JP2009157040A - Resist composition and resist pattern forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resist composition capable of reducing defects and a resist pattern forming method. <P>SOLUTION: The resist composition includes a base component (A) of which the solubility in an alkali developer changes by the action of an acid and an acid generator component (B) which generates an acid upon exposure to light, wherein the acid generator component (B) includes a compound (B1) represented by general formula (b1) (wherein Q<SP>1</SP>is a divalent linking group containing an oxygen atom; Y<SP>1</SP>is a 1-4C alkylene group which may have a substituent or a 1-4C fluorinated alkylene group which may have a substituent; X is a 3-30C hydrocarbon group which may have a substituent; and A<SP>+</SP>is an organic cation) and a compound (B2) represented by general formula (b2) (wherein R<SP>4</SP>is a linear fluorinated alkyl group; and A'<SP>+</SP>is an organic cation). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resist composition and a resist pattern forming method using the resist composition.

In lithography technology, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed to radiation such as light or an electron beam through a mask on which a predetermined pattern is formed. And a development process is performed to form a resist pattern having a predetermined shape on the resist film. A resist material in which the exposed portion changes to a property that dissolves in the developer is referred to as a positive type, and a resist material that changes to a property in which the exposed portion does not dissolve in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has rapidly progressed due to advances in lithography technology.
As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used, but at present, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has started. In addition, studies have been made on F ₂ excimer lasers, electron beams, EUV (extreme ultraviolet rays), X-rays, and the like having shorter wavelengths than these excimer lasers.

  Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing a pattern with fine dimensions. As a resist material that satisfies these requirements, a chemical amplification containing a base material component that has film-forming ability and changes in solubility in an alkaline developer by the action of an acid, and an acid generator that generates an acid upon exposure. Type resist composition is used. For example, a positive chemically amplified resist composition contains a base component whose solubility in an alkaline developer is increased by the action of an acid, and an acid generator. When a resist film formed using such a resist composition is exposed, an acid is generated from the acid generator in the exposed portion, and the solubility of the base component in an alkaline developer is increased by the action of the acid. The exposed part becomes soluble in an alkaline developer.

Until now, resin (base resin) has been mainly used as the base resin for chemically amplified resists. For example, as a base resin for resist used in KrF excimer laser (248 nm) lithography, polyhydroxystyrene (PHS) or a resin (PHS resin) in which the hydroxyl group is protected with an acid dissociable, dissolution inhibiting group is used. Yes. In addition, as a resist base resin used in ArF excimer laser (193 nm) lithography or the like, a resin (acrylic resin) having a structural unit derived from (meth) acrylic acid ester in its main chain is generally used. ing. In the case of the positive type, as such a resin, a resin having a structural unit derived from a (meth) acrylic ester containing an acid dissociable, dissolution inhibiting group is mainly used (see, for example, Patent Documents 1 and 2).
The “(meth) acrylic acid ester” means one or both of an acrylic acid ester having a hydrogen atom bonded to the α-position and a methacrylic acid ester having a methyl group bonded to the α-position. “(Meth) acrylate” means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methacrylate having a methyl group bonded to the α-position. “(Meth) acrylic acid” means one or both of acrylic acid having a hydrogen atom bonded to the α-position and methacrylic acid having a methyl group bonded to the α-position.

A wide variety of acid generators used in chemically amplified resists have been proposed. For example, onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, diazomethane series, and the like. Acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like are known. Currently, an onium salt acid generator having an onium ion such as triphenylsulfonium in the cation moiety is used as the acid generator. The anion moiety of the onium salt acid generator is generally an alkyl sulfonate ion or a fluorinated alkyl sulfonate ion in which part or all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms (for example, Patent Documents). 3).
Japanese Patent No. 2881969 JP 2003-241385 A JP 2003-167347 A

However, the resist material as described above has a problem that defects are likely to occur on the surface of the resist pattern to be formed. Defects are general defects detected when a developed resist pattern is observed from directly above, for example, with a surface defect observation apparatus (trade name “KLA”) manufactured by KLA Tencor. Examples of such defects include scum, bubbles, dust, bridges (bridge structures between resist patterns), uneven color, and precipitates after development. Improving the defect becomes important as a resist pattern having high resolution is required.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a resist composition and a resist pattern forming method capable of reducing defects.

In order to achieve the above object, the present invention employs the following configuration.
That is, the first aspect of the present invention is a resist composition comprising a base material component (A) whose solubility in an alkaline developer changes by the action of an acid, and an acid generator component (B) that generates an acid upon exposure. A thing,
The acid generator component (B) contains a compound (B1) represented by the following general formula (b1) and a compound (B2) represented by the following general formula (b2). It is a composition.

［式中、Ｑ^１は酸素原子を含む２価の連結基であり、Ｙ^１は置換基を有していてもよい炭素数１〜４のアルキレン基または置換基を有していてもよい炭素数１〜４のフッ素化アルキレン基であり、Ｘは置換基を有していてもよい炭素数３〜３０の炭化水素基であり、Ａ^＋は有機カチオンである。］

[Wherein, Q ¹ is a divalent linking group containing an oxygen atom, and Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms or an optionally substituted carbon. A fluorinated alkylene group having 1 to 4 carbon atoms, X is an optionally substituted hydrocarbon group having 3 to 30 carbon atoms, and A ⁺ is an organic cation. ]

［式中、Ｒ^４は直鎖状のフッ素化アルキル基であり、Ａ’^＋は有機カチオンである。］

[Wherein R ⁴ is a linear fluorinated alkyl group, and A ′ ⁺ is an organic cation. ]

  According to a second aspect of the present invention, there is provided a step of forming a resist film on a support using the resist composition of the first aspect, a step of exposing the resist film, and an alkali development of the resist film. A resist pattern forming method including a step of forming a resist pattern.

In the present specification and claims, the “structural unit” means a monomer unit (monomer unit) constituting a resin component (polymer, copolymer).
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups.
“Lower alkyl group” means an alkyl group having 1 to 5 carbon atoms.
Unless otherwise specified, the “alkylene group” includes linear, branched and cyclic divalent saturated hydrocarbon groups.
“Exposure” is a concept that includes radiation exposure in general.

  ADVANTAGE OF THE INVENTION According to this invention, the resist composition and the resist pattern formation method which can reduce a defect can be provided.

≪Resist composition≫
The resist composition of the present invention comprises a base material component (A) whose solubility in an alkaline developer is changed by the action of an acid (hereinafter referred to as “component (A)”), and an acid generator component that generates an acid upon exposure ( B) (hereinafter referred to as component (B)).
When a resist film formed using such a resist composition is selectively exposed at the time of resist pattern formation, an acid is generated from the component (B), and the acid has a solubility in the alkaline developer of the component (A). Change. As a result, while the solubility of the exposed portion of the resist film in the alkaline developer changes, the unexposed portion does not change the solubility in the alkaline developer. In the case of the negative type, the unexposed part is dissolved and removed, and a resist pattern is formed.
The resist composition of the present invention may be a negative resist composition or a positive resist composition.

<(A) component>
As the component (A), organic compounds that are usually used as base components for chemically amplified resists can be used alone or in combination of two or more.
Here, the “base material component” is an organic compound having a film forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film-forming ability is improved and a nano-level resist pattern is easily formed.
The organic compound having a molecular weight of 500 or more is largely classified into a low molecular weight organic compound having a molecular weight of 500 to less than 2000 (hereinafter referred to as a low molecular compound) and a high molecular weight resin having a molecular weight of 2000 or more (polymer material). Separated. As the low molecular weight compound, a non-polymer is usually used. In the case of a resin (polymer, copolymer), a polystyrene-reduced mass average molecular weight by GPC (gel permeation chromatography) is used as the “molecular weight”. Hereinafter, the term “resin” refers to a resin having a molecular weight of 2000 or more.
As the component (A), a resin whose alkali solubility is changed by the action of an acid can be used, and a low molecular weight material whose alkali solubility is changed by the action of an acid can also be used.

