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

Abstract

To provide a salt, an acid generator, and a resist composition capable of producing a resist pattern having a good line edge roughness (LER).SOLUTION: A salt, an acid generator, and a resist composition are represented by a formula (I), [in the formula, L1 indicates a group of a formula (L1-1X); X0X, X1X, and X2X each indicate a bivalent aliphatic hydrocarbon group; -CH2- contained in the aliphatic hydrocarbon group may be substituted by -O-, -CO- or -NR3-, whereas at least one of the -CH2- contained in the aliphatic hydrocarbon group is substituted by -O-, -CO- or -NR3- in each of the X0X, X1X, and X2X; RL indicates a hydrogen atom or an aliphatic hydrocarbon group; R3 indicates a hydrogen atom or an alkyl group; R1 and R2 indicate a hydrocarbon group that may each have a substituent; n indicates an integer of 1-3; and Z+ indicates an organic cation].SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002] Patent Document 1 describes a resist composition containing, as an acid generator, a salt represented by the following formula. TIFF0007704517000001.tif37136 Patent Document 2 describes a resist composition containing, as an acid generator, a salt represented by the following formula. TIFF0007704517000002.tif3858 Patent Document 3 describes a resist composition containing, as an acid generator, a salt represented by the following formula. TIFF0007704517000003.tif3867

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a salt capable of producing better line edge roughness (LER) than a resist pattern formed from a resist composition containing the above salt.

Means for Solving the Problems

[0005] The present invention includes the following inventions. [1] A salt represented by formula (I). TIFF0007704517000004.tif2685[In formula (I), L 1 represents a trivalent group represented by the formula (L 1 -1X). TIFF0007704517000005.tif3539(In the formula (L 1 -1X), X 0X , X 1X and X 2X each independently represent a divalent aliphatic hydrocarbon group having 1 to 48 carbon atoms, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 -. However, in each of X 0X , X 1X and X 2X , at least one of -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, -CO- or -NR 3 -. *0 represents a bond to a carbon atom of the benzene ring. *1 represents a bond to R 1 . *2 represents a bond to R 2 . R L represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.) R 1 and R 2 each independently represent a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. n represents an integer of any one of 1 to 3. When n is 2 or 3, a plurality of L 1 , a plurality of R 1 and a plurality of R 2 may be the same or different. Z + represents an organic cation. ] [2]L 1 is the formula (L 1-1), formula (L 1 -2) or a trivalent group represented by formula (L 1 -3) as described in [1]. TIFF0007704517000006.tif42144[In formula (L 1 -1), formula (L 1 -2) and formula (L 1 -3), X 0 represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 14 carbon atoms, or a group represented by formula (a-1). TIFF0007704517000007.tif1393(In formula (a-1), s represents 0 or 1. X 10 and X 11 each independently represent -O-**, -CO-**, -CO-O-**, or -O-CO-**. ** represents a bond to A 11 or A 12 represents a bond to A. A 10 and A 11 each independently represent a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. A 12 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. * represents a bond to the carbon atom to which R L is attached.) X 1 is -O-*1, -NR 3 -*1, -O-CO-*1, -O-CH2-*1, -O-CH2-CO-O-*1, or -NR 3 -CH2-*1. *1 represents a bond to R 1 represents a bond to R. X 2 is -O-*2, -NR 3 -*2, -O-CO-*2, -O-CH2-*2, -O-CH2-CO-O-*2, or -NR 3 -CH2-*2. *2 represents a bond to R 2 represents a bond to R. X 3 is -O-*1, -NR 3 -*1, -O-CH2-CO-O-*1, or -O-CH2-CO-NR3 - represents *1. *1 is R 1 and represents a bond. X 4 is -O-*2, -NR 3 -*2, -O-CH2-CO-O-*2 or -O-CH2-CO-NR 3 -*2. *2 is R 2 and represents a bond. X 5 is -O-*1, -NR 3 -*1, -O-CO-*1, -O-CH2-*1 or -NR 3 -CH2-*1. *1 is R 1 and represents a bond. X 6 is -O-*2, -NR 3 -*2, -O-CO-*2, -O-CH2-*2 or -NR 3 -CH2-*2. *2 is R 2 and represents a bond. *0 represents a bond with a carbon atom of the benzene ring. m1, m2, m3, m4 and m5 each independently represent an integer from 0 to 6. R L represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. [3] The salt according to [1] or [2], wherein n is 1 or 2. [4] R 1 and R 2 are a group represented by formula (1R) or an alicyclic hydrocarbon group having 3 to 20 carbon atoms having a fluorine atom (provided that -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). The salt according to any one of [1] to [3]. TIFF0007704517000008.tif1860 [In formula (1R), ring W represents a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms. R represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a group combining these. * represents a bonding site. An acid generator containing a salt according to any one of [1] to [4]. A resist composition containing the acid generator according to [5]. The resist composition according to [6], further containing a resin containing a structural unit having an acid-labile group. The resist composition according to [7], wherein the structural unit having an acid-labile group contains at least one selected from the group consisting of a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2). TIFF0007704517000009.tif4497[In formula (a1-1) and formula (a1-2), L a1 and L a2 each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents an integer of any one of 1 to 7, and * represents a bonding site with -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 alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these. m1 represents an integer of any one of 0 to 14. n1 represents an integer of any one of 0 to 10. n1’ represents an integer of any one of 0 to 3.] The resist composition according to [7] or [8], wherein the resin containing a structural unit having an acid-labile group contains a structural unit represented by formula (a2-A). TIFF0007704517000010.tif4755[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 a51represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a50 is a single bond or * -X a51 -(A a52 -X a52 ) nb - represents, and * represents the bonding site with the carbon atom to which -R a50 is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents any integer from 0 to 4. When mb is any integer of 2 or more, a plurality of R a51 may be the same as or different from each other. A resist composition according to any one of [6] to [9], further containing a salt that generates an acid having a lower acidity than the acid generated from the

[10] acid generator.

[11] (1) A step of applying the resist composition according to any one of [6] to

[10] on a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, which is a method for manufacturing a resist pattern.

Effects of the Invention

[0006] By using the resist composition containing the salt of the present invention, a resist pattern can be manufactured with good line edge roughness (LER).

Modes for Carrying Out the Invention

[0007] In this specification, the term "(meth)acrylic monomer" means at least one selected from the group consisting of monomers having the structure of "CH2=CH-CO-" and monomers having the structure of "CH2=C(CH3)-CO-". Similarly, "(meth)acrylate" and "(meth)acrylic acid" mean at least one selected from the group consisting of "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. Further, among the groups described in this specification, those that can take both a linear structure and a branched structure may be either of them. "Derived from" or "derived" means that the polymerizable C=C bond contained in the molecule becomes a -C-C- group by polymerization. The "combined group" means a group formed by combining two or more of the exemplified groups after appropriately changing their valences. When stereoisomers exist, all stereoisomers are included. In this specification, the "solid content of the resist composition" means the total of the components excluding the solvent (E) described later from the total amount of the resist composition.

[0008] <Salt represented by formula (I)> The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)"). Among salts (I), the side having a negative charge may be referred to as "anion (I)", and the side having a positive charge may be referred to as "cation (I)". TIFF0007704517000011.tif2684[In formula (I), L 1 represents a trivalent group represented by formula (L 1 -1X). TIFF0007704517000012.tif3438(In formula (L 1 -1X), X 0X 、X 1X and X 2Xeach independently represents a divalent aliphatic hydrocarbon group having 1 to 48 carbon atoms, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 -. However, in each of X 0X , X 1X and X 2X , at least one of -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, -CO- or -NR 3 -. *0 represents a bond with a carbon atom of the benzene ring. *1 represents a bond with R 1 . *2 represents a bond with R 2 . R L represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ) R 1 and R 2 each independently represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. n represents any integer from 1 to 3. When n is 2 or 3, a plurality of L 1 , a plurality of R 1 and a plurality of R 2 may be the same or different. Z + represents an organic cation. ]

[0009] X 0X , X 1X and X 2X Examples of the divalent aliphatic hydrocarbon group in include divalent chain hydrocarbon groups such as alkanediyl groups, and monocyclic or polycyclic (including spiro rings) divalent alicyclic hydrocarbon groups. A group formed by combining two or more of these groups (for example, a divalent hydrocarbon group formed from an alicyclic hydrocarbon group and an alkanediyl group) may also be used. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 42, more preferably 1 to 36, still more preferably 1 to 30, even more preferably 1 to 24, still even more preferably 1 to 18, and even still more preferably 1 to 12. Examples of the monocyclic or polycyclic divalent alicyclic hydrocarbon group include the following groups. The bonding hands can be at any position. TIFF0007704517000013.tif41165Specifically, monocyclic divalent alicyclic hydrocarbon groups which are cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; and polycyclic divalent alicyclic hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 42, more preferably 3 to 36, still more preferably 3 to 30, even more preferably 3 to 24, still even more preferably 3 to 18, and even still more preferably 3 to 12. Examples of a group formed by combining two or more groups include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more alicyclic hydrocarbon groups and two or more chain hydrocarbon groups may be combined respectively. Further, any group may be bonded to a carbon atom of the benzene ring, R 1 or R 2 . Examples of a group formed by combining an alicyclic hydrocarbon group and an alkanediyl group include, for example, -divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-, etc.

[0010] X 0X is preferably a divalent aliphatic hydrocarbon group having 1 to 42 carbon atoms (wherein -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 -. However, at least one of -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, -CO- or -NR 3 -), more preferably a divalent aliphatic hydrocarbon group having 1 to 42 carbon atoms (wherein -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 -. However, at least one of -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-), even more preferably a divalent aliphatic hydrocarbon group having 2 to 42 carbon atoms (wherein -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 -. However, at least one of -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, and at least one of -CH2- contained in the aliphatic hydrocarbon group is replaced by -CO-), still more preferably a divalent aliphatic hydrocarbon group having 2 to 24 carbon atoms (wherein -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3- may be replaced therewith. However, at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -O-, and at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -CO-. It is more preferable that it is). X 1X and X 2X are each independently a divalent aliphatic hydrocarbon group having 1 to 36 carbon atoms (the -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 - may be replaced therewith. However, at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -O-, -CO- or -NR 3 -. It is preferable that it is), a divalent aliphatic hydrocarbon group having 1 to 36 carbon atoms (the -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 - may be replaced therewith. However, at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -O-. It is more preferable that it is), a divalent aliphatic hydrocarbon group having 2 to 36 carbon atoms (the -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 - may be replaced therewith. However, at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -O-, and at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -CO-. It is further preferable that it is), a divalent aliphatic hydrocarbon group having 2 to 18 carbon atoms (the -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -CO- or -NR 3 - may be replaced therewith. However, at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -O-, and at least one of the -CH2- groups contained in the aliphatic hydrocarbon group is replaced by -CO-. It is more preferable that it is).

[0011] R L Examples of the aliphatic hydrocarbon group having 1 to 14 carbon atoms for include chain hydrocarbon groups such as alkyl groups, alicyclic hydrocarbon groups, and groups formed by combining these. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alicyclic saturated hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 3 to 10, and still more preferably 3 to 8. R L is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, still more preferably a hydrogen atom or a methyl group, and even more preferably a hydrogen atom. R 3 Examples of the alkyl group having 1 to 6 carbon atoms of R include a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R 3 is preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.

[0012] L 1 is preferably a trivalent group represented by formula (L 1 -1), formula (L 1 -2) or formula (L 1 -3). TIFF0007704517000014.tif42144[In formula (L 1 -1), formula (L 1 -2) and formula (L 1 -3), X 0 represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 14 carbon atoms or a group represented by formula (a-1). TIFF0007704517000015.tif1393(In formula (a-1), s represents 0 or 1. X 10 and X 11 each independently represents -O-**, -CO-**, -CO-O-** or -O-CO-**. ** represents a bond to A 11 or A 12 represents a bond to A A 10 and A 11 each independently represents a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. A 12 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. * represents a bond to the carbon atom to which R L is attached.) X 1 is -O-*1, -NR 3 -*1, -O-CO-*1, -O-CH2-*1, -O-CH2-CO-O-*1 or -NR 3 -CH2-*1. *1 represents a bond to R 1 represents a bond to R X 2 is -O-*2, -NR 3 -*2, -O-CO-*2, -O-CH2-*2, -O-CH2-CO-O-*2 or -NR 3 -CH2-*2. *2 represents a bond to R 2 represents a bond to R X 3 is -O-*1, -NR 3 -*1, -O-CH2-CO-O-*1 or -O-CH2-CO-NR 3 -*1. *1 represents a bond to R 1 represents a bond to R X 4 is -O-*2, -NR 3 -*2, -O-CH2-CO-O-*2 or -O-CH2-CO-NR 3 -*2. *2 represents a bond to R 2 represents a bond to R X 5 is -O-*1, -NR 3 -*1, -O-CO-*1, -O-CH2-*1 or -NR 3 -CH2-*1. *1 represents a bond to R 1 represents a bond to R X 6 represents -O-*2, -NR 3 -*2, -O-CO-*2, -O-CH2-*2 or -NR 3 -CH2-*2. *2 represents a bond with R 2 and. *0 represents a bond with a carbon atom of the benzene ring. m1, m2, m3, m4 and m5 each independently represent an integer of any one of 0 to 6. R L represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

[0013] X 0 , A 10 , A 11 and A 12 Examples of the divalent aliphatic hydrocarbon group in include those similar to those exemplified by X 0X , X 1X and X 2X . X 10 and X 11 each independently preferably represent -O-**, -CO-O-** or -O-CO-**, more preferably -O-** or -CO-O-**. ** represents a bond with A 11 or A 12 and. A 10 and A 11 each independently preferably represent an alkanediyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms. A 12 preferably represents a single bond, an alkanediyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms. s is preferably 0. X 0is preferably a single bond, an alkanediyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or a group represented by the formula (a-1), more preferably a single bond, an alkanediyl group having 1 to 6 carbon atoms, an alkanediyl group having 1 to 6 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms -O-*, an alkanediyl group having 1 to 6 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms -CO-O-*, an alkanediyl group having 1 to 6 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms -CO-O- an alkanediyl group having 1 to 6 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms -*. * is R L represents a bond to the carbon atom to which L is attached. X 1 is preferably -O-*1, -O-CO-*1, -O-CH2-*1 or -O-CH2-CO-O-*1. *1 is R 1 represents a bond to 1 . X 2 is preferably -O-*2, -O-CO-*2, -O-CH2-*2 or -O-CH2-CO-O-*2. *2 is R 2 represents a bond to 2 . X 3 is preferably -O-*1, -O-CH2-CO-O-*1 or -O-CH2-CO-NR 3 -*1, more preferably -O-*1 or -O-CH2-CO-O-*1. *1 is R 1 represents a bond to 1 . X 4 is preferably -O-*2, -O-CH2-CO-O-*2 or -O-CH2-CO-NR 3 -*2, more preferably -O-*2 or -O-CH2-CO-O-*2. *2 is R 2 represents a bond to 2 . X 5 is preferably -O-*1, -O-CO-*1 or -O-CH2-*1. *1 is R 1 represents a bond to 1 . X 6 is preferably -O-*2, -O-CO-*2 or -O-CH2-*2. *2 is R 2 represents a bond to 2 . m1, m2, m3, m4, and m5 are each independently preferably an integer from 0 to 5, more preferably an integer from 0 to 4, and even more preferably an integer from 0 to 3. L 1 is preferably a group represented by formula (L 1 -1) or formula (L 1 -2), and more preferably a group represented by formula (L 1 -2). L 1 The bonding position on the benzene ring of may be any of the ortho, meta, and para positions with respect to the bonding position of the sulfur atom. Among them, it is preferably bonded to the para or meta position with respect to the bonding position of the sulfur atom. When n is 1, the bonding position on the benzene ring of L 1 is preferably bonded to the para position with respect to the bonding position of the sulfur atom. When n is 2, the bonding position on the benzene ring of L 1 is preferably bonded to the meta position with respect to the bonding position of the sulfur atom.

