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

Abstract

To provide a salt, a resist composition, and the like which allow a resist pattern having good line edge roughness to be produced.SOLUTION: The salt is represented by formula (I) [where Q1 and Q2 each represent a fluorine atom or a perfluoroalkyl group; R1 and R2 each represent a hydrogen atom, a fluorine atom or the like; z represents an integer of 0-6; X1 represents *-CO-O-, *-O-CO- or the like; L1 represents a group formed by combining an alkanediyl group and an alicyclic saturated hydrocarbon group; A1 represents a divalent alicyclic hydrocarbon group which may have a halogen atom, a hydroxy group or the like; Ra represents a perfluoroalkyl group; Z+ represents a cation represented by formula (b2-1) or the like; and Rb4-Rb6 each represent a chain hydrocarbon group, an alicyclic hydrocarbon group or an aromatic hydrocarbon group].SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a salt for an acid generator used in semiconductor microfabrication, an acid generator containing the salt, and a resist. The present invention relates to a resist composition and a method for producing a resist pattern. [Background technology]

[0002] Patent Document 1 describes a salt represented by the following formula and a resist composition containing the salt as an acid generator: Things are listed. TIFF0007672459000001.tif2747 Patent Document 2 describes a salt represented by the following formula and a resist composition containing the salt as an acid generator: Things are listed. TIFF0007672459000002.tif2958 [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-161707 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-121937 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention provides a resist pattern formed from a resist composition containing the above salt. The present invention aims to provide a salt that forms a resist pattern with good CD uniformity (CDU). do. [Means for solving the problem]

[0005] The present invention includes the following inventions. [1] A salt represented by formula (I). JPEG0007672459000003.jpg18115 [In formula (I), Q 1 and Q 2 are each independently a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. Represents a group. R 1 and R 2 are each independently a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 6 carbon atoms. represents an alkyl group. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R 1 and R 2 are mutually They may be the same or different. X 1 is *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (however, * indicates C(R 1 )(R 2 ) or C(Q 1 )(Q 2 ) represents the bonding position with ). L 1 represents a single bond or a saturated hydrocarbon group having 1 to 28 carbon atoms, and -CH2- may be replaced by -O-, -S-, -SO2- or -CO-. . A 1 represents a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-. It may have been replaced. R a represents a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms. Z + represents an organic cation.] [2]X 1 *-CO-O- or *-O-CO- (where * is C(R 1 )(R 2 )also is C(Q 1 )(Q 2) represents the bonding position with ). [3]L 1 is a single bond, an alkanediyl group having 1 to 12 carbon atoms (provided that the alkanediyl The —CH2— contained in the group may be replaced with —O— or —CO—. A combination of an alkanediyl group having 1 to 6 carbon atoms and an alicyclic saturated hydrocarbon group having 3 to 18 carbon atoms. and a group formed by combining the group (provided that the -CH2- contained in the alkanediyl group is - The —CH contained in the alicyclic saturated hydrocarbon group may be replaced by —O— or —CO—. 2- may be replaced by -O-, -S-, -SO2- or -CO-. The salt according to [1] or [2]. [4]R a is a perfluoroalkyl group having 1 to 6 carbon atoms or a fluorine atom [1] [3] The salt according to any one of [3]. [5] An acid generator containing the salt according to any one of [1] to [4]. [6] A resist composition comprising the acid generator according to [5] and a resin having an acid labile group. [7] The structural unit having an acid labile group is a structural unit represented by formula (a1-1) and a structural unit represented by formula (a The resist composition according to [6], which contains at least two types of structural units represented by 1-2). TIFF0007672459000004.tif3984 [In formula (a1-1) and formula (a1-2), L a1 and L a2 are each independently -O- or -O-(CH2) k1 -CO-O- In this case, k1 represents an integer of 1 to 7, and * represents a bond to —CO—. R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic group having 3 to 18 carbon atoms, represents a hydrocarbon group of the formula: m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. [8] The resin having an acid labile group further contains a structural unit represented by formula (a2-A): The resist composition according to [6] or [7]. TIFF0007672459000005.tif3844[In formula (a2-A), R a50 is a hydrogen atom, a halogen atom, or a group having 1 to 6 carbon atoms which may have a halogen atom represents an alkyl group represented by the formula: R a51 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a Alkoxy group, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms represents an acryloyloxy group, an acryloyloxy group, or a methacryloyloxy group. A a50 is a single bond or * -X a51 -(A a52 -X a52 ) nb - represents -R a50 is combined represents the bonding site with the carbon atom. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, multiple R in Numbers a51 may be the same or different from each other.] [9] The composition further contains a salt that generates an acid that is weaker in acidity than the acid generated from the acid generator. The resist composition according to any one of items [6] to [8].

[10] Furthermore, the present invention is directed to a method for manufacturing a polymeric material according to any one of [6] to [9], which further contains a resin containing a structural unit having a fluorine atom. The resist composition according to any one of the preceding claims.

[11] (1) A method for coating a resist composition according to any one of [6] to

[10] on a substrate. a process of (2) drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising: [Effects of the Invention]

[0006] By using a resist composition using the salt of the present invention, good CD uniformity (CDU) can be achieved. ) can produce a resist pattern. DETAILED DESCRIPTION OF THE INVENTION

[0007] In this specification, the term "(meth)acrylic monomer" refers to a monomer having a structure such as "CH2=CH-CO-" Monomers having the structure "CH2=C(CH3)-CO-" and monomers having the structure "CH2=C(CH3)-CO-" Similarly, "(meth)acrylate" and "(Meth)acrylic acid" refers to "a group consisting of acrylate and methacrylate" "At least one selected from the group consisting of acrylic acid and methacrylic acid" and "at least one selected from the group consisting of acrylic acid and methacrylic acid "at least one of" "CH2=C(CH3)-CO-" or "CH2=CH-C When a structural unit having "O-" is exemplified, structural units having both groups are also exemplified. In addition, in the groups described in this specification, a linear structure and a branched structure are For those which can have both structures, either one is acceptable. It means a group formed by combining two or more of the groups shown above with their valences appropriately changed. When present, all stereoisomers are included. In this specification, the term "solid content of the resist composition" refers to the amount of the solid content of the resist composition that is the remaining amount of the resist composition. This refers to the total of all components excluding the solvent (E) described below.

[0008] <Salt represented by formula (I)> The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)"). In salt (I), the side with a negative charge is called an anion (I), and the side with a positive charge is called a cationic It is sometimes called "On(I)".

[0009] In formula (I), Q 1 , Q 2 , R 1 and R 2 The perfluoroalkyl group is Trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group perfluoropropyl group, perfluorobutyl group, perfluorosec-butyl group, perfluorot Examples include an ert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. . Q 1 and Q 2 are each independently preferably a trifluoromethyl group or a fluorine atom. and more preferably a fluorine atom. R 1 and R 2 are each independently preferably a hydrogen atom or a fluorine atom. Preferably, z is 0. X 1 *-CO-O- or *-O-CO-(* is C(R 1 )(R 2 ) or C(Q1 ) (Q 2 ) is preferably a bond to the alkyl group.

[0010] L 1 The divalent saturated hydrocarbon group represented by the formula (I) is an alkanediyl group, a monocyclic or polycyclic and alicyclic saturated hydrocarbon groups formed by combining two or more of these groups. It may also be a divalent hydrocarbon group formed from a cyclic hydrocarbon group and an alkanediyl group. Specifically, 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- linear alkanediyl groups such as diyl groups; Ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group 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 branched alkanediyl groups such as 2-methylbutane-1,4-diyl groups; Cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexa cycloalkanediyl groups such as cyclohexene-1,4-diyl and cyclooctane-1,5-diyl a monocyclic divalent alicyclic saturated hydrocarbon group; Norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane- Polycyclic divalent alicyclic saturated carbons such as 1,5-diyl and adamantane-2,6-diyl groups Examples include a hydrogen group. L 1 -CH2- contained in the divalent saturated hydrocarbon group having 1 to 28 carbon atoms is -O-, -S It may be replaced by -, -SO2- or -CO-. L 1 The —CH2— contained in the divalent saturated hydrocarbon group having 1 to 28 carbon atoms represented by the formula: , -S-, -SO2- or -CO-, the number of carbon atoms before substitution is The number of carbon atoms in the hydrocarbon group. L 1 The -CH2- in the alkanediyl group is replaced with -O- or -CO- The group may be a hydroxy group, an alkoxy group, an alkylcarbonyl group, or an alkylcarbonyl group. Examples include an oxy group and a carboxy group, and among these, a hydroxy group is preferred. L 1 is a saturated hydrocarbon group having 1 to 28 carbon atoms (-CH2- contained in the saturated hydrocarbon group is , -O-, -S-, -SO2- or -CO-. However, a single bond, an alkanediyl group having 1 to 12 carbon atoms (provided that the alkanediyl group -CH2- may be replaced by -O- or -CO-) or a group having 1 to 6 carbon atoms A group formed by combining an alkanediyl group and an alicyclic saturated hydrocarbon group having 3 to 18 carbon atoms (but However, -CH2- contained in the alkanediyl group is replaced with -O- or -CO-. The -CH2- contained in the alicyclic saturated hydrocarbon group may be -O-, -S-, -SO2 - or -CO-), or an alkanedi group having 1 to 12 carbon atoms. alkanediyl group (provided that -CH2- contained in the alkanediyl group is replaced with -O- or -CO-) or an alkanediyl group having 1 to 6 carbon atoms and an alicyclic group having 3 to 18 carbon atoms. A group formed by combining a saturated hydrocarbon group (provided that the -CH2 contained in the alkanediyl group - may be replaced by -O- or -CO-, and the alicyclic saturated hydrocarbon group -CH2- may be replaced by -O-, -S-, -SO2- or -CO-. ), and is preferably a single bond, an alkanediyl group having 1 to 12 carbon atoms, or an alkanediyl group having 1 to 6 carbon atoms. and an alicyclic saturated hydrocarbon group having 3 to 18 carbon atoms ( However, -CH2- contained in the alkanediyl group is replaced with -O- or -CO-. It is more preferable that the alkyl group is a single bond or an alkanediyl group having 1 to 12 carbon atoms. or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms with an adamantanediyl group ( However, -CH2- contained in the alkanediyl group is replaced with -O- or -CO-. It is more preferable that the above formula (I) is used.

[0011] A 1 The divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms is a monocyclic or polycyclic divalent Alicyclic hydrocarbon groups are included. Examples of the monocyclic divalent alicyclic hydrocarbon group include a cyclobutane-1,3-diyl group, ... Pentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1 , 5-diyl groups and other cycloalkanediyl groups. Examples of polycyclic divalent alicyclic hydrocarbon groups include norbornane-1,4-diyl group, norbornane-1,4-diyl group, Adamantane-2,5-diyl group, Adamantane-2,2-diyl group, Adamantane-1,5- Examples thereof include a diyl group and an adamantane-2,6-diyl group. A 1The substituents that the alicyclic hydrocarbon group may have include a halogen atom, a hydroxy group, , cyano group, carboxy group, alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms groups and groups in which two or more of these groups are combined. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. do. Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, a propyl group, and an isopropyl group. butyl, isobutyl, tert-butyl, pentyl, hexyl, octyl Examples thereof include a methyl group and a nonyl group. Examples of the alkoxy group having 1 to 12 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a bromine group, and a methyl group. hexyloxy, pentyloxy, hexyloxy, octyloxy, 2-ethylhexyl hydroxyl group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group etc. Examples of the group combining two or more of these include an alkoxycarbonyl group having 2 to 13 carbon atoms, a carbon alkylcarbonyl groups having 2 to 13 carbon atoms and alkylcarbonyloxy groups having 2 to 13 carbon atoms, etc. Examples include: Alkoxycarbonyl groups having 2 to 13 carbon atoms, alkylcarbonyl groups having 2 to 13 carbon atoms, and and alkylcarbonyloxy groups having 2 to 13 carbon atoms are the same as the above-mentioned alkyl or alkoxy groups. It represents a group in which a carbonyl group or a carbonyloxy group is bonded to a silyl group. Examples of the alkoxycarbonyl group having 2 to 13 carbon atoms include a methoxycarbonyl group, an ethoxy group, and carbonyl group, butoxycarbonyl group, etc., and alkylcarbonyl groups having 2 to 13 carbon atoms. Examples of the alkyl group include an acetyl group, a propionyl group, and a butyryl group, and the alkyl group has 2 to 1 carbon atoms. The alkylcarbonyloxy group of 3 includes an acetyloxy group, a propionyloxy group, butyryloxy group and the like. A 1 The divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by the following formula (I) is a group having one substituent or the same Alternatively, it may have a plurality of different substituents. A 1 -CH2- contained in the divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms is -O-, - It may be replaced by S-, -CO- or -SO2-. A 1 When the divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by the formula (I) has a substituent, or when the divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by the formula (I) has a substituent, -CH2- contained in the alicyclic hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2-. When the hydrocarbon group is substituted, the number of carbon atoms before substitution is regarded as the number of carbon atoms of the hydrocarbon group.

[0012] A 1 The divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms represented by the formula (I) is a cyclopentanediyl group. a monocyclic divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms, such as a cyclohexanediyl group (the alicyclic group -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-. or a group having 3 to 4 carbon atoms such as an adamantanediyl group or a norbornanediyl group. 18 polycyclic divalent alicyclic hydrocarbon group (-CH2- contained in the alicyclic hydrocarbon group is -O-, -S-, -CO- or -SO2- may be substituted. cyclopentanediyl group, cyclohexanediyl group, adamantanediyl group or nor A bornanediyl group is more preferred, and a cyclohexanediyl group or an adamantane A diyl group is more preferred.

[0013] R a The fluorinated alkyl group having 1 to 6 carbon atoms represented by the formula (I) is a group having one or more fluorine atoms. It represents an alkyl group having 1 to 6 carbon atoms, and is a trifluoromethyl group, a difluoromethyl group, a perfluoromethyl group, fluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group Ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, 3,3,3-trifluoropropyl group, perfluorobutyl group, 1,1,2,2,3,3 ,4,4-octafluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group butyl group, 3,3,4,4,4-pentafluorobutyl group, perfluoropentyl group, 2,2 ,3,3,4,4,5,5,5-nonafluoropentyl group, 3,3,4,4,5,5,5 -heptafluoropentyl group, 4,4,5,5,5-pentafluoropentyl group, perf fluorohexyl group, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl group, hexyl group, 3,3,4,4,5,5,6,6,6-nonafluorohexyl group and 4,4, 5,5,6,6,6-heptafluorohexyl group, and the like; trifluoromethyl group, Perfluoroethyl group, perfluoropropyl group, perfluorohexyl group, etc. Perfluoroalkyl groups of up to 6 are preferred, with trifluoromethyl groups being more preferred. R a is preferably a perfluoroalkyl group having 1 to 6 carbon atoms or a fluorine atom, A trifluoromethyl group or a fluorine atom is more preferred.

[0014] Examples of the anion (I) include the following anions: -1) to (Ia-4), (Ia-11), (Ia-14), and (Ia-15) The anions that are preferred are: TIFF0007672459000006.tif91134

[0015] TIFF0007672459000007.tif68164

[0016] Z + The organic cations include organic onium cations, organic sulfonium cations, Organic iodonium cations, organic ammonium cations, benzothiazolium cations and Among these, organic sulfonium cations are and organic iodonium cations are preferred, with arylsulfonium cations being more preferred. Specifically, the cation represented by any one of formulas (b2-1) to (b2-4) (hereinafter , and may be referred to as "cation (b2-1)" etc. depending on the formula number. TIFF0007672459000008.tif70107In equations (b2-1) to (b2-4), R b4 ~R b6 are each independently a chain hydrocarbon group having 1 to 30 carbon atoms, a chain hydrocarbon group having 3 to 36 carbon atoms, It represents an alicyclic hydrocarbon group or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the chain hydrocarbon group The hydrogen atoms contained in the alkyl group are hydroxyl groups, alkoxy groups with 1 to 12 carbon atoms, and alkyl groups with 3 to 12 carbon atoms. It may be substituted with a cyclic hydrocarbon group or an aromatic hydrocarbon group having 6 to 18 carbon atoms, The hydrogen atoms contained in the hydrocarbon group are halogen atoms, aliphatic hydrocarbon groups having 1 to 18 carbon atoms, may be substituted with an alkylcarbonyl group having 2 to 4 carbon atoms or a glycidyloxy group. The hydrogen atoms contained in the aromatic hydrocarbon group are replaced by halogen atoms, hydroxy groups, or groups having 1 carbon atom. It may be substituted with up to 12 alkoxy groups. R b4 and R b5 are bonded to each other and form a ring with the sulfur atom to which they are attached. -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. good. R b7 and R b8 are each independently a hydroxy group or an aliphatic hydrocarbon group having 1 to 12 carbon atoms. Or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of 0 to 5; When m2 is 2 or more, multiple R b7 may be the same or different, and when n2 is 2 or more, R in Numbers b8 may be the same or different. R b9 and R b10 are each independently a chain hydrocarbon group having 1 to 36 carbon atoms or a chain hydrocarbon group having 3 to 4 carbon atoms, Represents 36 alicyclic hydrocarbon groups. R b9 and R b10 are bonded to each other and form a ring with the sulfur atom to which they are attached -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. Good too. R b11 is a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, It represents a hydrogen group or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or It represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atoms contained in the chain hydrocarbon are It may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the aromatic hydrocarbon group The hydrogen atom is preferably an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyl group having 1 to 12 carbon atoms. It may be substituted with an oxy group. R b11 and R b12 are bonded to each other to form a ring including the -CH-CO- to which they are attached. -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. It is also possible. R b13 ~R b18 are each independently a hydroxy group or an aliphatic hydrocarbon group having 1 to 12 carbon atoms. Or an alkoxy group having 1 to 12 carbon atoms. L b31 represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of 0 to 5. q2 and r2 each independently represent an integer of 0 to 4; u2 represents 0 or 1. When o2 is 2 or more, multiple R b13 are the same or different, and when p2 is 2 or more, multiple R b14 are the same or different, and when q2 is 2 or more, multiple R b15 are the same or different, r2 When is 2 or more, multiple R b16 are the same or different, and when s2 is 2 or more, multiple R b17 teeth Identical or different, when t2 is 2 or more, multiple R b18 are the same or different.