When the resist composition of the present invention is a negative resist composition, a base component that is soluble in an alkaline developer is used as the component (A), and a crosslinking agent is further added to the negative resist composition.
In such a negative resist composition, when an acid is generated from the component (B) by exposure, the acid acts to cause cross-linking between the base component and the cross-linking agent, resulting in poor solubility in an alkali developer. To do. Therefore, in the formation of the resist pattern, when the resist film obtained by coating the negative resist composition on the substrate is selectively exposed, the exposed portion turns into poorly soluble in an alkaline developer, while unexposed. Since the portion remains soluble in the alkali developer and does not change, a resist pattern can be formed by alkali development.
As the component (A) of the negative resist composition, a resin that is soluble in an alkali developer (hereinafter referred to as an alkali-soluble resin) is usually used.
As the alkali-soluble resin, a resin having a unit derived from at least one selected from α- (hydroxyalkyl) acrylic acid or a lower alkyl ester of α- (hydroxyalkyl) acrylic acid is a good resist with little swelling. A pattern can be formed, which is preferable. Note that α- (hydroxyalkyl) acrylic acid includes acrylic acid in which a hydrogen atom is bonded to the α-position carbon atom to which the carboxy group is bonded, and a hydroxyalkyl group (preferably having 1 carbon atom) in the α-position carbon atom. One or both of [alpha] -hydroxyalkylacrylic acids to which (5) hydroxyalkyl groups) are attached.
As the crosslinking agent, for example, it is usually preferable to use an amino crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group because a good resist pattern with less swelling can be formed. It is preferable that the compounding quantity of a crosslinking agent is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

  When the resist composition of the present invention is a positive resist composition, as the component (A), a base material component whose solubility in an alkaline developer is increased by the action of an acid is used. The component (A) is hardly soluble in an alkali developer before exposure. When an acid is generated from the component (B) by exposure, the solubility in the alkali developer is increased by the action of the acid. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the positive resist composition on the substrate is selectively exposed, the exposed portion changes from poorly soluble to soluble in an alkaline developer. On the other hand, since the unexposed portion remains hardly soluble in alkali and does not change, a resist pattern can be formed by alkali development.

In the resist composition of the present invention, the component (A) is preferably a base material component whose solubility in an alkaline developer is increased by the action of an acid. That is, the resist composition of the present invention is preferably a positive resist composition.
The component (A) may be a resin component (A1) (hereinafter also referred to as component (A1)) whose solubility in an alkaline developer is increased by the action of an acid. It may be a low molecular compound (A2) (hereinafter sometimes referred to as the component (A2)) whose solubility in a liquid is increased, or a mixture thereof.
In the present invention, the component (A) preferably contains the component (A1).

[(A1) component]
As the component (A1), resin components (base resins) that are usually used as base components for chemically amplified resists can be used alone or in combination of two or more.
In the present invention, the component (A1) preferably contains a structural unit derived from an acrylate ester.
Here, in the present specification and claims, the “structural unit derived from an acrylate ester” means a structural unit formed by cleavage of an ethylenic double bond of an acrylate ester.
“Acrylic acid esters” include not only acrylic acid esters in which a hydrogen atom is bonded to the α-position carbon atom, but also those in which a substituent (an atom or group other than a hydrogen atom) is bonded to the α-position carbon atom. Include concepts. Examples of the substituent include a lower alkyl group and a halogenated lower alkyl group.
Note that the α position (α-position carbon atom) of a structural unit derived from an acrylate ester means a carbon atom to which a carbonyl group is bonded unless otherwise specified.
In the acrylate ester, as the lower alkyl group as a substituent at the α-position, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, Examples include lower linear or branched alkyl groups such as isopentyl group and neopentyl group.
Specific examples of the halogenated lower alkyl group include groups in which part or all of the hydrogen atoms in the above-mentioned “lower alkyl group as a substituent at the α-position” are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
In the present invention, the α-position of the acrylate ester is preferably a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and is a hydrogen atom, a lower alkyl group or a fluorinated lower alkyl group. In view of industrial availability, a hydrogen atom or a methyl group is most preferable.

The component (A1) particularly preferably has a structural unit (a1) derived from an acrylate ester containing an acid dissociable, dissolution inhibiting group.
In addition to the structural unit (a1), the component (A1) preferably further has a structural unit (a2) derived from an acrylate ester containing a lactone-containing cyclic group.
The component (A1) is a structural unit derived from an acrylate ester containing a polar group-containing aliphatic hydrocarbon group in addition to the structural unit (a1) or in addition to the structural units (a1) and (a2). It is preferable to have (a3).

-Structural unit (a1):
The acid dissociable, dissolution inhibiting group in the structural unit (a1) has an alkali dissolution inhibiting property that makes the entire component (A1) difficult to dissolve in an alkali developer before dissociation, and dissociates with an acid. This increases the solubility of the entire component in an alkaline developer, and those that have been proposed as acid dissociable, dissolution inhibiting groups for base resins for chemically amplified resists can be used. In general, a group that forms a cyclic or chain tertiary alkyl ester with a carboxy group in (meth) acrylic acid or the like; an acetal-type acid dissociable, dissolution inhibiting group such as an alkoxyalkyl group is widely known. .

Here, the “tertiary alkyl ester” is an ester formed by replacing a hydrogen atom of a carboxy group with a chain or cyclic alkyl group, and the carbonyloxy group (—C (O)). A structure in which the tertiary carbon atom of the chain or cyclic alkyl group is bonded to the terminal oxygen atom of -O-). In this tertiary alkyl ester, when an acid acts, a bond is cut between an oxygen atom and a tertiary carbon atom.
The chain or cyclic alkyl group may have a substituent.
Hereinafter, a group that is acid dissociable by constituting a carboxy group and a tertiary alkyl ester is referred to as a “tertiary alkyl ester type acid dissociable, dissolution inhibiting group” for convenience.
Examples of the tertiary alkyl ester type acid dissociable, dissolution inhibiting group include an aliphatic branched acid dissociable, dissolution inhibiting group and an acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group.

Here, “aliphatic” in the claims and the specification is a relative concept with respect to aromatics, and is defined to mean groups, compounds, and the like that do not have aromaticity.
“Aliphatic branched” means having a branched structure having no aromaticity. The structure of the “aliphatic branched acid dissociable, dissolution inhibiting group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated.
As the aliphatic branched acid dissociable, dissolution inhibiting group, a tertiary alkyl group having 4 to 8 carbon atoms is preferable, and specific examples include a tert-butyl group, a tert-pentyl group, and a tert-heptyl group. .

The “aliphatic cyclic group” means a monocyclic group or a polycyclic group having no aromaticity.
The “aliphatic cyclic group” in the structural unit (a1) may or may not have a substituent. Examples of the substituent include a lower alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (= O), and the like.
The basic ring structure excluding the substituent of the “aliphatic cyclic group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated. The “aliphatic cyclic group” is preferably a polycyclic group.
Examples of the aliphatic cyclic group include monocycloalkanes, bicycloalkanes, tricycloalkanes, tetracycloalkanes which may or may not be substituted with a lower alkyl group, a fluorine atom or a fluorinated alkyl group. And groups obtained by removing one or more hydrogen atoms from a polycycloalkane. More specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. .

  Examples of the acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group include a group having a tertiary carbon atom on the ring skeleton of a cyclic alkyl group. Specifically, 2-methyl-2 -Adamantyl group, 2-ethyl-2-adamantyl group, etc. are mentioned. Alternatively, in the structural units represented by the following general formulas (a1 ″ -1) to (a1 ″ -6), an adamantyl group such as a group bonded to an oxygen atom of a carbonyloxy group (—C (O) —O—) An aliphatic cyclic group such as a cyclohexyl group, a cyclopentyl group, a norbornyl group, a tricyclodecanyl group, or a tetracyclododecanyl group, and a branched alkylene group having a tertiary carbon atom bonded thereto. Groups.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｒ^１５、Ｒ^１６はアルキル基（直鎖状、分岐鎖状のいずれでもよく、好ましくは炭素数１〜５である）を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ¹⁵ and R ¹⁶ may be alkyl groups (both linear and branched, preferably 1 to 5 carbon atoms). Is). ]

  In the general formulas (a1 ″ -1) to (a1 ″ -6), the lower alkyl group or halogenated lower alkyl group of R is a lower alkyl group or halogenated lower alkyl which may be bonded to the α-position of the acrylate ester. It is the same as the alkyl group.

The “acetal-type acid dissociable, dissolution inhibiting group” is generally bonded to an oxygen atom by substituting a hydrogen atom at the terminal of an alkali-soluble group such as a carboxy group or a hydroxyl group. When an acid is generated by exposure, this acid acts to break the bond between the acetal acid dissociable, dissolution inhibiting group and the oxygen atom to which the acetal acid dissociable, dissolution inhibiting group is bonded.
Examples of the acetal type acid dissociable, dissolution inhibiting group include a group represented by the following general formula (p1).

