When they are bonded to each other to form a heterocycle together with the carbon atom to which they are attached and X, -C(R a1’ )(R a2’ )-XR a3’ Examples of the ring include the following: * represents a binding site. TIFF0007624807000089.tif21142R a1’ and R a2’ At least one of these is preferably a hydrogen atom. na' is preferably 0.

[0110] Examples of the group (1) include the following groups. In formula (1), R a1, R a2 and R a3 is an alkyl group, ma = 0, and na = 1. As the group, a tert-butoxycarbonyl group is preferable. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, R a3 is an alkyl group, ma=0, and na=1. In formula (1), R a1 and R a2 are each independently an alkyl group; R a3 is an adamantyl group, ma=0, and na=1. Specific examples of the group (1) include the following groups: * represents a binding site. TIFF0007624807000090.tif78168

[0111] Specific examples of the group (2) include the following groups. * represents the bonding position. TIFF0007624807000091.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] Of the (meth)acrylic monomers having an acid labile group, preferred are those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms. By using a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group in a resist composition, the resolution of the resist pattern can be improved.

[0114] Examples of the structural unit derived from the (meth)acrylic monomer having the group (1) include a structural unit represented by formula (a1-0) (hereinafter, sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter, sometimes referred to as structural unit (a1-2)). Preferably, 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. TIFF0007624807000092.tif41136 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 each independently represents -O- or * -O-(CH2) k1 represents --CO--O--, k1 represents an integer of 1 to 7, and * represents the bonding position with --CO--. R a01 , R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a02 , R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a combination thereof. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

[0115] R a01 , R a4 and R a5 is preferably a methyl group. L a01 , La1 and L a2 is preferably an oxygen atom or *-O-(CH2) k01 It is -CO-O- (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a77 The alkyl group, alicyclic hydrocarbon group and combination thereof in the formula (1) are R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a02 , R a03 , and R a04 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a6 and R a7 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, or an isopropyl group, and even more preferably an ethyl group or an isopropyl group. R a02 , R a03 and R a04 The alicyclic hydrocarbon group preferably has 5 to 12 carbon atoms, and more preferably 5 to 10 carbon atoms. In the group in which an alkyl group and an alicyclic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the alicyclic hydrocarbon group is preferably 18 or less. R a02 and R a03 is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group or an ethyl group. R a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, and more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. R a6 and R a7is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, or an isopropyl group, and even more preferably an ethyl group or an isopropyl group. m1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1' is preferably 0 or 1.

[0116] Examples of the structural unit (a1-0) include a structural unit represented by any one of formulas (a1-0-1) to (a1-0-12) and R a01 and structural units in which a methyl group corresponding to the following formula is replaced with a hydrogen atom. Of these, structural units represented by any one of formulae (a1-0-1) to (a1-0-10) are preferred. TIFF0007624807000093.tif66158

[0117] Examples of the structural unit (a1-1) include structural units derived from monomers described in JP 2010-204646 A. Among them, structural units represented by any one of formulas (a1-1-1) to (a1-1-4) and R in the structural unit (a1-1) are a4 In the above formula (a1-1-1), a structural unit in which a methyl group is replaced with a hydrogen atom is preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF0007624807000094.tif44114

[0118] The structural unit (a1-2) includes a structural unit represented by any one of formulas (a1-2-1) to (a1-2-6) and R a5 and structural units in which a methyl group corresponding to the formula (a1-2-2), (a1-2-5) or (a1-2-6) is replaced with a hydrogen atom are preferred. TIFF0007624807000095.tif36161

[0119] When the resin (A) contains the structural unit (a1-0), the content thereof is usually 5 to 60 mol %, preferably 5 to 50 mol %, and more preferably 10 to 40 mol %, based on all structural units in the resin (A). When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is usually 10 to 95 mol %, preferably 15 to 85 mol %, more preferably 15 to 80 mol %, even more preferably 20 to 80 mol %, and still more preferably 20 to 75 mol %, based on all structural units in the resin (A).

[0120] An example of the structural unit (a1) having a group (2) is a structural unit represented by formula (a1-4) (hereinafter, sometimes referred to as "structural unit (a1-4)"). TIFF0007624807000096.tif3867[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 alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. la represents an integer of 0 to 4. When la is 2 or more, a plurality of R a33 may be the same or different from each other. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -CO- to which they are bonded, and the -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 alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a 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 further preferably a methyl group. R a32 and R a33 Examples of the halogen atom in include a fluorine atom, a chlorine atom, and a bromine atom. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom 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. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, and a hexyloxy group. Among these, an alkoxy group having 1 to 4 carbon atoms is preferred, a methoxy group or an ethoxy group is more preferred, and a methoxy group is even more preferred. Alkylcarbonyl groups include acetyl, propionyl and butyryl groups. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. 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 consisting of a combination thereof. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): TIFF0007624807000097.tif10151 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group combining the above-mentioned alkyl group and alicyclic hydrocarbon group (e.g., 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. In particular, R a36 Examples of the alkyl group include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these groups.

[0122] In formula (a1-4), R a32 is preferably a hydrogen atom. R a33 As the alkyl group, an alkoxy group having 1 to 4 carbon atoms is preferable, a methoxy group and an ethoxy group are more preferable, and a methoxy group is even more preferable. la is preferably 0 or 1, and more preferably 0. R a34 is preferably a hydrogen atom. R a35 is preferably an alkyl group or an alicyclic hydrocarbon group having 1 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a36The hydrocarbon group in R is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. a36 The alkyl group and the alicyclic hydrocarbon group in R are preferably unsubstituted. a36 The aromatic hydrocarbon group in is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0123] -OC(R a34 )(R a35 )-OR a36 is eliminated on contact with an acid (e.g., p-toluenesulfonic acid) to form a hydroxy group. Examples of the structural unit (a1-4) include structural units derived from monomers described in JP 2010-204646 A. Preferred are the structural units represented by formulae (a1-4-1) to (a1-4-12) and R a32 and more preferably, the structural units represented by formulae (a1-4-1) to (a1-4-5) and (a1-4-10) are included. TIFF0007624807000098.tif68157 When resin (A) has structural unit (a1-4), the content thereof is preferably 5 to 60 mol %, more preferably 5 to 50 mol %, and even more preferably 10 to 40 mol %, based on the total of all structural units in resin (A).

[0124] An example of a structural unit derived from a (meth)acrylic monomer having the group (2) is a structural unit represented by formula (a1-5) (hereinafter, may be referred to as "structural unit (a1-5)"). TIFF0007624807000099.tif4354 formula (a1-5), R a8represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. Z a1 is a single bond or -(CH2) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 represents the bonding position with L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-. s1 represents an integer of 1 to 3. s1' represents an integer of 0 to 3.

[0125] Examples of the halogen atom include a fluorine atom and a chlorine atom, with a fluorine atom being preferred. Examples of the alkyl group having 1 to 6 carbon atoms 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 Of these, it is preferred that one is -O- and the other is -S-. It is preferable that s1 is 1. s1' is preferably an integer of 0 to 2. Z a1 is preferably a single bond or -CH2-CO-O-.

[0126] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP 2010-61117 A. Among them, the structural units represented by formulae (a1-5-1) to (a1-5-4) are preferred, and the structural unit represented by formula (a1-5-1) or (a1-5-2) is more preferred. TIFF0007624807000100.tif34138 When resin (A) has the structural unit (a1-5), the content thereof is preferably 1 to 50 mol %, more preferably 3 to 45 mol %, even more preferably 5 to 40 mol %, and even more preferably 5 to 30 mol %, based on all structural units of resin (A).