[0014] Examples of the trivalent group represented by formula (L 1 -1) include the following. TIFF0007704517000016.tif220163

[0015] Examples of the trivalent group represented by formula (L 1 -2) include the following. TIFF0007704517000017.tif204167

[0016] Examples of the trivalent group represented by formula (L 1 -3) include the following. TIFF0007704517000018.tif176163

[0017] R 1 and R 2Examples of the hydrocarbon group 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 formed by combining these groups. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, and the like. Examples of the alkenyl group include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octynyl group, isooctynyl group, nonenyl group, and the like. Examples of the alkynyl group include ethynyl group, propynyl group, isopropynyl group, butynyl group, isobutynyl group, tert-butynyl group, pentynyl group, hexynyl group, octynyl group, nonynyl group, and the like. The number of carbon atoms in the chain hydrocarbon group is preferably from 1 to 18, more preferably from 1 to 12, still more preferably from 1 to 9, even more preferably from 1 to 6, and even more preferably from 1 to 4. The alicyclic hydrocarbon group may be either monocyclic or polycyclic (including spiro rings), and may be either saturated or unsaturated. Examples of the monocyclic alicyclic hydrocarbon group include the following groups. The bonding position can be arbitrary. TIFF0007704517000019.tif42165Specifically, monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group, and the like can be mentioned. Examples of the polycyclic alicyclic hydrocarbon group include polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group, and the like. The number of carbon atoms in the alicyclic hydrocarbon group is preferably from 3 to 18, more preferably from 3 to 16, and still more preferably from 3 to 12. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, biphenyl group, anthryl group, phenanthryl group, and binaphthyl group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and even more preferably 6 to 10. In the case of the combined group, groups having different valences in the above-mentioned groups (such as alkanediyl group, alkanetriyl group, cycloalkanediyl group, cycloalkanetriyl group, etc.) may be included. Examples of the group formed by combination include a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (for example, aromatic hydrocarbon group - alkanediyl group - *, alkyl group - aromatic hydrocarbon group - *), a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group (for example, alicyclic hydrocarbon group - alkanediyl group - *, alkyl group - alicyclic hydrocarbon group - *), and a group formed by combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (for example, aromatic hydrocarbon group - alicyclic hydrocarbon group - *, alicyclic hydrocarbon group - aromatic hydrocarbon group - *). * represents a bonding site. Examples of the aromatic hydrocarbon group - alkanediyl group - * include aralkyl groups such as benzyl group and phenethyl group. Examples of the alkyl group - aromatic hydrocarbon group - * include tolyl group, xylyl group, cumenyl group, etc. Examples of the alicyclic hydrocarbon group - alkanediyl group - * include cycloalkylalkyl groups such as cyclohexylmethyl group, cyclohexylethyl group, 1-(adamantan-1-yl)methyl group, and 1-(adamantan-1-yl)-1-methylethyl. Examples of the alkyl group - alicyclic hydrocarbon group - * include cycloalkyl groups having an alkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, and 2-alkyladamantan-2-yl group. Examples of the aromatic hydrocarbon group - alicyclic hydrocarbon group - * include phenyladamantyl group, etc. Examples of the alicyclic hydrocarbon group - aromatic hydrocarbon group - * include adamantylphenyl group, etc. In the combination, the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may each be combined with two or more thereof. Also, any group may be bonded to L 1 . When -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO-, the carbon number before replacement is defined as the total carbon number of the hydrocarbon group. Also, the number may be one or two or more. Examples of the group in which -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- contained in the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), an alkoxy group (a group in which -CH2- at any position contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -CO-O-), an alkanedioxy group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -CO-O-), an alkylthio group (a group in which -CH2- at any position contained in the alkyl group is replaced by -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, an aromatic hydrocarbon group-carbonyl-oxy group, a group formed by combining two or more of these groups, and the like. Examples of the alkoxy group include alkoxy groups having 1 to 17 carbon atoms, such as methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, undecyloxy group and the like. The alkoxycarbonyl group, alkylcarbonyl group and alkylcarbonyloxy group represent groups in which a carbonyl group or a carbonyloxy group is bonded to the above-described alkyl group or alkoxy group. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 17 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 18 carbon atoms, such as acetyl group, propionyl group and butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 17 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkanediyl-oxy group include alkanediyl-oxy groups having 1 to 17 carbon atoms, such as methyleneoxy group, ethyleneoxy group, propanediyl-oxy group, butanediyl-oxy group, pentanediyl-oxy group and the like. Examples of the alkanediyl-oxycarbonyl group include alkanediyl-oxycarbonyl groups having 2 to 17 carbon atoms, such as methyleneoxycarbonyl group, ethyleneoxycarbonyl group, propanediyl-oxycarbonyl group, butanediyl-oxycarbonyl group and the like. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 18 carbon atoms, such as methylenecarbonyl group, ethylenecarbonyl group, propanediylcarbonyl group, butanediylcarbonyl group, pentanediylcarbonyl group and the like. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 17 carbon atoms, such as methylenecarbonyloxy group, ethylenecarbonyloxy group, propanediylcarbonyloxy group, butanediylcarbonyloxy group and the like. Examples of the alkylthio group include alkylthio groups having 1 to 17 carbon atoms, such as methylthio group, ethylthio group, propylthio group and the like. Examples of the cycloalkoxy group include cycloalkoxy groups having 3 to 17 carbon atoms, such as cyclohexyloxy group and the like. Examples of the cycloalkylalkoxy group include cycloalkylalkoxy groups having 4 to 17 carbon atoms, such as cyclohexylmethoxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 16 carbon atoms, such as butoxycarbonyloxy group and the like. Examples of the aromatic hydrocarbon group-carbonyl-oxy group include aromatic hydrocarbon group-carbonyl-oxy groups having 7 to 17 carbon atoms, such as benzoyloxy group and the like. In addition, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups and the like. The bond can be at any position. TIFF0007704517000020.tif46156

[0018] R 1 and R 2 Examples of the substituent that the hydrocarbon group of may have include a halogen atom, a cyano group, an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O-, -S-, -CO- or -SO2-), and an alicyclic hydrocarbon group having 3 to 20 carbon atoms (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. 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, a nonyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 9, more preferably 1 to 6, and still more preferably 1 to 4. When -CH2- contained in an alkyl group is replaced by -O-, -S-, -CO- or -SO2- as a substituent, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the alkyl group. Examples of the group in which -CH2- contained in an alkyl group is replaced by -O-, -S-, -CO- or -SO2- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), and the like. Examples of the alkoxy group include an alkoxy group having 1 to 11 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group and the like. The alkoxycarbonyl group, the alkylcarbonyl group and the alkylcarbonyloxy group represent a group in which a carbonyl group or a carbonyloxy group is bonded to the above-described alkyl group or alkoxy group. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 11 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group, etc. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 12 carbon atoms, such as acetyl group, propionyl group, butyryl group, etc. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 11 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group, etc. Examples of the alkylthio group include alkylthio groups having 1 to 11 carbon atoms, such as methylthio group, ethylthio group, propylthio group, etc. Examples of the alicyclic hydrocarbon group having 3 to 20 carbon atoms include the following groups. The bonding position can be arbitrary. TIFF0007704517000021.tif42165Specifically, monocyclic alicyclic hydrocarbon groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group, etc., polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl group, adamantyl group, norbornyl group, etc. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and still more preferably 3 to 12. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. The bonding position can be arbitrary. TIFF0007704517000022.tif46156R 1 and R 2 The hydrocarbon group in and R may have one substituent or a plurality of substituents.

[0019] R 1 and R 2is preferably an alkyl group having 1 to 12 carbon atoms which may have a substituent (provided that -CH2- contained in the alkyl group may be replaced by -O-, -S-, -CO- or -SO2-), or a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), more preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a fluorine atom, a hydroxy group or a group combining these (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), and even more preferably an alicyclic hydrocarbon group having 3 to 20 carbon atoms having an alkyl group having 1 to 8 carbon atoms or a fluorine atom.

[0020] Examples of the cyclic hydrocarbon group include cyclic hydrocarbon groups such as monocyclic or polycyclic alicyclic hydrocarbon groups having 3 to 20 carbon atoms and aromatic hydrocarbon groups having 6 to 20 carbon atoms, or groups combining these.

[0021] Examples of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups combining these include the same groups as those described above.

[0022] Examples of the cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) include preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a fluorine atom, a hydroxy group or a group combining these (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), An alicyclic hydrocarbon group having 3 to 20 carbon atoms, which may have an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a fluorine atom, a hydroxy group or a group combining these (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or, More preferably, it is an aromatic hydrocarbon group having 6 to 20 carbon atoms, which may have an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a fluorine atom, a hydroxy group or a group combining these.

[0023] Among them, R 1 and R 2 are more preferably a group represented by the formula (1R) or an alicyclic hydrocarbon group having 3 to 20 carbon atoms having a fluorine atom (however, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). TIFF0007704517000023.tif1860 [In the formula (1R), ring W represents a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms. R represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms or a group combining these. * represents a bonding site.] Examples of the non-aromatic hydrocarbon ring of ring W include the same as those exemplified for the monocyclic, polycyclic, partially saturated and unsaturated alicyclic hydrocarbon groups in R 1 and R 2 The alkyl group, alicyclic hydrocarbon group and the group combining these in R include the same as those exemplified in R and R 1 and R 2 Examples of the group represented by the formula (1R) include the groups represented below.

[0024] Examples of the group represented by the formula (1R) include the groups represented below. TIFF0007704517000024.tif36160

[0025] n is preferably 1 or 2, more preferably 2.

[0026] Examples of the anion (I) include anions represented by the following formulas (Ia-1) to (Ia-39). Among them, anions represented by formulas (Ia-1) to (Ia-18), formula (Ia-25), formula (Ia-26), formula (Ia-32), and formula (Ia-33) are preferred, and anions represented by formula (Ia-1), formula (Ia-3), formula (Ia-5) to (Ia-7), formula (Ia-9), formula (Ia-11), formula (Ia-13), formula (Ia-15), formula (Ia-17), formula (Ia-25), and formula (Ia-32) are more preferred. JPEG0007704517000025.jpg226151

[0027] TIFF0007704517000026.tif181140

[0028] TIFF0007704517000027.tif63146

[0029] TIFF0007704517000028.tif118139

[0030] TIFF0007704517000029.tif116146

[0031] TIFF0007704517000030.tif167163

[0032] TIFF0007704517000031.tif61146

[0033] TIFF0007704517000032.tif190153

[0034] TIFF0007704517000033.tif130140

[0035] Z +Examples of the organic cation include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, organic phosphonium cations, and the like. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations are more preferred. Specifically, cations represented by any of formula (b2-1) to formula (b2-4) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number) are included.

[0036] In TIFF0007704517000034.tif47167, in formula (b2-1) to formula (b2-4), R b4 ~R b6 each independently represents a linear hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the linear hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S-, or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of 0 to 5. When m2 is 2 or more, a plurality of R b7 may be the same or different, and when n2 is 2 or more, a plurality of Rb8 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 combine with each other to form a ring together with the sulfur atom to which they are attached, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the chain hydrocarbon group may be substituted by an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted by an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may combine with each other to form a ring including -CH-CO- to which they are attached, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 each independently represents a hydroxy group, a 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 represents any integer from 0 to 5. q2 and r2 each independently represents any integer from 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, the plurality of R b13 are the same or different, when p2 is 2 or more, the plurality of R b14 are the same or different, when q2 is 2 or more, the plurality of Rb15 are the same or different, and when r2 is 2 or more, a plurality of R b16 are the same or different, and when s2 is 2 or more, a plurality of R b17 are the same or different, and when t2 is 2 or more, a plurality of R b18 are the same or different.

[0037] The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, and 2-ethylhexyl group. In particular, R b9 ~R b12 The chain hydrocarbon group preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups. TIFF0007704517000035.tif10158 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

[0038] Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include methylcyclohexyl group, dimethylcyclohexyl group, 2-methyladamantan-2-yl group, 2-ethyladamantan-2-yl group, 2-isopropyladamantan-2-yl group, methylnorbornyl group, isobornyl group, etc. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less.

[0039] Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, biphenyl group, naphthyl group, and phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples of the aromatic hydrocarbon group having a chain hydrocarbon group include tolyl group, xylyl group, cumenyl group, mesityl group, p-ethylphenyl group, p-tert-butylphenyl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc., and examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group include p-cyclohexylphenyl group, p-adamantylphenyl group, etc. When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferable. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include p-methoxyphenyl group, etc. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as benzyl group, phenethyl group, phenylpropyl group, trityl group, naphthylmethyl group, naphthylethyl group, etc.

[0040] Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group, and dodecyloxy group, etc. Examples of the alkylcarbonyl group include acetyl group, propionyl group, and butyryl group, etc. Examples of the halogen atom include fluorine atom, chlorine atom, bromine atom, and iodine atom, etc. Examples of the alkylcarbonyloxy group include methylcarbonyloxy group, ethylcarbonyloxy group, propylcarbonyloxy group, isopropylcarbonyloxy group, butylcarbonyloxy group, sec-butylcarbonyloxy group, tert-butylcarbonyloxy group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyloxy group, and 2-ethylhexylcarbonyloxy group, etc.

[0041] Rb4 and R b5 The ring formed by the combination of and together with the sulfur atom to which they are attached 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, preferably rings having 4 to 18 carbon atoms. In addition, examples of the ring containing a sulfur atom include 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings, and examples include the following rings. * represents a bond. TIFF0007704517000036.tif23143

[0042] R b9 and R b10 The ring formed by and together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include thiolan-1-ium ring (tetrahydrothiophenium ring), thian-1-ium ring, 1,4-oxathian-4-ium ring, etc. R b11 and R b12 The ring formed by and together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring, etc.