［式中、Ｒ^１’，Ｒ^２’はそれぞれ独立して水素原子または低級アルキル基を表し、ｎは０〜３の整数を表し、Ｙは低級アルキル基または脂肪族環式基を表す。］

[Wherein, R ¹ ′ and R ² ′ each independently represents a hydrogen atom or a lower alkyl group, n represents an integer of 0 to 3, and Y represents a lower alkyl group or an aliphatic cyclic group. ]

In the above formula, n is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.
Examples of the lower alkyl group for R ¹ ′ and R ² ′ include the same lower alkyl groups as those described above for R. A methyl group or an ethyl group is preferable, and a methyl group is most preferable.
In the present invention, it is preferable that at least one of R ¹ ′ and R ² ′ is a hydrogen atom. That is, the acid dissociable, dissolution inhibiting group (p1) is preferably a group represented by the following general formula (p1-1).

［式中、Ｒ^１’、ｎ、Ｙは上記と同様である。］

Wherein, ^{R 1} ', n, Y are as defined above. ]

Examples of the lower alkyl group for Y include the same lower alkyl groups as those described above for R.
The aliphatic cyclic group for Y can be appropriately selected from monocyclic or polycyclic aliphatic cyclic groups that have been proposed in a number of conventional ArF resists. For example, the above “aliphatic ring” Examples thereof are the same as those in the formula group.

  Examples of the acetal type acid dissociable, dissolution inhibiting group also include a group represented by the following general formula (p2).

［式中、Ｒ^１７、Ｒ^１８はそれぞれ独立して直鎖状もしくは分岐鎖状のアルキル基または水素原子であり、Ｒ^１９は直鎖状、分岐鎖状または環状のアルキル基である。または、Ｒ^１７およびＲ^１９がそれぞれ独立に直鎖状または分岐鎖状のアルキレン基であって、Ｒ^１７の末端とＲ^１９の末端とが結合して環を形成していてもよい。］

[Wherein, R ¹⁷ and R ¹⁸ each independently represent a linear or branched alkyl group or a hydrogen atom, and R ¹⁹ represents a linear, branched or cyclic alkyl group. Alternatively, R ¹⁷ and R ¹⁹ may be each independently a linear or branched alkylene group, and the end of R ^{17 and} the end of R ¹⁹ may be bonded to form a ring. ]

In R ¹⁷ and R ¹⁸ , the alkyl group preferably has 1 to 15 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group.
In particular, it is preferable that one of R ¹⁷ and R ¹⁸ is a hydrogen atom and the other is a methyl group.
R ¹⁹ is a linear, branched or cyclic alkyl group, preferably having 1 to 15 carbon atoms, and may be any of linear, branched or cyclic.
When R ¹⁹ is linear or branched, it preferably has 1 to 5 carbon atoms, more preferably an ethyl group or a methyl group, and most preferably an ethyl group.
When R ¹⁹ is cyclic, it preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, one or more polycycloalkanes such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group, are included. Examples include groups excluding hydrogen atoms. Specific examples thereof include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
In the above formula, R ¹⁷ and R ¹⁹ are each independently a linear or branched alkylene group (preferably an alkylene group having 1 to 5 carbon atoms), and the end of R ^{19 and} the end of R ¹⁷ And may be combined.
In this case, a cyclic group is formed by R ¹⁷ , R ¹⁹ , the oxygen atom to which R ¹⁹ is bonded, and the carbon atom to which the oxygen atom and R ¹⁷ are bonded. The cyclic group is preferably a 4-7 membered ring, and more preferably a 4-6 membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

  As the structural unit (a1), one or more selected from the group consisting of structural units represented by the following general formula (a1-0-1) and structural units represented by the following general formula (a1-0-2): Is preferably used.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｘ^１は酸解離性溶解抑制基を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; and X ¹ represents an acid dissociable, dissolution inhibiting group. ]

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｘ^２は酸解離性溶解抑制基を示し；Ｙ^２はアルキレン基または脂肪族環式基を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; X ² represents an acid dissociable, dissolution inhibiting group; Y ² represents an alkylene group or an aliphatic cyclic group. ]

In general formula (a1-0-1), the lower alkyl group or halogenated lower alkyl group for R is the same as the lower alkyl group or halogenated lower alkyl group that may be bonded to the α-position of the acrylate ester. .
X ¹ is not particularly limited as long as it is an acid dissociable, dissolution inhibiting group, and examples thereof include the above-described tertiary alkyl ester type acid dissociable, dissolution inhibiting group and acetal type acid dissociable, dissolution inhibiting group. And tertiary alkyl ester type acid dissociable, dissolution inhibiting groups are preferred.

In general formula (a1-0-2), R is the same as defined above.
X ² is the same as X ¹ in formula (a1-0-1).
Y ² is preferably an alkylene group having 1 to 10 carbon atoms or a divalent aliphatic cyclic group, and a group in which two or more hydrogen atoms are removed is used as the aliphatic cyclic group. Except for the above, the same “aliphatic cyclic group” as described above can be used.
When Y ² is an alkylene group having 1 to 10 carbon atoms, it is more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. .
When Y ² is a divalent aliphatic cyclic group, a group in which two or more hydrogen atoms have been removed from cyclopentane, cyclohexane, norbornane, isobornane, adamantane, tricyclodecane, or tetracyclododecane is particularly preferable. .

  More specifically, examples of the structural unit (a1) include structural units represented by the following general formulas (a1-1) to (a1-4).

［式中、Ｘ’は第３級アルキルエステル型酸解離性溶解抑制基を表し、Ｙは炭素数１〜５の低級アルキル基、または脂肪族環式基を表し；ｎは０〜３の整数を表し；Ｙ^２はアルキレン基または脂肪族環式基を表し；Ｒは前記と同じであり、Ｒ^１’、Ｒ^２’はそれぞれ独立して水素原子または炭素数１〜５の低級アルキル基を表す。］

[Wherein, X ′ represents a tertiary alkyl ester type acid dissociable, dissolution inhibiting group, Y represents a lower alkyl group having 1 to 5 carbon atoms, or an aliphatic cyclic group; n represents an integer of 0 to 3] Y ² represents an alkylene group or an aliphatic cyclic group; R is the same as defined above, and R ¹ ′ and R ² ′ each independently represent a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms. To express. ]

Wherein, X 'include those of the same tertiary alkyl ester-type acid dissociable, dissolution inhibiting groups as those described above for X ^{1.
R 1 ', R 2',} n, as the Y, respectively, ^{R 1} in the general formula listed in the description of "acetal-type acid dissociable, dissolution inhibiting group" described above ^{(p1) ', R 2'} , n, Y The same thing is mentioned.
The Y ^2, the same groups as those described above for ^{Y 2} in the general formula (a1-0-2).

  Specific examples of the structural units represented by the general formulas (a1-1) to (a1-4) are shown below.

As the structural unit (a1), one type may be used alone, or two or more types may be used in combination.
Among the above, the structural unit represented by the general formula (a1-1) is preferable, specifically, (a1-1-1) to (a1-1-6) and (a1-1-35) to (a1). More preferably, at least one selected from the group consisting of -1-41) is used.
Furthermore, as the structural unit (a1), in particular, those represented by the following general formula (a1-1-01) including the structural units of the formula (a1-1-1) to the formula (a1-1-4) The following general formula (a1-1-02) including the structural units of formulas (a1-1-35) to (a1-1-41) is also preferable.

（式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し、Ｒ^１１は低級アルキル基を示す。）

(In the formula, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and R ¹¹ represents a lower alkyl group.)

（式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し、Ｒ^１２は低級アルキル基を示す。ｈは１〜３の整数を表す。）

(Wherein R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ¹² represents a lower alkyl group, and h represents an integer of 1 to 3).

In general formula (a1-1-01), R is the same as defined above.
The lower alkyl group for R ^{11 is the same as} the lower alkyl group for R, and is preferably a methyl group or an ethyl group.
In general formula (a1-1-02), R is the same as defined above.
The lower alkyl group for R ^{12 is the same as} the lower alkyl group for R, preferably a methyl group or an ethyl group, and most preferably an ethyl group. h is preferably 1 or 2, and most preferably 2.

As the structural unit (a1), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a1) is preferably 10 to 80 mol%, more preferably 20 to 70 mol%, and more preferably 25 to 50 mol% with respect to all the structural units constituting the component (A1). Is more preferable. By setting it to the lower limit value or more, a pattern can be easily obtained when the resist composition is used, and by setting it to the upper limit value or less, it is possible to balance with other structural units.