[0127] Examples of the structural unit (a1) include a structural unit represented by the formula (a1-0X) (hereinafter, sometimes referred to as a structural unit (a1-0X)). TIFF0007624807000101.tif3961[In formula (a1-0X), R x1 represents a hydrogen atom or a methyl group. R x2 and R x3 each independently represents a saturated hydrocarbon group having 1 to 6 carbon atoms. Ar x1 represents an aromatic hydrocarbon group having 6 to 36 carbon atoms.]

[0128] R x2 and R x3 The saturated hydrocarbon group includes an alkyl group, an alicyclic hydrocarbon group, and a group formed by combining these groups. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Ar x1 Examples of the aromatic hydrocarbon group include aryl groups having 6 to 36 carbon atoms, such as a phenyl group, a naphthyl group, and anthryl group. The aromatic hydrocarbon group preferably has 6 to 24 carbon atoms, more preferably has 6 to 18 carbon atoms, and is further preferably a phenyl group. Ar x1is preferably an aromatic hydrocarbon group having 6 to 18 carbon atoms, more preferably a phenyl group or a naphthyl group, and even more preferably a phenyl group. R x1 , R x2 and R x3 are each independently preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0129] The structural unit (a1-0X) includes the structural units shown below and R in the structural unit (a1-0X). x1 In the present invention, the structural unit (a1-0X) is preferably a compound in which a methyl group corresponding to the following formula is replaced with a hydrogen atom: The structural unit (a1-0X) is preferably a structural unit (a1-0X-1) to a structural unit (a1-0X-3). TIFF0007624807000102.tif34161 When the resin (A) has the structural unit (a1-0X), the content thereof is preferably 5 to 60 mol %, more preferably 5 to 50 mol %, and even more preferably 10 to 40 mol %, based on all monomers in the resin (A). The resin (A) may contain two or more types of the structural unit (a1-0X).

[0130] Further, examples of the structural unit (a1) include the following structural units. TIFF0007624807000103.tif27160 When the resin (A) contains the above structural unit, the content thereof is preferably from 5 to 60 mol %, more preferably from 5 to 50 mol %, and even more preferably from 10 to 40 mol %, based on the total structural units of the resin (A).

[0131] Structural unit(s) The structural unit (s) is derived from a monomer having no acid labile group (hereinafter, may be referred to as "monomer (s)"). As the monomer from which the structural unit (s) is derived, a monomer having no acid labile group known in the resist field can be used. The structural unit (s) preferably has a hydroxy group or a lactone ring. The use of 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 can improve the resolution of the resist pattern and the adhesion to the substrate.

[0132] <Structural unit (a2)> The hydroxy group contained in the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group. When a resist pattern is produced from the resist composition of the present invention, when a high energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) is used as an exposure light source, the structural unit (a2) having a phenolic hydroxyl group is preferable, and the structural unit (a2-A) described below is more preferable. When an ArF excimer laser (193 nm) or the like is used, the structural unit (a2) having an alcoholic hydroxyl group is preferable, and the structural unit (a2-1) described below is more preferable. The structural unit (a2) may contain one type alone or two or more types.

[0133] In the structural unit (a2), an example of a structural unit having a phenolic hydroxy group is a structural unit represented by formula (a2-A) (hereinafter, may be referred to as "structural unit (a2-A)"). TIFF0007624807000104.tif4146[In formula (a2-A), R a50 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a50 is a single bond or *-X a51 -(A a52 -X a52 ) nb - stands for -R. a50 represents the bond position with respect to the carbon atom to which it is bonded. A a52 each independently represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O-, or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, a plurality of R a51 may be the same or different.]

[0134] R a50 Examples of the halogen atom in include a fluorine atom, a chlorine atom, and a bromine atom. R a50 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, and a perfluorohexyl group. R 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 further preferably a hydrogen atom or a methyl group. R a51 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a51Examples of the alkoxy group in include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. An alkoxy group having 1 to 4 carbon atoms is preferred, a methoxy group or an ethoxy group is more preferred, and a methoxy group is even more preferred. R a51 Examples of the alkylcarbonyl group in the formula (I) include an acetyl group, a propionyl group, and a butyryl group. R a51 The alkylcarbonyloxy group in the above formula includes an acetyloxy group, a propionyloxy group, and a butyryloxy group. R a51 is preferably a methyl group.

[0135] *-X a51 -(A a52 -X a52 ) nb - includes *-O-, *-CO-O-, *-O-CO-, *-CO-OA a52 -CO-O-, *-O-CO-A a52 -O-, *-OA a52 -CO-O-, *-CO-OA a52 -O-CO-, *-O-CO-A a52 -O-CO-, and *-CO-O- and *-CO-OA are particularly well known. a52 -CO-O- or *-OA a52 -CO-O- is preferred. 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. A a50 is a single bond, *-CO-O- or *-CO-OA a52-CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. mb is preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0. The hydroxy group is preferably bonded to the ortho- or para-position of the benzene ring, and more preferably to the para-position.

[0136] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. The structural unit (a2-A) includes structural units represented by formulae (a2-2-1) to (a2-2-6) and R in the structural unit (a2-A) in the structural units represented by formulae (a2-2-1) to (a2-2-6). a50 The structural unit (a2-A) is a structural unit represented by formula (a2-2-1), a structural unit represented by formula (a2-2-3), a structural unit represented by formula (a2-2-6), and a structural unit represented by formula (a2-2-1), a structural unit represented by formula (a2-2-3), or a structural unit represented by formula (a2-2-6), in which R in the structural unit (a2-A) is substituted with a hydrogen atom. a50 It is preferable that the structural unit is a structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom. TIFF0007624807000105.tif42166 When the structural unit (a2-A) is contained in the resin (A), the content of the structural unit (a2-A) is preferably 5 to 80 mol %, more preferably 10 to 70 mol %, even more preferably 15 to 65 mol %, and still more preferably 20 to 65 mol %, based on all structural units. The structural unit (a2-A) can be incorporated into the resin (A) by, for example, polymerizing the structural unit (a1-4) and then treating with an acid such as p-toluenesulfonic acid. Alternatively, the structural unit (a2-A) can be incorporated into the resin (A) by polymerizing the structural unit (a1-4) and then treating with an alkali such as tetramethylammonium hydroxide.

[0137] An example of the structural unit (a2) having an alcoholic hydroxy group is a structural unit represented by formula (a2-1) (hereinafter sometimes referred to as "structural unit (a2-1)"). TIFF0007624807000106.tif4058 formula (a2-1), L a3 is -O- or * -O-(CH2) k2 represents -CO-O-, k2 represents an integer of any one of 1 to 7. * represents the bonding position with -CO-. R a14 represents a hydrogen atom or a methyl group. R a15 and R a16 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. o1 represents an integer of 0 to 10.

[0138] In formula (a2-1), L a3 is preferably -O-, -O-(CH2) f1 It is -CO-O- (wherein f1 represents an integer of 1 to 4), and more preferably -O-. R a14 is preferably a methyl group. R a15 is preferably a hydrogen atom. R a16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of 0 to 3, and more preferably 0 or 1.

[0139] Examples of the structural unit (a2-1) include structural units derived from monomers described in JP 2010-204646 A. A structural unit represented by any one of formulas (a2-1-1) to (a2-1-6) is preferred, a structural unit represented by any one of formulas (a2-1-1) to (a2-1-4) is more preferred, and a structural unit represented by formula (a2-1-1) or formula (a2-1-3) is even more preferred. TIFF0007624807000107.tif49138 When resin (A) contains the structural unit (a2-1), the content thereof is usually 1 to 45 mol %, preferably 1 to 40 mol %, more preferably 1 to 35 mol %, even more preferably 1 to 20 mol %, and still more preferably 1 to 10 mol %, based on all structural units of resin (A).