[0017] The aliphatic hydrocarbon group refers to a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group. group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and An example of an alkyl group is a 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, and a monocyclic alicyclic hydrocarbon group may be Examples of the hydrogen group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. cycloalkyl groups such as cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl groups. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl and adamantyl groups. , norbornyl group, and the following groups. TIFF0007672459000009.tif11158 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably has 4 to 12 carbon atoms. Examples of alicyclic hydrocarbon groups in which hydrogen atoms are substituted with aliphatic hydrocarbon groups include methylcyclohexane. cyclohexyl group, dimethylcyclohexyl group, 2-methyladamantan-2-yl group, 2-ethyl 2-Isopropyladamantan-2-yl group, methylnor Examples of the alkyl group include a bornyl group and an isobornyl group. In the alicyclic hydrocarbon group, the total number of carbon atoms in the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 1. Preferably it is 20 or less. Examples of the aromatic hydrocarbon group include a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may be a chain hydrocarbon group or an alicyclic hydrocarbon group. Aromatic hydrocarbon groups (tolyl groups, hydroxyl groups, etc.) that may have hydrogen groups and have chain hydrocarbon groups aryl group, cumenyl group, mesityl group, p-ethylphenyl group, p-tert-butylphenyl group phenyl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.) and alicyclic Aromatic hydrocarbon groups containing hydrocarbon groups (p-cyclohexylphenyl group, p-adamantine phenyl group, etc.). In addition, when the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, A chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of aromatic hydrocarbon groups in which hydrogen atoms are substituted with alkoxy groups include p-methoxyphenyl. Examples thereof include a methyl group. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include a benzyl group, a phenyl group, and a phenyl group. ethyl group, phenylpropyl group, trityl group, naphthylmethyl group, naphthylethyl group, etc. Examples include aralkyl groups.

[0018] The alkoxy group includes a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, and the like. hydroxyl group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy groups. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. can be done. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. do. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group and an ethylcarbonyloxy group. Oxy group, propylcarbonyloxy group, isopropylcarbonyloxy group, butylcarbonyloxy group butylcarbonyloxy group, sec-butylcarbonyloxy group, tert-butylcarbonyloxy group silyl group, pentylcarbonyloxy group, hexylcarbonyloxy group, octylcarbonyl Examples include an oxy group and a 2-ethylhexylcarbonyloxy group.

[0019] R b4 and R b5 and bond together with the sulfur atom to which they are attached to form a ring The ring may be monocyclic, polycyclic, aromatic, non-aromatic, saturated or unsaturated. The ring may have 3 to 18 carbon atoms, and preferably has 4 to 18 carbon atoms. The ring containing a sulfur atom may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring. Examples include the rings shown below, where * represents a binding site. TIFF0007672459000010.tif26154R b9 and R b10 The ring formed by combining and can be monocyclic, polycyclic, aromatic, or non-aromatic. The ring may be either saturated or unsaturated. Examples of the ring include a 3-membered ring to a 12-membered ring. Preferably, it is a 3- to 7-membered ring. For example, a thiolan-1-ium ring (tetrahydrothio) thiophenium ring), thian-1-ium ring, 1,4-oxathian-4-ium ring, etc. It can be obtained. R b11 and R b12 The ring formed by combining and can be monocyclic, polycyclic, aromatic, or non-aromatic. The ring may be either saturated or unsaturated. Examples of the ring include a 3-membered ring to a 12-membered ring. and preferably a 3- to 7-membered ring. Oxocycloheptane ring, oxocyclohexane ring , oxonorbornane ring, oxoadamantane ring, etc.

[0020] Among the cations (b2-1) to (b2-4), the cation (b2 -1). Examples of the cation (b2-1) include the following cations. TIFF0007672459000011.tif79157

[0021] TIFF0007672459000012.tif74143

[0022] Examples of the cation (b2-2) include the following cations. TIFF0007672459000013.tif16120

[0023] Examples of the cation (b2-3) include the following cations. TIFF0007672459000014.tif25153

[0024] Examples of the cation (b2-4) include the following cations. TIFF0007672459000015.tif126147

[0025] Examples of the salt (I) include the salts listed in Table 1. For example, in Table 1, salt (I-1) is composed of an anion represented by formula (Ia-1) and a cation represented by formula (b2-c-1). The salt is shown below. TIFF0007672459000016.tif2878

[0026] [Table 1] TIFF0007672459000018.tif223151 TIFF0007672459000019.tif223151 TIFF0007672459000020.tif223151 TIFF0007672459000021.tif140149

[0027] Among them, salt (I) includes salt (I-1) to salt (I-4), salt (I-11), salt (I-14) ), Salt (I-15), Salt (I-16) ~ Salt (I-19), Salt (I-26), Salt (I-29) ), Salt (I-30) ~ Salt (I-34), Salt (I-41), Salt (I-44), Salt (I-45) ) ~ Salt (I-49), Salt (I-56), Salt (I-59), Salt (I-60) ~ Salt (I-64) ), Salt (I-71), Salt (I-74), Salt (I-75) ~ Salt (I-79), Salt (I-86) ), Salt (I-89), Salt (I-90) ~ Salt (I-94), Salt (I-101), Salt (I-1 04), Salt (I-105) ~ Salt (I-109), Salt (I-116), Salt (I-119), Salt (I-120) ~ Salt (I-124), Salt (I-131), Salt (I-134), Salt (I- 135), Salt (I-136) ~ Salt (I-139), Salt (I-146), Salt (I-149) , salt (I-150) is preferred.

[0028] <Method for producing salt (I)> In salt (I), X 1 However, the salt represented by formula (I1) is *-CO-O-. For example, the salt represented by formula (I1-a) is reacted with carbonyldiimidazole in a solvent. and then further reacting with a compound represented by formula (I1-b) can be done. TIFF0007672459000022.tif29155 (wherein all symbols have the same meanings as defined above.) Examples of solvents used in this reaction include chloroform and acetonitrile. The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 to 24 hours.

[0029] Examples of the salt represented by formula (I1-a) include the salts represented by the following formulas, and the salts are disclosed in Japanese Patent Application Laid-Open No. 2002-200344. It can be produced by referring to the method described in Publication No. 08-127367. TIFF0007672459000023.tif71132 Examples of the compound represented by formula (I1-b) include compounds represented by the following formula: It can be easily obtained from the market. TIFF0007672459000024.tif43121

[0030] In salt (I), X 1 is *-O-CO-O- (salt represented by formula (I2)) For example, the salt represented by formula (I2-a) is reacted with carbonyldiimidazole in a solvent. After reacting the compound with the compound represented by formula (I1-b), It is possible. The salt represented by formula (I2) can be prepared by, for example, reacting a compound represented by formula (I1-b) with a carbo and 2-(2-phenyl-2-isopropyl-2-methyl-2-propanol) in a solvent, and then reacting the compound with 2-(2-phenyl-2-isopropyl-2-methyl-2-propanol) in a solvent. It can also be produced by reacting TIFF0007672459000025.tif64164 (wherein all symbols have the same meanings as defined above.) Examples of solvents used in this reaction include chloroform and acetonitrile. The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 to 24 hours. Examples of the salt represented by formula (I2-a) include the salts represented by the following formulas, and the salts are disclosed in Japanese Patent Application Laid-Open No. 2002-200344. It can be produced by referring to the method described in Publication No. 12-193170. TIFF0007672459000026.tif71131

[0031] In salt (I), X 1However, a salt in which *-O-CO- is represented by the formula (I3) is For example, the compound represented by formula (I3-b) is reacted with carbonyldiimidazole in a solvent. and then further reacting with a salt represented by formula (I2-a). This can be done. TIFF0007672459000027.tif33167 (wherein all symbols have the same meanings as defined above.) Examples of solvents used in this reaction include chloroform and acetonitrile. The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 to 24 hours. The compound represented by formula (I3-b) includes compounds represented by the following formula: It can be easily obtained from the market. TIFF0007672459000028.tif1971

[0032] In salt (I), X 1 is -O- (salt represented by formula (I4)) -a) and a compound represented by formula (I1-b) in a solvent in the presence of a base. It can be obtained by reacting TIFF0007672459000029.tif23166 (wherein all symbols have the same meanings as defined above.) The base used in this reaction includes potassium hydroxide and the like. Examples of the solvent used in this reaction include acetonitrile. The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 to 24 hours.

[0033] In the salt (I), L 1 But *-L I4 -Ad-L I5 -O-CO-OL I6 -Yes A salt represented by formula (I5) (L I4 , LI5 and L I6 are, independently of each other, single bonds or an alkanediyl group having 1 to 6 carbon atoms; L I4 , L I5 and L I6 At least one of represents an alkanediyl group having 1 to 6 carbon atoms; Ad represents an adamantanediyl group; is X 1 represents the bonding position between, for example, a salt represented by formula (I5-a) and a salt represented by formula (I5-b The compound can be produced by reacting the compound represented by the formula (I) in a solvent. TIFF0007672459000030.tif54162 (wherein all symbols have the same meanings as defined above.) The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 to 24 hours. Examples of solvents used in this reaction include chloroform and acetonitrile. Examples of the salt represented by formula (I5-a) include the salts represented by the following formulas, and the salts are disclosed in Japanese Patent Application Laid-Open No. 2002-200344. It can be produced by the method described in Publication No. 12-72109. TIFF0007672459000031.tif26119The compound represented by formula (I5-b) is, for example, a compound represented by formula (I1-b). Examples include:

[0034] <Acid generator> The acid generator of the present invention is an acid generator containing the salt (I). The salt (I) may be used alone. Alternatively, two or more of them may be used in combination. In addition to the salt (I), the acid generator of the present invention may also include acid generators known in the resist field (hereinafter referred to as "acid generators"). The acid generator (B) may be used alone. Alternatively, two or more of them may be used in combination.

[0035] The acid generator (B) may be either a nonionic or ionic acid generator. Biocides include sulfonate esters (e.g., 2-nitrobenzyl esters, aromatic sulfonates, etc.). sulfonates, oximesulfonates, N-sulfonyloxyimides, sulfonyloxyketones ton, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfones, ketones Examples of ionic acid generators include ionic acid generators such as ionic acid generators (sulfones, sulfonyldiazomethanes, etc.). Onium salts containing ammonium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts) Typical examples of onium salts include sulfonate anions. anion, sulfonylimide anion, sulfonylmethide anion, etc. Examples of the acid generator (B) include those disclosed in JP-A-63-26653 and JP-A-55-164824; JP-A-62-69263, JP-A-63-146038, JP-A-63-163452 , JP 62-153853 A, JP 63-146029 A, U.S. Pat. No. 3,779, 778, U.S. Pat. No. 3,849,137, German Patent No. 3914407, European Patent No. Compounds that generate acids when exposed to radiation, such as those described in US Pat. No. 126,712, can be used. In addition, compounds produced by known methods may be used. The acid generator (B) may be a mixture of two or more compounds. They may also be used in combination.

[0036] The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a compound represented by the formula (B1): (hereinafter, may be referred to as "acid generator (B1)", excluding salt (I).) is. TIFF0007672459000032.tif2863[In formula (B1), Q b1 and Q b2are each independently a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. represents a methyl group. L b1 represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, and the divalent saturated hydrocarbon group The -CH2- contained in the carboxylic acid may be replaced by -O- or -CO-, and the divalent saturated carbon atom The hydrogen atom contained in the hydrogen group may be substituted with a fluorine atom or a hydroxy group. Y is a methyl group which may have a substituent or a C3-C1 8, and -CH2- contained in the alicyclic hydrocarbon group is -O-, - It may be replaced by S(O)2- or -CO-. Z1 + represents an organic cation.

[0037] Q b1 and Q b2 The perfluoroalkyl group represented by the formula (I) includes a trifluoromethyl group, a perfluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluoro butyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoro Examples include a perfluoropentyl group and a perfluorohexyl group. Q b1 and Q b2 are each independently a fluorine atom or a trifluoromethyl group. It is preferable that both are fluorine atoms.

[0038] L b1 The divalent saturated hydrocarbon group in and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups. A group formed by combining two or more of these may also be used. Specifically, 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- linear alkanediyl groups such as diyl groups; Ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group 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 branched alkanediyl groups such as 2-methylbutane-1,4-diyl groups; Cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexa cycloalkanediyl groups such as cyclohexene-1,4-diyl and cyclooctane-1,5-diyl a monocyclic divalent alicyclic saturated hydrocarbon group; Norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane- Polycyclic divalent alicyclic saturated carbons such as 1,5-diyl and adamantane-2,6-diyl groups Examples include a hydrogen group. L b1 The -CH2- contained in the divalent saturated hydrocarbon group represented by the formula: The substituted group may be, for example, a group represented by any one of formulas (b1-1) to (b1-3). In addition, the groups represented by formulae (b1-1) to (b1-3) and their specific examples are In the examples of groups represented by formulae (b1-4) to (b1-11), * and ** represent bonding sites. * represents the bond to -Y.

[0039] TIFF0007672459000033.tif26117 [In formula (b1-1), L b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, The hydrogen atoms contained in 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 carbon may be substituted with fluorine atoms or hydroxy groups. The -CH2- contained in the hydrogen hydride group may be replaced by -O- or -CO-. However, L b2 and L b3 The total number of carbon atoms is 22 or less. In formula (b1-2), L b4 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, The hydrogen atoms contained in 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 carbon may be substituted with fluorine atoms or hydroxy groups. The -CH2- contained in the hydrogen hydride group may be replaced by -O- or -CO-. However, L b4 and L b5 The total number of carbon atoms is 22 or less. In formula (b1-3), L b6 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, The hydrogen atoms contained in may be substituted with fluorine atoms or hydroxy groups. Lb7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, The hydrogen atoms contained in the saturated carbon may be substituted with fluorine atoms or hydroxy groups. The -CH2- contained in the hydrogen hydride group may be replaced by -O- or -CO-. However, L b6 and L b7 The total number of carbon atoms is 23 or less.

[0040] In the groups represented by formulae (b1-1) to (b1-3), - contained in the saturated hydrocarbon group When CH2- is replaced by -O- or -CO-, the number of carbon atoms before the replacement is The number of carbon atoms in the hydrocarbon group. As the divalent saturated hydrocarbon group, L b1 The divalent saturated hydrocarbon groups are the same as those of do.

[0041] L b2 is preferably a single bond. L b3 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b4 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms, and the divalent saturated hydrocarbon The hydrogen atoms contained in the group may be substituted with fluorine atoms. L b5 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b6 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms. 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 hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, The -CH2- contained in the divalent saturated hydrocarbon group is replaced with -O- or -CO-. Good too. L b1 The -CH2- contained in the divalent saturated hydrocarbon group represented by the formula: The substituted group is preferably a group represented by formula (b1-1) or formula (b1-3).