Structural unit (a2):
The structural unit (a2) is a structural unit derived from an acrylate ester containing a lactone-containing cyclic group.
Here, the lactone-containing cyclic group refers to a cyclic group containing one ring (lactone ring) containing an —O—C (O) — structure. The lactone ring is counted as the first ring, and when it is only the lactone ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure.
The lactone cyclic group of the structural unit (a2) has an affinity for a developer containing water or a polymer compound (A1) when the polymer compound (A1) is used for forming a resist film. It is effective in enhancing the sex.

As the structural unit (a2), any unit can be used without any particular limitation.
Specifically, examples of the lactone-containing monocyclic group include groups in which one hydrogen atom has been removed from γ-butyrolactone. Examples of the lactone-containing polycyclic group include groups in which one hydrogen atom has been removed from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring.

  More specifically, examples of the structural unit (a2) include structural units represented by general formulas (a2-1) to (a2-5) shown below.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基であり、Ｒ’は水素原子、低級アルキル基、炭素数１〜５のアルコキシ基または−ＣＯＯＲ”であり、前記Ｒ”は水素原子、または炭素数１〜１５の直鎖状、分岐鎖状もしくは環状のアルキル基であり、ｍは０または１の整数であり、Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子である。］

[Wherein, R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ′ is a hydrogen atom, a lower alkyl group, an alkoxy group having 1 to 5 carbon atoms, or —COOR ″, and the above R ″ is A hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms, m is an integer of 0 or 1, and A ″ is a carbon which may contain an oxygen atom or a sulfur atom. It is an alkylene group of formula 1 to 5, an oxygen atom or a sulfur atom.

R in the general formulas (a2-1) to (a2-5) is the same as R in the structural unit (a1).
Examples of the lower alkyl group for R ′ include the same as the lower alkyl group for R in the structural unit (a1).
When R ″ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, and more preferably 1 to 5 carbon atoms.
When R ″ is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a fluorine atom or Groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane, which may or may not be substituted with a fluorinated alkyl group Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Is mentioned.
In general formulas (a2-1) to (a2-5), R ′ is preferably a hydrogen atom in view of industrial availability.
Specific examples of the alkylene group having 1 to 5 carbon atoms that may contain an oxygen atom or sulfur atom of A ″ include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, —O—CH ₂ —. _{, -CH 2 -O-CH 2 -} , - S-CH 2 -, - CH 2 -S-CH 2 - , and the like.
Below, the specific structural unit of the said general formula (a2-1)-(a2-5) is illustrated.

  As the structural unit (a2), at least one selected from the group consisting of structural units represented by the general formulas (a2-1) to (a2-5) is preferable, and the general formulas (a2-1) to ( At least one selected from the group consisting of structural units represented by a2-3) is more preferred. Among them, chemical formulas (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-2), (a2-2-9), (a2-2-10) ), (A2-3-1), (a2-3-2), (a2-3-9) and (a2-3-10), and at least one selected from the group consisting of structural units represented by preferable.

As the structural unit (a2), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a2) is preferably 5 to 60 mol%, more preferably 10 to 50 mol%, based on the total of all the structural units constituting the component (A1). 50 mol% is more preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by setting the upper limit value or less, it is possible to balance with other structural units.

-Structural unit (a3):
The structural unit (a3) is a structural unit derived from an acrylate ester containing a polar group-containing aliphatic hydrocarbon group.
When the component (A1) has the structural unit (a3), the hydrophilicity of the component (A1) is increased, the affinity with the developer is increased, the alkali solubility in the exposed area is improved, and the resolution is improved. Contributes to improvement.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group is substituted with a fluorine atom. A hydroxyl group is particularly preferable.
Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a polycyclic aliphatic hydrocarbon group (polycyclic group). It is done. As the polycyclic group, for example, a resin for a resist composition for ArF excimer laser can be appropriately selected from among many proposed ones. The polycyclic group preferably has 7 to 30 carbon atoms.
Among them, a structural unit derived from an acrylate ester containing an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of hydrogen atoms of a hydroxyl group, a cyano group, a carboxy group, or an alkyl group is substituted with a fluorine atom Is more preferable. Examples of the polycyclic group include groups in which two or more hydrogen atoms have been removed from bicycloalkane, tricycloalkane, tetracycloalkane and the like. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane. Industrially preferable.

  The structural unit (a3) is derived from a hydroxyethyl ester of acrylic acid when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms. When the hydrocarbon group is a polycyclic group, a structural unit represented by the following formula (a3-1), a structural unit represented by (a3-2), (a3-3) ) Is preferable.

（式中、Ｒは前記と同じであり、ｊは１〜３の整数であり、ｋは１〜３の整数であり、ｔ’は１〜３の整数であり、ｌは１〜５の整数であり、ｓは１〜３の整数である。）

Wherein R is the same as above, j is an integer of 1 to 3, k is an integer of 1 to 3, t 'is an integer of 1 to 3, and l is an integer of 1 to 5. And s is an integer of 1 to 3.)

In formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group.
j is preferably 1, and a hydroxyl group bonded to the 3-position of the adamantyl group is particularly preferred.
In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.
In formula (a3-3), t ′ is preferably 1. l is preferably 1. s is preferably 1. These preferably have a 2-norbornyl group or a 3-norbornyl group bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5th or 6th position of the norbornyl group.

As the structural unit (a3), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a3) is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, and more preferably 5 to 25 mol% with respect to all the structural units constituting the component (A1). Is more preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a3) is sufficiently obtained, and by setting the upper limit value or less, it is possible to balance with other structural units.

Structural unit (a4):
The component (A1) may contain other structural units (a4) other than the structural units (a1) to (a3) as long as the effects of the present invention are not impaired.
The structural unit (a4) is not particularly limited as long as it is another structural unit not classified into the above structural units (a1) to (a3), and for ArF excimer laser, for KrF excimer laser (preferably ArF excimer) A number of hitherto known materials can be used for resist resins such as lasers.
As the structural unit (a4), for example, a structural unit derived from an acrylate ester containing a non-acid-dissociable aliphatic polycyclic group is preferable. Examples of the polycyclic group include those exemplified in the case of the structural unit (a1), and for ArF excimer laser and KrF excimer laser (preferably for ArF excimer laser). A number of hitherto known materials can be used as the resin component of the resist composition.
In particular, at least one selected from a tricyclodecanyl group, an adamantyl group, a tetracyclododecanyl group, an isobornyl group, and a norbornyl group is preferable in terms of industrial availability. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.
Specific examples of the structural unit (a4) include those represented by the following general formulas (a4-1) to (a4-5).

（式中、Ｒは前記と同じである。）

(In the formula, R is as defined above.)

  When the structural unit (a4) is contained in the component (A1), the proportion of the structural unit (a4) in the component (A1) is 1 to 30 with respect to the total of all the structural units constituting the component (A1). Mol% is preferable and 10 to 20 mol% is more preferable.

  In the present invention, the component (A1) preferably contains a copolymer having the structural units (a1), (a2) and (a3). Examples of the copolymer include copolymers composed of the structural units (a1), (a2) and (a3), copolymers composed of the structural units (a1), (a2), (a3) and (a4). Can be mentioned.

The component (A1) can be obtained by polymerizing a monomer for deriving each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN).
Further, for the component (A1), in the polymerization, a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH is used in combination, so that the terminal A —C (CF ₃ ) ₂ —OH group may be introduced into the. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing

The mass average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of the component (A1) is not particularly limited, but is preferably 2000 to 50000, more preferably 3000 to 30000, and 5000 to 20000. Most preferred. When it is smaller than the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist. When it is larger than the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
Further, the dispersity (Mw / Mn) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5. In addition, Mn shows a number average molecular weight.

[(A2) component]
As the component (A2), a low molecular compound having a molecular weight of 500 or more and less than 2000 and having an acid dissociable, dissolution inhibiting group and a hydrophilic group as exemplified in the description of the component (A1) above is preferable. Specifically, a compound in which a part of hydrogen atoms of a hydroxyl group of a compound having a plurality of phenol skeletons is substituted with the acid dissociable, dissolution inhibiting group can be mentioned.
The component (A2) is, for example, a part of the hydrogen atom of the hydroxyl group of a low molecular weight phenol compound known as a sensitizer in a non-chemically amplified g-line or i-line resist or a heat resistance improver. Those substituted with a soluble dissolution inhibiting group are preferred and can be arbitrarily used.
Examples of such low molecular weight phenol compounds include bis (4-hydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2- (4-hydroxyphenyl) -2- (4′-hydroxyphenyl). ) Propane, 2- (2,3,4-trihydroxyphenyl) -2- (2 ′, 3 ′, 4′-trihydroxyphenyl) propane, tris (4-hydroxyphenyl) methane, bis (4-hydroxy-) 3,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3, 4-dihydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -3,4-dihydroxyph Phenylmethane, bis (4-hydroxy-3-methylphenyl) -3,4-dihydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl- 4-hydroxy-6-methylphenyl) -3,4-dihydroxyphenylmethane, 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene, Examples include 2, 3, 4 nuclei of formalin condensates of phenols such as phenol, m-cresol, p-cresol or xylenol. Of course, it is not limited to these.
The acid dissociable, dissolution inhibiting group is not particularly limited, and examples thereof include those described above.