[0140] <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 may be a condensed ring of a monocyclic lactone ring and another ring. Preferred examples include a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)). The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), (a3-2), (a3-3) or (a3-4). One of these may be contained alone, or two or more of them may be contained. TIFF0007624807000108.tif50156 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6 are each independently -O- or *-O-(CH2) k3 It represents a group represented by -CO-O- (k3 represents an integer of any of 1 to 7). L a7 , -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OLa9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates the bonding site with the carbonyl group. R a18 , R a19 and R a20 each independently represents a hydrogen atom or a methyl group. R a24 represents an alkyl group having 1 to 6 carbon atoms which may have 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 an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3. w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same or different.]

[0141] R a21 , R a22 , R a23 and R a25 Examples of the aliphatic hydrocarbon group in include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. R a24Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R a24 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group, and preferably includes an alkyl group having 1 to 4 carbon atoms, and more preferably includes a methyl group or an ethyl group. R a24 Examples of the alkyl group having a halogen atom in the formula (I) include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group.

[0142] L a8 and L a9 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group.

[0143] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or *-O-(CH2) k3 In the -CO-O- group, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and further preferably an oxygen atom. R a18 ~R a21 is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group, or a methyl group. p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1.

[0144] In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH2—CO—O— or —O—C2H4—CO—O—. w1 is preferably an integer of 0 to 2, and more preferably 0 or 1. In particular, the formula (a3-4) is preferably the formula (a3-4)'. TIFF0007624807000109.tif4326 (in the formula, R a24 , L a7 has the same meaning as above.)

[0145] Examples of the structural unit (a3) ​​include structural units derived from monomers described in JP 2010-204646 A, JP 2000-122294 A, and JP 2012-41274 A. Examples of the structural unit (a3) ​​include structural units represented by any one of formulas (a3-1-1), (a3-1-2), (a3-2-1), (a3-2-2), (a3-3-1), (a3-3-2), and (a3-4-1) to (a3-4-12), and in the structural unit, R in formulas (a3-1) to (a3-4) a18 , R a19 , R a20 and R a24 A structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom is preferred. TIFF0007624807000110.tif115165 When the resin (A) contains the structural unit (a3), the total content thereof is usually 1 to 70 mol %, preferably 1 to 65 mol %, and more preferably 1 to 60 mol %, based on all structural units in the resin (A). Furthermore, the content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3) or the structural unit (a3-4) is preferably 1 to 60 mol %, more preferably 1 to 50 mol %, and further preferably 1 to 50 mol %, based on all structural units in the resin (A).

[0146] <Structural unit (a4)> Examples of the structural unit (a4) include the following structural units. TIFF0007624807000111.tif3165[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having 1 to 24 carbon atoms and containing a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.] R 42 Examples of the saturated hydrocarbon group represented by the formula (I) include chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups.

[0147] Examples of the chain hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* indicates a bond position): TIFF0007624807000112.tif11160 Examples of groups formed by combinations include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic hydrocarbon group-alkyl group.

[0148] The structural unit (a4) includes at least one structural unit selected from the group consisting of formulae (a4-0), (a4-1), (a4-2), (a4-3) and (a4-4). TIFF0007624807000113.tif3953[In formula (a4-0), R 5a represents a hydrogen atom or a methyl group. L 4a represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 3a represents a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms. R 6a represents a hydrogen atom or a fluorine atom.

[0149] L 4a Examples of the alkanediyl group in the formula (I) include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group.

[0150] L 3aExamples of the perfluoroalkanediyl group in the formula (I) include a difluoromethylene group, a perfluoroethylene group, a perfluoropropane-1,1-diyl group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, a perfluoropentane-1,5-diyl group, a perfluoropentane-2,2-diyl group, a perfluoropentane-3 ,3-diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1,7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3,3-diyl group, and perfluorooctane-4,4-diyl group. L 3a Examples of the perfluorocycloalkanediyl group in the formula (I) include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, and a perfluoroadamantanediyl group.

[0151] L 4a is preferably a single bond, a methylene group, or an ethylene group, and more preferably a single bond or a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0152] The structural unit (a4-0) includes the structural units shown below and R in the structural unit (a4-0) in the structural units shown below. 5a In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF0007624807000114.tif95165

[0153] TIFF0007624807000115.tif5170[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 optionally substituted alkanediyl group having 1 to 6 carbon atoms or a group represented by formula (a-g1), a41 and R a42 At least one of the groups has a halogen atom (preferably a fluorine atom) as a substituent. TIFF0007624807000116.tif1383 [In formula (a-g1), s represents 0 or 1. A a42 and A a44 each independently represents a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. A a43 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. X a41 and X a42 each independently represents -O-, -CO-, -CO-O- or -O-CO-. However, A a42 , A a43 , A a44 , X a41 and X a42 The total number of carbon atoms is 7 or less. * indicates the bond position, and the * on the right is -O-CO-R a42 ]

[0154] R a42 Examples of the saturated hydrocarbon group in include chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these.

[0155] Examples of the chain saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group. Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic saturated hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* indicates a bond position): TIFF0007624807000117.tif11160 Examples of groups formed by combinations include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, such as -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group.

[0156] R a42 The substituent that is has includes at least one selected from the group consisting of a halogen atom and a group represented by formula (a-g3). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable. TIFF0007624807000118.tif752[In 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. * stands for R a42 represents the bond position with However, R a42 -X a43 -A a45 In R a42 When A does not have a halogen atom, a45 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms and having at least one halogen atom.

[0157] A a45 Examples of the aliphatic hydrocarbon group in include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups; monocyclic alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups; and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl, adamantyl, norbornyl, and the following groups (* indicates a bond position). TIFF0007624807000119.tif11160

[0158] R a42 is preferably a saturated hydrocarbon group which may have a halogen atom, and more preferably a saturated hydrocarbon group having an alkyl group having a halogen atom and / or a group represented by formula (a-g3). R a42 When is a saturated hydrocarbon group having a halogen atom, it is preferably a saturated hydrocarbon group having a fluorine atom, more preferably a perfluoroalkyl group or a perfluorocycloalkyl group, further 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 is a saturated hydrocarbon group having a group represented by formula (a-g3), the number of carbon atoms contained in the group represented by formula (a-g3) is a42 The total number of carbon atoms is preferably not more than 15, more preferably not more than 12. In the case where the group represented by formula (a-g3) is contained as a substituent, the number thereof is preferably 1.

[0159] R a42is a saturated hydrocarbon group having a group represented by formula (a-g3), R a42 is more preferably a group represented by formula (a-g2). TIFF0007624807000120.tif874[In formula (a-g2), A a46 represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. X a44 represents **-O-CO- or **-CO-O- (** represents A a46 represents the bond position with. A a47 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. However, A a46 , A a47 and X a44 The total number of carbon atoms in A is 18 or less. a46 and A a47 At least one of these has at least one halogen atom. * indicates the bond position with the carbonyl group.

[0160] A a46 The saturated hydrocarbon group preferably has 1 to 6 carbon atoms, and more preferably has 1 to 3 carbon atoms. A a47 The aliphatic hydrocarbon group preferably has 4 to 15 carbon atoms, more preferably 5 to 12 carbon atoms. a47 is more preferably a cyclohexyl group or an adamantyl group.

[0161] A preferred structure of the group represented by formula (a-g2) is the following structure (* indicates the bonding position with the carbonyl group). TIFF0007624807000121.tif13161

[0162] A a41Examples of the alkanediyl group in the formula (I) include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, and a hexane-1,6-diyl group; and branched alkanediyl groups such as a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a 1-methylbutane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A a41 Examples of the substituent in the alkanediyl group represented by the formula (I) 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 further preferably an ethylene group.