[0043] Among cations (b2-1) to (b2-4), preferably, it is cation (b2-1). Examples of cation (b2-1) include the following cations. TIFF0007704517000037.tif81158

[0044] TIFF0007704517000038.tif74165

[0045] Examples of cation (b2-2) include the following cations. TIFF0007704517000039.tif18150

[0046] Examples of the cation (b2-3) include the following cations. TIFF0007704517000040.tif26140

[0047] Examples of the cation (b2-4) include the following cations. TIFF0007704517000041.tif82165

[0048] The salt (I) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. As the salt (I), preferably, an anion represented by any of Formula (Ia-1) to Formula (Ia-18), Formula (Ia-25), Formula (Ia-26), Formula (Ia-32), and Formula (Ia-33), and a combination with the cation (b2-1), the cation (b2-2), or the cation (b2-3) are exemplified.

[0049] Examples of the salt (I) include the salts described in Table 1. In the following table, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation. For example, the salt (I-1) means a salt composed of an anion represented by Formula (Ia-1) and a cation represented by Formula (b2-c-1), and represents the following salts. TIFF0007704517000042.tif69127 [Table 1] TIFF0007704517000044.tif223154 TIFF0007704517000045.tif223154 TIFF0007704517000046.tif192155

[0050] Among them, the salt (I) is preferably the salt (I-1), salt (I-3), salt (I-5) to salt (I-7), salt (I-9), salt (I-11), salt (I-13), salt (I-15), salt (I-17), salt (I-19), salt (I-21), salt (I-23) to salt (I-25), salt (I-27), salt (I-29), salt (I-31), salt (I-33), salt (I-35), salt (I-37), salt (I-39), salt (I-41) to salt (I-43), salt (I-45), salt (I-47), salt (I-49), salt (I-51), salt (I-53), salt (I-55), salt (I-57), salt (I-59), salt (I-51), salt (I-53), salt (I-55), salt (I-57), salt (I-59) to salt (I-61), salt (I-63), salt (I-65), salt (I-67), salt (I-69), salt (I-71), salt (I-73), salt (I-75), salt (I-77) to salt (I-79), salt (I-81), salt (I-83), salt (I-85), salt (I-87), salt (I-89), salt (I-91), salt (I-93), salt (I-95) to salt (I-97), salt (I-99), salt (I-101), salt (I-103), salt (I-105), salt (I-107), salt (I-109), salt (I-111), salt (I-113) to salt (I-115), salt (I-117), salt (I-119), salt (I-121), salt (I-123), salt (I-125), salt (I-127), salt (I-129), salt (I-131), salt (I-133), salt (I-135), salt (I-137), salt (I-139), salt (I-141), salt (I-143), salt (I-145), salt (I-147), salt (I-149), salt (I-151), salt (I-153).

[0051] <Method for producing salt (I)> In the salt (I), L 1 is a trivalent group represented by the formula (L 1 -1), and the salt represented by the formula (I1) can be produced, for example, by reacting the salt represented by the formula (I1-a) with carbonyldiimidazole in a solvent and then further reacting with the compound represented by the formula (I1-b). TIFF0007704517000047.tif43157 (In the formula, all the symbols have the same meanings as described above.)

[0052] Examples of the solvent include chloroform, dimethylformamide, and acetonitrile. The reaction temperature is usually from 10°C to 80°C, and the reaction time is usually from 0.5 hour to 24 hours.

[0053] Examples of the salt represented by formula (I1-a) include salts represented below, and they can be easily obtained from the market. TIFF0007704517000048.tif73148

[0054] Examples of the compound represented by formula (I1-b) include compounds represented below, and they can be easily obtained from the market and can also be easily produced by known production methods. TIFF0007704517000049.tif28160

[0055] In salt (I), L 1 is a trivalent group represented by formula (L 1 -2) (the salt represented by formula (I2)) can be produced, for example, by reacting the salt represented by formula (I1-a) with carbonyldiimidazole in a solvent and then further reacting with the compound represented by formula (I2-b). TIFF0007704517000050.tif46155 (In the formula, all symbols have the same meanings as described above.)

[0056] Examples of the solvent include chloroform, dimethylformamide, and acetonitrile. The reaction temperature is usually from 10°C to 80°C, and the reaction time is usually from 0.5 hour to 24 hours.

[0057] Examples of the compound represented by formula (I2-b) include compounds represented below, and they can be easily obtained from the market and can also be easily produced by known production methods. TIFF0007704517000051.tif108155

[0058] In salt (I), L 1 is a trivalent group represented by formula (L 1 -3), and the salt represented by formula (I3) can be produced, for example, by reacting a compound represented by formula (I3-b) with carbonyldiimidazole in a solvent and then further reacting with a salt represented by formula (I3-a). TIFF0007704517000052.tif45153 (wherein all the symbols have the same meanings as described above).

[0059] Examples of the solvent include chloroform, dimethylformamide, and acetonitrile. The reaction temperature is usually from 10°C to 80°C, and the reaction time is usually from 0.5 hour to 24 hours.

[0060] Examples of the salt represented by formula (I3-a) include salts represented below, and they can be produced by the method described in JP-A-2009-155304. TIFF0007704517000053.tif2543

[0061] Examples of the compound represented by formula (I3-b) include compounds represented below, and they can be easily obtained from the market and can also be easily produced by known production methods. TIFF0007704517000054.tif26119

[0062] <Acid generator> The acid generator of the present invention is an acid generator containing salt (I). It may contain one kind of salt (I) or may contain two or more kinds of salt (I). In addition to salt (I), the acid generator of the present invention may contain an acid generator known in the resist field (hereinafter sometimes referred to as "acid generator (B)"). The acid generator (B) may be used alone or in combination of two or more kinds.

[0063] The acid generator (B) may be either nonionic or ionic. Examples of nonionic acid generators include sulfonate esters (such as 2-nitrobenzyl esters, aromatic sulfonates, oxime sulfonates, N-sulfonyloxyimides, sulfonyloxy ketones, diazonaphthoquinone 4-sulfonates), sulfones (such as disulfones, ketosulfones, sulfonyldiazomethane), and the like. Representative examples of ionic acid generators include onium salts containing onium cations (such as diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of anions of onium salts include sulfonic acid anions, sulfonylimide anions, sulfonylmethide anions, and the like.

[0064] As the acid generator (B), compounds that generate acid upon irradiation, as described in, for example, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc., can be used. Also, compounds produced by known methods may be used. The acid generator (B) may be used in combination of two or more.

[0065] The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a salt represented by the formula (B1) (hereinafter sometimes referred to as "acid generator (B1)", provided that salt (I) is excluded). TIFF0007704517000055.tif3063[In the formula (B1), Q b1 and Q b2 each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. L b1represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, wherein -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group. Y represents an optionally substituted methyl group or an optionally substituted alicyclic hydrocarbon group having 3 to 24 carbon atoms, wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S(O)2- or -CO-. Z1 + represents an organic cation.

[0066] Q b1 and Q b2 Examples of the perfluoroalkyl group represented by Q and Q include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group and the like. Q b1 and Q b2 are each independently preferably a fluorine atom or a trifluoromethyl group, and more preferably both are fluorine atoms.

[0067] L b1 Examples of the divalent saturated hydrocarbon group in L include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and a group formed by combining two or more of these groups may also be used. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group; Branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; Monocyclic divalent alicyclic saturated hydrocarbon groups which are cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; Examples thereof include polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group.

[0068] L b1 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO- include groups represented by any of formula (b1-1) to formula (b1-3). In the groups represented by formula (b1-1) to formula (b1-3) and the groups represented by formula (b1-4) to formula (b1-11) which are specific examples thereof, * represents a bond to -Y.

[0069] TIFF0007704517000056.tif26118[In formula (b1-1), L b2represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L b2 and L b3 have a total carbon number of 22 or less. In formula (b1-2), L b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L b4 and L b5 have a total carbon number of 22 or less. In formula (b1-3), L b6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups. L b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms or hydroxy groups, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. However, L b6 and L b7 have a total carbon number of 23 or less. * and ** represent bonds, and * represents the bond with Y.

[0070] In the groups represented by formulas (b1-1) to (b1-3), when -CH2- contained in the saturated hydrocarbon group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the saturated hydrocarbon group. Examples of the divalent saturated hydrocarbon group include those similar to the divalent saturated hydrocarbon group of L b1 as defined below. L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and a hydrogen atom contained in the divalent saturated hydrocarbon group may be replaced by 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 replaced by 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 replaced by a fluorine atom or a hydroxy group, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O- or -CO-.

[0071] L b1 As the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by the formula is replaced by -O- or -CO-, the group represented by the formula (b1-1) or the formula (b1-3) is preferable. Examples of the group represented by the formula (b1-1) include the groups represented by the formulas (b1-4) to (b1-8), respectively. TIFF0007704517000057.tif48120 [In the 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 replaced by 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 replaced by a fluorine atom or a hydroxy group. However, the total number of carbon atoms of L b9 and L b10 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 replaced by a fluorine atom or a hydroxy group. However, the total number of carbon atoms of L b11 and L b12 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 by -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 replaced by a fluorine atom or a hydroxy group. However, the total number of carbon atoms of L b13 ~L b15 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 b17represents 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. * and ** represent bonds, and * represents a bond with Y. L b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, more preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0072] Examples of the group represented by formula (b1-3) include groups represented by formula (b1-9) to formula (b1-11). TIFF0007704517000058.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 b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, the total number of carbon atoms of L b19 and L b20 is 23 or less. In formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a fluorine atom, a hydroxy group, or an alkylcarbonyloxy group. -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and a hydrogen atom contained in the alkylcarbonyloxy group may be substituted with a hydroxy group. However, the total number of carbon atoms of L b21 , L b22 and L b23 is 21 or less. In formula (b1-11), L b24represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the hydrogen atoms contained in the saturated hydrocarbon group may be substituted with fluorine atoms, hydroxy groups or alkylcarbonyloxy groups. The -CH2- contained in the alkylcarbonyloxy group may be replaced with -O- or -CO-, and the hydrogen atoms contained in the alkylcarbonyloxy group may be substituted with hydroxy groups. However, L b24 L b25 and L b26 have a total carbon number of 21 or less. * and ** represent bonds, and * represents the bond to Y.

[0073] In the group represented by the formula (b1-9) to the group represented by the formula (b1-11), when the hydrogen atoms contained in the saturated hydrocarbon group are substituted with alkylcarbonyloxy groups, the carbon number before substitution is defined as the carbon number of the saturated hydrocarbon group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, a cyclohexylcarbonyloxy group, an adamantylcarbonyloxy group, and the like.

[0074] Examples of the group represented by the formula (b1-4) include the following. TIFF0007704517000059.tif16150 (* and ** represent bonds, and * represents the bond to Y.)

[0075] Examples of the group represented by the formula (b1-5) include the following. TIFF0007704517000060.tif72148 (* and ** represent bonds, and * represents the bond to Y.)

[0076] Examples of the group represented by formula (b1-6) include the following. TIFF0007704517000061.tif29150 (* and ** represent bonds, and * represents the bond to Y.)

[0077] Examples of the group represented by formula (b1-7) include the following. TIFF0007704517000062.tif64150 (* and ** represent bonds, and * represents the bond to Y.)

[0078] Examples of the group represented by formula (b1-8) include the following. TIFF0007704517000063.tif23150 (* and ** represent bonds, and * represents the bond to Y.)

[0079] Examples of the group represented by formula (b1-2) include the following. TIFF0007704517000064.tif31161 (* and ** represent bonds, and * represents the bond to Y.)

[0080] Examples of the group represented by formula (b1-9) include the following. TIFF0007704517000065.tif44136 (* and ** represent bonds, and * represents the bond to Y.)

[0081] Examples of the group represented by formula (b1-10) include the following. TIFF0007704517000066.tif90157 (* and ** represent bonds, and * represents the bond to Y.)

[0082] Examples of the group represented by formula (b1-11) include the following. TIFF0007704517000067.tif82158 (* and ** represent bonds, and * represents the bond to Y.)

[0083] Examples of the alicyclic hydrocarbon group represented by Y include groups represented by formula (Y1) to formula (Y11), formula (Y36) to formula (Y38). When -CH2- contained in the alicyclic hydrocarbon group represented by Y is replaced by -O-, -S(O)2- or -CO-, the number thereof may be one or two or more. Examples of such groups include groups represented by formula (Y12) to formula (Y35), formula (Y39) to formula (Y43). * represents a bond to L b1 represents a bond to TIFF0007704517000068.tif81165 The alicyclic hydrocarbon group represented by Y is preferably a group represented by any of formula (Y1) to formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39) to formula (Y43), more preferably a group represented by formula (Y11), formula (Y15), formula (Y16), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42) or formula (Y43), and even more preferably a group represented by formula (Y11), formula (Y15), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39), formula (Y40), formula (Y42) or formula (Y43). When the alicyclic hydrocarbon group represented by Y is a spiro ring containing an oxygen atom such as formula (Y28) to formula (Y35), formula (Y39) to formula (Y40), formula (Y42) or formula (Y43), the alkanediyl group between two oxygen atoms preferably has one or more fluorine atoms. Further, among the alkanediyl groups contained in the ketal structure, the methylene group adjacent to the oxygen atom is preferably not substituted with a fluorine atom.

[0084] Examples of the substituent of the methyl group represented by Y include a halogen atom, a hydroxy group, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-O-R b1 group or -(CH2) ja -O-CO-R b1 group (wherein R b1represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, and -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 any integer from 0 to 4.) etc. can be mentioned. Examples of the substituent of the alicyclic hydrocarbon group represented by Y include a halogen atom, a hydroxy group, an alkyl group having 1 to 16 carbon atoms which may be substituted by a hydroxy group (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, a glycidyloxy group, -(CH2) ja -CO-O-R b1 group or -(CH2) ja -O-CO-R b1 group (wherein R b1 represents an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, and -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 any integer from 0 to 4.) etc. can be mentioned.