As the component (A), one type may be used alone, or two or more types may be used in combination.
In the resist composition of the present invention, the content of the component (A) may be adjusted according to the resist film thickness to be formed.

<(B) component>
The component (B) includes a compound (B1) represented by the following general formula (b1) (hereinafter referred to as (B1) component) and a compound (B2) represented by the following general formula (b2) (hereinafter referred to as ( B2) component)).

［式中、Ｑ^１は酸素原子を含む２価の連結基であり、Ｙ^１は置換基を有していてもよい炭素数１〜４のアルキレン基または置換基を有していてもよい炭素数１〜４のフッ素化アルキレン基であり、Ｘは置換基を有していてもよい炭素数３〜３０の炭化水素基であり、Ａ^＋は有機カチオンである。］

[Wherein, Q ¹ is a divalent linking group containing an oxygen atom, and Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms or an optionally substituted carbon. A fluorinated alkylene group having 1 to 4 carbon atoms, X is an optionally substituted hydrocarbon group having 3 to 30 carbon atoms, and A ⁺ is an organic cation. ]

［式中、Ｒ^４は直鎖状のフッ素化アルキル基であり、Ａ’^＋は有機カチオンである。］

[Wherein R ⁴ is a linear fluorinated alkyl group, and A ′ ⁺ is an organic cation. ]

[(B1) component]
In formula (b1), Q ¹ is a divalent linking group containing an oxygen atom.
Q ¹ may contain an atom other than an oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, oxygen atoms, sulfur atoms, and nitrogen atoms.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond; —O—), an ester bond (—C (═O) —O—), and an amide bond (—C (═O) —NH. -), A carbonyl group (-C (= O)-), a non-hydrocarbon oxygen atom-containing linking group such as a carbonate bond (-O-C (= O) -O-); the non-hydrocarbon oxygen atom Examples include a combination of a containing linking group and an alkylene group.
Examples of the combination include —R ⁹¹ —O—, —R ⁹² —O—C (═O) — (wherein R ^{91 to} R ⁹² are each independently an alkylene group).
The alkylene group is preferably a linear or branched alkylene group, and the alkylene group preferably has 1 to 12 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably 1 to 3 carbon atoms.
Specific examples of the alkylene group include a methylene group [—CH ₂ —]; —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, —C (CH ₃ ) ₂ —, —C ( _{CH 3) (CH 2 CH 3} ) -, - C (CH 3) (CH 2 CH 2 CH 3) -, - C (CH 2 CH 3) 2 - ; alkylethylene groups such as ethylene group _[-CH 2 CH _2— ]; —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH (CH ₃ ) —, —C (CH ₃ ) ₂ CH ₂ —, —CH (CH ₂ CH ₃ ) CH ₂ —, Alkylethylene groups such as —CH (CH ₂ CH ₃ ) CH ₂ —; trimethylene group (n-propylene group) [—CH ₂ CH ₂ CH ₂ —]; —CH (CH ₃ ) CH ₂ CH ₂ —, —CH _{2 CH (CH 3) CH 2} - alkyl trimethylene group and the like; Toramechiren group _{[-CH 2 CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 CH 2 - alkyl tetramethylene group and the like; penta And methylene group [—CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ —] and the like.

Q ¹ is preferably a divalent linking group containing an ester bond or an ether bond. Among them, an ester bond, an ether bond, —R ⁹¹ —O—, or —R ⁹² —O—C (═O) — is preferred. An ester bond is particularly preferable.

In formula (b1), examples of the alkylene group for Y ¹ include the same alkylene groups as those described above for Q ¹ having 1 to 4 carbon atoms.
Examples of the fluorinated alkylene group include groups in which part or all of the hydrogen atoms of the alkylene group have been substituted with fluorine atoms.
As Y ^1, _{specifically, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF (CF 2 CF 3) -, _{-C (CF 3) 2 -,} - CF 2 CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF ₃ ) —, —C (CF ₃ ) ₂ CF ₂ —, —CF (CF ₂ CF ₃ ) CF ₂ —, —CF (CF ₂ CF ₂ CF ₃ ) —, —C (CF ₃ ) (CF _{2 CF 3) -; - CHF} -, - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -, - CH (CF 3) CH 2 -, - CH (CF 2 _{CF 3) -, - C (} CH 3) (CF 3) -, - CH 2 CH 2 CH 2 CF 2 -, - C H ₂ CH ₂ CF ₂ CF ₂ —, —CH (CF ₃ ) CH ₂ CH ₂ —, —CH ₂ CH (CF ₃ ) CH ₂ —, —CH (CF ₃ ) CH (CF ₃ ) —, —C ( _{CF 3) 2 CH 2 -;} - CH 2 -, - CH 2 CH 2 -, - CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 -, - CH (CH 2 CH 3) -, - _{C (CH 3) 2 -,} - CH 2 CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 CH 2 -, - CH 2 CH (CH 3) CH 2 -, - CH (CH 3) CH _{(CH 3) -, - C} (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - CH (CH 2 CH 2 CH 3) -, - C (CH 3) (CH 2 CH ₃ ) — and the like.

Y ¹ is preferably a fluorinated alkylene group, and particularly preferably a fluorinated alkylene group in which the carbon atom bonded to the adjacent sulfur atom is fluorinated. Examples of such fluorinated alkylene _{group, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF 2 CF 2 CF 2 CF 2 _{-, - CF (CF 3)} CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF 3) -, - C (CF 3) 2 CF 2 -, _{-CF (CF 2 CF 3) CF} 2 -; - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -; - CH 2 CH 2 CH 2 CF 2 -, - CH ₂ CH ₂ CF ₂ CF ₂ —, —CH ₂ CF ₂ CF ₂ CF ₂ — and the like can be mentioned.
Of _{these, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, or _CH 2 _CF 2 CF ₂ - is _{preferable, -CF 2 -, - CF 2} CF 2 - or -CF ₂ CF ₂ CF ₂ - is more preferable, -CF ₂ - is particularly preferred.

The alkylene group or fluorinated alkylene group may have a substituent. An alkylene group or a fluorinated alkylene group has a “substituent” means that part or all of the hydrogen atom or fluorine atom in the alkylene group or fluorinated alkylene group is substituted with an atom or group other than a hydrogen atom and a fluorine atom. Means that
Examples of the substituent that the alkylene group or fluorinated alkylene group may have include an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and a hydroxyl group.

In the formula (b1), the hydrocarbon group of X may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group.
The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and most preferably 6 to 12. However, the carbon number does not include the carbon number in the substituent.
Specific examples of the aromatic hydrocarbon group include a hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. Aryl groups such as aryl group, benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc., from which one is removed. The carbon number of the alkyl chain in the arylalkyl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.
The aromatic hydrocarbon group may have a substituent. For example, a part of carbon atoms constituting the aromatic ring of the aromatic hydrocarbon group may be substituted with a hetero atom, and the hydrogen atom bonded to the aromatic ring of the aromatic hydrocarbon group is substituted with the substituent. May be.
Examples of the former include heteroaryl groups in which some of the carbon atoms constituting the ring of the aryl group are substituted with heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and aromatic hydrocarbons in the arylalkyl groups. Examples include heteroarylalkyl groups in which some of the carbon atoms constituting the ring are substituted with the above heteroatoms.
Examples of the substituent of the aromatic hydrocarbon group in the latter example include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
The alkyl group as a substituent of the aromatic hydrocarbon group is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. preferable.
The alkoxy group as a substituent of the aromatic hydrocarbon group is preferably an alkoxy group having 1 to 5 carbon atoms, and is a methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert- A butoxy group is preferable, and a methoxy group and an ethoxy group are most preferable.
Examples of the halogen atom as a substituent for the aromatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent of the aromatic hydrocarbon group include groups in which part or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

The aliphatic hydrocarbon group for X may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be linear, branched or cyclic.
In X, the aliphatic hydrocarbon group may have a part of the carbon atoms constituting the aliphatic hydrocarbon group substituted by a substituent containing a hetero atom, and the hydrogen atom constituting the aliphatic hydrocarbon group May be substituted with a substituent containing a hetero atom.
The “heteroatom” in X is not particularly limited as long as it is an atom other than a carbon atom and a hydrogen atom, and examples thereof include a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom.
The substituent containing a hetero atom may be composed of only the hetero atom, or may be a group containing a group or atom other than the hetero atom.
Specific examples of the substituent for substituting a part of the carbon atom include —O—, —C (═O) —O—, —C (═O) —, —O—C (═O) —O. —, —C (═O) —NH—, —NH— (H may be substituted with a substituent such as an alkyl group, an acyl group, etc.), —S—, —S (═O) ₂ —, — S (= O) ₂ —O— and the like can be mentioned. When the aliphatic hydrocarbon group is cyclic, these substituents may be included in the ring structure.
Specific examples of the substituent that substitutes part or all of the hydrogen atoms include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (═O), and a cyano group.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group, and a methoxy group or an ethoxy group. Is most preferred.
As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.
As the halogenated alkyl group, a part or all of hydrogen atoms of an alkyl group having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a tert-butyl group, etc. And a group substituted with a halogen atom.