[0163] A in the group represented by formula (a-g1) a42 , A a43 and A a44 Examples of the divalent saturated hydrocarbon group represented by include linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic hydrocarbon groups, and groups formed by combining alkanediyl groups and divalent alicyclic hydrocarbon groups, 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.

[0164] In the group represented by formula (a-g1), X a42 Examples of the group in which is -O-, -CO-, -CO-O-, or -O-CO- include the following groups. In the following examples, * and ** each represent a bond position, and ** represents -O-CO-Ra42 This is the bonding position with. TIFF0007624807000122.tif48153

[0165] 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. TIFF0007624807000123.tif100142

[0166] TIFF0007624807000124.tif122141

[0167] The structural unit represented by formula (a4-1) is preferably a structural unit represented by formula (a4-2). TIFF0007624807000125.tif3454[In formula (a4-2), R f5 represents a hydrogen atom or a methyl group. L 44 represents an alkanediyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-. R f6 represents a saturated hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom. However, L 44 and R f6 The total number of carbon atoms in the molecule is limited to 21.

[0168] L 44 The alkanediyl group of A a41 Examples of the groups include the same groups as those exemplified in the above. R f6 The saturated hydrocarbon group of R a42 Examples of the groups include the same groups as those exemplified in the above. L 44 The alkanediyl group in is preferably an alkanediyl group having 2 to 4 carbon atoms, and more preferably an ethylene group.

[0169] Examples of the structural unit represented by formula (a4-2) include structural units represented by formulas (a4-1-1) to (a4-1-11). f5 The structural unit represented by formula (a4-2) also includes a structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom.

[0170] TIFF0007624807000126.tif5164[In formula (a4-3), R f7 represents a hydrogen atom or a methyl group. L 5 represents an alkanediyl group having 1 to 6 carbon atoms. A f13 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms which may contain a fluorine atom. X f12 is *-O-CO- or *-CO-O-(* is A f13 represents the bonding position with. A f14 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may contain a fluorine atom. However, A f13 and A f14 At least one of L has a fluorine atom. 5 , A f13 and A f14 The total number of carbon atoms in the molecule is limited to 20.

[0171] L 5 The alkanediyl group in a41 Examples of the alkanediyl group include the same groups as those exemplified as the alkanediyl group. A f13 The divalent saturated hydrocarbon group which may have a fluorine atom in is preferably a divalent chain saturated hydrocarbon group which may have a fluorine atom and a divalent alicyclic saturated hydrocarbon group which may have a fluorine atom, and more preferably a perfluoroalkanediyl group. Examples of the divalent chain hydrocarbon group which may have a fluorine atom include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group; and perfluoroalkanediyl groups such as a difluoromethylene group, a perfluoroethylene group, a perfluoropropanediyl group, a perfluorobutanediyl group, and a perfluoropentanediyl group. The divalent alicyclic 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.

[0172] A f14 The saturated hydrocarbon group and the saturated hydrocarbon group which may have a fluorine atom are represented by R a42 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, Preferred are fluorinated alkyl groups such as a hexyl group, a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group, and a perfluorooctyl group, a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, an adamantyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, and a perfluoroadamantylmethyl group.

[0173] In formula (a4-3), L 5 is preferably an ethylene group. A f13The divalent saturated hydrocarbon group 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. 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, or an adamantyl group.

[0174] Examples of the structural unit represented by formula (a4-3) include structural units represented by formulas (a4-1'-1) to (a4-1'-11). R in the structural unit (a4-3) f7 The structural unit represented by formula (a4-3) also includes a structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom.

[0175] The structural unit (a4) also includes a structural unit represented by the formula (a4-4). TIFF0007624807000127.tif4365[In formula (a4-4), R f21 represents a hydrogen atom or a methyl group. A f21 is -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -or-(CH2) j4 -CO-O-(CH2) j5 - represents. j1 to j5 each independently represent an integer of 1 to 6. R f22 represents a saturated hydrocarbon group having 1 to 10 carbon atoms and containing a fluorine atom.]

[0176] R f22 The saturated hydrocarbon group of R a42The saturated hydrocarbon group represented by 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 further preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom. In formula (a4-4), A f21 As an example, -(CH2) j1 - is preferred, an ethylene group or a methylene group is more preferred, and a methylene group is even more preferred.

[0177] Examples of the structural unit represented by formula (a4-4) include the following structural units and structural units represented by the following formulas: f21 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF0007624807000128.tif87160 When the resin (A) has the structural unit (a4), the content thereof is preferably from 1 to 20 mol %, more preferably from 2 to 15 mol %, and even more preferably from 3 to 10 mol %, based on all structural units in the resin (A).

[0178] <Structural unit (a5)> The non-leaving hydrocarbon group contained in the structural unit (a5) may be a group containing a linear, branched or cyclic hydrocarbon group. Among these, the structural unit (a5) is preferably a group containing an alicyclic hydrocarbon group. An example of the structural unit (a5) is a structural unit represented by the formula (a5-1). TIFF0007624807000129.tif3972[In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.]

[0179] 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, a norbornyl group, and the like. 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. An example of the alicyclic hydrocarbon group having a substituent is a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group.

[0180] L 55 Examples of the divalent saturated hydrocarbon group in include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and a divalent chain saturated hydrocarbon group is preferred. Examples of the divalent chain saturated hydrocarbon group include alkanediyl 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 cycloalkanediyl groups such as cyclopentanediyl and cyclohexanediyl. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl and norbornanediyl.

[0181] L 55Examples of the divalent saturated hydrocarbon group represented by formula (L1-1) to formula (L1-4) in which -CH2- is replaced with -O- or -CO- include groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** represent bonding positions, and * represents bonding position with an oxygen atom. TIFF0007624807000130.tif18165 formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 represents the bond position with. L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, L x1 and L x2 The total number of carbon atoms is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, L x3 and L x4 The total number of carbon atoms is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, L x5 , L x6 and L x7 The total number of carbon atoms is 15 or less. In formula (L1-4), L x8 and L x9 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, L x8 , L x9 and W x1 The total number of carbon atoms is 15 or less.

[0182] 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, and more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and 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, and 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, and 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, and more preferably a cyclohexanediyl group or an adamantanediyl group.

[0183] Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF0007624807000131.tif54134

[0184] Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF0007624807000132.tif24131

[0185] Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF0007624807000133.tif15145

[0186] Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF0007624807000134.tif26114L 55 is preferably a single bond or a group represented by formula (L1-1).

[0187] The structural unit (a5-1) may be any of the structural units shown below and R in the structural unit (a5-1) in the structural unit shown below. 51 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. When the resin (A) has the structural unit (a5), the content thereof is preferably from 1 to 30 mol %, more preferably from 2 to 20 mol %, and even more preferably from 3 to 15 mol %, based on all structural units in the resin (A).

[0188] <Structural unit (II)> The resin (A) may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter, may be referred to as "structural unit (II)"). Specific examples of the structural unit (II) include structural units described in JP-A-2016-79235, and are preferably structural units having a sulfonate group or carboxylate group and an organic cation in a side chain, or a structural unit having a sulfonio group and an organic anion in a side chain.

[0189] The structural unit having a sulfonate group or carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (II-2-A'). TIFF0007624807000136.tif36104[In formula (II-2-A'), X III3 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, in which -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. Z.A. + represents an organic cation.