[0042] The group represented by formula (b1-1) includes those represented by formulas (b1-4) to (b1-8), respectively. Examples of such groups include: TIFF0007672459000034.tif48120[In formula (b1-4), L b8 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms, The hydrogen atoms contained in may be substituted with fluorine atoms or hydroxy groups. In formula (b1-5), L b9 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, and the divalent saturated hydrocarbon group The -CH2- contained therein 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, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b9 and L b10 The total number of carbon atoms is 20 or less. In formula (b1-6), L b11 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b12 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b11 and L b12 The total number of carbon atoms is 21 or less. In formula (b1-7), L b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. L b14 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, The -CH2- contained in the hydrogen hydride group may be replaced with -O- or -CO-. L b15 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b13 ~L b15 The total number of carbon atoms is 19 or less. In formula (b1-8), L b16 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the divalent saturated hydrocarbon group The contained -CH2- may be replaced by -O- or -CO-. L b17 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms. L b18 represents a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, The hydrogen atoms contained in the hydrogen hydride group may be substituted with fluorine atoms or hydroxy groups. However, L b16 ~L b18 The total number of carbon atoms is 19 or less.

[0043] L b8 is preferably a divalent saturated hydrocarbon group having 1 to 4 carbon atoms. L b9 is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b10 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms, and more preferably Preferably, it is a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b11is preferably a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b12 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b13 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b14 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b15 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and more preferably Preferably, it is a single bond or a divalent saturated hydrocarbon group having 1 to 8 carbon atoms. L b16 is preferably a divalent saturated hydrocarbon group having 1 to 12 carbon atoms. L b17 is preferably a divalent saturated hydrocarbon group having 1 to 6 carbon atoms. L b18 is preferably a single bond or a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and more preferably Preferably, it is a single bond or a divalent saturated hydrocarbon group having 1 to 4 carbon atoms.

[0044] The group represented by formula (b1-3) is represented by formulas (b1-9) to (b1-11), respectively. Examples include groups represented by the following formula: TIFF0007672459000035.tif23139 formula (b1-9), L b19 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, A hydrogen atom contained in the group may be substituted with a fluorine atom. L b20 represents a single bond or a divalent saturated hydrocarbon group having 1 to 23 carbon atoms, The hydrogen atoms contained in the group are substituted with fluorine atoms, hydroxy groups, or alkylcarbonyloxy groups. The —CH2— contained in the alkylcarbonyloxy group may be replaced by —O—. or -CO-, and the hydrogen contained in the alkylcarbonyloxy group The atom may be substituted with a hydroxy group. However, L b19 and L b20 The total number of carbon atoms is 23 or less. In formula (b1-10), L b21 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, A hydrogen atom contained in the group may be substituted with a fluorine atom. L b22 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b23 represents a single bond or a divalent saturated hydrocarbon group having 1 to 21 carbon atoms, The hydrogen atoms contained in the group are substituted with fluorine atoms, hydroxy groups, or alkylcarbonyloxy groups. The —CH2— contained in the alkylcarbonyloxy group may be replaced by —O—. or -CO-, and the hydrogen contained in the alkylcarbonyloxy group The atom may be substituted with a hydroxy group. However, L b21 , L b22 and L b23 The total number of carbon atoms is 21 or less. In formula (b1-11), L b24 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, A hydrogen atom contained in the group may be substituted with a fluorine atom. L b25 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. L b26 represents a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms, The hydrogen atoms contained in the group are substituted with fluorine atoms, hydroxy groups, or alkylcarbonyloxy groups. The —CH2— contained in the alkylcarbonyloxy group may be replaced by —O—. or -CO-, and the hydrogen contained in the alkylcarbonyloxy group The atom may be substituted with a hydroxy group. However, L b24 , L b25 and L b26 The total number of carbon atoms is 21 or less. In addition, in the groups represented by formula (b1-9) to formula (b1-11), saturated When a hydrogen atom contained in a mono- or di-hydrocarbon group is substituted with an alkylcarbonyloxy group, The number of carbon atoms before substitution is the number of carbon atoms of the saturated hydrocarbon group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a bromide group, and a bromine group. Thyryloxy group, cyclohexylcarbonyloxy group, adamantylcarbonyloxy group etc.

[0045] Examples of the group represented by formula (b1-4) include the following. TIFF0007672459000036.tif16154

[0046] Examples of the group represented by formula (b1-5) include the following. TIFF0007672459000037.tif78163

[0047] Examples of the group represented by formula (b1-6) include the following. TIFF0007672459000038.tif53148

[0048] Examples of the group represented by formula (b1-7) include the following. TIFF0007672459000039.tif62153

[0049] Examples of the group represented by formula (b1-8) include the following. TIFF0007672459000040.tif23150

[0050] Examples of the group represented by formula (b1-2) include the following. TIFF0007672459000041.tif31161

[0051] Examples of the group represented by formula (b1-9) include the following. TIFF0007672459000042.tif44137

[0052] Examples of the group represented by formula (b1-10) include the following. TIFF0007672459000043.tif92166

[0053] Examples of the group represented by formula (b1-11) include the following. TIFF0007672459000044.tif85164

[0054] The alicyclic hydrocarbon group represented by Y includes those represented by formula (Y1) to formula (Y11), formula (Y36) to formula (Y37) Examples include a group represented by formula (Y38). The —CH2— contained in the alicyclic hydrocarbon group represented by Y is —O—, —S(O)2— or — When the group is replaced with CO-, the number of CO- may be one or more. Examples of the group include groups represented by formulae (Y12) to (Y35), (Y39) and (Y40). * is L b1 represents the bonding position with

[0055] The alicyclic hydrocarbon group represented by TIFF0007672459000045.tif85166Y is preferably a group represented by formula (Y1) to formula (Y20), Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y39) to formula (Y41) and more preferably a group represented by formula (Y11), formula (Y15), or formula (Y16 ), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula (Y 39) or a group represented by formula (Y40), and more preferably a group represented by formula (Y11), formula (Y1 5), formula (Y20), formula (Y26), formula (Y27), formula (Y30), formula (Y31), formula ( Y39) or a group represented by formula (Y40). The alicyclic hydrocarbon group represented by Y is selected from the group consisting of the formulae (Y28) to (Y35), the formulae (Y39) to (Y In the case of a spiro ring containing an oxygen atom such as 40), an alkanediyl group between the two oxygen atoms is used. The group preferably has one or more fluorine atoms. In the candiyl group, the methylene group adjacent to the oxygen atom is not substituted with a fluorine atom. It is preferable to have

[0056] The substituent of the methyl group represented by Y is a halogen atom, a hydroxyl group, a methyl group having 3 to 1 carbon atoms, or 6 alicyclic hydrocarbon groups, aromatic hydrocarbon groups having 6 to 18 carbon atoms, glycidyloxy groups, -( CH2) ja -CO-OR b1 group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1 teeth, an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or an alicyclic hydrocarbon group having 6 to 18 carbon atoms; represents an aromatic hydrocarbon group or a group in which these groups are combined; ja is an integer of 0 to 4; It is included in the alkyl group having 1 to 16 carbon atoms and the alicyclic hydrocarbon group having 3 to 16 carbon atoms. -CH2- may be replaced by -O-, -S(O)2- or -CO-.) Examples include: The substituent of the alicyclic hydrocarbon group represented by Y is a halogen atom, a hydroxy group, a hydroxyl group ... an alkyl group having 1 to 12 carbon atoms which may be substituted with an alkyl group having 3 to 16 carbon atoms; Hydrocarbon groups, alkoxy groups having 1 to 12 carbon atoms, aromatic hydrocarbon groups having 6 to 18 carbon atoms, carbon Aralkyl groups having 7 to 21 carbon atoms, alkylcarbonyl groups having 2 to 4 carbon atoms, and glycidyloxy groups. , -(CH2) ja -CO-OR b1 group or -(CH2) ja -O-CO-R b1 group (in the formula, R b1 is an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or a 18 aromatic hydrocarbon groups or groups combining these. ja is any of 0 to 4. It represents an integer of 1 to 16 carbon atoms in an alkyl group and 3 to 16 carbon atoms in an alicyclic hydrocarbon group. The -CH2- contained therein may be replaced by -O-, -S(O)2- or -CO-. .) etc.

[0057] Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. do. Examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, and a cyclohexyl group. cyclohexyl group, dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, Examples include a carboxyl group and an adamantyl group. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and the like. Examples of aromatic hydrocarbon groups include aryl groups such as an alkyl group and a phenanthryl group. The aromatic hydrocarbon group may have a hydrocarbon group or an alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a chain hydrocarbon group. Hydrogen groups (tolyl group, xylyl group, cumenyl group, mesityl group, p-methylphenyl group, p- Ethylphenyl group, p-tert-butylphenyl group, 2,6-diethylphenyl group, 2 -methyl-6-ethylphenyl group, etc.) and aromatic hydrocarbon groups having alicyclic hydrocarbon groups ( p-cyclohexylphenyl group, p-adamantylphenyl group, etc. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a bromine group. butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group , 2-ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group etc. Examples of alkyl groups substituted with hydroxy groups include hydroxymethyl groups, hydroxy Examples include hydroxyalkyl groups such as an ethyl group. The alkoxy group includes a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, and the like. hydroxyl group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy groups. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and the like. Examples include an ethyl group and a naphthylethyl group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. etc.

[0058] Examples of Y include the following: TIFF0007672459000046.tif107163

[0059] TIFF0007672459000047.tif33150

[0060] Y is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent. More preferably, it is an adamantyl group which may have a substituent, and the alicyclic hydrocarbon group or -CH2- constituting the adamantyl group is replaced with -CO-, -S(O)2- or -CO-. Y is more preferably an adamantyl group or a hydroxyadamantyl group. group, an oxoadamantyl group, or a group represented by the following formula: TIFF0007672459000048.tif89156

[0061] The anion in the salt represented by formula (B1) includes the anions represented by formula (B1-A-1) to formula (B1- A-55) (hereinafter, "anion (B1-A-1)" and so on according to the formula number) Formula (B1-A-1) to Formula (B1-A-4), Formula (B1 -A-9), formula (B1-A-10), formula (B1-A-24) ~ formula (B1-A-33), formula (B1-A-36) ~ Formula (B1-A-40), Formula (B1-A-47) ~ Formula (B1-A-5 5) is more preferred.

[0062] TIFF0007672459000049.tif157169

[0063] TIFF0007672459000050.tif85146 TIFF0007672459000051.tif138166

[0064] TIFF0007672459000052.tif70167

[0065] TIFF0007672459000053.tif118154

[0066] TIFF0007672459000054.tif118137 TIFF0007672459000055.tif63155

[0067] where R i2 ~Ri7 are each independently, for example, an alkyl group having 1 to 4 carbon atoms, preferably R is a methyl group or an ethyl group. i8 is, for example, a chain hydrocarbon group having 1 to 12 carbon atoms, preferably or an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a combination thereof. A group formed by reacting a methyl group with a cyclohexyl group is more preferred. is an adamantyl group. A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms Q b1 and Q b2 has the same meaning as above. Specific examples of the anion in the salt represented by formula (B1) include those described in JP-A-2010-20 Examples of anions include those described in JP-A-4646.

[0068] The anion in the salt represented by formula (B1) is preferably a compound represented by formula (B1a-1) to formula (B1a-2). B1a-34) are examples of anions. TIFF0007672459000056.tif126154

[0069] TIFF0007672459000057.tif97145

[0070] TIFF0007672459000058.tif130146

[0071] TIFF0007672459000059.tif81162

[0072] Among them, the compounds represented by formula (B1a-1) to formula (B1a-3) and formula (B1a-7) to formula (B1a- 16), formula (B1a-18), formula (B1a-19), formula (B1a-22) ~ formula (B1a- 34) is preferred.

[0073] Z1+ Examples of the organic cation include organic onium cations, organic sulfonium cations, Organic iodonium cations, organic ammonium cations, benzothiazolium cations, and Among these, organic sulfonium cations are Preferred are iodonium and organic iodonium cations, and more preferred are arylsulfonium cations. It's nice. Z1 in formula (B1) + The cation (I) in the salt (I) can be the same as the cation (I). .

[0074] The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, The acid generator (B) is preferably a compound represented by the formula (B1a-1) to Formula (B1a-3), Formula (B1a-7) ~ Formula (B1a-16), Formula (B1a-18), Formula ( B1a-19), an anion represented by any one of formulas (B1a-22) to (B1a-34) Examples of the combination include a combination of an anion and a cation (b2-1) or a cation (b2-3).

[0075] The acid generator (B) is preferably a compound represented by formula (B1-1) to formula (B1-48), Among them, those containing an arylsulfonium cation are preferred. Formula (B1-1) ~ Formula (B1-3), Formula (B1-5) ~ Formula (B1-7), Formula (B1-11) ~Formula (B1-14), Formula (B1-20) ~Formula (B1-26), Formula (B1-29), Formula (B Those represented by formulas (1-31) to (B1-48) are particularly preferred. TIFF0007672459000060.tif62150

[0076] TIFF0007672459000061.tif72164

[0077] TIFF0007672459000062.tif85161

[0078] TIFF0007672459000063.tif69165

[0079] TIFF0007672459000064.tif172161

[0080] TIFF0007672459000065.tif159148

[0081] When the acid generator contains a salt (I) and an acid generator (B), the salt (I) and the acid generator (B) The ratio of the salt (I):acid generator (B) content (mass ratio; salt (I):acid generator (B)) is usually 1:99 to 99:1. The ratio is preferably 2:98 to 98:2, and more preferably 5:95 to 95:5. , more preferably 10:90 to 90:10, and particularly preferably 15:85 to 85: It is 15.

[0082] <Resist composition> The resist composition of the present invention comprises an acid generator containing a salt (I) and a resin having an acid labile group (hereinafter referred to as Here, the "acid labile group" refers to a group that is detached from the resin (hereinafter referred to as "resin (A)"). When contacted with an acid, the leaving group is eliminated, and the structural unit is converted into a hydrophilic group (e.g., a hydroxyl group). It means a group that converts into a structural unit having a hydroxyl group (a hydroxyl group or a carboxyl group). The resist composition of the present invention generates an acid that is weaker in acidity than the acid generated from the acid generator. It may contain a quencher such as salt (hereinafter referred to as "quencher (C)"). It is preferable that the ink contains a solvent (hereinafter, sometimes referred to as "solvent (E)").

[0083] <Resin (A)> The resin (A) contains a structural unit having an acid labile group (hereinafter, sometimes referred to as "structural unit (a1)"). The resin (A) may further contain a structural unit other than the structural unit (a1). The structural unit other than the structural unit (a1) is preferably a structural unit ( (hereinafter sometimes referred to as "structural unit (s)"), structural unit (a1) and structural unit (s) other than (for example, a structural unit having a halogen atom described later (hereinafter referred to as "structural unit (a4) "), a structural unit having a non-leaving hydrocarbon group (hereinafter referred to as "structural unit ( a5)) and other structural units derived from monomers known in the art Examples include:

[0084] <Structural unit (a1)> The structural unit (a1) is a monomer having an acid labile group (hereinafter referred to as "monomer (a1)"). (in some cases). The acid labile group contained in the resin (A) is 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)) is preferred. TIFF0007672459000066.tif2298[In formula (1), R a1 , R a2 and R a3 are each independently an alkyl group having 1 to 8 carbon atoms, represents an alicyclic hydrocarbon group having 3 to 20 carbon atoms or a group combining these, or R a1 and R a2 are bonded to each other and together with the carbon atoms to which they are bonded form an alicyclic hydrocarbon group having 3 to 20 carbon atoms Form. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bond.] TIFF0007672459000067.tif2378[In formula (2), R a1' and R a2' are each independently a hydrogen atom or a carbon atom having 1 to 12 carbon atoms, represents a hydrogen hydride group, and R a3' represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2' and R a3' Mutually They bond to each other to form a heterocyclic group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X. -CH2- contained in the hydrocarbon group and the heterocyclic group is replaced by -O- or -S-. It is also possible. X represents an oxygen atom or a sulfur atom. na' represents 0 or 1. * represents a bond.]

[0085] R a1 , R a2 and R a3 Examples of the alkyl group in the formula (I) include a methyl group, an ethyl group, a propyl group, Examples include a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cyclohexyl group, and a cyclohexyl group. cycloalkyl groups such as butyl and cyclooctyl groups. Examples of the substituent include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following group ( * represents a bond.) etc. a1 , R a2 and R a3 The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16. TIFF0007672459000068.tif10159 Examples of the group combining an alkyl group and an alicyclic hydrocarbon group include methylcyclohexane. xyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group , adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc. do. Preferably, ma is 0 and na is 1. R a1 and R a2 -C(R a1 )(R a2 )(R a3 The alicyclic hydrocarbon group preferably has 3 carbon atoms. ~12. * represents a bond to -O-. TIFF0007672459000069.tif35158

[0086] R a1' , R a2' and R a3' The hydrocarbon group in the formula (I) may be an alkyl group or an alicyclic hydrocarbon group. , aromatic hydrocarbon groups, and groups formed by combining these groups. The alkyl group and the alicyclic hydrocarbon group are represented by R a1 , R a2 and R a3 The same groups as those listed in It can be obtained. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, Examples include aryl groups such as a phenanthryl group. The combined group may be a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined. (e.g., cycloalkylalkyl groups), aralkyl groups such as benzyl groups, alkyl groups Aromatic hydrocarbon groups (p-methylphenyl, p-tert-butylphenyl, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl- 6-ethylphenyl group, etc.), aromatic hydrocarbon groups with alicyclic hydrocarbon groups (p-cyclohexane adamantylphenyl group, p-adamantylphenyl group, phenylcyclohexyl group, etc. Examples thereof include an aryl-cyclohexyl group. R a2' and R a3' are bonded to each other to form a complex with the carbon atoms to which they are bonded and X. Examples of the heterocyclic group include the following groups: * represents a bond. TIFF0007672459000070.tif18124R a1' and R a2' At least one of these is preferably a hydrogen atom. na' is preferably 0.