[0085] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. Examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, a dimethylcyclohexyl group, a cycloheptyl group, a cyclooctyl group, a norbornyl group, an adamantyl group, and the like. The alicyclic hydrocarbon group may have a chain hydrocarbon group, and examples thereof include a methylcyclohexyl group and a dimethylcyclohexyl group. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 3 to 10. Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples thereof include an aromatic hydrocarbon group having a chain hydrocarbon group having 1 to 18 carbon atoms (a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-methylphenyl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.), and an aromatic hydrocarbon group having an alicyclic hydrocarbon group having 3 to 18 carbon atoms (a p-adamantylphenyl group, a p-cyclohexylphenyl group, etc.). The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 14, more preferably 6 to 10. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, and the like. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alkyl group substituted with a hydroxy group include hydroxyalkyl groups such as a hydroxymethyl group and a hydroxyethyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the group in which -CH2- contained in the alkyl group is replaced by -O-, -S(O)2-, -CO- or the like include an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group or a group combining these groups. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group and a dodecyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 12, more preferably 1 to 6, and still more preferably 1 to 4. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group and a butoxycarbonyl group. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the combined group include a group combining an alkoxy group and an alkyl group, a group combining an alkoxy group and an alkoxy group, a group combining an alkoxy group and an alkylcarbonyl group, a group combining an alkoxy group and an alkylcarbonyloxy group and the like. Examples of the group combining an alkoxy group and an alkyl group include an alkoxyalkyl group such as a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group and an ethoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 12, more preferably 2 to 6, and still more preferably 2 to 4. Examples of the group formed by combining an alkoxy group and an alkoxy group include alkoxyalkoxy groups such as methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, and ethoxyethoxy group. The number of carbon atoms of the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the group formed by combining an alkoxy group and an alkylcarbonyl group include alkoxyalkylcarbonyl groups such as methoxyacetyl group, methoxypropionyl group, ethoxyacetyl group, and ethoxypropionyl group. The number of carbon atoms of the alkoxyalkylcarbonyl group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group formed by combining an alkoxy group and an alkylcarbonyloxy group include alkoxyalkylcarbonyloxy groups such as methoxyacetyloxy group, methoxypropionyloxy group, ethoxyacetyloxy group, and ethoxypropionyloxy group. The number of carbon atoms of the alkoxyalkylcarbonyloxy group is preferably 3 to 13, more preferably 3 to 7, and even more preferably 3 to 5. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S(O)2- or -CO- etc. include the groups represented by formula (Y12) to formula (Y35), formula (Y39) to formula (Y43).

[0086] Examples of Y include the following. TIFF0007704517000069.tif160165

[0087] Y is preferably an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have substituents, more preferably an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have substituents, still more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have substituents, and even more preferably an adamantyl group which may have substituents. The -CH2- constituting the alicyclic hydrocarbon group or adamantyl group may be replaced by -CO-, -S(O)2- or -CO-. Specifically, Y is preferably an adamantyl group, a hydroxyadamantyl group, an oxoadamantyl group or a group represented by formula (Y42), formula (Y100) to formula (Y114).

[0088] As the anion in the salt represented by formula (B1), anions represented by formula (B1-A-1) to formula (B1-A-59) [hereinafter, may be referred to as "anion (B1-A-1)" etc. according to the formula number] are preferable, and an anion represented by any of formula (B1-A-1) to formula (B1-A-4), formula (B1-A-9), formula (B1-A-10), formula (B1-A-24) to formula (B1-A-33), formula (B1-A-36) to formula (B1-A-40), formula (B1-A-47) to formula (B1-A-59) is more preferable.

[0089] TIFF0007704517000070.tif143153

[0090] TIFF0007704517000071.tif91157

[0091] TIFF0007704517000072.tif67158

[0092] TIFF0007704517000073.tif121153

[0093] TIFF0007704517000074.tif57162

[0094] TIFF0007704517000075.tif186166 Here, R i2 ~R i7are, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, a chain hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 represent the same meaning as described above. Specific examples of the anion in the salt represented by the formula (B1) include the anions described in JP-A-2010-204646.

[0095] Preferred examples of the anion in the salt represented by the formula (B1) include the anions represented by the formulas (B1a-1) to (B1a-38), respectively. JPEG0007704517000076.jpg125153

[0096] TIFF0007704517000077.tif91138

[0097] TIFF0007704517000078.tif168155

[0098] Among them, an anion represented by any one of the formulas (B1a-1) to (B1a-3), (B1a-7) to (B1a-16), (B1a-18), (B1a-19), and (B1a-22) to (B1a-38) is preferred.

[0099] Z1 + Examples of the organic cation of include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations are more preferred. As the arylsulfonium cation, Z in the formula (I)+ Those similar to the cation can be mentioned.

[0100] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. As the acid generator (B), preferably, a combination of an anion represented by any of formula (B1a-1) to formula (B1a-3), formula (B1a-7) to formula (B1a-16), formula (B1a-18), formula (B1a-19), formula (B1a-22) to formula (B1a-38) and the cation (b2-1) or the cation (b2-3) can be mentioned.

[0101] As the acid generator (B), preferably, those represented by formula (B1-1) to formula (B1-56) can be mentioned. Among them, those containing an arylsulfonium cation are preferable, and those represented by formula (B1-1) to formula (B1-3), formula (B1-5) to formula (B1-7), formula (B1-11) to formula (B1-14), formula (B1-20) to formula (B1-26), formula (B1-29), formula (B1-31) to formula (B1-56) are particularly preferable. TIFF0007704517000079.tif61150

[0102] TIFF0007704517000080.tif72163

[0103] TIFF0007704517000081.tif79150

[0104] TIFF0007704517000082.tif64150

[0105] TIFF0007704517000083.tif61145

[0106] TIFF0007704517000084.tif87153

[0107] TIFF0007704517000085.tif68167

[0108] TIFF0007704517000086.tif93158

[0109] When containing salt (I) and acid generator (B) as the acid generator, the ratio of the content of salt (I) to the content of acid generator (B) (mass ratio; salt (I): acid generator (B)) is usually 1:99 to 99:1, preferably 2:98 to 98:2, more preferably 5:95 to 95:5, still more preferably 10:90 to 90:10, and particularly preferably 15:85 to 85:15. In the resist composition of the present invention, when containing the resin (A) described later, the total content rate of the acid generator is preferably 1 part by mass or more and 45 parts by mass or less, more preferably 1 part by mass or more and 40 parts by mass or less, still more preferably 3 parts by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the resin (A). Further, when not containing the resin (A) described later, it 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 with respect to the solid content of the resist composition.

[0110] <Resist composition> The resist composition of the present invention contains an acid generator containing salt (I). The resist composition of the present invention preferably contains a resin having a structural unit having an acid-labile group (hereinafter sometimes referred to as "resin (A)"). Here, the "acid-labile group" means a group having a leaving group, and when contacted with an acid, the leaving group is eliminated and the structural unit is converted into a structural unit having a hydrophilic group (for example, a hydroxy group or a carboxy group). The resist composition of the present invention more preferably contains a quencher such as a salt that generates an acid having a lower acidity than the acid generated from the acid generator (hereinafter sometimes referred to as "quencher (C)"), and more preferably contains a solvent (hereinafter sometimes referred to as "solvent (E)").

[0111] <Resin (A)> Resin (A) has a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)"). Resin (A) preferably further contains a structural unit other than structural unit (a1). Examples of the structural unit other than structural unit (a1) include a structural unit having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)"), a structural unit other than structural unit (a1) and structural unit (s) (for example, a structural unit having a halogen atom described later (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group described later (hereinafter sometimes referred to as "structural unit (a5)"), and a structural unit derived from other monomers known in the art, etc.).

[0112] 〈Structural unit (a1)〉 Structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid-labile group contained in resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF0007704517000087.tif1988[In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, or R a1 and R a2 are bonded to each other to form a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bonding site.] TIFF0007704517000088.tif2171[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’They are bonded to each other to form a heterocyclic ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded and X, and the —CH2— contained in the hydrocarbon group and the heterocyclic ring may be replaced by —O— or —S—. X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.

[0113] R a1 、R a2 and R a3 Examples of the alkyl group in R R a1 、R a2 and R a3 include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group and the like. R a1 、R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following group (* represents a bonding site.). The carbon number of the alicyclic hydrocarbon group of R a1 、R a2 and R a3 is preferably 3 to 16. TIFF0007704517000089.tif10151R a1 、R a2 and R a3 Examples of the aromatic hydrocarbon group in include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like. Examples of the combined group include a group combining the above-described alkyl group and alicyclic hydrocarbon group (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, etc. Preferably, ma is 0 and na is 1. R a1 and R a2 When they are bonded to each other to form a non-aromatic hydrocarbon ring, examples of -C(R a1 )(R a2 )(R a3 ) include the following rings. The non-aromatic hydrocarbon ring preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-. TIFF0007704517000090.tif31138

[0114] R a1’ 、R a2’ and R a3’ Examples of the hydrocarbon group in R 、R a1 、R a2 and R a3 include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group, etc. Examples of the combined group include a group combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, and the like. R a2’ and R a3’ When R and R are bonded to each other to form a heterocyclic ring together with the carbon atom to which they are bonded and X, -C(R a1’ )(R a2’ )-X-R a3’ includes the following rings. * represents the bonding site. TIFF0007704517000091.tif19130R a1’ and R a2’ Among them, at least one is preferably a hydrogen atom. na' is preferably 0.

[0115] Examples of the group (1) include the following groups. In formula (1), a group in which R a1 , R a2 and R a3 are alkyl groups, ma = 0, and na = 1. As such a group, a tert-butoxycarbonyl group is preferable. In formula (1), a group in which R a1 , R a2 together with the carbon atom to which they are bonded form an adamantyl group, R a3 is an alkyl group, ma = 0, and na = 1. In formula (1), R a1 and R a2are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1 group. Specific examples of the group (1) include the following groups. * represents a bonding site. TIFF0007704517000092.tif171163

[0116] Specific examples of the group (2) include the following groups. * represents a bonding site. TIFF0007704517000093.tif68162

[0117] 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.

[0118] Among the (meth)acrylic monomers having an acid-labile group, those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms are preferably mentioned. If a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0119] As the structural unit derived from the (meth)acrylic monomer having the group (1), the structural unit represented by the formula (a1-0) (hereinafter sometimes referred to as the structural unit (a1-0)), the structural unit represented by the formula (a1-1) (hereinafter sometimes referred to as the structural unit (a1-1)), or the structural unit represented by the formula (a1-2) (hereinafter sometimes referred to as the structural unit (a1-2)) can be mentioned. Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF0007704517000094.tif44142[In the formula (a1-0), the formula (a1-1), and the formula (a1-2), L a01 、L a1 and L a2each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents an integer from 1 to 7, and * represents the bonding site 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, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these. m1 represents an integer from 0 to 14. n1 represents an integer from 0 to 10. n1’ represents an integer from 0 to 3.]

[0120] R a01 R a4 and R a5 are preferably methyl groups. L a01 L a1 and L a2 are preferably an oxygen atom or *-O-(CH2) k01 -CO-O- (where k01 is preferably an integer from 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 R a03 R a04 R a6 and R a7 Examples of the alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups formed by combining these in R a1 R a2 and R a3 are the same as the groups exemplified for R R a02 and R a03 and R a04 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a6 and R a7 The alkyl group in is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group or a t-butyl group, and even more preferably an ethyl group, an isopropyl group or a t-butyl group. R a6 and R a7 The alkenyl group in is preferably an alkenyl group having 2 to 6 carbon atoms, more preferably an ethenyl group, a propenyl group, an isopropenyl group or a butenyl group. R a02 and R a03 and R a04 and R a6 and R a7 The number of carbon atoms of the alicyclic hydrocarbon group of is preferably 5 to 12, and more preferably 5 to 10. R a02 and R a03 and R a04 and R a6 and R a7 The number of carbon atoms of the aromatic hydrocarbon group of is preferably 6 to 12, and more preferably 6 to 10. For the group formed by combining an alkyl group and an alicyclic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and alicyclic hydrocarbon group is 18 or less. For the group formed by combining an alkyl group and an aromatic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and aromatic hydrocarbon group is 18 or less. R a02 and R a03 are preferably an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group. R a04is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. R a6 and R a7 are each independently preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, a phenyl group or a naphthyl group, and even more preferably an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group or a phenyl group. m1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1' is preferably 0 or 1.

[0121] Examples of the structural unit (a1-0) include a structural unit represented by any of the formulas (a1-0-1) to (a1-0-18) and a structural unit in which the methyl group corresponding to R a01 in the structural unit (a1-0) is replaced by a hydrogen atom. A structural unit represented by any of the formulas (a1-0-1) to (a1-0-10), (a1-0-13), and (a1-0-14) is preferable. TIFF0007704517000095.tif99162

[0122] Examples of the structural unit (a1-1) include a structural unit derived from the monomer described in JP-A-2010-204646. Among them, a structural unit represented by any of the formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R a4 in the structural unit (a1-1) is replaced by a hydrogen atom are preferable, and a structural unit represented by any of the formulas (a1-1-1) to (a1-1-4) is more preferable. TIFF0007704517000096.tif41169

[0123] As the structural unit (a1-2), there are a structural unit represented by any one of the formulas (a1-2-1) to (a1-2-12) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced by a hydrogen atom, and a structural unit represented by any one of the formulas (a1-2-2), (a1-2-5), (a1-2-6) and (a1-2-10) to (a1-2-12) is preferred. a5 When the resin (A) contains the structural unit (a1-0), its content is usually 5 to 80 mol%, preferably 5 to 75 mol%, more preferably 10 to 70 mol% with respect to all the structural units of the resin (A). TIFF0007704517000097.tif75156

[0124] When the resin (A) contains the structural unit (a1-0), its content is usually 5 to 80 mol%, preferably 5 to 75 mol%, more preferably 10 to 70 mol% with respect to all the structural units of the resin (A). When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is usually 10 to 90 mol%, preferably 15 to 85 mol%, more preferably 20 to 80 mol%, still more preferably 20 to 75 mol%, and even more preferably 20 to 70 mol% with respect to all the structural units of the resin (A).

[0125] As the structural unit having the group (2) in the structural unit (a1), there is a structural unit represented by the formula (a1-4) (hereinafter, may be referred to as "structural unit (a1-4)"). TIFF0007704517000098.tif4564[In the formula (a1-4), R a32 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a33 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a30 represents a single bond or * -Xa31 -(A a32 -X a32 ) nc - represents, and * represents the bonding site with the carbon atom to which -R a32 is bonded. A a32 represents an alkanediyl group having 1 to 6 carbon atoms. X a31 and X a32 each independently represent -O-, -CO-O- or -O-CO-. nc represents 0 or 1. la represents any integer from 0 to 4. When la is any integer of 2 or more, a plurality of R a33 may be the same as or different from each other. R a34 and R a35 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-.

[0126] R a32 and R a33 Examples of the halogen atom in R include a fluorine atom, a chlorine atom, a bromine atom, and the like. a32 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R R a32is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a33 Examples of the alkyl group in a33 include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a33 Examples of the alkoxy group in a33 include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a33 Examples of the alkoxyalkyl group in a33 include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a33 Examples of the alkoxyalkoxy group in a33 include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. R a33 Examples of the alkylcarbonyl group in a33 include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a33Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a33 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0127] *-X a31 -(A a32 -X a32 ) nc Examples of - include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a32 -CO-O-, *-O-CO-A a32 -O-, *-O-A a32 -CO-O-, *-CO-O-A a32 -O-CO-, *-O-CO-A a32 -O-CO- are included. Among them, *-CO-O-, *-CO-O-A a32 -CO-O- or *-O-A a32 -CO-O- is preferred.