[0190] R III3 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R III3 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom and is represented by the formula: a8 Examples of the alkyl group include the same alkyl groups having 1 to 6 carbon atoms which may have a halogen atom and are represented by the following formula: A x1Examples of the alkanediyl group having 1 to 8 carbon atoms represented by the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A x1 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms which may be substituted include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. X III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by the formula (I) include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and a combination thereof. Specifically, straight-chain alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, and dodecane-1,12-diyl group; butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, Examples of the divalent alkyl group include branched alkanediyl groups such as pan-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group; cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; and divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. Examples of saturated hydrocarbon groups in which -CH2- is replaced with -O-, -S-, or -CO- include divalent groups represented by formulae (X1) to (X53). However, the number of carbon atoms before the -CH2- in the saturated hydrocarbon group is replaced with -O-, -S-, or -CO- is 17 or less. In the following formulae, * and ** represent the bond position, * represents A x1 represents the bonding position with TIFF0007624807000137.tif145161

[0191] 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.

[0192] ZA in formula (II-2-A') + represents the cation Z1 in the acid generator (B1). + The same can be mentioned.

[0193] The structural unit represented by formula (II-2-A') is preferably a structural unit represented by formula (II-2-A). TIFF0007624807000138.tif38109 [In formula (II-2-A), R III3 , X III3 and Z.A. + has the same meaning as above. z2A represents an integer of 0 to 6. R III2 and R III4each independently represents a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 6 carbon atoms; when z2A is 2 or more, III2 and R III4 may be the same as or different from each other. Q a and Q b each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.] R III2 , R III4 , Q a and Q b As the perfluoroalkyl group having 1 to 6 carbon atoms represented by the formula b1 Examples of the perfluoroalkyl group include those having 1 to 6 carbon atoms represented by the following formula:

[0194] The structural unit represented by formula (II-2-A) is preferably a structural unit represented by formula (II-2-A-1). TIFF0007624807000139.tif5578 [In formula (II-2-A-1), R III2 , R III3 , R III4 , Q a , Q b and Z.A. + has the same meaning as above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. z2A1 represents an integer of 0 to 6. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, -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 hydroxyl group.] R III5Examples of the saturated hydrocarbon group having 1 to 12 carbon atoms represented by the formula (I) include linear or branched alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. X I2 As the divalent saturated hydrocarbon group represented by the formula: III3 Examples of the divalent saturated hydrocarbon group include those similar to those represented by the following formula:

[0195] The structural unit represented by formula (II-2-A-1) is more preferably a structural unit represented by formula (II-2-A-2). TIFF0007624807000140.tif5288 [In formula (II-2-A-2), R III3 , R III5 and Z.A. + has the same meaning as above. mA and nA each independently represent 1 or 2.

[0196] Examples of the structural unit represented by formula (II-2-A') include the following structural units, R III3 Examples of the structural units include those in which the group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom) or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.), and the structural units described in WO 2012 / 050015. + represents an organic cation. TIFF0007624807000141.tif86163

[0197] 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). TIFF0007624807000142.tif3791 [In formula (II-1-1), A II1 represents a single bond or a divalent linking group. R II1represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R II2 and R II3 each independently represents a hydrocarbon group having 1 to 18 carbon atoms; R II2 and R II3 may be bonded to each other to form a ring together with the sulfur atom to which they are attached. R II4 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A - represents an organic anion. R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by the formula (I) include a phenylene group and a naphthylene group. R II2 and R II3 Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. R II4 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R II4 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom and is represented by the formula: a8 Examples of the alkyl group include the same alkyl groups having 1 to 6 carbon atoms which may have a halogen atom and are represented by the following formula: A II1 Examples of the divalent linking group represented by the formula (I) include a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-. III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms include those represented by the following formula:

[0198] The structural unit containing a cation in formula (II-1-1) includes the structural units represented by the following formula and R II4 and structural units in which a group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a fluorine atom, a trifluoromethyl group, or the like. TIFF0007624807000143.tif84130

[0199] A - Examples of the organic anion represented by the formula (I) include a sulfonate anion, a sulfonylimide anion, a sulfonylmethide anion, and a carboxylate anion. - The organic anion represented by the formula (B1) is preferably a sulfonate anion, and the sulfonate anion is more preferably an anion contained in the salt represented by the formula (B1) above.

[0200] A - Examples of the sulfonylimide anion represented by the formula (I) include the following. TIFF0007624807000144.tif43135

[0201] Examples of sulfonylmethide anions include the following: TIFF0007624807000145.tif29123

[0202] Examples of carboxylate anions include the following: TIFF0007624807000146.tif51153

[0203] Examples of the structural unit represented by formula (II-1-1) include structural units represented below. TIFF0007624807000147.tif161141 When the structural unit (II) is contained in the resin (A), the content of the structural unit (II) is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and even more preferably 3 to 10 mol %, based on the total structural units of the resin (A).

[0204] The resin (A) may have structural units other than the above-mentioned structural units, and examples of such structural units include structural units well known in the art.

[0205] The resin (A) is preferably a resin composed of the structural unit (a1) and the structural unit (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1) and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group and a cyclopentyl group), more preferably at least two, and even more preferably the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by formula (a2-A) or a structural unit represented by formula (a2-1). The structural unit (a3) ​​is preferably at least one selected from the group consisting of the structural unit represented by formula (a3-1), the structural unit represented by formula (a3-2), and the structural unit represented by formula (a3-4).

[0206] 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 (e.g., radical polymerization method) using a monomer that leads to these structural units. The content of each structural unit contained in the resin (A) can be adjusted by the amount of the monomer used for polymerization. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, and even more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, and even more preferably 15,000 or less). In the present specification, the weight average molecular weight is a value determined by gel permeation chromatography under the conditions described in the Examples.

[0207] <Resins other than resin (A)> The resist composition of the present invention may contain a resin other than the resin (A) in combination. Examples of resins other than resin (A) include resins containing the structural unit (a4) or the structural unit (a5) (hereinafter, sometimes referred to as resin (X)). As the resin (X), a resin containing the structural unit (a4) is particularly preferable. In the resin (X), the content of the structural unit (a4) is preferably 30 mol % or more, more preferably 40 mol % or more, and even more preferably 45 mol % or more, based on the total of all structural units in the resin (X). Examples of structural units that may be further contained in the resin (X) include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. Among these, the resin (X) is preferably a resin consisting only of the structural unit (a4) and / or the structural unit (a5), and more preferably a resin consisting only of the structural unit (a4). Each structural unit constituting the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization method) using a monomer that derives these structural units. The content of each structural unit in the resin (X) can be adjusted by the amount of the monomer 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 method for measuring the weight average molecular weight of the resin (X) is the same as that for the resin (A). Furthermore, when the resist composition contains resin (X), the content thereof is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, even more preferably 1 to 40 parts by mass, particularly preferably 1 to 30 parts by mass, and particularly preferably 1 to 8 parts by mass, relative to 100 parts by mass of resin (A).

[0208] The content of resin (A) in the resist composition is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. When a resin other than resin (A) is contained, the total content of resin (A) and the resin other than resin (A) is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. The solid content of the resist composition and the resin content therein can be measured by a known analytical means such as liquid chromatography or gas chromatography.

[0209] <Solvent (E)> The content of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less, 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 of the solvent (E) can be measured by a known analytical method such as liquid chromatography or gas chromatography. Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; etc. One type of solvent (E) may be used alone, or two or more types may be used.

[0210] <Quencher (C)> The quencher (C) may be a basic nitrogen-containing organic compound or a salt (excluding the carboxylate represented by formula (I)) that generates an acid with a weaker acidity than the acid generated from the acid generator (B). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15 mass %, and more preferably about 0.1 to 10 mass %, based on the solid content of the resist composition. The basic nitrogen-containing organic compound includes amines and ammonium salts. The amines include aliphatic amines and aromatic amines. The aliphatic amines include primary amines, secondary amines, and tertiary amines. Amines include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, Amines, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine amine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane Examples of the amines include 1,2-di(4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, and bipyridine. Preferred are aromatic amines such as diisopropylaniline, and more preferred are 2,6-diisopropylaniline. Examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, choline, and the like.