[0087] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 is an alkyl group, ma=0, and na=1 A group represented by the formula: Preferably, the group is a tert-butoxycarbonyl group. In formula (1), R a1 , R a2 However, together with the carbon atoms to which they are bonded, they form adamannes Forms a methyl group, R a3 is an alkyl group, ma=0, and na=1. In formula (1), R a1 and R a2 are each independently an alkyl group, and R a3 Adama A group in which ma=0 and na=1. Specific examples of the group (1) include the following: * represents a bond. TIFF0007672459000071.tif48157 TIFF0007672459000072.tif45147

[0088] Specific examples of group (2) include the following groups: * represents a bond. TIFF0007672459000073.tif74154

[0089] The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond. More preferably, it is a (meth)acrylic monomer having an acid labile group.

[0090] Among the (meth)acrylic monomers having an acid labile group, those having 5 to 20 carbon atoms are preferred. Examples of the compound having a bulky structure such as an alicyclic hydrocarbon group include: A resin (A) having a structural unit derived from a monomer (a1) having the above structure is used in a resist composition. This can improve the resolution of the resist pattern.

[0091] As the structural unit derived from a (meth)acrylic monomer having the group (1), preferably , a structural unit represented by formula (a1-0) (hereinafter, may be referred to as structural unit (a1-0) ), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1) ) or a structural unit represented by formula (a1-2) (hereinafter, referred to as structural unit (a1-2) Preferably, the structural unit (a1-1) and the structural unit (a1-2) are These may be used alone. Two or more of these may be used in combination. TIFF0007672459000074.tif46149 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or -O-(CH2) k1 -CO- represents O-, k1 represents an integer of 1 to 7, and * represents a bond to -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 are each independently an alkyl group having 1 to 8 carbon atoms, 18 alicyclic hydrocarbon groups or groups combining these groups. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic group having 3 to 18 carbon atoms, represents a hydrocarbon group of the formula: or a group formed by combining these. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

[0092] R a01 , R a4 and R a5 is preferably a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or —O—(CH2) k01 -CO-O- (wherein k01 is preferably an integer of 1 to 4, more preferably 1) ), more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a7 alkyl groups, alicyclic hydrocarbon groups and the like Examples of the group combining these include R a1 , R a2 and R a3 The same groups as those listed in can be. R a02 , Ra03 , and R a04 The alkyl group in the formula (I) preferably has 1 to 6 carbon atoms, and more preferably More preferably, it is a methyl group or an ethyl group, and even more preferably, it is a methyl group. R a6 and R a7 The alkyl group in the formula (I) preferably has 1 to 6 carbon atoms, and more preferably has 1 to 6 carbon atoms. It is preferably a methyl group, an ethyl group, or an isopropyl group, and more preferably an ethyl group or an isopropyl group. It is a pyridyl group. R a02 , R a03 , R a04 , R a6 and R a7 The number of carbon atoms in the alicyclic hydrocarbon group is preferably 5 to 12, and more preferably 5 to 10. The group in which an alkyl group and an alicyclic hydrocarbon group are combined is The total number of carbon atoms in combination with the group is preferably 18 or less. R a02 and R a03 is preferably an alkyl group having 1 to 6 carbon atoms, more preferably methyl The alkyl group is an alkyl group or an ethyl group. R a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon having 5 to 12 carbon atoms. group, more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group. be. R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms, more preferably methyl group, an ethyl group, or an isopropyl group, and more preferably an ethyl group or an isopropyl group. is. m1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1' is preferably 0 or 1.

[0093] Examples of the structural unit (a1-0) include those represented by the formulae (a1-0-1) to (a1-0-12): and R in the structural unit (a1-0) a01 Methionine equivalent The structural units of the formula (a1-0-1) to the formula (a1-0) are exemplified by those in which a methyl group is replaced with a hydrogen atom. -10) is preferred. TIFF0007672459000075.tif58150

[0094] Examples of the structural unit (a1-1) include those described in JP-A-2010-204646. Among them, structural units derived from the monomers of formula (a1-1-1) to formula (a1 -1-4) and R in the structural unit (a1-1) a4 Equivalent to Structural units in which the methyl group is replaced with a hydrogen atom are preferred, and those represented by the formulas (a1-1-1) to ( A structural unit represented by any one of a1-1-4) is more preferred. TIFF0007672459000076.tif48131

[0095] The structural unit (a1-2) is any one of the structural units represented by formula (a1-2-1) to formula (a1-2-6). and R in the structural unit (a1-2) a5 The methyl group corresponding to The structural units are represented by the formula (a1-2-2), the formula (a1-2-5) and the formula (a1-2-6) is preferred. TIFF0007672459000077.tif37161

[0096] When the resin (A) contains the structural unit (a1-0), its content is determined based on the total structural units of the resin (A). It is usually 5 to 60 mol %, preferably 5 to 50 mol %, more preferably The content is usually 10 to 40 mol %. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), The total content of these is usually 10 to 95 mol % based on the total structural units of the resin (A), and preferably It is preferably 15 to 90 mol %, more preferably 20 to 85 mol %, and even more preferably Preferably, it is 25 to 80 mol %, and even more preferably, it is 30 to 75 mol %.

[0097] The structural unit (a1) having the group (2) is represented by the formula (a1-4). Examples of such structural units include those (hereinafter, may be referred to as "structural unit (a1-4)"). TIFF0007672459000078.tif3766[In formula (a1-4), R a32 is a hydrogen atom, a halogen atom, or a C1-6 alkyl group optionally having a halogen atom represents an alkyl group represented by the formula: R a33 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a Alkoxy group, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms represents an acryloyloxy group, an acryloyloxy group, or a methacryloyloxy group. la represents an integer of 0 to 4. When la is 2 or more, a plurality of R a33 are mutual may be the same or different. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are combined with each other and These form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -CO- to which they are bonded, and the hydrocarbon The -CH2- contained in the alkyl group and the divalent hydrocarbon group is replaced by -O- or -S-. That's fine.]

[0098] R a32 and R a33 The alkyl group in the formula (I) is a methyl group, an ethyl group, a propyl group, an iso ... Examples of the alkyl group include a propyl group, a butyl group, a pentyl group, and a hexyl group. An alkyl group having 1 to 4 prime numbers is preferred, a methyl group or an ethyl group is more preferred, and a methyl group is Even more preferable. R a32 and R a33 Examples of the halogen atom in the formula (I) include a fluorine atom, a chlorine atom, and a bromine atom. Examples include: Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoro Ethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group group, 1,1,2,2,3,3,4,4-octafluorobutyl group, butyl group, perfluoro 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, Examples of the alkyl group include an alkyl group, a hexyl group, and a perfluorohexyl group. The alkoxy group includes a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, and the like. Among them, alkoxy groups having 1 to 4 carbon atoms are particularly preferred. A methoxy group or an ethoxy group is more preferred, and a methoxy group is even more preferred. . Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. can be. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, a bromide group, and a bromine group. Examples thereof include a thyryloxy group. R a34 , R a35 and R a36 The hydrocarbon group in the formula (I) may be an alkyl group or an alicyclic hydrocarbon group. , aromatic hydrocarbon groups, and groups combining these. Examples of alkyl groups include methyl, ethyl, propyl, butyl, pentyl, and hexyl. Examples include a sil group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the cyclopentyl group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthalene, butyl group, adamantyl group, norbornyl group, and the following groups (* indicates a bonding site): Examples include: TIFF0007672459000079.tif10152Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, biphenyl, Examples include aryl groups such as a phenanthryl group. The combined group may be a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined. (e.g., cycloalkylalkyl groups), aralkyl groups such as benzyl groups, alkyl groups Aromatic hydrocarbon groups (p-methylphenyl, p-tert-butylphenyl, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl- 6-ethylphenyl group, etc.), aromatic hydrocarbon groups with alicyclic hydrocarbon groups (p-cyclohexane adamantylphenyl group, p-adamantylphenyl group, phenylcyclohexyl group, etc. In particular, R a36 As for carbon number 1 to 18, alkyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or Examples of groups include groups formed by combining these.

[0099] In formula (a1-4), R a32 is preferably a hydrogen atom. R a33 As the alkoxy group, an alkoxy group having 1 to 4 carbon atoms is preferred, and a methoxy group and an ethoxy group are also preferred. is more preferred, and a methoxy group is even more preferred. la is preferably 0 or 1, and more preferably 0. R a34 is preferably a hydrogen atom. R a35 is preferably an alkyl group or an alicyclic hydrocarbon group having 1 to 12 carbon atoms, more preferably More preferably, it is a methyl group or an ethyl group. R a36 The hydrocarbon group is preferably an alkyl group having 1 to 18 carbon atoms, a Alicyclic hydrocarbon groups, aromatic hydrocarbon groups having 6 to 18 carbon atoms, or combinations thereof More preferably, it is a group formed by an alkyl group having 1 to 18 carbon atoms, a group formed by an alkyl group having 3 to 1 carbon atoms, R is an alicyclic aliphatic hydrocarbon group having 8 carbon atoms or an aralkyl group having 7 to 18 carbon atoms. a36 in The alkyl group and the alicyclic hydrocarbon group are preferably unsubstituted. a36 in The aromatic hydrocarbon group is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0100] -OC(R a34 )(R a35 )-ORa36 is an acid (e.g. p-toluenesulfonic acid), it is eliminated to form a hydroxy group.

[0101] Examples of the structural unit (a1-4) include those described in JP-A-2010-204646. The structural units derived from the monomers of formula (a1-4-1) to formula (a1-4-2) are preferred. -4-12) and R in the structural unit (a1-4) a32 In accordance with A structural unit in which the corresponding hydrogen atom is replaced by a methyl group is preferred, and a structural unit represented by the formula (a 1-4-1) to (a1-4-5), and structural units represented by formula (a1-4-10) Examples include: TIFF0007672459000080.tif69157

[0102] When the resin (A) has the structural unit (a1-4), the content thereof is determined based on the total structure of the resin (A). It is preferably 10 to 95 mol %, more preferably 15 to 90 mol %, based on the total of the structural units. It is more preferable that the content is 20 to 85 mol %, and further more preferable that the content is 20 to 70 mol %. %, and particularly preferably 20 to 60 mol %.

[0103] The structural unit derived from a (meth)acrylic monomer having the group (2) includes a structural unit represented by the formula (a1 -5) (hereinafter sometimes referred to as "structural unit (a1-5)") can be. TIFF0007672459000081.tif4253 formula (a1-5), R a8 is an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Represents an atom. Z a1 is a single bond or -(CH2) h3-CO-L 54 -, h3 is 1 to 4 represents an integer, and * represents L 51 Represents a bond with . L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-. s1 represents an integer of 1 to 3. s1' represents an integer of 0 to 3.

[0104] Examples of halogen atoms include fluorine atoms and chlorine atoms, with fluorine atoms being preferred. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include a methyl group and an ethyl group. , propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, fluoro Examples include methyl and trifluoromethyl groups. In formula (a1-5), R a8 is a hydrogen atom, a methyl group, or a trifluoromethyl group preferable. L 51 is preferably an oxygen atom. L 52 and L 53 Among these, it is preferred that one is —O— and the other is —S—. s1 is preferably 1. s1' is preferably an integer of 0 to 2. Z a1 is preferably a single bond or —CH2—CO—O—.

[0105] Examples of the structural unit (a1-5) include those described in JP-A-2010-61117. Among them, structural units derived from the monomers of formula (a1-5-1) to formula (a1-5- 4), and the structural units represented by formula (a1-5-1) or formula (a1-5-2) are preferred. ) is more preferred. TIFF0007672459000082.tif31129

[0106] When the resin (A) has the structural unit (a1-5), the content thereof is determined based on the total structure of the resin (A). The content is preferably 1 to 50 mol %, more preferably 3 to 45 mol %, and more preferably 5 to 40 mol %, based on the structural units. % by mole is more preferable, and 5 to 30 mol % is even more preferable.

[0107] Further, examples of the structural unit (a1) include the following structural units. TIFF0007672459000083.tif27161

[0108] When the resin (A) contains structural units such as those of (a1-3-1) to (a1-3-7) The content thereof is preferably 10 to 95 mol % based on the total structural units of the resin (A), and more preferably 15 to 95 mol %. More preferably, the content is 20 to 90 mol %, even more preferably, 20 to 85 mol %, and 20 to 70 mol %. It is even more preferable, 20 to 60 mol % is even more preferable, and 10 to 40 mol % is particularly preferable. I wish.

[0109] <Structural unit(s)> The structural unit (s) is a monomer that does not have an acid labile group (hereinafter referred to as "monomer (s)"). The monomer from which the structural unit (s) is derived is an acid-inhibiting monomer known in the resist field. Monomers without stabilizing groups can be used. The structural unit (s) preferably has a hydroxy group or a lactone ring. A structural unit having an oxy group and not having an acid labile group (hereinafter referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and no acid labile group (hereinafter referred to as "structural unit"). When a resin having the structural unit (a3) ​​is used in the resist composition of the present invention, This can improve the resolution of the resist pattern and the adhesion to the substrate.

[0110] <Structural unit (a2)> The hydroxy group of the structural unit (a2) may be an alcoholic hydroxy group or a phenolic hydroxy group. It may also be a hydroxyl group. When a resist pattern is produced from the resist composition of the present invention, KrF is used as the exposure light source. High energy rays such as excimer laser (248 nm), electron beam, or EUV (extreme ultraviolet) are used. In this case, the structural unit (a2) may be a structural unit having a phenolic hydroxy group ( It is preferable to use a2). In addition, it is also preferable to use an ArF excimer laser (193 nm) or the like. In this case, the structural unit (a2) may be the structural unit (a2-1) described later or the structural unit (a2-2) described later. It is more preferable to use the position (a2-A). It may contain one or more of these.

[0111] The structural unit (a2) having a phenolic hydroxy group includes the structural unit represented by the formula (a2 -A) (hereinafter sometimes referred to as "structural unit (a2-A)"). can be. TIFF0007672459000084.tif3843[In formula (a2-A), R a50 is a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. represents an alkyl group. R a51 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a Alkoxy group, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms represents an acryloyloxy group, an acryloyloxy group, or a methacryloyloxy group. A a50 is a single bond or *-Xa51 -(A a52 -X a52 ) nb - represents -R a50 is combined represents the bond to the carbon atom. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, multiple R in Numbers a51 may be the same or different from each other.]

[0112] R a50 Examples of the halogen atom in the formula (I) include a fluorine atom, a chlorine atom, and a bromine atom. can be. R a50 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom is, for example, tri Fluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2 -trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoroethyl group 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluoropropyl group Fluorobutyl 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 Examples include ethyl, pentyl, hexyl and perfluorohexyl groups. R a50 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and is more preferably an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a51The alkyl group in the formula (I) is a methyl group, an ethyl group, a propyl group, an isopropyl group, or the like. Examples of the butyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl group are listed below. can be done. R a51 The alkoxy group in the formula (I) is a methoxy group, an ethoxy group, a propoxy group, an isopropyl ... Examples include a propoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. An alkoxy group having 1 to 4 carbon atoms is preferred, a methoxy group or an ethoxy group is more preferred, and a methyl group is more preferred. A hydroxy group is more preferred. R a51 The alkylcarbonyl group in the formula (I) includes an acetyl group, a propionyl group, and a butyl group. Examples thereof include an aryl group. R a51 The alkylcarbonyloxy group in the formula (I) is an acetyloxy group, a propionyloxy group, or Examples of such groups include an aryloxy group and a butyryloxy group. R a51 is preferably a methyl group.

[0113] *-X a51 -(A a52 -X a52 ) nb - includes *-O-, *-CO-O-, *-OC O-, *-CO-OA a52 -CO-O-, *-O-CO-A a52 -O-, *-OA a52 -CO-O-, *-CO-OA a52 -O-CO-, *-O-CO-A a52 -O-CO-, Among them, *-CO-O- and *-CO-OA are a52 -CO-O- or *- Office Automation a52 -CO-O- is preferred.