[0128] A a32 Examples of the alkanediyl group in A include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. A a32 is preferably a methylene group or an ethylene group.

[0129] Aa30 is a single bond, *-CO-O- or *-CO-O-A a32 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0130] la is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. R a34 、R a35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, etc. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, etc. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents the bonding site), etc. TIFF0007704517000099.tif10151 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a phenanthryl group, etc. Examples of the combined group include groups formed by combining the above-mentioned alkyl group and alicyclic hydrocarbon group (e.g., alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), 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.), aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. In particular, R a36 Examples of R

[0131] R a34 is preferably a hydrogen atom. R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a36 's hydrocarbon group 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. The alkyl group and alicyclic hydrocarbon group in R a36 are preferably unsubstituted. The aromatic hydrocarbon group in R a36 preferably has an aromatic ring having an aryloxy group having 6 to 10 carbon atoms. -OC(R a34 )(R a35 )-O-R a36Upon contact with an acid (e.g., p-toluenesulfonic acid), it dissociates to form a hydroxy group. -OC(R a34 )(R a35 )-O-R a36 Preferably binds to the o-position or p-position of the benzene ring, more preferably binds to the p-position.

[0132] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-18) and the structural units in which the hydrogen atom corresponding to R a32 is replaced by a methyl group are included, and more preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-5), formula (a1-4-10), formula (a1-4-13), and formula (a1-4-14) are included. TIFF0007704517000100.tif101166

[0133] When the resin (A) contains the structural unit (a1-4), its content is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 60 mol% based on the total of all the structural units of the resin (A).

[0134] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) also include the structural unit represented by formula (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)"). TIFF0007704517000101.tif4558In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. Z a1 represents a single bond or *-(CH2) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, and * is L51 Represents the binding site to L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-. s1 represents any integer from 1 to 3. s1’ represents any integer from 0 to 3.

[0135] Examples of the halogen atom include a fluorine atom and a chlorine atom, and a fluorine atom is preferred. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a fluoromethyl group, and a trifluoromethyl group. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Among them, it is preferable that one is -O- and the other is -S-. s1 is preferably 1. s1’ is preferably any integer from 0 to 2. Z a1 is preferably a single bond or *-CH2-CO-O-.

[0136] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among them, the structural units represented by formula (a1-5-1) to formula (a1-5-4) are preferable, and the structural unit represented by formula (a1-5-1) or formula (a1-5-2) is more preferable. TIFF0007704517000102.tif33133

[0137] When the resin (A) contains the structural unit (a1-5), its content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, still more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol% based on all the structural units of the resin (A).

[0138] Examples of the structural unit (a1) also include the following structural units. TIFF0007704517000103.tif31162

[0139] When the resin (A) contains structural units such as (a1-3-1) to (a1-3-7) above, its content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol% based on all the structural units of the resin (A).

[0140] Examples of the structural unit (a1) also include the following structural units. TIFF0007704517000104.tif5295 When the resin (A) contains structural units such as (a1-6-1) to (a1-6-3) above, its content is preferably 10 to 60 mol%, more preferably 15 to 55 mol%, still more preferably 20 to 50 mol%, even more preferably 20 to 45 mol%, and particularly preferably 20 to 40 mol% based on all the structural units of the resin (A).

[0141] 〈Structural unit (s)〉 The structural unit (s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer (s)"). As the monomer that leads to the structural unit (s), a monomer having no acid-labile group known in the resist field can be used. As the structural unit(s), it is preferable to have a hydroxy group or a lactone ring. If 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)") is used in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved.

[0142] 〈Structural unit (a2)〉 The hydroxy group possessed by the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group. When producing a resist pattern from the resist composition of the present invention, when using a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) as the exposure light source, as the structural unit (a2), a structural unit (a2) having a phenolic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-A) described later. Further, when using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-1) described later. The structural unit (a2) may be included alone or in two or more kinds.

[0143] Examples of the structural unit having a phenolic hydroxy group in the structural unit (a2) include a structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF0007704517000105.tif4752[In the formula (a2-A), R a50 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a50 represents a single bond or *-X a51 -(A a52 -X a52 ) nb -, where * represents the bonding position with the carbon atom to which -R a50 is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represent -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents any integer from 0 to 4. When mb is any integer of 2 or more, a plurality of R a51 may be the same as or different from each other.]

[0144] R a50 and R a51 Examples of the halogen atom in R R a50 include a fluorine atom, a chlorine atom, a bromine atom, etc. The alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R R a50is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a51 Examples of the alkyl group in a51 include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a51 Examples of the alkoxy group in a51 include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a51 Examples of the alkoxyalkyl group in a51 include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a51 Examples of the alkoxyalkoxy group in a51 include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. R a51 Examples of the alkylcarbonyl group in a51 include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a51Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a51 is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0145] *-X a51 -(A a52 -X a52 ) nb Examples of - include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a52 -CO-O-, *-O-CO-A a52 -O-, *-O-A a52 -CO-O-, *-CO-O-A a52 -O-CO-, *-O-CO-A a52 -O-CO- are included. Among them, *-CO-O-, *-CO-O-A a52 -CO-O- or *-O-A a52 -CO-O- is preferred.

[0146] A a52 Examples of the alkanediyl group in A 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.

[0147] Aa50 is a single bond, *-CO-O- or *-CO-O-A 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.

[0148] mb is preferably 0, 1 or 2, more preferably 0 or 1, and even more preferably 0. The hydroxy group is preferably bonded to the o-position or p-position of the benzene ring, and more preferably bonded to the p-position.

[0149] Examples of the structural unit (a2-A) include structural units derived from the monomers described in JP-A-2010-204634 and JP-A-2012-12577. Examples of the structural unit (a2-A) include the structural units represented by formula (a2-2-1) to formula (a2-2-16) and the structural units in which the methyl group corresponding to R in the structural unit (a2-A) in the structural units represented by formula (a2-2-1) to formula (a2-2-16) is replaced by a hydrogen atom. The structural unit (a2-A) is preferably the structural unit represented by formula (a2-2-1), the structural unit represented by formula (a2-2-3), the structural unit represented by formula (a2-2-6), the structural unit represented by formula (a2-2-8), and the structural units represented by formula (a2-2-12) to formula (a2-2-14), and the structural units in which the methyl group corresponding to R in the structural unit (a2-A) in these structural units is replaced by a hydrogen atom. a50 to the structural units in which the methyl group corresponding to R in the structural unit (a2-A) is replaced by a hydrogen atom. a50 is preferably the structural unit in which the methyl group corresponding to R in the structural unit (a2-A) is replaced by a hydrogen atom. TIFF0007704517000106.tif63169

[0150] When the resin (A) contains the structural unit (a2-A), the content of the structural unit (a2-A) is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, even more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol% based on all the structural units. The structural unit (a2-A) can be incorporated into the resin (A) by, for example, polymerizing using the structural unit (a1-4) and then treating with an acid such as p-toluenesulfonic acid. Also, after polymerizing using acetoxystyrene or the like and then treating with an alkali such as tetramethylammonium hydroxide, the structural unit (a2-A) can be incorporated into the resin (A).

[0151] Examples of the structural unit having an alcoholic hydroxy group in the structural unit (a2) include the structural unit represented by the formula (a2-1) (hereinafter sometimes referred to as "structural unit (a2-1)"). In the formula (a2-1) in TIFF0007704517000107.tif4359 L a3 represents -O- or *-O-(CH2) k2 -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 represent a hydrogen atom, a methyl group or a hydroxy group. o1 represents an integer of any one of 0 to 10.

[0152] In the formula (a2-1), L a3 is preferably -O-, -O-(CH2) f1 -CO-O- (wherein f1 represents an integer of any one of 1 to 4), more preferably -O-. R a14 is preferably a methyl group. R a15 is preferably a hydrogen atom. R a16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of any one of 0 to 3, more preferably 0 or 1.

[0153] Examples of the structural unit (a2-1) include structural units derived from the monomers described in JP-A-2010-204646. The structural unit represented by any of formulas (a2-1-1) to (a2-1-6) is preferred, the structural unit represented by any of formulas (a2-1-1) to (a2-1-4) is more preferred, and the structural unit represented by formula (a2-1-1) or formula (a2-1-3) is even more preferred. TIFF0007704517000108.tif51142

[0154] When the resin (A) contains the structural unit (a2-1), the content thereof is usually 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and even more preferably 1 to 10 mol% based on all the structural units of the resin (A).

[0155] 〈Structural unit (a3)〉 The lactone ring of the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)) can be mentioned.

[0156] The structural unit (a3) is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3), or formula (a3-4). These may be contained alone or in combination of two or more. TIFF0007704517000109.tif52165[In formulas (a3-1), (a3-2), (a3-3) and (a3-4), L a4 、L a5 and L a6 each independently represents a group represented by -O- or *-O-(CH2) k3 -CO-O- (where k3 represents an integer of 1 to 7). L a7 is -O-, *-O-La8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding position with the carbonyl group. R a18 R a19 and R a20 each independently represents a hydrogen atom or a methyl group. R a24 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 R a23 and R a25 each independently represents a carboxy group, a cyano group or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents any integer from 0 to 5. q1 represents any integer from 0 to 3. r1 represents any integer from 0 to 3. w1 represents any integer from 0 to 8. When p1, q1, r1 and / or w1 is 2 or more, the plurality of R a21 R a22 R a23 and / or R a25 may be the same as or different from each other.

[0157] R a21 R a22 R a23 and R a25Examples of the aliphatic hydrocarbon group in [context] include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, and tert-butyl group. R a24 Examples of the halogen atom in [context] include fluorine atom, chlorine atom, bromine atom, and iodine atom. R a24 Examples of the alkyl group in [context] include methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl group, etc. Preferably, alkyl groups having 1 to 4 carbon atoms are included, and more preferably, methyl group or ethyl group is included. R a24 Examples of the alkyl group having a halogen atom in [context] include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group, perfluorohexyl group, trichloromethyl group, tribromomethyl group, triiodomethyl group, etc.

[0158] L a8 and L a9 Examples of the alkanediyl group in [context] and [context] include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group, etc.

[0159] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently, preferably -O- or, *-O-(CH2) k3 -CO-O- where k3 is an integer from 1 to 4, more preferably -O- and, *-O-CH2-CO-O-, and even more preferably an oxygen atom. R a18 ~Ra21 is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group or a methyl group. p1, q1 and r1 are each independently preferably any integer from 0 to 2, more preferably 0 or 1.

[0160] In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, still more preferably a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-O-L a8 -CO-O-, more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. w1 is preferably any integer from 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)'. TIFF0007704517000110.tif4557 (wherein R a24 , L a7 represent the same meanings as described above.)

[0161] Examples of the structural unit (a3) include structural units derived from the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. Examples of the structural unit (a3) include structural units represented by any of formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2), formula (a3-3-1), formula (a3-3-2) and formula (a3-4-1) to formula (a3-4-12), and in the above structural units, R a18 , R a19 , R a20 and Ra24 A structural unit in which the methyl group corresponding thereto is replaced by a hydrogen atom is preferred.

[0162] TIFF0007704517000111.tif117168

[0163] When the resin (A) contains the structural unit (a3), the total content is usually 5 to 70 mol%, preferably 10 to 65 mol%, more preferably 10 to 60 mol% with respect to all the structural units of the resin (A). In addition, the content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3) or the structural unit (a3-4) is preferably 5 to 60 mol%, more preferably 5 to 50 mol%, still more preferably 10 to 50 mol% with respect to all the structural units of the resin (A), respectively.

[0164] 〈Structural unit (a4)〉 Examples of the structural unit (a4) include the following structural units. TIFF0007704517000112.tif3270[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having a halogen atom with 1 to 24 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.] R 42 The saturated hydrocarbon group represented by includes a chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these.

[0165] 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 cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group; polycyclic alicyclic saturated hydrocarbon groups such as decahydronaphthyl group, adamantyl group, norbornyl group and the following group (* represents the bonding site). Examples of the group formed by the combination of include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, such as -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group, and the like.

[0166] Examples of the structural unit (a4) include the structural unit represented by the formula (a4-0), the structural unit represented by the formula (a4-1), and the structural unit represented by the formula (a4-4). TIFF0007704517000114.tif4652[In the formula (a4-0), R 54 represents a hydrogen atom or a methyl group. L 4a represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 3a represents a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms. R 64 represents a hydrogen atom or a fluorine atom.]

[0167] L 4a Examples of the alkanediyl group in 4a include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group and 2-methylpropane-1,2-diyl group.

[0168] L 3aExamples of the perfluoroalkanediyl group include difluoromethylene group, perfluoroethylene group, perfluoroethylfluoromethylene group, perfluoropropane-1,3-diyl group, perfluoropropane-1,2-diyl group, perfluoropropane-2,2-diyl group, perfluorobutane-1,4-diyl group, perfluorobutane-2,2-diyl group, perfluorobutane-1,2-diyl group, perfluoropentane-1,5-diyl group, perfluoropentane-2,2-diyl group, perfluoropentane-3,3-diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1,7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3,3-diyl group, perfluorooctane-4,4-diyl group, and the like. L 3a Examples of the perfluorocycloalkanediyl group include perfluorocyclohexanediyl group, perfluorocyclopentanediyl group, perfluorocycloheptanediyl group, perfluoroadamantanediyl group, and the like.

[0169] L 4a is preferably a single bond, a methylene group or an ethylene group, more preferably a single bond or a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0170] Examples of the structural unit (a4-0) include the structural units shown below and the structural units in the following structural units where the methyl group corresponding to R in the structural unit (a4-0) is replaced by a hydrogen atom. 54 include the structural units in which the methyl group corresponding to R in the structural unit (a4-0) is replaced by a hydrogen atom. TIFF0007704517000115.tif97168

[0171] TIFF0007704517000116.tif4867In formula (a4-1), R a41 represents a hydrogen atom or a methyl group. R a42 represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. A a41 represents an alkanediyl group having 1 to 6 carbon atoms which may have a substituent or a group represented by formula (a-g1). However, at least one of a41 A a42 and R has a halogen atom (preferably a fluorine atom) as a substituent. TIFF0007704517000117.tif1592[In formula (a-g1), s represents 0 or 1. A a42 and A a44 each independently represent a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. A a43 represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a substituent. X a41 and X a42 each independently represent -O-, -CO-, -CO-O- or -O-CO-. However, the total number of carbon atoms of a42 A a43 A a44 X a41 and X a42 is 7 or less.] * represents a bonding site, and the * on the right side is the bonding site with -O-CO-R a42 .