[0211] 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. The salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is preferably a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (B) (a salt having a carboxylic acid anion), and more preferably the weak acid inner salt (D). TIFF0007624807000148.tif113145

[0212] Examples of the weak acid inner salt (D) include the following salts. TIFF0007624807000149.tif95145

[0213] 〈Other components〉 The resist composition of the present invention may contain components other than the above-mentioned components (hereinafter, sometimes referred to as "other components (F)") as necessary. 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.

[0214] Preparation of Resist Composition The resist composition of the present invention can be prepared by mixing the carboxylate (I), the resin (A), the acid generator (B), and, if necessary, the resin other than the resin (A), the solvent (E), the quencher (C), and other components (F). The order of mixing is arbitrary and is not particularly limited. The temperature during mixing can be selected from 10 to 40°C depending on the type of resin, the solubility of the resin in the solvent (E), and the like. The mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is not particularly limited, and stirring and mixing can be used. After mixing the components, it is preferable to filter the mixture using a filter having a pore size of about 0.003 to 0.2 μm.

[0215] <Method for Producing Resist Pattern> The method for producing a resist pattern of the present invention comprises the steps of: (1) applying the resist composition of the present invention onto a substrate; (2) A step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) A step of developing the composition layer after heating. The resist composition can be applied onto a substrate using a commonly used device such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers. Before applying the resist composition, the substrate may be cleaned, and an anti-reflective film or the like may be formed on the substrate. The composition after coating is dried to remove the solvent and form a composition layer. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or by using a vacuum device. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 10 to 180 seconds. The pressure during drying under reduced pressure is preferably 1 to 1.0×10 5 It is preferable that the pressure is about Pa. The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, various types can be used, such as those that emit ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), and F2 excimer laser (wavelength 157 nm), those that convert the wavelength of laser light from a solid laser light source (YAG or semiconductor laser, etc.) to emit harmonic laser light in the far ultraviolet or vacuum ultraviolet range, and those that irradiate electron beams or extreme ultraviolet light (EUV). In this specification, irradiation with these types of radiation may be collectively referred to as "exposure". During exposure, exposure is usually performed through a mask corresponding to the desired pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask. The composition layer after exposure is subjected to a heat treatment (so-called post-exposure bake) in order to promote the deprotection reaction of the acid labile groups. The heating temperature is usually about 50 to 200°C, preferably about 70 to 150°C. The composition layer after heating is usually developed using a developing device and a developer. Examples of the developing method include a dip method, a paddle method, a spray method, and a dynamic dispense method. The developing temperature is preferably, for example, 5 to 60° C., and the developing time is preferably, for example, 5 to 300 seconds. By selecting the type of developer as follows, a positive resist pattern or a negative resist pattern can be produced. When a positive resist pattern is produced from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. For example, an aqueous solution of tetramethylammonium hydroxide or (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline) may be used. The alkaline developer may contain a surfactant. After development, the resist pattern is preferably washed with ultrapure water, and then water remaining on the substrate and the pattern is removed. 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 organic solvents contained in organic developers include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; and aromatic hydrocarbon solvents such as anisole. The content of the organic solvent in the organic developer is preferably from 90% by mass to 100% by mass, more preferably from 95% by mass to 100% by mass, and further preferably consists essentially of the organic solvent. Among them, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. The total content of butyl acetate and 2-heptanone in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant and may contain a small amount of water. During development, the development may be stopped by replacing the organic developer with a different type of solvent. The resist pattern after development is preferably washed with a rinse solution. There are no particular limitations on the rinse solution as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After cleaning, it is preferable to remove any rinsing liquid remaining on the substrate and the pattern.

[0216] <Application> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, in particular as a resist composition for electron beam (EB) exposure or a resist composition for EUV exposure, and is useful for semiconductor microfabrication. EXAMPLES

[0217] The present invention will be described in more detail with reference to examples. In the examples, "%" and "parts" expressing the content or amount used are based on mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography under the following analytical conditions: Column: TSKgel Multipore HXL-M x 3 + guard column (Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0mL / min Detector: RI detector Column temperature: 40℃ Injection volume: 100μl Molecular weight standard: Standard polystyrene (Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC: Agilent 1100 model, MASS: Agilent LC / MSD model). In the following examples, the value of this molecular ion peak is indicated by "MASS".

[0218] Example 1: Synthesis of a salt represented by formula (I-164) TIFF0007624807000150.tif33148 4.76 parts of the compound represented by formula (I-164-a) and 6.40 parts of Oxone (registered trademark) were mixed, stirred at 23 ° C. for 30 minutes, and then cooled to 5 ° C. 23.56 parts of sulfuric acid were added to the resulting mixture, and then stirred at 5 ° C. for 30 minutes. A mixed solution of 4.15 parts of the compound represented by formula (I-164-b) and 20.74 parts of chloroform was added to the resulting mixture, stirred at 5 ° C. for 30 minutes, and then further stirred at 23 ° C. for 2 hours. The resulting mixed solution was added to 120 parts of methanol, stirred at 23 ° C. for 30 minutes, and then filtered. The resulting filtrate was concentrated, and then 125 parts of chloroform and 25 parts of acetonitrile were added to the concentrated residue, stirred at 23 ° C. for 30 minutes, and then 50 parts of 5% hydrochloric acid was added and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 40 parts of ion-exchanged water was added to the obtained organic layer, and the mixture was stirred at 23°C for 30 minutes, and then separated to separate the organic layer. This water washing operation was repeated three times. The obtained organic layer was concentrated, and 45 parts of tert-butyl methyl ether was added to the concentrated mixture, and the mixture was stirred at 23°C for 30 minutes, and then filtered to obtain 3.33 parts of the salt represented by formula (I-164-c). TIFF0007624807000151.tif51148 0.69 parts of the salt represented by formula (I-164-d), 1.12 parts of the salt represented by formula (I-164-c) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of 5% oxalic acid aqueous solution were added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water were added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.02 parts of the salt represented by formula (I-164). MASS(ESI(+)Spectrum):M + 395.1 MASS(ESI(-)Spectrum):M - 193.1

[0219] Example 2: Synthesis of a salt represented by formula (I-326) TIFF0007624807000152.tif26143 9 parts of potassium iodate, 14.39 parts of a compound represented by formula (I-326-a), 27 parts of acetic acid, and 13.5 parts of acetic anhydride were mixed and stirred at 23 ° C. for 30 minutes, and then cooled to 5 ° C. To the resulting mixture, 9 parts of sulfuric acid were added over 10 minutes, and the mixture was stirred at 5 ° C. for 3 hours, and then further stirred at 23 ° C. for 12 hours. To the resulting mixture, 27 parts of tert-butyl methyl ether and 27 parts of ion-exchanged water were added, and the mixture was stirred at 23 ° C. for 2 hours, and then filtered, and the obtained filtrate was separated to take out the organic layer. To the resulting organic layer, a mixed solution of 4.5 parts of sodium bromide and 13.5 parts of ion-exchanged water was added, and the mixture was stirred at 23 ° C. for 2 hours, and then filtered to obtain 2.59 parts of a salt represented by formula (I-326-b). TIFF0007624807000153.tif55148 0.69 parts of the salt represented by formula (I-164-d), 1.24 parts of the salt represented by formula (I-326-b) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of 5% oxalic acid aqueous solution was added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water was added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.56 parts of the salt represented by formula (I-326). MASS(ESI(+)Spectrum):M + 397.0 MASS(ESI(-)Spectrum):M - 193.1