[0114] Examples of the alkanediyl group include a methylene group, an ethylene group, and a propane-1,3-diyl group. Propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group , hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1, 3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group and and 2-methylbutane-1,4-diyl group. A a52 is preferably a methylene group or an ethylene group.

[0115] A a50 is a single bond, *-CO-O- or *-CO-OA a52 -CO-O- Preferably, it is a single bond, *-CO-O-, or *-CO-O-CH2-CO-O-. A single bond or *-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred.

[0116] mb is preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0. The hydroxy group is preferably bonded to the ortho- or para-position of the benzene ring, and more preferably to the para-position. It is more preferred to bind to

[0117] Examples of the structural unit (a2-A) include those described in JP-A-2010-204634 and JP-A-2012- Examples of structural units include those derived from monomers described in Japanese Patent Publication No. 12577. The structural unit (a2-A) is represented by the formulas (a2-2-1) to (a2-2-6). In the structural units and the structural units represented by formulas (a2-2-1) to (a2-2-6), R in units (a2-A) a50 A structural unit in which a methyl group corresponding to The structural unit (a2-A) includes a structural unit represented by the formula (a2-2-1), a structural unit represented by the formula ( a2-2-3), a structural unit represented by formula (a2-2-6) and a structural unit represented by formula (a 2-2-1), a structural unit represented by formula (a2-2-3), or a structural unit represented by formula (a2 -2-6), R in the structural unit (a2-A) a50 Equivalent to Preferably, the structural unit is a structural unit in which a methyl group is substituted for a hydrogen atom. TIFF0007672459000085.tif42166

[0118] Content of structural unit (a2-A) when structural unit (a2-A) is contained in resin (A) is preferably 5 to 80 mol %, more preferably 10 to 70 mol %, based on all structural units. % by mole, more preferably 15 to 65 mol %, and even more preferably 20 to 65 mol %. It is preferably 65 mol %, and more preferably 20 to 50 mol %. The structural unit (a2-A) can be prepared by polymerizing, for example, the structural unit (a1-4) described below, followed by It can be incorporated into resin (A) by treating it with an acid such as p-toluenesulfonic acid. In addition, after polymerization using acetoxystyrene, etc., tetramethylammonium hydroxide is used. By treating with an alkali such as benzoxazole, the structural unit (a2-A) is incorporated into the resin (A). It is possible.

[0119] The structural unit (a2) having an alcoholic hydroxy group includes a structural unit represented by the formula ( a2-1) (hereinafter referred to as "structural unit (a2-1)") Examples include: TIFF0007672459000086.tif3753 formula (a2-1), L a3 is -O- or *-O-(CH2) k2 represents -CO-O-, k2 represents an integer of 1 to 7. * represents a bond to —CO—. R a14 represents a hydrogen atom or a methyl group. R a15 and R a16 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. o1 represents an integer between 0 and 10.

[0120] In equation (a2-1), L a3 is preferably -O-, -O-(CH2) f1 -CO-O- (wherein f1 represents an integer of 1 to 4), and more preferably —O—. R a14 is preferably a methyl group. R a15 is preferably a hydrogen atom. R a16 is preferably a hydrogen atom or a hydroxy group. o1 is preferably an integer of 0 to 3, and more preferably 0 or 1.

[0121] Examples of the structural unit (a2-1) include those described in JP-A-2010-204646. The structural units derived from the monomers of formula (a2-1-1) to formula (a2-1-6) are examples. ) is preferred, and a structural unit represented by any one of the formulas (a2-1-1) to (a2-1-4) The structural unit represented by formula (a2-1-1) or formula (a2-1- The structural unit represented by 3) is more preferred. TIFF0007672459000087.tif50138

[0122] When the resin (A) contains the structural unit (a2-1), its content is determined based on the total amount of all structural units in the resin (A). It is usually 1 to 45 mol %, preferably 1 to 40 mol %, more preferably It is preferably 1 to 35 mol %, more preferably 2 to 20 mol %, and even more preferably The content is usually 2 to 10 mol %.

[0123] <Structural unit (a3)> The lactone ring contained in the structural unit (a3) ​​is a β-propiolactone ring, a γ-butyrolactone ring, or It may be a monocyclic ring such as a lactone ring or a δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring with another ring. Preferably, the ring is a γ-butyrolactone ring, an adamantane lactone ring, or a γ -Bridged ring containing a butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)) Examples include:

[0124] The structural unit (a3) ​​is preferably a structural unit represented by the formula (a3-1), the formula (a3-2), the formula (a3-3), or a structural unit represented by formula (a3-4). One of these may be contained alone, Two or more types may be contained. TIFF0007672459000088.tif46147 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6 are each independently -O- or -O-(CH2) k3 -CO-O -(k3 represents an integer of 1 to 7). L a7 -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -C OOL a9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates a bond to the carbonyl group. R a18 , R a19 and R a20 each independently represents a hydrogen atom or a methyl group. R a24 is an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Represents a gen 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 a group having 1 to 10 carbon atoms; 4 represents an aliphatic hydrocarbon group. p1 represents an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3. w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same as or different from each other.

[0125] R a21 , R a22 , R a23 and R a25 The aliphatic hydrocarbon group in group, propyl group, isopropyl group, butyl group, sec-butyl group and tert-butyl group Examples of alkyl groups include: R a24 The halogen atoms in the formula (I) include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. Children are mentioned. R a24The alkyl group in the formula (I) is a methyl group, an ethyl group, a propyl group, an isopropyl group, or the like. groups, butyl groups, sec-butyl groups, tert-butyl groups, pentyl groups, and hexyl groups. Preferably, an alkyl group having 1 to 4 carbon atoms is used, more preferably a methyl group or is an ethyl group. R a24 Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a phenyl group, and the like. perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluoro perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoro Fluoropentyl group, perfluorohexyl group, trichloromethyl group, tribromomethyl group group, triiodomethyl group, and the like. L a8 and L a9 The alkanediyl group in the formula (I) is a methylene group, an ethylene group, a propane group, or -1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, penta hexane-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.

[0126] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably is -O- or *-O-(CH2) k3 In -CO-O-, k3 is any one of 1 to 4 groups which are integers, more preferably -O- and *-O-CH2-CO-O-, even more preferably The most common is an oxygen atom. R a18 ~R a21is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group or a methyl group is. p1, q1, and r1 each independently represent an integer of preferably 0 to 2, More preferably, it is 0 or 1.

[0127] In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. group, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom. It is a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-OL a8 -CO-O-, more preferably -O -, -O-CH2-CO-O- or -O-C2H4-CO-O-. w1 is preferably an integer of 0 to 2, and more preferably 0 or 1. In particular, the formula (a3-4) is preferably the formula (a3-4)'. TIFF0007672459000089.tif4928(in the formula, R a24 , L a7 has the same meaning as above.)

[0128] The structural unit (a3) ​​may be a monomer described in JP-A-2010-204646. , the monomers described in JP-A-2000-122294, and JP-A-2012-41274 Examples of the structural unit (a3) ​​include structural units derived from the monomers described in the above publication. , 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 (a3-4-1 2), and in the structural unit, the structural unit represented by formula (a3-1) to formula (a3-2) R in a3-4) a18 , R a19 , R a20 and R a24 The corresponding methyl group is placed on the hydrogen atom. Substituted structural units are preferred.

[0129] TIFF0007672459000090.tif115164

[0130] When the resin (A) contains the structural unit (a3), the total content of the structural unit (a3) ​​is the total content of all structural units of the resin (A). It is usually 5 to 70 mol %, preferably 10 to 65 mol %, more preferably The content is preferably 10 to 60 mol %. In addition, the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3) or the structural unit (a3-4) The content of the units (a3-4) is 5 to 60 moles per total structural units of the resin (A). % by mole, more preferably 5 to 50 mol %, and even more preferably 10 to 50 mol %.

[0131] <Structural unit (a4)> Examples of the structural unit (a4) include the following structural units. TIFF0007672459000091.tif3066[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having 1 to 24 carbon atoms and containing a fluorine atom, The —CH2— contained in the group may be replaced with —O— or —CO.] R 42 The saturated hydrocarbon group represented by the formula (I) is a chain hydrocarbon group and a monocyclic or polycyclic alicyclic hydrocarbon group. groups, and groups formed by combining these groups.

[0132] Examples of the chain hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, Hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, hexa Examples include decyl, heptadecyl, and octadecyl groups. The hydrogen group includes a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and cycloalkyl groups such as methyl group; decahydronaphthyl group, adamantyl group, norbornyl group and polycyclic and alicyclic hydrocarbon groups such as the following groups (* represents a bond): TIFF0007672459000092.tif11159The group formed by the combination may include one or more alkyl groups or one or more alkanedi groups. and groups formed by combining an alkyl group with one or more alicyclic hydrocarbon groups. -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, -alkanediyl group-alicyclic hydrocarbon group Examples include a candiyl group-alicyclic hydrocarbon group-alkyl group.

[0133] The structural unit (a4) includes the formula (a4-0), the formula (a4-1), the formula (a4-2), the formula (a4-3), the formula (a4-4), the formula (a4-5), the formula (a4-6), the formula (a4-7), the formula (a4-8), the formula (a4-9), the formula (a4-10), the formula (a4-11), the formula (a4-12), the formula (a4-13), the formula ( a4-3) and a structure represented by at least one selected from the group consisting of formula (a4-4) Units include: TIFF0007672459000093.tif4552[In formula (a4-0), R 5 represents a hydrogen atom or a methyl group. L 4a represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 4 carbon atoms. L 3a is a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluoroalkanediyl group having 3 to 12 carbon atoms. represents a fluorocycloalkanediyl group. R 6 represents a hydrogen atom or a fluorine atom.

[0134] L 4a The divalent saturated aliphatic hydrocarbon group in linear alkanediyl groups such as pan-1,3-diyl and butane-1,4-diyl groups, ethoxylated propane-1,1-diyl group, propane-1,2-diyl group, butane-1,3-diyl group, 2- Branched groups such as methylpropane-1,3-diyl and 2-methylpropane-1,2-diyl groups alkanediyl groups. L 3a The perfluoroalkanediyl group in Fluoroethylene group, perfluoropropane-1,1-diyl group, perfluoropropane -1,3-diyl group, perfluoropropane-1,2-diyl group, perfluoropropane -2,2-diyl group, perfluorobutane-1,4-diyl group, perfluorobutane-2 ,2-diyl group, perfluorobutane-1,2-diyl group, perfluoropentane-1, 5-diyl group, perfluoropentane-2,2-diyl group, perfluoropentane-3, 3-diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2, 2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1, 7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3, 4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1, 8-diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3, 3-diyl group, perfluorooctane-4,4-diyl group, and the like. L 3a The perfluorocycloalkanediyl group in perfluorocyclopentanediyl group, perfluorocycloheptanediyl group yl group, perfluoroadamantanediyl group, and the like.

[0135] L 4a is preferably a single bond, a methylene group or an ethylene group, more preferably a single bond, bond, a methylene group. L 3a is preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, more preferably or a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0136] The structural unit (a4-0) may be the following structural unit or a structural unit ( a4-0) in R 5 The structural unit in which the methyl group corresponding to can be. TIFF0007672459000094.tif95166

[0137] TIFF0007672459000095.tif4466[In formula (a4-1), R a41 represents a hydrogen atom or a methyl group. R a42 represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, The -CH2- contained in the hydrocarbon group may be replaced with -O- or -CO-. A a41 represents an alkanediyl group having 1 to 6 carbon atoms which may have a substituent, or a group represented by the formula (ag 1), where A a41 and R a42 At least one of the The group has a halogen atom (preferably a fluorine atom). TIFF0007672459000096.tif1384 [In formula (a-g1), s represents 0 or 1. Aa42 and A a44 are each independently a divalent group having 1 to 5 carbon atoms which may have a substituent. Represents a saturated hydrocarbon group. A a43 is a single bond or a divalent aliphatic hydrocarbon having 1 to 5 carbon atoms which may have a substituent. Represents a group. X a41 and X a42 are each independently -O-, -CO-, -CO-O- or -O-CO - represents. However, A a42 , A a43 , A a44 , X a41 and X a42 The total number of carbon atoms is 7 or less. * is a bond, and the * on the right is -O-CO-R a42 It is a combination with .]

[0138] R a42 The saturated hydrocarbon group in the formula (I) is a chain saturated hydrocarbon group or a monocyclic or polycyclic alicyclic group. saturated hydrocarbon groups of the formula: do. Examples of the chain saturated hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, heptyl group, Examples include a decyl group, a heptadecyl group, and an octadecyl group. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, ... Cycloalkyl groups such as cycloheptyl and cyclooctyl; decahydronaphthyl, adducts, etc. Polycyclic alicyclic saturated groups such as manthyl group, norbornyl group, and the following groups (* represents a bond): and alkyl hydrocarbon groups. TIFF0007672459000097.tif11159The group formed by the combination may include one or more alkyl groups or one or more alkanedi groups. and groups formed by combining an alkyl group with one or more alicyclic saturated hydrocarbon groups. -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkanediyl group Examples include an -alkanediyl group, -alicyclic saturated hydrocarbon group, and -alkyl group.

[0139] R a42 The substituents which may be contained in the group (a-g3) include a halogen atom and a group represented by the formula (a-g3): The halogen atom may be at least one selected from the group consisting of fluorine, methyl ... Examples of the fluorine atom include a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferred. TIFF0007672459000098.tif965[In formula (a-g3), X a43 represents an oxygen atom, a carbonyl group, *-O-CO- or *-CO-O- (* represents R a42 (represents a bond with ). A a45 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. . * represents a bond.] However, R a42 -X a43 -A a45 In R a42 If A does not have a halogen atom, a4 5 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms and at least one halogen atom .

[0140] A a45 The aliphatic hydrocarbon group in group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, penta Alkyl groups such as decyl, hexadecyl, heptadecyl, and octadecyl groups; Monocyclic groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups alicyclic hydrocarbon groups; and decahydronaphthyl groups, adamantyl groups, norbornyl groups, and and polycyclic and alicyclic hydrocarbon groups such as the following groups (* represents a bond): TIFF0007672459000099.tif11159The group formed by the combination may include one or more alkyl groups or one or more alkanedi groups. and groups formed by combining an alkyl group with one or more alicyclic hydrocarbon groups. -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, -alkanediyl group-alicyclic hydrocarbon group Examples include a candiyl group-alicyclic hydrocarbon group-alkyl group.

[0141] R a42 is preferably an aliphatic hydrocarbon group which may have a halogen atom, and / or an aliphatic hydrocarbon group having a group represented by formula (a-g3) More preferable. R a42 When is an aliphatic hydrocarbon group having a halogen atom, it is preferable that It is preferably an aliphatic hydrocarbon group having a perfluoroalkyl group or a perfluoroalkyl group. and preferably a perfluoroalkyl group having 1 to 6 carbon atoms. and particularly preferably a perfluoroalkyl group having 1 to 3 carbon atoms. Examples of alkyl groups include perfluoromethyl groups, perfluoroethyl groups, and perfluoropropyl groups. perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, Examples include a fluoroheptyl group and a perfluorooctyl group. Examples of the alkyl group include a perfluorocyclohexyl group. R a42is an aliphatic hydrocarbon group having a group represented by formula (a-g3), -g3) and the number of carbon atoms contained in the group represented by R a42 The total number of carbon atoms is preferably 15 or less. When the group represented by formula (a-g3) is contained as a substituent, , the number is preferably one.

[0142] R a42 is an aliphatic hydrocarbon having a group represented by formula (a-g3), R a42 Yes, More preferred is a group represented by formula (a-g2). TIFF0007672459000100.tif879[In formula (a-g2), A a46 represents a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. Represents. X a44 represents *-O-CO- or *-CO-O- (* represents A a46 (represents a bond with ). A a47 represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. . However, A a46 , A a47 and X a44 The total number of carbon atoms in A is 18 or less. a46 and A a47 of At least one of them has at least one halogen atom. * indicates a bond to the carbonyl group.

[0143] A a46 The aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms, and more preferably 1 to 3 carbon atoms. A a47 The aliphatic hydrocarbon group preferably has 4 to 15 carbon atoms, more preferably 5 to 12 carbon atoms, A a47 is more preferably a cyclohexyl group or an adamantyl group.

[0144] A preferred structure of the group represented by formula (a-g2) is the following structure (* indicates a carbonyl group): (It is a combination with ). TIFF0007672459000101.tif14160

[0145] A a41 The alkanediyl group in the formula (I) includes a methylene group, an ethylene group, a propane-1, 3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 linear alkanediyl groups such as propane-1,2-diyl, butane-1,6-diyl; ,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4- and branched alkanediyl groups such as 2-methylbutane-1,4-diyl and 2-methylbutane-1,4-diyl. do. A a41 The substituents in the alkanediyl group include a hydroxy group and an alkanediyl group having 1 to 6 carbon atoms. Examples thereof include an alkoxy group. A a41 is preferably an alkanediyl group having 1 to 4 carbon atoms, more preferably It is preferably an alkanediyl group having 2 to 4 carbon atoms, and more preferably an ethylene group.