[0172] R a42 Examples of the saturated hydrocarbon group in R include a chain hydrocarbon group, a monocyclic or polycyclic saturated alicyclic hydrocarbon group, and a group formed by combining these.

[0173] Examples of the chained 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, an octadecyl group, and the like. Examples of the monocyclic or polycyclic saturated alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group; polycyclic alicyclic hydrocarbon groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group (* represents a bonding site). Examples of the group formed by the combination of TIFF0007704517000118.tif10159 include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more saturated alicyclic hydrocarbon groups, such as -alkanediyl group-saturated alicyclic hydrocarbon group, -saturated alicyclic hydrocarbon group-alkyl group, -alkanediyl group-saturated alicyclic hydrocarbon group-alkyl group, and the like.

[0174] R a42 Examples of the substituent that R has include at least one selected from the group consisting of a halogen atom and a group represented by the formula (a-g3). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable. TIFF0007704517000119.tif855 [In the formula (a-g3), X a43 represents an oxygen atom, a carbonyl group, *-O-CO- or *-CO-O-. A a45 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. * is the bonding site with R a42 . However, in R a42 -X a43 -A a45 , when R a42 does not have a halogen atom, A a45 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which has at least one halogen atom.

[0175] A a45 Examples of the saturated hydrocarbon group in [compound name] include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl; monocyclic alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl; and polycyclic alicyclic hydrocarbon groups such as decahydronaphthyl, adamantyl, norbornyl, and the following group (* represents the bonding site). Examples of the group formed by the combination of TIFF0007704517000120.tif10159 include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group - alicyclic hydrocarbon group, -alicyclic hydrocarbon group - alkyl group, -alkanediyl group - alicyclic hydrocarbon group - alkyl group, and the like.

[0176] R a42 R is preferably a saturated hydrocarbon group which may have a halogen atom, more preferably an alkyl group having a halogen atom and / or a saturated hydrocarbon group having a group represented by formula (a-g3). R a42 When R 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, still more preferably a perfluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably a perfluoroalkyl group having 1 to 3 carbon atoms. Examples of the perfluoroalkyl group include perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, perfluorohexyl, perfluoroheptyl, and perfluorooctyl. Examples of the perfluorocycloalkyl group include perfluorocyclohexyl. R a42When R is a saturated hydrocarbon group having a group represented by the formula (a-g3), including the number of carbon atoms contained in the group represented by the formula (a-g3), a42 the total number of carbon atoms of R is preferably 15 or less, more preferably 12 or less. When having a group represented by the formula (a-g3) as a substituent, the number thereof is preferably 1.

[0177] R a42 When R is a saturated hydrocarbon group having a group represented by the formula (a-g3), a42 R is more preferably a group represented by the formula (a-g2). TIFF0007704517000121.tif871 [In the 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 the bonding site with A a46 .). A a47 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. However, the total number of carbon atoms of A a46 , A a47 and X a44 is 18 or less, and at least one of A a46 and A a47 has at least one halogen atom. * represents the bonding site with the carbonyl group.]

[0178] A a46 The number of carbon atoms of the saturated hydrocarbon group is preferably 1 to 6, more preferably 1 to 3. A a47 The number of carbon atoms of the saturated hydrocarbon group is preferably 4 to 15, more preferably 5 to 12, and A a47 is more preferably a cyclohexyl group or an adamantyl group.

[0179] A preferred structure of the group represented by the formula (a-g2) is the following structure (* is the bonding site with the carbonyl group). TIFF0007704517000122.tif14160

[0180] A a41 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, 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.

[0181] 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 a linear or branched alkanediyl group, a monocyclic divalent alicyclic saturated hydrocarbon group, and a divalent saturated hydrocarbon group formed by combining an alkanediyl group and a divalent alicyclic saturated hydrocarbon group, etc. Specific examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, 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.

[0182] In the group represented by formula (a-g1), X a42Examples of the group being -O-, -CO-, -CO-O- or -O-CO- include the following groups and the like. In the following examples, * and ** each represent a bonding site, and ** is -O-CO-R a42 is the bonding site with. TIFF0007704517000123.tif46140

[0183] Examples of the structural unit represented by formula (a4-1) include the following structural units and the structural units in the following structural units where the methyl group corresponding to R a41 in formula (a4-1) is replaced by a hydrogen atom. TIFF0007704517000124.tif97142

[0184] TIFF0007704517000125.tif132150

[0185] Examples of the structural unit represented by formula (a4-1) include the structural unit represented by formula (a4-2) and the structural unit represented by formula (a4-3). TIFF0007704517000126.tif4560[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 having a fluorine atom. However, the upper limit of the total carbon number of L 44 and R f6 is 21.]

[0186] L 44 The alkanediyl group having 1 to 6 carbon atoms of may be the same groups as those exemplified by A a41 R f6 The saturated hydrocarbon group of may be the same groups as those exemplified by R 42 L​​44 As the alkanediyl group in 44 , an alkanediyl group having 2 to 4 carbon atoms is preferable, and an ethylene group is more preferable.

[0187] Examples of the structural unit represented by formula (a4-2) include structural units represented by formulas (a4-1-1) to (a4-1-11), respectively. The methyl group corresponding to R in the structural unit (a4-2) f5 The structural unit in which the methyl group is replaced by a hydrogen atom is also included as the structural unit represented by formula (a4-2).

[0188] TIFF0007704517000127.tif5974 [In formula (a4-3), R f7 represents a hydrogen atom or a methyl group. L 5 represents an alkanediyl group having 1 to 6 carbon atoms. A f13 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms which may have a fluorine atom. X f12 represents *-O-CO- or *-CO-O- (* represents the bonding site with A f13 ).). A f14 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, at least one of A f13 and A f14 has a fluorine atom, and the upper limit of the total carbon number of L 5 , A f13 and A f14 is 20.]

[0189] L 5 Examples of the alkanediyl group in 5 include the same groups as those exemplified for the alkanediyl group of A a41 .

[0190] A f13The divalent saturated hydrocarbon group which may have a fluorine atom 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 saturated hydrocarbon group which may have a fluorine atom include alkanediyl groups such as methylene group, ethylene group, propanediyl group, butanediyl group and pentanediyl group; perfluoroalkanediyl groups such as difluoromethylene group, perfluoroethylene group, perfluoropropanediyl group, perfluorobutanediyl group and perfluoropentanediyl group. The divalent alicyclic saturated hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include cyclohexanediyl group and perfluorocyclohexanediyl group. Examples of the polycyclic group include adamantanediyl group, norbornanediyl group, perfluoroadamantanediyl group.

[0191] A f14 The saturated hydrocarbon group and the saturated hydrocarbon group which may have a fluorine atom of a42Groups similar to those exemplified above can be mentioned. Among them, alkyl fluoride groups such as trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, pentyl group, hexyl group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group and perfluorooctyl group; cyclopropylmethyl group, cyclopropyl group, cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantylmethyl group are preferable.

[0192] In formula (a4-3), L 5 is preferably an ethylene group. A f13 The divalent saturated hydrocarbon group of is preferably a group containing a divalent chain saturated hydrocarbon group having 1 to 6 carbon atoms and a divalent alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably a divalent chain saturated hydrocarbon group having 2 to 3 carbon atoms. A f14 The saturated hydrocarbon group of is preferably a group containing a chain saturated hydrocarbon group having 3 to 12 carbon atoms and an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably a group containing a chain saturated hydrocarbon group having 3 to 10 carbon atoms and an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms. Among them, A f14 is preferably a group containing an alicyclic saturated hydrocarbon group having 3 to 12 carbon atoms, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group and an adamantyl group.

[0193] Examples of the structural unit represented by formula (a4-3) include structural units represented by formulas (a4-1'-1) to (a4-1'-11), respectively. In the structural unit (a4-3), the methyl group corresponding to R f7 in which the methyl group is replaced by a hydrogen atom is also included as a structural unit represented by formula (a4-3).

[0194] Examples of the structural unit (a4) also include a structural unit represented by formula (a4-4). TIFF0007704517000128.tif4568[In formula (a4-4), R f21 represents a hydrogen atom or a methyl group. A f21 represents -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -, or -(CH2) j4 -CO-O-(CH2) j5 -. j1 to j5 each independently represent an integer of 1 to 6. R f22 represents a saturated hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom.]

[0195] The saturated hydrocarbon group of R f22 is the same as the saturated hydrocarbon group represented by R a42 . R f22 is preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom or an alicyclic saturated hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0196] In formula (a4-4), A f21 is preferably -(CH2) j1 -, more preferably an ethylene group or a methylene group, and even more preferably a methylene group.

[0197] Examples of the structural unit represented by formula (a4-4) include structural units represented by the following structural units and the following formulas, in which the methyl group corresponding to R in structural unit (a4-4) is replaced by a hydrogen atom. f21 Examples thereof include a structural unit in which the methyl group corresponding to R in structural unit (a4-4) is replaced by a hydrogen atom. TIFF0007704517000129.tif86160

[0198] When the resin (A) has the structural unit (a4), its content is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and even more preferably 3 to 10 mol% based on all the structural units of the resin (A).

[0199] 〈Structural unit (a5)〉 Examples of the non-leaving hydrocarbon group contained in the structural unit (a5) include a group having a linear, branched or cyclic hydrocarbon group. Among them, the structural unit (a5) preferably has a group having an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by formula (a5-1). TIFF0007704517000130.tif3657[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 the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0200] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group. The aliphatic hydrocarbon groups having 1 to 8 carbon atoms include, for example, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. Examples of the alicyclic hydrocarbon group having a substituent include 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group.

[0201] L 55 Examples of the divalent saturated hydrocarbon group in L include divalent chain saturated hydrocarbon groups and divalent alicyclic saturated hydrocarbon groups, and preferably divalent chain saturated hydrocarbon groups. Examples of the divalent chain saturated hydrocarbon group include alkanediyl groups such as methylene group, ethylene group, propanediyl group, butanediyl group and pentanediyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl group and cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl group and norbornanediyl group.

[0202] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO- include the groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom. In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents a bonding site with L x1 .). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the total number of carbon atoms in L x1 and L x2 is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the total number of carbon atoms in L x3 and L x4 is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms in L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, the total number of carbon atoms in L x8 , L x9 and W x1 is 15 or less.

[0203] L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond. L x3is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0204] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF0007704517000132.tif54135

[0205] Examples of the group represented by the formula (L1-2) include the following divalent groups. TIFF0007704517000133.tif23130

[0206] Examples of the group represented by the formula (L1-3) include the following divalent groups. TIFF0007704517000134.tif16145

[0207] Examples of the group represented by formula (L1-4) include, for example, the following divalent groups. TIFF0007704517000135.tif26114

[0208] L 55 is preferably a single bond or a group represented by formula (L1-1).

[0209] Examples of the structural unit (a5-1) include the following structural units and structural units in which the methyl group corresponding to R in the following structural unit (a5-1) is replaced by a hydrogen atom. 51 When the resin (A) has the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and even more preferably 3 to 15 mol% based on all the structural units of the resin (A). TIFF0007704517000136.tif79162

[0210] TIFF0007704517000137.tif40162 When the resin (A) has the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and even more preferably 3 to 15 mol% based on all the structural units of the resin (A).

[0211] <Structural unit (II)> The resin (A) may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (II)"). Specific examples of the structural unit (II) include the structural units described in JP-A-2016-79235, and preferably a structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain or a structural unit having a sulfonio group and an organic anion in the side chain.

[0212] The structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (II-2-A'). TIFF0007704517000138.tif3090 [In formula (II-2-A'), X III3represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, wherein -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -S- or -CO-, and a hydrogen atom contained in the saturated hydrocarbon group may be replaced by a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or a hydroxy group. A x1 represents an alkanediyl group having 1 to 8 carbon atoms, and a hydrogen atom contained in the alkanediyl group may be substituted by a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. RA - represents a sulfonate group or a carboxylate group. R III3 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. ZA + represents an organic cation.

[0213] R III3 Examples of the halogen atom represented by R include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. R III3 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R are the same as those of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R. a8 A x1 Examples of the alkanediyl group having 1 to 8 carbon atoms represented by A include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, a 2-methylbutane-1,4-diyl group and the like. A x1 ​Examples of the C1-C6 perfluoroalkyl group which may be substituted include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluoro sec-butyl group, perfluoro tert-butyl group, perfluoropentyl group, perfluorohexyl group and the like.

[0214] X III3 Examples of the divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by III3 include linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and combinations thereof may also be acceptable. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; divalent monocyclic alicyclic saturated hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group and the like can be mentioned.

[0215] Examples of the group in which -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- include divalent groups represented by formula (X1) to formula (X53). However, the number of carbon atoms before -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- is 17 or less respectively. In the following formulae, * and ** represent bonding sites, and * is A x1represents the binding site with TIFF0007704517000139.tif148164

[0216] 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.

[0217] ZA + Examples of the organic cation represented by ZA include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations are more preferred. Specifically, cations represented by any of the above formulas (b2-1) to (b2-4) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number) can be mentioned.

[0218] The structural unit represented by the formula (II-2-A') is preferably the structural unit represented by the formula (II-2-A). JPEG0007704517000140.jpg37108[In the formula (II-2-A), R III3 、X III3 and ZA + represent the same meaning as above. z represents any integer from 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 z is 2 or more, a plurality of R III2 and R III4 may be the same as or different from each other. Q a and Q b each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms.]

[0219] R III2 、R III4 、Q a and Q b Examples of the perfluoroalkyl group having 1 to 6 carbon atoms represented by b1 are the same as those of the perfluoroalkyl group having 1 to 6 carbon atoms represented by the aforementioned Q

[0220] The structural unit represented by formula (II-2-A) is preferably the structural unit represented by formula (II-2-A-1). TIFF0007704517000141.tif5576[In formula (II-2-A-1), R III2 、R III3 、R III4 、Q a 、Q b 、z and ZA + have the same meanings as described above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, 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 or a hydroxy group.]

[0221] R III5Examples of the saturated hydrocarbon group having 1 to 12 carbon atoms represented by X I2 include the same divalent saturated hydrocarbon groups as those represented by X III3

[0222] As the structural unit represented by the formula (II-2-A-1), the structural unit represented by the formula (II-2-A-2) is preferable. TIFF0007704517000142.tif5288[In the formula (II-2-A-2), R III3 and R III5 and ZA + have the same meanings as described above. m and n each independently represent 1 or 2.]