Examples of the aliphatic hydrocarbon group include a linear or branched saturated hydrocarbon group, a linear or branched monovalent unsaturated hydrocarbon group, or a cyclic aliphatic hydrocarbon group (aliphatic ring). Formula group) is preferred.
The linear saturated hydrocarbon group (alkyl group) preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group Group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, heicosyl group, docosyl group and the like.
The branched saturated hydrocarbon group (alkyl group) preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

As an unsaturated hydrocarbon group, it is preferable that carbon number is 2-10, 2-5 are preferable, 2-4 are preferable, and 3 is especially preferable. Examples of the linear monovalent unsaturated hydrocarbon group include a vinyl group, a propenyl group (allyl group), and a butynyl group. Examples of the branched monovalent unsaturated hydrocarbon group include a 1-methylpropenyl group and a 2-methylpropenyl group.
Among the above, the unsaturated hydrocarbon group is particularly preferably a propenyl group.

The aliphatic cyclic group may be a monocyclic group or a polycyclic group. The number of carbon atoms is preferably 3 to 30, more preferably 5 to 30, further preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 12.
Specifically, for example, a group in which one or more hydrogen atoms are removed from a monocycloalkane; a group in which one or more hydrogen atoms are removed from a polycycloalkane such as bicycloalkane, tricycloalkane, tetracycloalkane, etc. Can be mentioned. More specifically, a group in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; one or more polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Examples include a group excluding a hydrogen atom.
When the aliphatic cyclic group does not contain a substituent containing a hetero atom in the ring structure, the aliphatic cyclic group is preferably a polycyclic group, and has one or more hydrogen atoms from the polycycloalkane. Excluded groups are preferred, and groups obtained by removing one or more hydrogen atoms from adamantane are most preferred.
When the aliphatic cyclic group includes a substituent containing a hetero atom in the ring structure, examples of the substituent containing a hetero atom include —O—, —C (═O) —O—, —S—. , —S (═O) ₂ — and —S (═O) ₂ —O— are preferable. Specific examples of the aliphatic cyclic group include the following formulas (L1) to (L5), (S1) to (S4), and the like.

［式中、Ｑ”は炭素数１〜５のアルキレン基、−Ｏ−、−Ｓ−、−Ｏ−Ｒ^９４−または−Ｓ−Ｒ^９５−であり、Ｒ^９４およびＲ^９５はそれぞれ独立に炭素数１〜５のアルキレン基であり、ｍは０または１の整数である。］

[Wherein, Q ″ is an alkylene group having 1 to 5 carbon atoms, —O—, —S—, —O—R ⁹⁴ — or —S—R ⁹⁵ —, and R ⁹⁴ and R ⁹⁵ are each independently carbon. An alkylene group of 1 to 5 and m is an integer of 0 or 1.]

As the alkylene group for Q ″, the same alkylene groups as those described above for R ¹ can be used.
As the alkylene group for R ⁹⁴ and R ^95, the same alkylene groups as those described above for R ¹ can be used.
In these aliphatic cyclic groups, a part of hydrogen atoms bonded to carbon atoms constituting the ring structure may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxygen atom (═O).
As said alkyl group, a C1-C5 alkyl group is preferable, and it is especially preferable that they are a methyl group, an ethyl group, a propyl group, n-butyl group, and a tert- butyl group.
Examples of the alkoxy group and the halogen atom are the same as those exemplified as the substituent for substituting part or all of the hydrogen atoms.

In the present invention, X is preferably a cyclic group which may have a substituent. The cyclic group may be an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent. It is preferably an aliphatic cyclic group that may be used.
The aromatic hydrocarbon group is preferably a naphthyl group which may have a substituent or a phenyl group which may have a substituent.
As the aliphatic cyclic group which may have a substituent, a polycyclic aliphatic cyclic group which may have a substituent is preferable. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from the polycycloalkane, the above (L2) to (L5), (S3) to (S4), and the like.

  In addition, since the component (B1) is excellent in the effect of the present invention, the fluorination rate of the anion portion (ratio of the number of fluorine atoms to the total number of fluorine atoms and hydrogen atoms contained in the anion portion (%)) is It is preferably 1 to 95%, more preferably 5 to 90%, and still more preferably 8 to 50%.

In formula (b1), the organic cation of A ⁺ is not particularly limited, and any conventionally known cation part of an onium salt-based acid generator can be appropriately used. As such a cation moiety, a sulfonium ion or an iodonium ion is preferable, and a sulfonium ion is particularly preferable.
Specific examples include a cation moiety represented by the following general formula (I-1) or (I-2).

［式中、Ｒ^１〜Ｒ^３は、それぞれ独立に、置換基を有していてもよいアリール基、または置換基を有していてもよいアルキル基であり、Ｒ^１〜Ｒ^３のうち少なくとも１つは前記アリール基であり、Ｒ^１〜Ｒ^３のうちの２つが相互に結合して式中のイオウ原子と共に環を形成していてもよい。式中、Ｒ^５〜Ｒ^６は、それぞれ独立に、置換基を有していてもよいアリール基、または置換基を有していてもよいアルキル基であり、Ｒ^５”〜Ｒ^６”のうち少なくとも１つは前記アリール基である。］

[Wherein, R ^{1 to} R ³ are each independently an aryl group which may have a substituent, or an alkyl group which may have a substituent, and at least of R ^{1 to} R ³ . One is the aryl group, and two of R ^{1 to} R ³ may be bonded to each other to form a ring together with the sulfur atom in the formula. In the formula, R ^{5 to} R ⁶ are each independently an aryl group which may have a substituent, or an alkyl group which may have a substituent, and among R ⁵ ″ to R ⁶ ″ At least one is the aryl group. ]

In formula (I-1), R ^{1 to} R ³ each independently represents an aryl group or an alkyl group. Any two of R ^{1 to} R ³ may be bonded to each other to form a ring together with the sulfur atom in the formula.
^Further, among R 1 to R ^3, at least one group represents an aryl group. Of R ^{1 to} R ³ , two or more are preferably aryl groups, and most preferably R ^{1 to} R ³ are all aryl groups.

The aryl group for R ^{1 to} R ³ is not particularly limited, and examples thereof include an unsubstituted aryl group having 6 to 20 carbon atoms, and part or all of the hydrogen atoms of the unsubstituted aryl group are alkyl groups and alkoxy groups. , alkoxyalkyl group, an alkoxycarbonylalkyl group, a halogen atom, substituted substituted aryl group such as a hydroxyl group, - (R ⁴ ') include ^{-C (= O) -R 5'} . R ⁴ ′ is an alkylene group having 1 to 5 carbon atoms. R ⁵ ′ is an aryl group. As the aryl group for R ⁵ ′, the same aryl groups as those described above for R ¹ ″ to R ³ ″ can be used.
The unsubstituted aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.

The alkyl group in the substituted aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group in the substituted aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and most preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. preferable.
The halogen atom in the substituted aryl group is preferably a fluorine atom.