[0146] A in the group represented by formula (a-g1) a42 , A a43 and A a44 represents the divalent saturated hydrocarbon The element groups include linear or branched alkanediyl groups and monocyclic divalent alicyclic saturated hydrocarbon groups. and a divalent alicyclic saturated hydrocarbon group. Specifically, a methylene group, an ethylene group, a propane-1,3-diamine group, and the like can be mentioned. propane-1,2-diyl group, butane-1,4-diyl group, 1-methylpropane -1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1 , 2-diyl group, etc. A a42 , A a43 and A a44 The substituent of the divalent saturated hydrocarbon group represented by is a hydroxy group. and alkoxy groups having 1 to 6 carbon atoms. Preferably, s is 0.

[0147] In the group represented by formula (a-g2), X a42 is -O-, -CO-, -CO-O- or Examples of the -O-CO- group include the following groups: ** represents a bond, and ** is -O-CO-R a42 It is a combination of. TIFF0007672459000102.tif54162

[0148] The structural unit represented by formula (a4-1) includes the following structural units and R in the structural unit represented by formula (a4-1) a41 A methyl group corresponding to Examples of structural units that have been replaced include: TIFF0007672459000103.tif167144

[0149] TIFF0007672459000104.tif66134

[0150] The structural unit represented by formula (a4-1) is preferably a structural unit represented by formula (a4-2). I wish. TIFF0007672459000105.tif4366[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 —C H2- may be replaced by -O- or -CO-. R f6 represents a saturated hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom. However, L 44 and R f6 The maximum total carbon number is 21.]

[0151] L 44 The alkanediyl group having 1 to 6 carbon atoms is L 4a As an example, the alkanediyl group in Examples of the groups include the same groups as those mentioned above. R f6 The saturated hydrocarbon group of R a42 Examples of the groups include the same groups as those exemplified in L 44 The alkanediyl group having 1 to 6 carbon atoms is preferably an alkanediyl group having 2 to 4 carbon atoms. A methyl group is preferred, and an ethylene group is more preferred.

[0152] Examples of the structural unit represented by formula (a4-2) include those represented by formula (a4-1-1) to formula (a4 -1-11) are structural units represented by the structural unit (a4-2). R f5 The structural unit in which the corresponding methyl group is replaced by a hydrogen atom is also represented by formula (a4-2). It is one of the structural units.

[0153] Examples of the structural unit (a4) include a structural unit represented by formula (a4-3). TIFF0007672459000106.tif5670[In formula (a4-3), R f7 represents a hydrogen atom or a methyl group. L 5 represents an alkanediyl group having 1 to 6 carbon atoms. A f13 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms which may have a fluorine atom. vinegar. X f12represents *-O-CO- or *-CO-O- (* represents A f13 ) . A f14 represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may contain a fluorine atom. However, A f13 and A f14 At least one of L has a fluorine atom, 5 , A f13 and A f14 The total number of carbon atoms in a molecule is limited to 20.

[0154] L 5 The alkanediyl group in 4 Divalent saturated hydrocarbon radicals in alkane Examples include the same groups as those exemplified for the diyl group. A f13 The divalent saturated hydrocarbon group optionally having a fluorine atom in or a divalent aliphatic saturated hydrocarbon group which may have a fluorine atom and a It is a divalent alicyclic saturated hydrocarbon group which may be present, and more preferably a perfluoroalkanedi group. It is a yl group. The divalent aliphatic hydrocarbon group which may have a fluorine atom includes a methylene group, an ethylene group, alkanediyl groups such as an alkanediyl group, a propanediyl group, a butanediyl group, and a pentanediyl group; Difluoromethylene group, perfluoroethylene group, perfluoropropanediyl group, per Perfluoroalkanediyl groups such as fluorobutanediyl and perfluoropentanediyl groups Examples of the aryl group include aryl groups. The divalent alicyclic hydrocarbon group which may have a fluorine atom may be either monocyclic or polycyclic. Examples of the monocyclic group include a cyclohexanediyl group and a perfluorocyclohexyl group. Examples of the polycyclic group include an adamantanediyl group, a norbornanediyl group, and the like. diyl group, perfluoroadamantanediyl group, and the like. A f14 The saturated hydrocarbon group and the saturated hydrocarbon group which may have a fluorine atom are R a42 in The same groups as those exemplified above can be mentioned. Among them, trifluoromethyl group, difluoromethyl group, ethyl 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 perfluorohexyl group. Fluorinated alkyl groups such as fluorooctyl groups, cyclopropylmethyl groups, cyclopropyl groups , cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group xyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantine A methyl group is preferred.

[0155] In formula (a4-3), L 5 is preferably an ethylene group. A f13 The divalent saturated hydrocarbon group is a divalent chain hydrocarbon group having 1 to 6 carbon atoms and a divalent chain hydrocarbon group having 3 carbon atoms. A group containing a divalent alicyclic hydrocarbon group having 2 to 12 carbon atoms is preferred, and a divalent chain hydrocarbon group having 2 to 3 carbon atoms is preferred. The basic group is more preferred. A f14 The saturated hydrocarbon group is a chain hydrocarbon group having 3 to 12 carbon atoms and an aliphatic hydrocarbon group having 3 to 12 carbon atoms. Groups containing cyclic hydrocarbon groups are preferred, and chain hydrocarbon groups having 3 to 10 carbon atoms and groups having 3 to 1 carbon atoms are also preferred. A group containing an alicyclic hydrocarbon group of A is more preferred. f14 is preferably carbon It is a group containing an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably, cyclopropylmethyl groups, cyclopentyl groups, cyclohexyl groups, norbornyl groups, and adamantyl groups.

[0156] Examples of the structural unit represented by formula (a4-3) include those represented by formula (a4-1'-1) to formula (a 4-1'-11) are structural units represented by the following formulas. KerR f7 The structural unit in which the corresponding methyl group is replaced by a hydrogen atom is also represented by formula (a4-3). It is one of the structural units that can be mentioned.

[0157] The structural unit (a4) also includes a structural unit represented by formula (a4-4). TIFF0007672459000107.tif4466[In formula (a4-4), R f21 represents a hydrogen atom or a methyl group. A f21 is -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -or-(CH2) j4 - CO-O-(CH2) j5 - represents. j1 to j5 each independently represent an integer of 1 to 6. R f22 represents a saturated hydrocarbon group having 1 to 10 carbon atoms and containing a fluorine atom.]

[0158] R f22 The saturated hydrocarbon group of R a42 The saturated hydrocarbon group may be the same as the saturated hydrocarbon group represented by the following formula: R f22represents an alkyl group having 1 to 10 carbon atoms and a fluorine atom, or a carbon atom having a fluorine atom An alicyclic hydrocarbon group having 1 to 10 carbon atoms is preferred, and an alkyl group having 1 to 10 carbon atoms and a fluorine atom is preferred. A fluorine atom-containing alkyl group having 1 to 6 carbon atoms is more preferred.

[0159] In formula (a4-4), A f21 As -(CH2) j1 - is preferred, and ethylene A group or a methylene group is more preferred, and a methylene group is even more preferred.

[0160] Examples of the structural unit represented by formula (a4-4) include the following structural units and In the structural unit represented by R in the structural unit (a4-4) f21 The methyl group corresponding to Examples of structural units include those in which hydrogen atoms are replaced. TIFF0007672459000108.tif86160

[0161] When the resin (A) has the structural unit (a4), its content is determined based on the total structural units of the resin (A). The ratio is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and more preferably 3 to 10 mol % is more preferred.

[0162] <Structural unit (a5)> The non-leaving hydrocarbon group contained in the structural unit (a5) may be a straight-chain, branched or cyclic hydrocarbon group. Among these, the structural unit (a5) is preferably a group having an alicyclic hydrocarbon group. The group is preferred. Examples of the structural unit (a5) include a structural unit represented by the formula (a5-1): . TIFF0007672459000109.tif3971[In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and the water contained in the alicyclic hydrocarbon group The atom 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, The —CH2— contained in the formula may be replaced with —O— or —CO—.

[0163] R 52 The alicyclic hydrocarbon group in may be either a monocyclic or polycyclic group. Examples of the alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclopentyl group. Examples of the polycyclic alicyclic hydrocarbon group include: , an adamantyl group, and a norbornyl group. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, and an isopropyl group. Propyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group Examples of alkyl groups include an octyl group and a 2-ethylhexyl group. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. do. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably Examples thereof include an adamantyl group, a norbornyl group, and a cyclohexyl group. L 55 The divalent saturated hydrocarbon group in the above is a divalent chain saturated hydrocarbon group and a divalent fatty acid group. Examples include cyclic saturated hydrocarbon groups, and preferably divalent chain saturated hydrocarbon groups. Examples of the divalent chain saturated hydrocarbon group include a methylene group, an ethylene group, and a propanediol group. alkanediyl groups such as butanediyl, pentanediyl, and the like. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of saturated hydrocarbon groups include cyclopentanediyl and cyclohexanediyl groups. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include an adatom group. Examples include a mantanediyl group and a norbornanediyl group.

[0164] L 55 The -CH2- contained in the divalent saturated hydrocarbon group represented by is replaced by -O- or -CO-. Examples of the substituted groups include groups represented by formulae (L1-1) to (L1-4). In the following formula, * and ** each represent a bond, and * represents a bond to an oxygen atom. TIFF0007672459000110.tif18165 formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 represents a bond with . ). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, L x1 and L x2 The total number of carbon atoms is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, L x3 and L x4 The total number of carbon atoms is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and Lx7 are each independently a single bond or a divalent aliphatic saturated carbon atom having 1 to 14 carbon atoms. Represents a hydrogen group. However, L x5 , L x6 and L x7 The total number of carbon atoms is 15 or less. In formula (L1-4), L x8 and L x9 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, L x8 , L x9 and W x1 The total number of carbon atoms is 15 or less.

[0165] L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably It is a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably Preferably, it is a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably It is a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably Preferably, it is 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 x8is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably Preferably, it is 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 Preferably, it is 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.

[0166] Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF0007672459000111.tif53135

[0167] Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF0007672459000112.tif23130

[0168] Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF0007672459000113.tif15145

[0169] Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF0007672459000114.tif26115

[0170] L 55 is preferably a single bond or a group represented by formula (L1-1).

[0171] The structural unit (a5-1) includes the structural units shown below and the structural units ( R in a5-1) 51 The structural unit in which the methyl group corresponding to can be. TIFF0007672459000115.tif75150 TIFF0007672459000116.tif36152 When the resin (A) has the structural unit (a5), its content is determined based on the total structural units of the resin (A). The ratio is preferably 1 to 30 mol %, more preferably 2 to 20 mol %, and more preferably 3 to 15 mol % is more preferred.

[0172] <Structural unit (II)> The resin (A) further contains a structural unit that decomposes upon exposure to generate an acid (hereinafter, “structural unit”). The structural unit (II) may include, specifically, Examples of structural units include those described in JP-A-2016-79235, which have a sulfonate group or a hydroxyl group in the side chain. or a structural unit having a carboxylate group and an organic cation, or a structural unit having a sulfonio group on a side chain It is preferable that the structural unit has an organic anion.

[0173] The structural unit having a sulfonate group or a carboxylate group in the side chain is represented by the formula (II-2 -A') is preferably a structural unit represented by the formula: TIFF0007672459000117.tif36104[In formula (II-2-A'), X III3 represents a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the saturated hydrocarbon group -CH2- may be replaced by -O-, -S- or -CO-, and the saturated hydrocarbon The hydrogen atoms contained in the group are replaced by halogen atoms, alkyl groups having 1 to 10 carbon atoms which may have halogen atoms. 6 may be substituted with an alkyl group or a hydroxy group. A x1 represents an alkanediyl group having 1 to 8 carbon atoms, and the hydrogen atoms contained in the alkanediyl group The atom may be substituted with a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. . RA - represents a sulfonate group or a carboxylate group. R III3 is a hydrogen atom, a halogen atom, or a group having 1 to 6 carbon atoms which may have a halogen atom represents an alkyl group represented by the formula: ZA + represents an organic cation.

[0174] R III3 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Atoms and the like can be mentioned. R III3 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom and is represented by the formula: , R a8 The same as the alkyl group having 1 to 6 carbon atoms which may have a halogen atom and which is represented by Examples include: A x1 Examples of the alkanediyl group having 1 to 8 carbon atoms represented by the formula (I) include a methylene group, an ethylene group, Propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group , hexane-1,6-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group yl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc. . A x1 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms which may be substituted include trifluoroalkyl groups. perfluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group Examples thereof include a perfluoropentyl group, a perfluorohexyl group, and the like. X III3 The divalent saturated hydrocarbon group having 1 to 18 carbon atoms represented by the formula (I) is a straight-chain or branched alkyl group. and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups. It may be a combination. Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1, 2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1 ,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane- 1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group linear alkanediyl groups such as decane-1,12-diyl; butane-1,3-diyl; 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentaerythritol Branched alkanediyl groups such as 2-methylbutane-1,4-diyl group, 2-methylbutane-1,4-diyl group cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohetane-1,3-diyl group, Cycloalkanediyl groups such as cyclohexan-1,4-diyl group and cyclooctane-1,5-diyl group norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane Divalent polycyclic alicyclic saturated carbons such as benzophenone-1,5-diyl and adamantane-2,6-diyl groups Examples thereof include a hydrogen hydride group. -CH2- in saturated hydrocarbon groups is replaced with -O-, -S- or -CO- Examples of such groups include divalent groups represented by formulae (X1) to (X53). The -CH2- contained in the saturated hydrocarbon group is replaced with -O-, -S- or -CO-. The number of carbon atoms in each of the preceding groups is 17 or less. In the following formula, * and ** represent binding sites. * is A x1 Represents a bond with . TIFF0007672459000118.tif145161

[0175] 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.

[0176] ZA in formula (II-2-A') + is the cation Z in salt (I) + Similar things are listed It can be obtained.

[0177] The structural unit represented by formula (II-2-A') is a structural unit represented by formula (II-2-A) It is preferable that: TIFF0007672459000119.tif38108 [In formula (II-2-A), R III3 , X III3 and ZA + has the same meaning as above. z2A represents an integer of 0 to 6. R III2 and R III4 are each independently a hydrogen atom, a fluorine atom, or a phenyl group having 1 to 6 carbon atoms. When z is 2 or more, multiple R III2 and R III4 are identical to each other may be the same or may be different. Q a and Q b are each independently a fluorine atom or a perfluoroalkane having 1 to 6 carbon atoms. represents a alkyl group.] R III2 , R III4 , Q a and Q b The perfluoroalkyl group having 1 to 6 carbon atoms is represented by the formula: For details, please refer to the Q b1 The perfluoroalkyl group having 1 to 6 carbon atoms is the same as the perfluoroalkyl group represented by the formula: can be.

[0178] The structural unit represented by formula (II-2-A) is a structural unit represented by formula (II-2-A-1). It is preferable that the position is . TIFF0007672459000120.tif5578 [In formula (II-2-A-1), R III2 , R III3 , R III4 , Q a , Q b and ZA + has the same meaning as above. R III5 represents a saturated hydrocarbon group having 1 to 12 carbon atoms. z2A1 represents an integer of 0 to 6. X I2 represents a divalent saturated hydrocarbon group having 1 to 11 carbon atoms, and -CH2- may be replaced by -O-, -S- or -CO-, and the saturated hydrocarbon A hydrogen atom contained in the group may be substituted with a halogen atom or a hydroxy group. R III5 Examples of the saturated hydrocarbon group having 1 to 12 carbon atoms represented by the formula include a methyl group, an ethyl group, a propane group, and a propyl group. propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl methyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl and dodecyl groups. Examples include straight-chain or branched alkyl groups such as a decyl group. X I2 As the divalent saturated hydrocarbon group represented by X III3Divalent saturated hydrocarbons represented by The same groups as those mentioned above can be mentioned.

[0179] The structural unit represented by formula (II-2-A-1) is preferably a structural unit represented by formula (II-2-A-2). More preferred are structural units in which TIFF0007672459000121.tif5288 [In formula (II-2-A-2), R III3 , R III5 and ZA + has the same meaning as above. m and n each independently represent 1 or 2.