[0223] Examples of the structural unit represented by the formula (II-2-A') include, for example, the following structural units, and groups corresponding to the methyl group of R III3 are replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group, etc.), and the structural units described in WO 2012 / 050015. ZA + represents an organic cation. TIFF0007704517000143.tif86163

[0224] The structural unit having a sulfonio group and an organic anion in the side chain is preferably the structural unit represented by the formula (II-1-1). TIFF0007704517000144.tif3380[In the formula (II-1-1), A II1 represents a single bond or a divalent linking group. R II1 ​represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R II2 and R II3 each independently represents a hydrocarbon group having 1 to 18 carbon atoms, and R II2 and R II3 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. R II4 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A - represents an organic anion. R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by R R II2 and R II3 Examples of the hydrocarbon group represented by R Examples of the alkyl group and the alicyclic hydrocarbon group are the same as those described above. Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, and phenanthryl group. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group, an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), and an aryl-cycloalkyl group such as phenylcyclohexyl group. R II4 Examples of the halogen atom represented by R R II4 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by R a8Examples thereof include the same alkyl group having 1 to 6 carbon atoms which may have a halogen atom represented by A II1 Examples of the divalent linking group represented by III3 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-. Specifically, X

[0225] Examples of the structural unit containing a cation in formula (II-1-1) include the structural unit represented by the following, R II4 structural units in which a group corresponding to the methyl group of TIFF0007704517000145.tif85130

[0226] A - Examples of the organic anion represented by - include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, carboxylic acid anions, and the like. A

[0227] A - Examples of the sulfonylimide anion represented by TIFF0007704517000146.tif36135

[0228] Examples of the sulfonylmethide anion include the following. TIFF0007704517000147.tif29123

[0229] Examples of the carboxylic acid anion include the following. TIFF0007704517000148.tif51152

[0230] Examples of the structural unit represented by the formula (II-1-1) include the structural units represented below. TIFF0007704517000149.tif88149

[0231] When the resin (A) contains the structural unit (II), the content of the structural unit (II) is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and still more preferably 3 to 10 mol% with respect to all the structural units of the resin (A).

[0232] The resin (A) may have structural units other than the above-described structural units, and examples of such structural units include structural units well-known in the art.

[0233] The resin (A) is preferably a resin composed of the structural unit (a1) and the structural unit (s), that is, a copolymer of the monomer (a1) and the monomer (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group and a cyclopentyl group), more preferably at least two, and still more preferably at least two selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably the structural unit represented by the formula (a2-1) or the structural unit represented by the formula (a2-A). The structural unit (a3) is preferably at least one selected from the group consisting of the structural unit represented by the formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-4).

[0234] Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using the monomers that lead to these structural units. The content of each structural unit of the resin (A) can be adjusted by the amount of the monomers used in the polymerization. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less). In this specification, the weight average molecular weight is the value determined by gel permeation chromatography under the conditions described in the examples.

[0235] <Resin other than resin (A)> The resist composition of the present invention may contain a resin other than the resin (A). Examples of the resin other than the resin (A) include resins containing the structural unit (a4) or the structural unit (a5) (hereinafter sometimes referred to as resin (X)).

[0236] Among them, a resin containing the structural unit (a4) is preferable as the resin (X). In the resin (X), the content of the structural unit (a4) is preferably 30 mol% or more, more preferably 40 mol% or more, still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Examples of the structural unit that the resin (X) may further have include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. Among them, the resin (X) is preferably a resin composed of only the structural unit (a4) and / or the structural unit (a5), and more preferably a resin composed of only 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 (for example, radical polymerization method) using the monomers that lead to these structural units. The content of each structural unit of the resin (X) can be adjusted by the amount of the monomers used in the polymerization. The weight-average molecular weight of resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less). The measuring means for the weight-average molecular weight of resin (X) is the same as that for resin (A). When the resist composition contains resin (X), its content is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, still more preferably 1 to 40 parts by mass, even more preferably 1 to 30 parts by mass, and even still more preferably 1 to 8 parts by mass with respect to 100 parts by mass of resin (A).

[0237] The content rate 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, with respect to the solid content of the resist composition. Also, when the resist composition contains a resin other than resin (A), the total content rate 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, with respect to the solid content of the resist composition. The solid content of the resist composition and the content rate of the resin with respect thereto can be measured by known analysis means such as liquid chromatography or gas chromatography.

[0238] <Solvent (E)> The content rate of 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, more preferably 94% by mass or more and 99% by mass or less. The content rate of solvent (E) can be measured by known analysis means such as liquid chromatography or gas chromatography. Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; and the like. One kind of the solvent (E) may be used alone, or two or more kinds may be used.

[0239] <Quencher (C)> Examples of the quencher (C) include basic nitrogen-containing organic compounds and salts that generate an acid having a lower acidity than the acid generated from the acid generator (B). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15% by mass, more preferably about 0.01 to 10% by mass, still more preferably about 0.01 to 7% by mass, and even more preferably about 0.1 to 3% by mass, based on the solid content of the resist composition. Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. Examples of the amine include aliphatic amines and aromatic amines. Examples of the aliphatic amine include primary amines, secondary amines, and tertiary amines. Examples of the amine include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 1,2-di(4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridylsulfide, 4,4'-dipyridyldisulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine, etc. Of these, diisopropylaniline is preferred, and 2,6-diisopropylaniline is more preferred. 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.

[0240] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is represented by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is a salt having an acid dissociation constant of the acid generated from the salt usually of -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. Preferably, it is a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (B) (a salt having a carboxylic acid anion), and more preferably, it is the weak acid inner salt (D). TIFF0007704517000150.tif90165

[0241] Examples of the weak acid inner salt (D) include the following salts. TIFF0007704517000151.tif72165

[0242] 〈Other Components〉 The resist composition of the present invention may contain, if necessary, components other than the above-described components (hereinafter sometimes referred to as "other components (F)"). There is no particular limitation on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc. can be used.

[0243] 〈Preparation of Resist Composition〉 The resist composition of the present invention can be prepared by mixing salt (I), resin (A) and acid generator (B), and, if necessary, a resin other than resin (A) used, solvent (E), quencher (C) and other components (F). The mixing order is arbitrary and is not particularly limited. The temperature during mixing can be appropriately selected from 10 to 40 °C according to the type of resin, etc. and the solubility of the resin, etc. in solvent (E). The mixing time can be appropriately selected from 0.5 to 24 hours according to the mixing temperature. Note that the mixing means is also not particularly limited, and stirring and mixing, etc. can be used. After mixing each component, it is preferable to filter using a filter with a pore size of about 0.003 to 0.2 μm.

[0244] 〈Method for Manufacturing Resist Pattern〉 The method for manufacturing a resist pattern of the present invention (1) A step of applying the resist composition of the present invention onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer. To apply the resist composition onto a substrate, it can be carried out by 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, or an antireflection film or the like may be formed on the substrate. By drying the composition after coating, the solvent is removed to form a composition layer. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-bake), or by using a decompression device. The heating temperature is preferably 50 to 200 °C, and the heating time is preferably 10 to 180 seconds. Also, the pressure during vacuum drying is preferably about 1 to 1.0×10 5 Pa. The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. As the exposure light source, those that emit laser light in the ultraviolet region such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), those that convert laser light from a solid laser light source (such as YAG or semiconductor laser) to emit harmonic laser light in the far ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams, extreme ultraviolet light (EUV), etc., various ones can be used. In this specification, irradiating these radiations may be collectively referred to as "exposure". During exposure, usually, exposure is performed through a mask corresponding to the required pattern. When the exposure light source is an electron beam, exposure may be performed by direct drawing without using a mask. The composition layer after exposure is heat-treated (so-called post-exposure bake) to promote the deprotection reaction in the acid-labile group. The heating temperature is usually about 50 to 200 °C, preferably about 70 to 150 °C. The composition layer after heating is usually developed using a developing solution with a developing device. Examples of the developing method include dip method, paddle method, spray method, dynamic dispense method, etc. The developing temperature is preferably, for example, 5 to 60 °C, and the developing time is preferably, for example, 5 to 300 seconds. By selecting the type of developing solution as follows, a positive resist pattern or a negative resist pattern can be manufactured. When producing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. For example, aqueous solutions of tetramethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline), etc. can be mentioned. The alkaline developer may contain a surfactant. After development, it is preferable to wash the resist pattern with ultrapure water and then remove the water remaining on the substrate and the pattern. When producing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic developer") is used as the developer. Examples of the organic solvent contained in the organic developer include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole, etc. In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and even more preferably substantially only the organic solvent. Among them, as the organic developer, a developer containing butyl acetate and / or 2-heptanone is preferable. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant. Also, the organic developer may contain a small amount of water. During development, the development may be stopped by substituting with a solvent of a different type from the organic developer. It is preferable to wash the developed resist pattern with a rinse solution. The rinse solution is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After washing, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

[0245] <Usage> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, an ArF excimer laser exposure resist composition, an electron beam (EB) exposure resist composition, or an EUV exposure resist composition, particularly as an electron beam (EB) exposure resist composition or an EUV exposure resist composition, and is useful for semiconductor microfabrication.

Examples

[0246] The present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing the content or the amount used are based on mass unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography. The analysis conditions for gel permeation chromatography are as follows. Column: TSKgel Multipore HXL-M x 3 + guard column (manufactured by Tosoh Corporation) Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 °C Injection volume: 100 μl Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation) The structure of the compound was confirmed by measuring the molecular ion peak using mass spectrometry (LC is Agilent 1100 type, MASS is Agilent LC / MSD type). In the following examples, the value of this molecular ion peak is indicated by “MASS”.

[0247] Example 1: Synthesis of the salt represented by formula (I-5) 10 parts of the salt represented by TIFF0007704517000152 (I-5-a) and 100 parts of acetonitrile were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 7.01 parts of the compound represented by the formula (I-5-b) was added, and after stirring at 60 °C for 2 hours, 25.55 parts of the compound represented by the formula (I-5-c) was added, and after stirring at 60 °C for 2 hours, it was cooled to 23 °C. To the resulting reaction mixture, 150 parts of chloroform and 50 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the recovered organic layer, 50 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, 50 parts of tert-butyl methyl ether was added to the resulting residue, and after stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 22.68 parts of the salt represented by the formula (I-5).

[0248] MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 1389.6

[0249] Example 2: Synthesis of the salt represented by the formula (I-6) 10 parts of the salt represented by TIFF0007704517000153 (I-5-a) and 100 parts of acetonitrile were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 7.01 parts of the compound represented by the formula (I-5-b) was added, and after stirring at 60 °C for 2 hours, 31.35 parts of the compound represented by the formula (I-6-c) was added, and after stirring at 60 °C for 2 hours, it was cooled to 23 °C. To the resulting reaction mixture, 150 parts of chloroform and 50 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the recovered organic layer, 50 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, 50 parts of tert-butyl methyl ether was added to the resulting residue, and after stirring at 23 °C for 30 minutes, it was filtered to obtain 31.69 parts of the salt represented by the formula (I-6).

[0250] MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 1657.7

[0251] Example 3: Synthesis of the salt represented by formula (I-1) 10 parts of the salt represented by formula (I-5-a) and 100 parts of acetonitrile were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 7.01 parts of the compound represented by formula (I-5-b) was added, and after stirring at 60 °C for 2 hours, 23.64 parts of the compound represented by formula (I-1-c) was added. After stirring at 60 °C for 2 hours, the mixture was cooled to 23 °C. To the resulting reaction mixture, 150 parts of chloroform and 50 parts of ion-exchanged water were added, and the mixture was stirred at 23 °C for 30 minutes, followed by liquid separation to obtain the organic layer. To the recovered organic layer, 50 parts of ion-exchanged water was added, and the mixture was stirred at 23 °C for 30 minutes, followed by liquid separation to obtain the organic layer. This washing operation was repeated 5 times. The obtained organic layer was concentrated, and to the resulting residue, 50 parts of tert-butyl methyl ether was added and stirred at 23 °C for 30 minutes. The supernatant was removed and concentrated to obtain 24.16 parts of the salt represented by formula (I-1).

[0252] MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 1301.5

[0253] Example 4: Synthesis of the salt represented by formula (I-15) 10 parts of the salt represented by TIFF0007704517000155.tif109156 formula (I-5-a) and 100 parts of acetonitrile were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 7.01 parts of the compound represented by formula (I-5-b) were added, and after stirring at 60 °C for 2 hours, 19.14 parts of the compound represented by formula (I-15-c) were added, and after stirring at 60 °C for 2 hours, it was cooled to 23 °C. To the resulting reaction mixture, 150 parts of chloroform and 50 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the recovered organic layer, 50 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, 50 parts of tert-butyl methyl ether were added to the obtained residue, and after stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 20.22 parts of the salt represented by formula (I-15).

[0254] MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 1093.4

[0255] Example 5: Synthesis of the salt represented by formula (I-16) 9.13 parts of the salt represented by TIFF0007704517000156.tif81149 formula (I-16-a) and 100 parts of acetonitrile were mixed and stirred at 23 °C for 30 minutes. To the obtained mixed solution, 3.51 parts of the compound represented by formula (I-5-b) was added, and after stirring at 60 °C for 2 hours, 9.57 parts of the compound represented by formula (I-15-c) was added, and after stirring at 60 °C for 2 hours, it was cooled to 23 °C. To the obtained reaction mixture, 150 parts of chloroform and 50 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the recovered organic layer, 50 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This water washing operation was repeated 5 times. The obtained organic layer was concentrated, 50 parts of tert-butyl methyl ether was added to the obtained residue, and after stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 12.19 parts of the salt represented by formula (I-16).

[0256] MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 625.2

[0257] Example 6: Synthesis of the salt represented by formula (I-129) 10 parts of the salt represented by TIFF0007704517000157 (I-5-a) and 100 parts of acetonitrile were mixed and stirred at 23 °C for 30 minutes. To the resulting mixed solution, 7.01 parts of the compound represented by the formula (I-5-b) was added, and after stirring at 60 °C for 2 hours, 31.68 parts of the compound represented by the formula (I-129-c) was added, and after stirring at 60 °C for 2 hours, it was cooled to 23 °C. To the resulting reaction mixture, 150 parts of chloroform and 50 parts of ion-exchanged water were added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. To the recovered organic layer, 50 parts of ion-exchanged water was added, and after stirring at 23 °C for 30 minutes, the layers were separated and the organic layer was taken out. This washing operation was repeated 5 times. The resulting organic layer was concentrated, and to the resulting residue, 50 parts of tert-butyl methyl ether was added, and after stirring at 23 °C for 30 minutes, the supernatant was removed and concentrated to obtain 32.92 parts of the salt represented by the formula (I-129).