Examples of the alkoxyalkyloxy group in the substituted aryl group include, for example, a general formula: —O—C (R ⁴⁷ ) (R ⁴⁸ ) —O—R ⁴⁹ [wherein R ⁴⁷ and R ⁴⁸ are each independently a hydrogen atom or It is a linear or branched alkyl group, and ^R49 is an alkyl group.
In R ⁴⁷ and R ⁴⁸ , the alkyl group preferably has 1 to 5 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group.
At least one of R ⁴⁷ and R ⁴⁸ is preferably a hydrogen atom. In particular, it is more preferable that one is a hydrogen atom and the other is a hydrogen atom or a methyl group.
The alkyl group for R ⁴⁹ preferably has 1 to 15 carbon atoms and may be linear, branched or cyclic.
The linear or branched alkyl group for R ⁴⁹ preferably has 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group. Can be mentioned.
The cyclic alkyl group for R ⁴⁹ preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, a monocycloalkane, bicycloalkane, tricycloalkane, tetracycloalkane, etc., which may or may not be substituted with an alkyl group having 1 to 5 carbon atoms, a fluorine atom or a fluorinated alkyl group, etc. And a group obtained by removing one or more hydrogen atoms from the polycycloalkane. Examples of the monocycloalkane include cyclopentane and cyclohexane. Examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.

Examples of the alkoxycarbonylalkyloxy group in the substituted aryl group include, for example, a general formula: —O—R ⁵⁰ —C (═O) —O—R ⁵¹ [wherein R ⁵⁰ is a linear or branched alkylene group. And R ⁵¹ is a tertiary alkyl group. ] Is represented.
The linear or branched alkylene group for R ⁵⁰ preferably has 1 to 5 carbon atoms, such as a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, or a 1,1-dimethylethylene group. Etc.
As the tertiary alkyl group for R ⁵¹ , 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-methyl-1-cyclopentyl group, 1-ethyl-1-cyclopentyl group, 1-methyl -1-cyclohexyl group, 1-ethyl-1-cyclohexyl group, 1- (1-adamantyl) -1-methylethyl group, 1- (1-adamantyl) -1-methylpropyl group, 1- (1-adamantyl) -1-methylbutyl group, 1- (1-adamantyl) -1-methylpentyl group; 1- (1-cyclopentyl) -1-methylethyl group, 1- (1-cyclopentyl) -1-methylpropyl group, 1- (1-cyclopentyl) -1-methylbutyl group, 1- (1-cyclopentyl) -1-methylpentyl group; 1- (1-cyclohexyl) -1-methylethyl Group, 1- (1-cyclohexyl) -1-methylpropyl group, 1- (1-cyclohexyl) -1-methylbutyl group, 1- (1-cyclohexyl) -1-methylpentyl group, tert-butyl group, tert -Pentyl group, tert-hexyl group and the like.

The aryl groups for R ^{1 to} R ³ are each preferably a phenyl group or a naphthyl group.

The alkyl group of R ¹ to R ^3, is not particularly limited, for example, linear C1-10, branched or cyclic alkyl group, and the like. It is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decanyl group. A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.

When any two of R ^{1 to} R ³ are bonded to each other to form a ring together with the sulfur atom in the formula, it is preferable to form a 3 to 10 membered ring including the sulfur atom, It is particularly preferable that a 7-membered ring is formed.
When any two of R ^{1 to} R ³ are bonded to each other to form a ring together with the sulfur atom in the formula, the remaining one is preferably an aryl group. Examples of the aryl group include the same aryl groups as those described above for R ^{1 to} R ³ .

  Specific examples of the cation moiety represented by the formula (I-1) include, for example, triphenylsulfonium, (3,5-dimethylphenyl) diphenylsulfonium, (4- (2-adamantoxymethyloxy) -3,5 -Dimethylphenyl) diphenylsulfonium, (4- (2-adamantoxymethyloxy) phenyl) diphenylsulfonium, (4- (tert-butoxycarbonylmethyloxy) phenyl) diphenylsulfonium, (4- (tert-butoxycarbonylmethyloxy) -3,5-dimethylphenyl) diphenylsulfonium, (4- (2-methyl-2-adamantyloxycarbonylmethyloxy) phenyl) diphenylsulfonium, (4- (2-methyl-2-adamantyloxycarbonylmethyloxy) -3 , 5- Methylphenyl) diphenylsulfonium, tri (4-methylphenyl) sulfonium, dimethyl (4-hydroxynaphthyl) sulfonium, monophenyldimethylsulfonium, diphenylmonomethylsulfonium, (4-methylphenyl) diphenylsulfonium, (4-methoxyphenyl) diphenylsulfonium , Tri (4-tert-butyl) phenylsulfonium, diphenyl (1- (4-methoxy) naphthyl) sulfonium, di (1-naphthyl) phenylsulfonium, 1-phenyltetrahydrothiophenium, 1- (4-methylphenyl) Tetrahydrothiophenium, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium, 1- (4-methoxynaphthalen-1-yl) tetrahydrothiol 1- (4-ethoxynaphthalen-1-yl) tetrahydrothiophenium, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium, 1-phenyltetrahydrothiopyranium, 1- (4 -Hydroxyphenyl) tetrahydrothiopyranium, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiopyranium, 1- (4-methylphenyl) tetrahydrothiopyranium and the like.

In formula (I-2), R ^{5 to} R ⁶ each independently represents an aryl group or an alkyl group. At least one of R ^{5 to} R ⁶ represents an aryl group. All of R ^{5 to} R ⁶ are preferably aryl groups.
Examples of the aryl group for R ^{5 to} R ⁶ include the same aryl groups as R ^{1 to} R ³ .
Examples of the alkyl group for R ^{5 to} R ⁶ include the same alkyl groups as those for R ^{1 to} R ³ .
Among these, it is most preferable that all of R ^{5 to} R ⁶ are phenyl groups.
Specific examples of the cation moiety represented by the formula (I-2) include diphenyliodonium and bis (4-tert-butylphenyl) iodonium.

  Moreover, as a preferable cation part, the cation part represented by the following general formula (I-5) or (I-6) is mentioned.

［式中、Ｒ^４０は水素原子またはアルキル基であり、Ｒ^４１はアルキル基、アセチル基、カルボキシ基、またはヒドロキシアルキル基であり、Ｒ^４２〜Ｒ^４６はそれぞれ独立してアルキル基、アセチル基、アルコキシ基、カルボキシ基、またはヒドロキシアルキル基であり；ｎ_０〜ｎ_５はそれぞれ独立して０〜３の整数であり、ただし、ｎ_０＋ｎ_１は５以下であり、ｎ_６は０〜２の整数である。］

[Wherein, R ⁴⁰ represents a hydrogen atom or an alkyl group, R ⁴¹ represents an alkyl group, an acetyl group, a carboxy group, or a hydroxyalkyl group, and R ^{42 to} R ⁴⁶ each independently represents an alkyl group, an acetyl group, An alkoxy group, a carboxy group, or a hydroxyalkyl group; n _{0 to} n ₅ are each independently an integer of 0 to 3, provided that n ₀ + n ₁ is 5 or less and n ₆ is 0 to 2 It is an integer. ]

In R ^{40 to} R ⁴⁶ in the general formula (I-5) or (I-6), the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a linear or branched alkyl group. A methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, or a tert-butyl group is particularly preferable.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a linear or branched alkoxy group, and particularly preferably a methoxy group or an ethoxy group.
The hydroxyalkyl group is preferably a group in which one or more hydrogen atoms in the alkyl group are substituted with a hydroxy group, and examples thereof include a hydroxymethyl group, a hydroxyethyl group, and a hydroxypropyl group.
When the sign n ₀ attached to the OR ⁴⁰ is an integer of 2 or more, the plurality of OR ⁴⁰ ″ may be the same or different.
When the symbols n _{1 to} n ₆ attached to R ^{41 to} R ⁴⁶ are integers of 2 or more, the plurality of R ^{41 to} R ⁴⁶ may be the same or different.
n ₀ is preferably 0 or 1.
n ₁ is preferably 0-2.
n ₂ and n ₃ are preferably each independently 0 or 1, more preferably 0.
n ₄ is preferably 0 to 2, more preferably 0 or 1.
n ₅ is preferably 0 or 1, more preferably 0.
n ₆ is preferably 0 or 1.

As A ⁺ , a cation moiety represented by formula (I-1) or (I-5) is preferable, and in particular, the following formulas (I-1-1) to (I-1-10), (I-5) -1) to (I-5-4) are preferred. Especially, the cation part of a triphenyl skeleton, such as the cation part represented by Formula (I-1-1)-(I-1-8), is more preferable.
In formulas (I-1-9) to (I-1-10), R ⁸ and R ⁹ are each independently a phenyl group, naphthyl group or carbon number 1 to 5 which may have a substituent. An alkyl group, an alkoxy group, and a hydroxyl group.
u is an integer of 1 to 3, and 1 or 2 is most preferable.