[0180] Examples of the structural unit represented by formula (II-2-A') include the following structural units and the International Examples include the structural units described in Publication No. 2012 / 050015. + is an organic cation Represents. TIFF0007672459000122.tif79163

[0181] TIFF0007672459000123.tif82153

[0182] The structural unit having a sulfonio group and an organic anion in the side chain is represented by formula (II-1-1): It is preferable that the structural unit is a structural unit that can be formed by the above-mentioned method. TIFF0007672459000124.tif3791 [In formula (II-1-1), A II1 represents a single bond or a divalent linking group. R II1 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R II2 and R II3 each independently represents a hydrocarbon group having 1 to 18 carbon atoms; R II2 Reach BiR II3 may be bonded to each other to form a ring together with the sulfur atom to which they are attached. R II4is a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. represents an alkyl group. A - represents an organic anion. R II1 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by the formula (I) include a phenylene group and and naphthylene groups. R II2 and R II3 Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and aromatic hydrocarbon groups and groups formed by combining these groups. R II4 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Atoms and the like can be mentioned. R II4 The alkyl group having 1 to 6 carbon atoms which may have a halogen atom and is represented by the formula: , R a8 The same as the alkyl group having 1 to 6 carbon atoms which may have a halogen atom and which is represented by Examples include: A II1 Examples of the divalent linking group represented by the formula (I) include a divalent saturated hydrocarbon group having 1 to 18 carbon atoms. The -CH2- contained in the divalent saturated hydrocarbon group may be -O-, -S- or Specifically, X may be replaced with -CO-. III3 2 of carbon atoms 1 to 18 represented by The examples of the saturated hydrocarbon groups include the same as those of the 4-valent saturated hydrocarbon groups.

[0183] The structural unit containing a cation in formula (II-1-1) includes structural units represented by the following formula: Examples include: TIFF0007672459000125.tif80143

[0184] TIFF0007672459000126.tif99139

[0185] A - Examples of the organic anion represented by the formula include a sulfonate anion, a sulfonylimide anion, and Examples include sulfonylmethide anions, carboxylic acid anions, and the like. - is expressed as The organic anion is preferably a sulfonate anion. More preferably, it is an anion contained in the salt represented by formula (B1).

[0186] A - Examples of the sulfonylimide anion represented by the formula (I) include the following. TIFF0007672459000127.tif43135

[0187] Examples of sulfonylmethide anions include the following: TIFF0007672459000128.tif29123

[0188] Examples of carboxylate anions include the following: TIFF0007672459000129.tif51153

[0189] Examples of the structural unit represented by formula (II-1-1) include the structural units represented by the following formula: can be done. TIFF0007672459000130.tif161141

[0190] When the structural unit (II) is contained in the resin (A), the content of the structural unit (II) is It is preferably 1 to 20 mol %, more preferably 2 to 30 mol %, based on the total structural units of the fat (A). It is 15 mol %, and more preferably 3 to 10 mol %.

[0191] The resin (A) may have structural units other than the above-mentioned structural units. The moieties include structural units known in the art.

[0192] The resin (A) is preferably a resin comprising the structural unit (a1) and the structural unit (s), i.e., That is, it is a copolymer of the monomer (a1) and the monomer (s). The structural unit (a1) is preferably a structural unit (a1-0), a structural unit (a1-1), a structural unit (a1-2), a structural unit (a1-3), a structural unit (a1-4), a structural unit (a1-5), a structural unit (a1-6), a structural unit (a1-7), a structural unit (a1-8), a structural unit (a1-9), a structural unit (a1-1 ... Unit (a1-2) (preferably the structure having a cyclohexyl group and a cyclopentyl group) unit) and structural unit (a1-4), and more preferably Preferably, at least two types are used, and more preferably, the structural unit (a1-1) and the structural unit (a1-2) are used. At least two selected from the group consisting of (a1-2). The structural unit (s) is preferably selected from the group consisting of the structural unit (a2) and the structural unit (a3): The structural unit (a2) is preferably at least one selected from the structural unit (a2-1). Or the structural unit (a2-A), more preferably the structural unit (a2-A). The position (a3) ​​is preferably a structural unit represented by formula (a3-1), a structural unit represented by formula (a3-2), and at least one structural unit selected from the group consisting of structural units represented by formula (a3-4): It is a seed. The structural units constituting the resin (A) may be used singly or in combination of two or more. Instead, monomers that lead to these structural units are used in known polymerization methods (for example, radical polymerization methods). The content of each structural unit contained in the resin (A) can be determined by the following procedure. It can be adjusted by the amount of monomer used. The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more). 00 or more, more preferably 3,000 or more), 50,000 or less (more preferably 30 In this specification, the weight average molecular weight is 1,000 or less, and more preferably 15,000 or less. The molecular weight is determined by gel permeation chromatography under the conditions described in the examples. is.

[0193] <Resins other than Resin (A)> The resist composition of the present invention may further contain a resin other than the resin (A). Examples of resins other than the resin (A) include those containing the structural unit (a4) or the structural unit (a5). Examples of the resin include a resin having the above structure (hereinafter, sometimes referred to as resin (X)). As the resin (X), a resin containing the structural unit (a4) is particularly preferred. A resin containing a structural unit having a fluorine atom is preferred. In resin (X), the content of structural unit (a4) is the sum of all structural units in resin (X). It is preferably 30 mol % or more, more preferably 40 mol % or more. It is more preferable that the content is 45 mol % or more. Examples of structural units that the resin (X) may further have include the structural unit (a1), the structural unit (a2), structural unit (a3), and structural units derived from other known monomers. Among these, the resin (X) is preferably composed only of the structural unit (a4) and / or the structural unit (a5). It is preferably a resin. The structural units constituting the resin (X) may be used alone or in combination of two or more. Using monomers that derive these structural units, a known polymerization method (e.g., radical polymerization method) can be used. The content of each structural unit in the resin (X) can be determined by the following procedure. It can be adjusted by the amount of monomer used. The weight average molecular weight of each resin (X) is preferably 6,000 or more (more preferably 6,000 or more). Preferably 7,000 or more), 80,000 or less (more preferably 60,000 or less) The weight average molecular weight of the resin (X) can be measured by the same method as in the case of the resin (A).

[0194] When the resist composition of the present invention contains resin (X), the content of resin (X) is 100% by weight of resin (A). The amount is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, based on the total mass of the hydroxybenzoates. The amount is more preferably 1 to 40 parts by mass, particularly preferably 1 to 30 parts by mass, and particularly preferably 1 to 40 parts by mass. The amount is preferably 1 to 8 parts by mass.

[0195] The content of resin (A) in the resist composition is 8% by weight based on the solid content of the resist composition. It is preferably 0% by mass or more and 99% by mass or less, and more preferably 90% by mass or more and 99% by mass or less. In addition, when a resin other than the resin (A) is contained, the resin (A) and the resin other than the resin (A) are preferably mixed. The total content of the resin is 80% by mass or more and 99% by mass or less of the solid content of the resist composition. The content is preferably 90% by mass or more and more preferably 99% by mass or less. The solid content of the product and the resin content relative to it are measured by liquid chromatography or gas chromatography. It can be measured by known analytical means such as graphy.

[0196] <Solvent (E)> The content of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less. It is preferably 92% by mass or more and 99% by mass or less, and more preferably 94% by mass or more. The content of the solvent (E) is 99% by mass or less. The content of the solvent (E) is measured by, for example, liquid chromatography or gas chromatography. It can be measured by known analytical means such as chromatography. The solvent (E) may be ethyl cellosolve acetate, methyl cellosolve acetate, or Glycol ether esters such as propylene glycol monomethyl ether acetate ; Glycol ethers such as propylene glycol monomethyl ether; Ethyl lactate, acetic acid esters such as butyl acetate, amyl acetate and ethyl pyruvate; acetone, methyl isobutyl esters; ketones such as cyclohexanone, 2-heptanone, and cyclohexanone; γ-butyrolactone; cyclic esters; etc. One type of solvent (E) may be used alone, Two or more types may be used.

[0197] <Quencher (C)> The quencher (C) is a basic nitrogen-containing organic compound and an acid generated from the acid generator (B). The quencher (C) content is The content is preferably about 0.01 to 5 mass % based on the solid content of the resist composition. Examples of basic nitrogen-containing organic compounds include amines and ammonium salts. The amines include aliphatic amines and aromatic amines. The aliphatic amines include primary amines, Amines include secondary amines and tertiary amines.

[0198] Amines include 1-naphthylamine, 2-naphthylamine, aniline, and diisopropylamine. aniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline Phosphorus, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine , octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, Dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine amine, triethylamine, trimethylamine, tripropylamine, tributylamine, Tripentylamine, trihexylamine, triheptylamine, trioctylamine, Trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine , methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, Methyldioctylamine, Methyldinonylamine, Methyldidecylamine, Ethyldibutylamine diamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine , ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexane xylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropylamine Propanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine amine, 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'-dipyridyl sulfide, 4,4'-dipyridyl disulfide amine, 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine, etc. Among them, preferred are aromatic amines such as diisopropylaniline, and more preferred are aromatic amines such as diisopropylaniline. Examples include 2,6-diisopropylaniline.

[0199] Ammonium salts include tetramethylammonium hydroxide, tetraisopropyl Lithium ammonium hydroxide, tetrabutylammonium hydroxide, tetrahexyl ammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethyl ammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, choline, and the like can be mentioned. and the like.

[0200] The acidity of the salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is indicated by the acid dissociation constant (pKa). An acid with a lower acidity than the acid generated from the acid generator (B) The salt that generates is a salt with an acid dissociation constant of the acid generated from the salt usually -3 < pKa, preferably is a salt of -1 < pKa < 7, and more preferably a salt of 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, may be referred to as " "weak acid intramolecular salt (D)"), and salts described in JP-A-2012-229206 , JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-3 9502, and JP-A-2011-191745. Preferably, the salt that generates an acid with a lower acidity than the acid generated from the acid generator (B) is a weak acid intramolecular salt (D). (B) Examples of the salt that generates an acid with a lower acidity than the acid generated from is preferably a weak acid intramolecular salt (D). TIFF0007672459000131.tif128168

[0201] Examples of the weak acid intramolecular salt (D) include the following salts. TIFF0007672459000132.tif88134

[0202] When the resist composition contains a quencher (C), the content of the quencher (C) is The amount of the hydroxybenzoates is usually from 0.01 to 5 mass %, preferably from 0.01 to 5 mass %, based on the solid content of the resist composition. It is 3% by mass.

[0203] <Other ingredients> The resist composition of the present invention may contain components other than the above-mentioned components (hereinafter referred to as "other components") as needed. It may contain other ingredients (F). The resist composition may contain additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, etc. Agents, dyes, etc. can be used.

[0204] <Preparation of Resist Composition> The resist composition of the present invention comprises a salt (I) and a resin (A), and, if necessary, Acid generator (B), resin other than resin (A), solvent (E), quencher (C) and other The mixture can be prepared by mixing the other components (F) in any order. The temperature during mixing ranges from 10 to 40°C, depending on the type of resin, etc. An appropriate temperature can be selected depending on the solubility of the oil or the like in the solvent (E). Depending on the mixing temperature, an appropriate time can be selected from the range of 0.5 to 24 hours. The mixing means is not particularly limited, and stirring and mixing or the like can be used. After mixing the components, filter the mixture using a filter with a pore size of approximately 0.003 to 0.2 μm. It is preferable that

[0205] <Method for producing a resist pattern> The method for producing a resist pattern of the present invention comprises the steps of: (1) applying the resist composition of the present invention onto a substrate; (2) drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) A step of developing the composition layer after heating is included. To apply the resist composition to the substrate, a commonly used device such as a spin coater is used. The substrate can be an inorganic substrate such as a silicon wafer. Before applying the resist composition, the substrate may be cleaned, and an anti-reflection film or the like may be formed on the substrate. It may be possible. The composition after coating is dried to remove the solvent and form a composition layer. For example, the solvent can be evaporated using a heating device such as a hot plate (prebaking). The heating temperature is 50 to 200°C. The heating time is preferably 10 to 180 seconds. The pressure during this process is 1 to 1.0 x 10 5 It is preferable that the pressure is about Pa. The resulting composition layer is usually exposed using an exposure machine. The exposure light source may be a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm) Laser light emitted from a solid-state laser light source (YAG or semiconductor laser, etc.) Those that convert wavelength and emit harmonic laser light in the far ultraviolet or vacuum ultraviolet range, electron beams, Various types of light sources can be used, such as those that irradiate ultraviolet light (EUV). In this case, the irradiation of these radiations is sometimes collectively called "exposure". The exposure is usually carried out through a mask corresponding to the desired pattern. In the case of lines, exposure may be performed by direct writing without using a mask. The composition layer after exposure is subjected to a heat treatment (or The heating temperature is usually about 50 to 200°C, preferably The temperature is usually around 70 to 150°C. The composition layer after heating is usually developed using a developing device and a developing solution. Examples of methods include the dip method, paddle method, spray method, and dynamic dispense method. The development temperature is preferably, for example, 5 to 60°C, and the development time is, for example, 5 The time is preferably 300 seconds or less. By selecting the type of developer as follows: Either a positive resist pattern or a negative resist pattern can be produced. When a positive resist pattern is produced from the resist composition of the present invention, a developer An alkaline developer is used. The alkaline developer is any of the various alkaline waters used in this field. Any solution is acceptable. For example, tetramethylammonium hydroxide or (2-hydroxy Examples include an aqueous solution of ethyl)trimethylammonium hydroxide (commonly known as choline). The alkaline developer may contain a surfactant. After development, the resist pattern is washed with ultrapure water, and then the water remaining on the substrate and pattern is removed. It is preferable to remove it. When a negative resist pattern is produced from the resist composition of the present invention, a developer A developer containing an organic solvent (hereinafter sometimes referred to as an "organic developer") is used. The organic solvents contained in organic developers include ketones such as 2-hexanone and 2-heptanone. Glycol ether solvents such as propylene glycol monomethyl ether acetate Ester solvents such as butyl acetate; propylene glycol monomethyl ether, etc. Glycol ether solvents; amide solvents such as N,N-dimethylacetamide; anisole and aromatic hydrocarbon solvents such as the above. In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, The content is more preferably 95% by mass or more and 100% by mass or less, and more preferably substantially only an organic solvent. More preferable. Among them, organic developers include developers containing butyl acetate and / or 2-heptanone. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass. Preferably, the content is 90% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less. It is more preferable that the mixture is qualitatively only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant. The water content may be less than 100%. During development, development is stopped by replacing the organic developer with a different type of solvent. Good too. After development, the resist pattern is preferably washed with a rinse solution. There are no particular limitations as long as the solvent does not dissolve the resist pattern, and solvents containing general organic solvents are also usable. A solvent can be used, preferably an alcohol solvent or an ester solvent. After cleaning, it is preferable to remove the rinse liquid remaining on the substrate and the pattern.

[0206] <Application> The resist composition of the present invention is a resist composition for exposure to KrF excimer laser, ArF excimer laser, Resist composition for exposure to ultraviolet laser, resist composition for exposure to electron beam (EB) or EU resist compositions for V exposure, particularly resist compositions for electron beam (EB) exposure or EUV exposure The composition is suitable as a resist composition for semiconductors and is useful for microfabrication of semiconductors. [Example]

[0207] The present invention will be explained in more detail with reference to examples. "%" and "parts" are by weight unless otherwise specified. The weight average molecular weight is a value determined by gel permeation chromatography. The analytical conditions for gel permeation chromatography are as follows: Column: TSKgel Multipore HXL-M x 3 + guard column (Tosoh Corporation) Eluent: tetrahydrofuran Flow rate: 1.0mL / min Detector: RI detector Column temperature: 40℃ Injection volume: 100μl Molecular weight standard: Standard polystyrene (Tosoh Corporation) The structure of the compound was determined by mass spectrometry (LC: Agilent 1100, MASS: Agilent The molecular ion peak was measured using a LC / MSD (manufactured by ent). In the examples, the value of this molecular ion peak is indicated by "MASS."