[0258] MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 1673.5

[0259] Synthesis of Resin 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. TIFF0007704517000158.tif3897

[0260] Synthesis Example 1 [Synthesis of Resin A1] As monomers, monomer (a1-4-2), monomer (a1-1-3) and monomer (a1-2-6) were used and mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-1-3): monomer (a1-2-6)] was 38:24:38. Further, methyl isobutyl ketone in an amount 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator in an amount of 7 mol% respectively based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was performed. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and the weight average molecular weight was about 5.3×10 3 Resin A1 (copolymer) with this was obtained at a yield of 78%. This resin A1 has the following structural units. TIFF0007704517000159.tif29127

[0261] Synthesis Example 2 [Synthesis of Resin A2] As monomers, monomer (a1-4-2) and monomer (a1-2-6) were used and mixed so that the molar ratio [monomer (a1-4-2): monomer (a1-2-6)] was 38:62. Further, methyl isobutyl ketone in an amount 1.5 times the total mass of all monomers was mixed into this monomer mixture. To the resulting mixture, azobisisobutyronitrile was added as an initiator in an amount of 7 mol% respectively based on the total number of moles of all monomers, and polymerization was carried out by heating this at 85 °C for about 5 hours. Thereafter, an aqueous solution of p-toluenesulfonic acid was added to the polymerization reaction solution, and after stirring for 6 hours, liquid separation was performed. The obtained organic layer was poured into a large amount of n-heptane to precipitate the resin, and the resin was obtained by filtration and recovery, and the weight average molecular weight was about 5.7×10 3 Resin A2 (copolymer) with this was obtained at a yield of 86%. This resin A2 has the following structural units. TIFF0007704517000160.tif2692

[0262] <Preparation of Resist Composition> As shown in Table 2, each of the following components was mixed, and the resulting mixture was filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a resist composition.

Table 2

[0263] <Resin> A1, A2, Resin A1, Resin A2 <Salt (I)> I-1: Salt represented by formula (I-1) I-5: Salt represented by formula (I-5) I-6: Salt represented by formula (I-6) I-15: Salt represented by formula (I-15) I-16: Salt represented by formula (I-16) I-129: Salt represented by formula (I-129) <Acid Generator (B)> IX-1: Salt represented by formula (IX-1); synthesized by the method described in JP-A-2005-097254 TIFF0007704517000162.tif3755IX-2: Salt represented by formula (IX-2); synthesized by the method described in JP-A-2005-097254 TIFF0007704517000163.tif2958IX-3: Salt represented by formula (IX-3); synthesized by the method described in JP-A-2004-203858 TIFF0007704517000164.tif3858IX-4: Salt represented by formula (IX-4); synthesized with reference to the method described in JP-A-2017-088865 TIFF0007704517000165.tif3867<Quencher (C)> C1-1: Synthesized by the method described in JP-A-2011-39502 TIFF0007704517000166.tif3646<Solvent (E)> Propylene Glycol Monomethyl Ether Acetate 300 parts 300 parts of propylene glycol monomethyl ether 5 parts of γ-butyrolactone

[0264] (Electron beam exposure evaluation of resist composition) A 6-inch silicon wafer was treated on a direct hot plate with hexamethyldisilazane at 90 °C for 60 seconds. The resist composition was spin-coated on this silicon wafer so that the film thickness of the composition layer was 0.04 μm. Then, it was pre-baked on a direct hot plate at the temperature shown in the "PB" column of Table 2 for 60 seconds to form a composition layer. A line-and-space pattern (pitch 60 nm / line width 30 nm) was directly drawn on the composition layer formed on the wafer using an electron beam lithography machine ["ELS-F125 125 keV" manufactured by Elionix, Inc.] while changing the exposure dose stepwise. After exposure, post-exposure baking was performed on a hot plate at the temperature shown in the "PEB" column of Table 2 for 60 seconds, and further paddle development was performed with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide for 60 seconds to obtain a resist pattern. The obtained resist pattern (line-and-space pattern) was observed with a scanning electron microscope, and the exposure dose at which the line width and space width of the line-and-space pattern with a pitch of 60 nm became 1:1 was defined as the effective sensitivity. Line edge roughness evaluation (LER): The amplitude of the unevenness of the side wall surface of the resist pattern manufactured with the effective sensitivity was measured with a scanning electron microscope to obtain the line edge roughness. The results are shown in Table 3.

Table 3

Industrial Applicability

[0265] The salt of the present invention and the resist composition containing the same are suitable for semiconductor microfabrication and extremely useful industrially because a resist pattern having good line edge roughness (LER) can be obtained.

Claims

1. A salt represented by formula (I). [In formula (I), L １’ represents a trivalent group represented by the formula (L １ -1X'). (In formula (L １ -1X'), X ０Ｘ’ represents a divalent aliphatic hydrocarbon group having 2 to 48 carbon atoms, and -CH 2 - contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-. However, in X ０Ｘ’ , among the -CH 2 - contained in the aliphatic hydrocarbon group, -CH 2 - bonded to the benzene ring to which the sulfonate anion is bonded is replaced by -CO-, and further, the adjacent -CH2- is replaced by -O-. X １Ｘ and X ２Ｘ each independently represents a divalent aliphatic hydrocarbon group having 1 to 48 carbon atoms, and -CH 2 - in the aliphatic hydrocarbon group may be replaced by -O- or -CO-. However, in each of X １Ｘ and X ２Ｘ , at least one of -CH 2 - in the aliphatic hydrocarbon group is replaced by -O- or -CO-. *0 represents a bond to a carbon atom of the benzene ring. *1 represents a bond with R １ and is represented by a bond with R *2 represents a bond with R ２ ​ R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms.) R １ and R ２ each independently represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ - n represents an integer of any one of 1 to 3. When n is 2 or 3, a plurality of L １ , a plurality of R １ and a plurality of R ２ may be the same or different. Z ＋ represents an organic cation.]

2. A salt represented by formula (I'). [In formula (I'), L １ represents a trivalent group represented by the formula (L １ -1X). (In formula (L １ -1X), X ０Ｘ , X １Ｘ and X ２Ｘ each independently represents a divalent aliphatic hydrocarbon group having 1 to 48 carbon atoms, and -CH 2 - contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-. However, in each of X ０Ｘ , X １Ｘ and X ２Ｘ , at least one of -CH 2 - contained in the aliphatic hydrocarbon group is replaced by -O- or -CO-. *0 represents a bond to a carbon atom of the benzene ring. *1 represents a bond with R １ and is shown as a bond. *2 represents a bond with R ２ ​ R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms.) R １ and R ２ each independently represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ - n' represents 2 or 3, and a plurality of L １ , a plurality of R １ and a plurality of R ２ may be the same or different. Z ＋ represents an organic cation.

3. A salt represented by formula (I''). [In formula (I''), L １ represents a trivalent group represented by the formula (L １ -1X). (In formula (L １ -1X), X ０Ｘ , X １Ｘ and X ２Ｘ each independently represents a divalent aliphatic hydrocarbon group having 1 to 48 carbon atoms, and the -CH 2 - contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-. However, in each of X ０Ｘ , X １Ｘ and X ２Ｘ , at least one of the -CH 2 - contained in the aliphatic hydrocarbon group is replaced by -O- or -CO-. *0 represents a bond to a carbon atom of the benzene ring. *1 represents a bond with R １’ and. *2 represents a bond with R ２’ ​ R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms.) R １’ and R ２’ each independently represents a saturated hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH 2 - in the saturated hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ -. n represents an integer of any one of 1 to 3. When n is 2 or 3, a plurality of L １ , a plurality of R １’ and a plurality of R ２’ may be the same or different. Z ＋ represents an organic cation.]

4. A salt represented by formula (I'''). [In formula (I'''), L １’’ represents a trivalent group represented by the formula (L １ -1X''). (In formula (L １ -1X''), X ０Ｘ , X １Ｘ and X ２Ｘ each independently represents a divalent aliphatic hydrocarbon group having 1 to 48 carbon atoms, and the -CH 2 - contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-. However, in each of X ０Ｘ , X １Ｘ and X ２Ｘ , at least one of the -CH 2 - contained in the aliphatic hydrocarbon group is replaced by -O- or -CO-. *0 represents a bond to a carbon atom of the benzene ring. *1 represents a bond with R １’’ ​ *2 represents a bond with R ２’’ and is shown as a bond to R R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms.) R １’’ and R ２’’ each represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ -. However, -X １Ｘ -R １’’ and -X ２Ｘ -R ２’’ are the same group. n represents an integer of any one of 1 to 3. When n is 2 or 3, a plurality of L １’’ , a plurality of R １’’ and a plurality of R ２’’ may be the same or different from each other, respectively. Z ＋ represents an organic cation.]

5. L １ is a trivalent group represented by formula (L １ -1), formula (L １ -2) or formula (L １ -3): the salt according to claim 2 or 3. [Formula (L １ -1), Formula (L １ -2) and Formula (L １ -3), among them, X ０ represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 14 carbon atoms, or a group represented by the formula (a-1). (In formula (a-1), s represents 0 or 1. X 10 and X 1１ each independently represents -O-**, -CO-**, -CO-O-** or -O-CO-**. ** represents A 1１ or A 1２ and represents a bond to A 10 and A 1１ each independently represents a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. A 12 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. * represents a bond with the carbon atom to which R is attached. Ｌ )) X １ represents -O-*1, -O-CO-*1, -O-CH ２ -*1 or -O-CH ２ -CO-O-*1. *1 represents a bond with R １ . X ２ represents -O-*2, -O-CO-*2, -O-CH ２ -*2 or -O-CH ２ -CO-O-*2. *2 represents a bond with R ２ . X ３ represents -O-*1 or -O-CH ２ -CO-O-*1. *1 represents a bond with R １ ​ X ４ represents -O-*2 or -O-CH ２ -CO-O-*2. *2 represents a bond with R ２ ​ X ５ represents -O-*1, -O-CO-*1 or -O-CH ２ -*1. *1 represents a bond with R １ ​ X ６ represents -O-*2, -O-CO-*2 or -O-CH ２ -*2. *2 represents a bond with R ２ . *0 represents a bond to a carbon atom of the benzene ring. m1, m2, m3, m4 and m5 each independently represent an integer of any one of 0 to 6. R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms.]

6. L １’ is a trivalent group represented by formula (L １ -1) or formula (L １ -2), the salt according to claim 1. [Formula (L １ -1) or formula (L １ -2), X ０ represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 14 carbon atoms, or a group represented by the formula (a-1). (In formula (a-1), s represents 0 or 1. X 10 and X 1１ each independently represents -O-**, -CO-**, -CO-O-** or -O-CO-**. ** represents A 1１ or A 1２ and represents a bond to A 10 and A 1１ each independently represents a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. A 12 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. * represents a bond with the carbon atom to which R is attached.) Ｌ (Here, * represents a bond with the carbon atom to which R is attached.) X １ represents -O-*1, -O-CO-*1, -O-CH ２ -*1 or -O-CH ２ -CO-O-*1. *1 represents a bond with R １ . X ２ represents -O-*2, -O-CO-*2, -O-CH ２ -*2 or -O-CH ２ -CO-O-*2. *2 represents a bond with R ２ . X ３ represents -O-*1 or -O-CH ２ -CO-O-*1. *1 represents a bond with R １ . X ４ represents -O-*2 or -O-CH ２ -CO-O-*2. *2 represents a bond with R ２ . *0 represents a bond to a carbon atom of the benzene ring. m1, m2 and m3 each independently represent an integer of any one of 0 to 6. R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms.

7. L １’’ is a trivalent group represented by formula (L １ -1'), formula (L １ -2') or formula (L １ -3'), the salt according to claim 4. [Formula (L １ -1'), Formula (L １ -2') and Formula (L １ -3'), among them, X ０ represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 14 carbon atoms, or a group represented by the formula (a-1). (In formula (a-1), s represents 0 or 1. X 10 and X 1１ each independently represents -O-**, -CO-**, -CO-O-** or -O-CO-**. ** represents A 1１ or A 1２ and represents a bond with A 10 and A 1１ each independently represents a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. A 12 represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms. * represents a bond to the carbon atom to which R is attached.) Ｌ is attached.) X １ represents -O-*1, -O-CO-*1, -O-CH ２ -*1 or -O-CH ２ -CO-O-*1. *1 represents a bond with R １ . X ２ represents -O-*2, -O-CO-*2, -O-CH ２ -*2 or -O-CH ２ -CO-O-*2. *2 represents a bond with R ２ and. X ３ represents -O-*1 or -O-CH ２ -CO-O-*1. *1 represents a bond with R １ . X ４ represents -O-*2 or -O-CH ２ -CO-O-*2. *2 represents a bond with R ２ . X ５ represents -O-*1, -O-CO-*1 or -O-CH ２ -*1. *1 represents a bond with R １ . X ６ represents -O-*2, -O-CO-*2 or -O-CH ２ -*2. *2 represents a bond with R ２ . *0 represents a bond to a carbon atom of the benzene ring. m1, m2, m4 and m5 each independently represent an integer of any one of 0 to 6, m1 and m2 represent the same number, and m4 and m5 represent the same number. m3' represents 0. R Ｌ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 14 carbon atoms. However, X ０ from the binding site *1 and X ０ from the binding site *2 represent the same group. ]

8. The salt according to any one of Claims 1, 3, 4 or Claims 5 to 7 which refer to Claims 1, 3, 4, wherein n is 1 or 2.

9. R １ 、 R １ ’, R １’’ 、 R ２ 、 R ２’ and R ２’’ is an alicyclic hydrocarbon group having 3 to 20 carbon atoms which has a group represented by the formula (1R) or a fluorine atom (however, the -CH 2 - contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ -.). The salt according to any one of claims 1 to 8. [In formula (1R), ring W represents a non-aromatic hydrocarbon ring having 3 to 20 carbon atoms. R represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a group combining these. * represents a bonding site.]

10. An acid generator containing the salt according to any one of Claims 1 to 9.

11. A resist composition containing the acid generator according to Claim 10.

12. The resist composition according to Claim 11, further containing a resin containing a structural unit having an acid-labile group.

13. The resist composition according to Claim 12, wherein the structural unit having an acid-labile group contains at least one selected from the group consisting of a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2). [In formula (a1-1) and formula (a1-2), L ａ１ and L ａ２ each independently represents -O- or *-O-(CH ２ ) ｋ１ -CO-O-, k1 represents any integer from 1 to 7, and * represents the bonding site with -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 alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these. m1 represents an integer of any one of 0 to 14. n1 represents an integer of any one of 0 to 10. n1' represents an integer of any one of 0 to 3.]

14. The resist composition according to claim 12 or 13, wherein the resin containing a structural unit having an acid-labile group contains a structural unit represented by formula (a2-A). [In formula (a2-A), R a50 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a50 represents a single bond or *-X a51 -(A a52 -X a52 ) nｂ -, where * represents the bonding site with the carbon atom to which -R a50 is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is any integer of 2 or more, the plurality of Rs a51 may be the same as or different from each other.]

15. The resist composition according to any one of claims 11 to 14, further containing a salt that generates an acid having a lower acidity than the acid generated from the acid generator.

16. (1) A step of applying the resist composition according to any one of claims 11 to 15 onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, A method for manufacturing a resist pattern including these steps.

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