[0220] Example 3: Synthesis of a salt represented by formula (I-596) TIFF0007624807000154.tif26161 9 parts of potassium iodate, 27 parts of a compound represented by formula (I-596-a), 27 parts of acetic acid, and 13.5 parts of acetic anhydride were mixed and stirred at 23 ° C. for 30 minutes, and then cooled to 5 ° C. To the resulting mixture, 9 parts of sulfuric acid were added over 10 minutes, and the mixture was stirred at 5 ° C. for 3 hours, and then further stirred at 23 ° C. for 12 hours. To the resulting mixture, 27 parts of tert-butyl methyl ether and 27 parts of ion-exchanged water were added, and the mixture was stirred at 23 ° C. for 2 hours, and then filtered, and the obtained filtrate was separated to take out the organic layer. To the resulting organic layer, a mixed solution of 4.5 parts of sodium bromide and 13.5 parts of ion-exchanged water was added, and the mixture was stirred at 23 ° C. for 2 hours, and then filtered to obtain 4.68 parts of a salt represented by formula (I-596-b). TIFF0007624807000155.tif57145 0.69 parts of the salt represented by formula (I-164-d), 1.86 parts of the salt represented by formula (I-596-b) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of a 5% aqueous oxalic acid solution were added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water were added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.39 parts of the salt represented by formula (I-596). MASS(ESI(+)Spectrum):M + 637.2 MASS(ESI(-)Spectrum):M - 193.1

[0221] Example 4: Synthesis of a salt represented by formula (I-166) TIFF0007624807000156.tif59154 1.03 parts of the salt represented by formula (I-166-d), 1.12 parts of the salt represented by formula (I-164-c) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of 5% oxalic acid aqueous solution was added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water was added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.33 parts of the salt represented by formula (I-166). MASS(ESI(+)Spectrum):M + 395.1 MASS(ESI(-)Spectrum):M - 337.1

[0222] Example 5: Synthesis of a salt represented by formula (I-328) TIFF0007624807000157.tif67148 1.03 parts of the salt represented by formula (I-166-d), 1.24 parts of the salt represented by formula (I-326-b) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of 5% oxalic acid aqueous solution was added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water was added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.39 parts of the salt represented by formula (I-328). MASS(ESI(+)Spectrum):M + 397.0 MASS(ESI(-)Spectrum):M - 337.1

[0223] Example 6: Synthesis of salt represented by formula (I-220) TIFF0007624807000158.tif36146 5.01 parts of the compound represented by formula (I-220-a) and 6.40 parts of Oxone (registered trademark) were mixed, stirred at 23 ° C for 30 minutes, and then cooled to 5 ° C. 23.56 parts of sulfuric acid were added to the resulting mixture, and then stirred at 5 ° C for 30 minutes. A mixed solution of 4.15 parts of the compound represented by formula (I-164-b) and 20.74 parts of chloroform was added to the resulting mixture, stirred at 5 ° C for 30 minutes, and then further stirred at 23 ° C for 2 hours. The resulting mixed solution was added to 120 parts of methanol, stirred at 23 ° C for 30 minutes, and then filtered. The recovered filtrate was concentrated, and then 125 parts of chloroform and 25 parts of acetonitrile were added to the concentrated residue, stirred at 23 ° C for 30 minutes, added 50 parts of 5% hydrochloric acid, and stirred at 23 ° C for 30 minutes, and then separated to take out the organic layer. 40 parts of ion-exchanged water was added to the obtained organic layer, and the mixture was stirred at 23° C. for 30 minutes, and then separated to separate the organic layer. This water washing operation was repeated three times. The obtained organic layer was concentrated, and 45 parts of tert-butyl methyl ether was added to the concentrated mixture, and the mixture was stirred at 23° C. for 30 minutes, and then filtered to obtain 3.48 parts of the salt represented by formula (I-220-c). TIFF0007624807000159.tif59154 1.03 parts of the salt represented by formula (I-166-d), 1.16 parts of the salt represented by formula (I-220-c) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of 5% oxalic acid aqueous solution was added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water was added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.46 parts of the salt represented by formula (I-220). MASS(ESI(+)Spectrum):M + 409.1 MASS(ESI(-)Spectrum):M - 337.1

[0224] Example 7: Synthesis of a salt represented by formula (I-274) TIFF0007624807000160.tif41152 5.26 parts of the compound represented by formula (I-274-a) and 6.40 parts of Oxone (registered trademark) were mixed, stirred at 23 ° C for 30 minutes, and then cooled to 5 ° C. 23.56 parts of sulfuric acid were added to the resulting mixture, and then stirred at 5 ° C for 30 minutes. A mixed solution of 4.15 parts of the compound represented by formula (I-164-b) and 20.74 parts of chloroform was added to the resulting mixture, stirred at 5 ° C for 30 minutes, and then further stirred at 23 ° C for 2 hours. The resulting mixed solution was added to 120 parts of methanol, stirred at 23 ° C for 30 minutes, and then filtered. The recovered filtrate was concentrated, and then 125 parts of chloroform and 25 parts of acetonitrile were added to the concentrated residue, stirred at 23 ° C for 30 minutes, added 50 parts of 5% hydrochloric acid, and stirred at 23 ° C for 30 minutes, and then separated to take out the organic layer. 40 parts of ion-exchanged water was added to the obtained organic layer, and the mixture was stirred at 23° C. for 30 minutes, and then separated to separate the organic layer. This water washing operation was repeated three times. The obtained organic layer was concentrated, and 45 parts of tert-butyl methyl ether was added to the concentrated mixture, and the mixture was stirred at 23° C. for 30 minutes, and then filtered to obtain 3.13 parts of the salt represented by formula (I-274-c). TIFF0007624807000161.tif59154 1.03 parts of the salt represented by formula (I-166-d), 1.19 parts of the salt represented by formula (I-274-c) and 10 parts of chloroform were mixed and stirred at 23 ° C. for 12 hours. 5 parts of 5% oxalic acid aqueous solution was added to the obtained mixture and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. 5 parts of ion-exchanged water was added to the obtained organic layer and stirred at 23 ° C. for 30 minutes, and then the organic layer was separated and taken out. This water washing operation was repeated five times. The obtained organic layer was concentrated to obtain 1.41 parts of the salt represented by formula (I-274). MASS(ESI(+)Spectrum):M + 423.1 MASS(ESI(-)Spectrum):M - 337.1

[0225] Resin synthesis The compounds (monomers) used in the synthesis of resin (A) are shown below. Hereinafter, these compounds will be referred to as "monomer (a1-1-3)" etc. according to their formula numbers. TIFF0007624807000162.tif44145

[0226] Synthesis Example 1: Synthesis of Resin A1 Monomers (a1-1-3), (a1-2-6), (a2-1-1) and (a3-4-2) were used as monomers, and the molar ratio [monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-1):monomer (a3-4-2)] was mixed to 45:14:2.5:38.5, and propylene glycol monomethyl ether acetate was added in an amount of 1.5 times the total monomer amount to form a solution. Azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) were added as initiators to this solution in amounts of 1 mol% and 3 mol%, respectively, relative to the total monomer amount, and these were heated at 73°C for about 5 hours. The resulting reaction mixture was poured into a large amount of a methanol / water mixed solvent to precipitate a resin, and the resin was filtered. The obtained resin was dissolved again in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin. This reprecipitation procedure was repeated twice to filter the resin, resulting in a weight-average molecular weight of 7.8 × 10 3 Resin A1 was obtained in a yield of 69%. This resin A1 has the following structural units. TIFF0007624807000163.tif36125