[0208] Example 1: Synthesis of salt represented by formula (I-1) TIFF0007672459000133.tif43165 13 parts of the salt represented by formula (I-1-a) and 20 parts of chloroform were mixed and heated at 23°C for 30 minutes. To the resulting mixed solution, 5.05 parts of the compound represented by formula (I-1-b) was added. The mixture was added and stirred at 50° C. for 2 hours. 4.99 parts of the compound to be added dropwise over 10 minutes, and the mixture was stirred at 50°C for 18 hours. The mixture was cooled to 23° C. To the resulting mixture, 70 parts of chloroform and 2 parts of a 5% aqueous oxalic acid solution were added. After adding 5 parts of the mixture and stirring at 23°C for 30 minutes, the organic layer was separated and extracted. 30 parts of ion-exchanged water was added to the layer, and the mixture was stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated seven times. The resulting organic layer was concentrated, and the concentrated residue was diluted with acetonitrile. 25 parts of tolyl and 220 parts of tert-butyl methyl ether were added, and the mixture was heated at 23°C for 30 minutes. After stirring, the supernatant was removed and the mixture was concentrated. 220 parts of n-heptane was added to the resulting concentrated residue. The mixture was stirred at 23°C for 30 minutes, and then filtered to obtain a compound represented by formula (I-1). 6.70 parts of salt were obtained. MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 325.0

[0209] Example 2: Synthesis of salt represented by formula (I-4) TIFF0007672459000134.tif37116 45 parts of the compound represented by formula (I-4-a) and 225 parts of tetrahydrofuran were mixed, After stirring at 23°C for 30 minutes, the mixture was cooled to -65°C. 2.7 mol / l n-butyllithium (Aldrich) 253.2 ml for 15 minutes The mixture was added dropwise over a period of 1 hour, and then stirred at −65° C. for 4 hours. After adding 225 parts of ion-exchanged water dropwise over 10 minutes, the temperature was raised to 23°C and 36 parts of ethyl acetate was added. 0 parts of the mixture was added and stirred at 23°C for 30 minutes, and then the organic layer was separated and extracted. 80 parts of ion-exchanged water was added to the layer, and the mixture was stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated three times. The resulting organic layer was concentrated, and the concentrated mixture was passed through a column ( Silica gel 60N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Ltd. Developing solvent: n -heptane / ethyl acetate = 1 / 1) to obtain a compound represented by formula (I-4-b). 28.44 parts of the compound of interest were obtained. TIFF0007672459000135.tif45164 13 parts of the salt represented by formula (I-1-a) and 20 parts of chloroform were mixed and heated at 23°C for 30 minutes. To the resulting mixed solution, 5.05 parts of the compound represented by formula (I-1-b) was added. The mixture was added and stirred at 50° C. for 2 hours. 5.70 parts of the compound to be added dropwise over 10 minutes, and the mixture was stirred at 50°C for 18 hours. The mixture was cooled to 23° C. To the resulting mixture, 70 parts of chloroform and 2 parts of a 5% aqueous oxalic acid solution were added. After adding 5 parts of the mixture and stirring at 23°C for 30 minutes, the organic layer was separated and extracted. 30 parts of ion-exchanged water was added to the layer, and the mixture was stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated five times. The resulting organic layer was concentrated, and the concentrated residue was diluted with acetonitrile. Add 3 parts of tolyl and 30 parts of tert-butyl methyl ether, and stir at 23°C for 30 minutes. After that, the supernatant was removed and the mixture was concentrated to obtain 4.28 parts of the salt represented by formula (I-4). obtained. MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 349.1

[0210] Example 3: Synthesis of salt represented by formula (I-15) 9.54 parts of the salt represented by formula (I-15-a) and 30 parts of chloroform were mixed and heated at 23°C. The mixture was stirred at room temperature for 30 minutes. To the resulting mixture, 2.30 g of the compound represented by formula (I-1-c) A mixed solution of 10 parts of acetic acid and 10 parts of chloroform was added, and the mixture was further stirred at 23°C for 8 hours. To the resulting mixture, 30 parts of ion-exchanged water was added and stirred at 23°C for 30 minutes, and then the liquid was separated to obtain an organic To the obtained organic layer, 20 parts of a 5% aqueous oxalic acid solution was added, and the mixture was stirred at 23° C. for 30 minutes. After stirring for 1 hour, the organic layer was separated and separated. 30 parts of ion-exchanged water was added to the obtained organic layer. After stirring at 23°C for 30 minutes, the organic layer was separated and washed with water five times. The obtained organic layer was concentrated, and the concentrated residue was diluted with tert-butyl methyl ether. After adding 30 parts of the mixture and stirring at 23°C for 30 minutes, the supernatant was removed and the mixture was concentrated. As a result, 8.48 parts of the salt represented by formula (I-15) was obtained. MASS(ESI(+)Spectrum):M + 263.1 MASS(ESI(-)Spectrum):M - 533.1

[0211] Example 4: Synthesis of salt represented by formula (I-91) TIFF0007672459000137.tif44163 12.23 parts of the salt represented by formula (I-91-a) and 20 parts of chloroform were mixed, and 23 The mixture was stirred at 0°C for 30 minutes. To the resulting mixture, 5.0 g of the compound represented by formula (I-1-b) was added. 5 parts of the hydroxybenzoate of the formula (I-1-c 4.99 parts of a compound represented by the formula (1) was added dropwise over 10 minutes, and the mixture was further stirred at 50°C for 18 hours. After that, the mixture was cooled to 23° C. To the resulting mixture, 70 parts of chloroform and 5% oxalic acid were added. 25 parts of an aqueous solution was added, and the mixture was stirred at 23°C for 30 minutes, after which the organic layer was separated and taken out. 30 parts of ion-exchanged water was added to the organic layer and stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated five times. The obtained organic layer was concentrated, and the concentrated residue was 50 parts of tert-butyl methyl ether was added, and the mixture was stirred at 23°C for 30 minutes. The liquid was removed and the residue was concentrated to obtain 4.89 parts of the salt represented by formula (I-91). MASS(ESI(+)Spectrum):M + 237.1 MASS(ESI(-)Spectrum):M - 325.0

[0212] Example 5: Synthesis of salt represented by formula (I-136) TIFF0007672459000138.tif42165 10.74 parts of the salt represented by formula (I-136-a) and 20 parts of chloroform were mixed, and 2 The mixture was stirred at 3° C. for 30 minutes. Compound 5 represented by formula (I-1-b) was added to the resulting mixture. 0.5 parts of methyl 2-hydroxybenzoate, and the mixture was further stirred at 50° C. for 2 hours. 4.99 parts of the compound represented by c) was added dropwise over 10 minutes, and the mixture was further stirred at 50°C for 18 hours. After stirring, the mixture was cooled to 23° C. To the resulting mixture, 70 parts of chloroform and 5% oxalate were added. 25 parts of an aqueous acid solution was added, and the mixture was stirred at 23°C for 30 minutes, after which the organic layer was separated and taken out. 30 parts of ion-exchanged water was added to the organic layer and stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated five times. The obtained organic layer was concentrated, and the concentrated residue was 50 parts of tert-butyl methyl ether was added, and the mixture was stirred at 23°C for 30 minutes. The filtrate was removed and the residue was concentrated to obtain 4.11 parts of the salt represented by the formula (I-136). MASS(ESI(+)Spectrum):M + 187.1 MASS(ESI(-)Spectrum):M - 325.0

[0213] Example 6: Synthesis of salt represented by formula (I-61) TIFF0007672459000139.tif39164 13.53 parts of the salt represented by formula (I-61-a) and 20 parts of chloroform were mixed, and 23 The mixture was stirred at 0°C for 30 minutes. To the resulting mixture, 5.0 g of the compound represented by formula (I-1-b) was added. 5 parts of the hydroxybenzoate of the formula (I-1-c 4.99 parts of a compound represented by the formula (1) was added dropwise over 10 minutes, and the mixture was further stirred at 50°C for 18 hours. After that, the mixture was cooled to 23° C. To the resulting mixture, 70 parts of chloroform and 5% oxalic acid were added. 25 parts of an aqueous solution was added, and the mixture was stirred at 23°C for 30 minutes, after which the organic layer was separated and taken out. 30 parts of ion-exchanged water was added to the organic layer and stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated five times. The obtained organic layer was concentrated, and the concentrated residue was 50 parts of tert-butyl methyl ether was added, and the mixture was stirred at 23°C for 30 minutes. The liquid was removed and the mixture was concentrated. 100 parts of n-heptane was added to the concentrated residue obtained, and the mixture was stirred at 23°C. After stirring for 30 minutes, the mixture was filtered to obtain 6.81 parts of the salt represented by formula (I-61). Ta. MASS(ESI(+)Spectrum):M + 281.1 MASS(ESI(-)Spectrum):M - 325.0

[0214] Example 7: Synthesis of salt represented by formula (I-76) TIFF0007672459000140.tif44158 14.60 parts of the salt represented by formula (I-76-a) and 20 parts of chloroform were mixed, and 23 The mixture was stirred at 0°C for 30 minutes. To the resulting mixture, 5.0 g of the compound represented by formula (I-1-b) was added. 5 parts of the hydroxybenzoate of the formula (I-1-c 4.99 parts of a compound represented by the formula (1) was added dropwise over 10 minutes, and the mixture was further stirred at 50°C for 18 hours. After that, the mixture was cooled to 23° C. To the resulting mixture, 70 parts of chloroform and 5% oxalic acid were added. 25 parts of an aqueous solution was added, and the mixture was stirred at 23°C for 30 minutes, after which the organic layer was separated and taken out. 30 parts of ion-exchanged water was added to the organic layer and stirred at 23°C for 30 minutes, and then the organic layer was separated. This water washing procedure was repeated five times. The obtained organic layer was concentrated, and the concentrated residue was 50 parts of tert-butyl methyl ether was added, and the mixture was stirred at 23°C for 30 minutes. The liquid was removed and the mixture was concentrated. 50 parts of n-heptane was added to the resulting concentrated residue, and the mixture was stirred for 3 hours at 23°C. After stirring for 10 minutes, the mixture was filtered to obtain 6.88 parts of the salt represented by formula (I-76). . MASS(ESI(+)Spectrum):M + 317.1 MASS(ESI(-)Spectrum):M - 325.0

[0215] Resin synthesis The compounds (monomers) used in the synthesis of the resin are shown below. TIFF0007672459000141.tif3885Hereinafter, these monomers will be referred to as "monomer (a1-1-3)" etc. according to their formula numbers.

[0216] Synthesis Example 1 [Synthesis of Resin A1] As the monomers, the monomer (a1-4-2), the monomer (a1-1-3) and the monomer (a1-2-6) was used, and the molar ratio [monomer (a1-4-2):monomer (a1-1 -3):monomer (a1-2-6) in a ratio of 38:24:38, Furthermore, this monomer mixture was mixed with 1.5 times by mass of methyl methyl ester based on the total mass of all monomers. Isobutyl ketone was mixed in the resulting mixture, and azobisisobutyronite was added as an initiator. The amount of methyl acrylate was 7 mol % based on the total number of moles of all monomers. The polymerization was carried out by heating at 40°C for about 5 hours. An aqueous acid solution was added, and the mixture was stirred for 6 hours, followed by separation. The obtained organic layer was diluted with a large amount of n-heptane The resin was precipitated by pouring it into a flask, and then filtered and collected to obtain a resin with a weight-average molecular weight of approximately 4.6 × 10 3 Resin A1 (copolymer) having the following structural units was obtained in a yield of 74%. This is what we do. TIFF0007672459000142.tif29104

[0217] <Preparation of Resist Composition> As shown in Table 2, the following components were mixed, and the resulting mixture was passed through a fluorine-containing filter with a pore size of 0.2 μm. The mixture was filtered through a resin filter to prepare a resist composition. [Table 2]

[0218] <Resin (A)> A1: Resin A1 <Compound (I)> I-1: A salt represented by formula (I-1) I-4: Salt represented by formula (I-4) I-15: Salt represented by formula (I-15) I-61: A salt represented by formula (I-61) I-76: A salt represented by formula (I-76) I-91: A salt represented by formula (I-91) I-136: A salt represented by formula (I-136) IX-1: A salt represented by formula (IX-1) (see Examples in JP 2007-161707 A) (synthesized according to TIFF0007672459000144.tif2238IX-2: A salt represented by formula (IX-2) (Examples of JP-A-2011-121937) (synthesized according to TIFF0007672459000145.tif2549<Quencher (C)> C1: Synthesized by the method described in JP 2011-39502 A TIFF0007672459000146.tif3337<Solvent (E)> Propylene glycol monomethyl ether acetate 400 parts Propylene glycol monomethyl ether 100 parts γ-butyrolactone 5 parts

[0219] (Electron beam exposure evaluation of resist composition) A 6-inch silicon wafer is heated on a direct hot plate with hexamethyldisilazane. The silicon wafer was treated at 90°C for 60 seconds using a resist composition. The layer was spin-coated to a thickness of 0.04 μm. The substrate was prebaked on the sheet for 60 seconds at the temperature shown in the "PB" column of Table 2 to form a composition layer. The composition layer formed on the wafer was subjected to electron beam lithography using an electron beam lithography machine (ELS-F1 manufactured by Elionix Co., Ltd.). The exposure dose was gradually changed using a laser with an energy of 25 125 keV to form a contact hole pattern. (Hole pitch 40 nm / hole diameter 17 nm) was directly written. After exposure, the film was post-exposed on a hot plate for 60 seconds at the temperature shown in the "PEB" column of Table 2. The mixture was then baked in a 2.38% by mass aqueous solution of tetramethylammonium hydroxide. A resist pattern was obtained by paddle development with a liquid for 60 seconds. In the resist pattern obtained after development, the hole diameter formed using the mask was The exposure dose at which the hole diameter became 17 nm was defined as the effective sensitivity.

[0220] <CD Uniformity (CDU) Evaluation> At the effective sensitivity, the hole diameter of the pattern formed with a mask having a hole diameter of 17 nm was measured 24 times for one hole, and the average value was defined as the average hole diameter of one hole. The average hole diameter of the pattern formed with a mask having a hole diameter of 55 nm within the same wafer was measured at 400 locations and used as the population to calculate the standard deviation. The results are shown in Table 3. The numerical values in parentheses indicate the standard deviation (nm).

Table 3

Industrial Applicability

[0221] The resist composition containing the salt of the present invention can obtain a resist pattern having good CD uniformity (CDU), and thus is suitable for semiconductor microfabrication and is extremely useful industrially.​​​

Claims

1. A salt represented by formula (I): [In formula (I), Q 1 and Q. 2 each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. R 1 and R 2 each independently represents a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R 1 and R 2 may be the same or different from each other. X 1 is *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * is C(R 1 ) (R 2 ) or C(Q 1 ) (Q 2 ) represents the bonding position. L 1 represents a group formed by combining an alkanediyl group having 1 to 6 carbon atoms with an adamantanediyl group, and the —CH 2 At least one of - is replaced by -O- or -CO-. A 1 represents a divalent alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a halogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a combination thereof. R ａ represents a perfluoroalkyl group having 1 to 4 carbon atoms. Z + represents a cation represented by any one of formulas (b2-1) to (b2-4). [In formulas (b2-1) to (b2-4), R b4 ~R b6 each independently represent a chain hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, a hydrogen atom contained in the chain hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, 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 the —CH 2 - may be replaced by -O-, -S- or -CO-. R b7 and R b8 each independently represents a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent an integer of 0 to 5. When m2 is 2 or more, a plurality of R b7 may be the same or different, and when n2 is 2 or more, a plurality of R b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and the —CH 2 - 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 an open chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, a hydrogen atom contained in the open chain hydrocarbon may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including the —CH—CO— to which they are bonded, and the —CH 2 - may be replaced by -O-, -S- or -CO-. R b13 ~R b18 each independently represents a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. L b31 represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of 0 to 5. q2 and r2 each independently represent an integer of 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, multiple R b13 are the same or different, and when p2 is 2 or more, a plurality of R b14 are the same or different, and when q2 is 2 or more, a plurality of R b15 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.]

2. X 1 is *-CO-O- or *-O-CO- (where * is C(R 1 ) (R 2 ) or C(Q 1 ) (Q 2 2. The salt according to claim 1, wherein:

3. R ａ The salt according to claim 1 or 2, wherein is a trifluoromethyl group.

4. An acid generator comprising the salt according to any one of claims 1 to 3.

5. An acid generator containing the salt according to claim 4; and a resin that includes a structural unit having an acid labile group.

6. 6. The resist composition according to claim 5, wherein the structural unit having an acid labile group comprises at least two kinds of structural units represented by formula (a1-1) and formula (a1-2). [In formula (a1-1) and formula (a1-2), L a1 and L a2 are each independently -O- or *-O-(CH ２ ) k1 represents --CO--O--, k1 represents an integer of 1 to 7, and * represents a bond to --CO--. R a4 and R a5 each independently represents a hydrogen atom or a methyl group. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or a combination thereof. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

7. 7. The resist composition according to claim 5, wherein the resin containing a structural unit having an acid labile group further 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 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 -, * is -R a50 represents the bonding site with the carbon atom to which it is bonded. A a52 represents an alkanediyl group having 1 to 6 carbon atoms. X a51 and X a52 each independently represents -O-, -CO-O- or -O-CO-. nb represents 0 or 1. mb represents an integer of 0 to 4. When mb is an integer of 2 or more, a plurality of R a51 may be the same or different.

8. 8. The resist composition according to claim 5, further comprising a resin that includes a structural unit having a fluorine atom.

9. 9. The resist composition according to claim 5, further comprising a salt capable of generating an acid having a weaker acidity than the acid generated from the acid generator.

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

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