[0227] Synthesis Example 2: Synthesis of Resin X1 Monomer (a5-1-1) and monomer (a4-0-12) were used as monomers, and mixed in a molar ratio of 50:50 [monomer (a5-1-1):monomer (a4-0-12)], and 1.2 times the mass of the total monomer amount of methyl isobutyl ketone was added to make a solution. Azobis(2,4-dimethylvaleronitrile) was added as an initiator to this solution in an amount of 3 mol% relative to the total monomer amount, and the solution was heated at 70°C for about 5 hours. The resulting reaction mixture was poured into a large amount of a methanol / water mixed solvent to precipitate a resin, which was then filtered and the weight average molecular weight of the resin was 1.0×10 4 Resin X1 was obtained in a yield of 91%. This resin X1 has the following structural units. TIFF0007624807000164.tif3082

[0228] <Preparation of resist composition> As shown in Table 2, the following components were mixed and the resulting mixture was filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

[0229] [Table 2]

[0230] <Resin> A1, X1: Resin A1, Resin X1 <Acid Generator (B)> B1-21: A salt represented by the formula (B1-21) B1-22: a salt represented by the formula (B1-22) TIFF0007624807000166.tif3196<Carboxylate(I)> I-164: A salt represented by the formula (I-164) I-166: A salt represented by the formula (I-166) I-220: A salt represented by the formula (I-220) I-274: A salt represented by the formula (I-274) I-326: A salt represented by the formula (I-326) I-328: A salt represented by the formula (I-328) I-596: A salt represented by the formula (I-596) <Carboxylic Acid Generator (IX)> IX-1: TIFF0007624807000167.tif3151IX-2: TIFF0007624807000168.tif3153IX-3: TIFF0007624807000169.tif1750IX-4: TIFF0007624807000170.tif3572<solvent> Propylene glycol monomethyl ether acetate 265 parts Propylene glycol monomethyl ether 20 parts 2-Heptanone 20 parts γ-butyrolactone 3.5 parts

[0231] <Production and Evaluation of Resist Patterns> A composition for organic anti-reflective coating (ARC-29; manufactured by Nissan Chemical Industries, Ltd.) was applied to a silicon wafer and baked at 205° C. for 60 seconds to form an organic anti-reflective coating with a thickness of 78 nm on the wafer. Next, the resist composition was applied (spin-coated) onto the organic anti-reflective coating so that the film thickness after drying would be 85 nm. After application, the silicon wafer was pre-baked on a direct hot plate at the temperature shown in the “PB” column of Table 2 for 60 seconds to form a composition layer. The silicon wafer on which the composition layer was formed was exposed to light using an ArF excimer stepper for immersion exposure (XT:1900Gi; manufactured by ASML, NA=1.35, 3 / 4 Annular XY polarization) with a mask for forming a contact hole pattern (hole pitch 90 nm / hole diameter 55 nm) while changing the exposure dose stepwise. Note that ultrapure water was used as the immersion medium. After exposure, post-exposure baking was performed on a hot plate for 60 seconds at the temperature shown in the "PEB" column in Table 2. Next, the composition layer on this silicon wafer was developed by a dynamic dispensing method at 23°C for 20 seconds using butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a developer to produce a negative resist pattern.

[0232] In the resist pattern obtained after development, the exposure amount at which the diameter of a hole formed using the mask was 45 nm was defined as effective sensitivity.

[0233] <Mask Error Factor (MEF) evaluation> For the effective sensitivity, resist patterns were formed using masks with mask hole diameters (hole diameters of the light-transmitting parts of the mask) of 57 nm, 56 nm, 55 nm, 54 nm, and 53 nm (hole pitch of all 90 nm). The slope of the regression line when the mask hole diameter is plotted on the horizontal axis and the hole diameter of the resist pattern formed (transferred) on the substrate by exposure on the vertical axis was calculated as the MEF value. The results are shown in Table 3. The values ​​in the table indicate MEF values.

[0234] [Table 3] Compared with the comparative compositions 1 to 4, the compositions 1 to 7 had a smaller slope of the regression line and exhibited good mask error factor (MEF) evaluation. [Industrial Applicability]

[0235] INDUSTRIAL APPLICABILITY The carboxylate of the present invention and the resist composition containing the carboxylate are capable of obtaining a resist pattern having an excellent mask error factor (MEF), and therefore are suitable for semiconductor microfabrication and extremely useful industrially.

Claims

1. A carboxylate represented by formula (I): [In formula (I), R １ａ and R ２ａ each independently represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a fluorine atom, an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a fluorine atom, or a group combining an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a fluorine atom and an alkyl group having 1 to 12 carbon atoms, or R １ａ and R ２ａ and bond to each other to form an alicyclic hydrocarbon ring having 3 to 16 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms. R ３ａ represents a hydrogen atom, or R １ａ and R ２ａ and R ３ａ and bond to each other to form an alicyclic hydrocarbon ring having 3 to 16 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms. -O-CO-CR １ａ R ２ａ R ３ａ is -O-CO-CR １ｄ R ２ｄ R ３ｄ (R １ｄ and R ２ｄ R each independently represents a hydrogen atom or a fluorine atom-containing alkyl group having 1 to 6 carbon atoms. ３ｄ represents an alkyl group having 1 to 6 carbon atoms and containing a fluorine atom. —O—CO—CR 1a R 2a R 3a is bonded to the benzene ring at the para position relative to I + . R ４ represents a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 12 carbon atoms. R ５ is a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or -O-CO-CR １ｂ R ２ｂ R ３ｂ Represents. R ５ is I in the benzene ring ＋ and at least one R 5 is bonded to the benzene ring at a para position relative to I + . R １ｂ and R ２ｂ each independently represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a fluorine atom, an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a fluorine atom, or a group combining an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a fluorine atom and an alkyl group having 1 to 12 carbon atoms, or R １ｂ and R ２ｂ and bond to each other to form an alicyclic hydrocarbon ring having 3 to 16 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms. R ３ｂ represents a hydrogen atom, or R １ｂ and R ２ｂ and R ３ｂ and bond to each other to form an alicyclic hydrocarbon ring having 3 to 16 carbon atoms which may have a fluorine atom or an alkyl group having 1 to 6 carbon atoms. m4 represents 0 or 1. m5 represents an integer of 0 to 2, and when m5 is 2 or more, a plurality of R ５ may be the same or different from each other. X ０ represents an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent (-CH contained in the alicyclic hydrocarbon group). 2 - may be replaced by -O- or -CO-), a group combining an alicyclic hydrocarbon group having 3 to 24 carbon atoms with a chain hydrocarbon group having 1 to 18 carbon atoms (the -CH ２ - may be replaced by -O- or -CO-, and the alicyclic hydrocarbon group and the chain hydrocarbon group may have a substituent.), or represents an aromatic hydrocarbon group having 6 to 24 carbon atoms which may have a substituent.]

2. X ０ is an alicyclic hydrocarbon group which may have a fluorine atom or a hydroxyl group (-CH contained in the alicyclic hydrocarbon group) 2 - may be replaced by -O- or -CO-) or a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are combined (the -CH 2 The carboxylate according to claim 1, wherein - may be replaced by -O- or -CO-, and the alicyclic hydrocarbon group and the chain hydrocarbon group may have a fluorine atom or a hydroxyl group.

3. A carboxylic acid generator comprising the carboxylate according to claim 1 or 2.

4. 4. A resist composition comprising the carboxylic acid generator according to claim 3, an acid generator other than said carboxylic acid generator, and a resin having an acid labile group.

5. 5. The resist composition according to claim 4, wherein the resin having an acid labile group is a resin containing at least one member 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 are each independently -O- or *-O-(CH ２ ) ｋ１ represents --CO--O--, k1 represents an integer of 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 ａ７ each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a combination thereof. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

6. 6. The resist composition according to claim 4, further comprising a resin that includes a structural unit having a fluorine atom.

7. (1) A step of applying the resist composition according to any one of claims 4 to 6 onto a substrate; (2) A step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising the steps of:

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