  In the present invention, the component (B1) is preferably a compound represented by the following general formula (b1-1).

［式中、Ｘ、Ｙ^１およびＡ^＋はそれぞれ前記と同じであり、Ｑ^２は単結合またはアルキレン基であり、ｎは０または１である。］

[Wherein, X, Y ¹ and A ⁺ are the same as defined above, Q ² is a single bond or an alkylene group, and n is 0 or 1. ]

In formula (b1-1), X is preferably an aliphatic cyclic group which may have a substituent or an aromatic hydrocarbon group which may have a substituent. Among these, an aliphatic cyclic group containing a substituent containing a hetero atom in the ring structure is preferable.
As the alkylene group for Q ^2, the same alkylene groups as those described above for Q ¹ can be mentioned.
Q ² is particularly preferably a single bond or a methylene group. Among them, when X is an aliphatic cyclic group which may have a substituent, Q ² is preferably a single bond, and when X is an aromatic hydrocarbon group, Q ² is methylene. It is preferably a group.
n may be 0 or 1. When X is an aliphatic cyclic group which may have a substituent, n is preferably 1, and when X is an aromatic hydrocarbon group, n is preferably 0. .

  As the component (B1), compounds represented by the following general formulas (b1-1-1) to (b1-1-5) are particularly preferable.

［式中、Ｑ”、Ａ^＋はそれぞれ前記と同じであり、ｐは１〜３の整数であり、ｎ１〜ｎ５はそれぞれ独立に０または１であり、ｖ１〜ｖ５はそれぞれ独立に０〜３の整数であり、ｗ１〜ｗ５はそれぞれ独立に０〜３の整数であり、Ｒ^７は置換基である。］

Wherein Q ″ and A ⁺ are the same as defined above, p is an integer of 1 to 3, n1 to n5 are each independently 0 or 1, and v1 to v5 are each independently 0 to 3 W1 to w5 are each independently an integer of 0 to 3, and R ⁷ is a substituent.]

Examples of the substituent for R ⁷ are the same as those described above as the substituent that the aliphatic hydrocarbon group may have and the substituent that the aromatic hydrocarbon group may have in X. Can be mentioned.
Code (r1, w1 to w5) attached to R ⁷ when is an integer of 2 or more, a plurality of the R ⁷ groups may be the same, respectively, it may be different.
As described above, A ⁺ is preferably a sulfonium ion or an iodonium ion, more preferably an anion moiety represented by the general formula (I-1) or (I-5), and the general formula (I-1). The anion moiety represented by is most preferable.

As the component (B1), one type may be used alone, or two or more types may be used in combination.
In the component (B), the proportion of the component (B1) is preferably 10 to 99% by mass, more preferably 30 to 95% by mass, and still more preferably 50 to 90% by mass with respect to the total mass of the component (B). The effect of this invention improves that the ratio of (B1) component exists in the said range.

  The component (B1) can be produced by a conventionally known method. For example, by a production method including a step of reacting a compound (b0-1) represented by the following general formula (b0-1) with a compound (b0-2) represented by the following general formula (b0-2) Can be manufactured.

Wherein ^{(b0-1), X, Q 2} , n, Y 1 are respectively ^X in the formula (b1-1) in, Q 2, n, same as ^{Y 1.}
M ⁺ is an alkali metal ion. Examples of the alkali metal ion include sodium ion, lithium ion, potassium ion and the like, and sodium ion or lithium ion is preferable.
Z ⁻ is a non-nucleophilic ion.
Examples of the non-nucleophilic ion include halogen ions such as bromine ion and chlorine ion, ions that can be acid having lower acidity than the compound (b0-01), BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ^- or ClO ₄ ^- and the like.
Examples of ions that can be an acid having a lower acidity than the compound (b0-01) in Z ⁻ include sulfonate ions such as p-toluenesulfonate ion, methanesulfonate ion, benzenesulfonate ion, and trifluoromethanesulfonate ion. Is mentioned.

As the compound (b0-1) and the compound (b0-2), commercially available compounds may be used, or they may be synthesized by a known method.
Although the manufacturing method of a compound (b0-1) is not specifically limited, For example, the compound represented by the following general formula (b0-1-11) is carried out in solvents, such as tetrahydrofuran and water, sodium hydroxide, lithium hydroxide, etc. To give a compound represented by the following general formula (b0-1-12) in an aqueous solution of an alkali metal hydroxide, and then the compound is converted into an acidic catalyst in an organic solvent such as benzene or dichloroethane. In the presence, by dehydrating condensation with an alcohol represented by the following general formula (b0-1-13), a compound in which n in the general formula (b0-1) is 1 (the following general formula (b0-1 -01)) is obtained.

［式中、Ｒ^２１は炭素数１〜５のアルキル基であり、Ｘ、Ｑ^２、Ｙ^１、Ｍ^＋はそれぞれ式（ｂ０−１）中のＸ、Ｑ^２、Ｙ^１、Ｍ^＋と同じである。］

^{Wherein, R 21} is an alkyl group having 1 to 5 carbon ^{atoms, X, Q 2, Y 1} , M + is ^X, respectively formula (b0-1) ^{in, Q 2, Y 1, M} + same It is. ]

Further, for example, fluorine silver, a compound represented by the following general formula (b0-1-01), and a compound represented by the following general formula (b0-1-02) are mixed in an organic solvent such as anhydrous diglyme. To obtain a compound represented by the following general formula (b0-1-03), and the compound in an organic solvent such as tetrahydrofuran, acetone or methyl ethyl ketone, and an alkali such as sodium hydroxide or lithium hydroxide. By reacting with a metal hydroxide, a compound in which n in the general formula (b0-1) is 0 (a compound represented by the following general formula (b0-1-0)) is obtained.
Examples of the halogen atom for _{X h} in the formula (b0-1-02), bromine atom or a chlorine atom is preferable.

［式中、Ｘ、Ｑ^２、Ｙ^１、Ｍ^＋はそれぞれ式（ｂ０−１）中のＸ、Ｑ^１、Ｙ^１、Ｍ^＋と同じであり、Ｘ_ｈはハロゲン原子である。］

[Wherein, X, Q ² , Y ¹ and M ⁺ are the same as X, Q ¹ , Y ¹ and M ^{+ in} formula (b0-1), respectively, and X _h is a halogen atom. ]

The compound (b0-1) and the compound (b0-2) can be reacted, for example, by dissolving these compounds in a solvent such as water, dichloromethane, acetonitrile, methanol, chloroform, methylene chloride, and stirring. Can do.
The reaction temperature is preferably about 0 ° C to 150 ° C, more preferably about 0 ° C to 100 ° C. The reaction time varies depending on the reactivity of the compound (b0-1) and the compound (b0-2), the reaction temperature, and the like, but usually 0.5 to 10 hours is preferable, and 1 to 5 hours is more preferable.
The amount of compound (b0-2) used in the above reaction is usually preferably about 0.5 to 2 mol per 1 mol of compound (b0-1).

[(B2) component]
In formula (b2), the fluorinated alkyl group for R ⁴ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms. .
The fluorination rate of the fluorinated alkyl group (ratio of the number of fluorine atoms to the total number of fluorine atoms and hydrogen atoms (%)) is preferably 50 to 100%, more preferably 80 to 100%, and more preferably 85 to 100%. Is more preferable. In particular, a fluorinated alkyl group (perfluoroalkyl group) in which all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms is preferable because the strength of the acid generated is increased. In addition, the fluorination rate of the fluorinated alkyl group of R ⁴ corresponds to the fluorination rate of the anion part of the component (B2).
Specific examples of the anion moiety in which R ⁴ is a perfluoroalkyl group include trifluoromethyl sulfonate ion, heptafluoro-n-propyl sulfonate ion, nonafluoro-n-butyl sulfonate ion, and the like.

A ′ ⁺ is not particularly limited, and examples thereof include the same as A ⁺ .
As A ^'+, similar to the A ^+, preferably a sulfonium ion or an iodonium ion, the anion portion is more preferably represented by the general formula (I-1) or (I-5), the general formula (I- The anion moiety represented by 1) is most preferred.

As the component (B2), one type may be used alone, or two or more types may be used in combination.
In the component (B), the ratio of the component (B2) is preferably 1 to 80% by mass, more preferably 2 to 50% by mass, and further preferably 5 to 30% by mass with respect to the total mass of the component (B). The effect of this invention improves that the ratio of (B1) component exists in the said range.

In the component (B), the content ratio (molar ratio) of the component (B1) and the component (B2) is excellent in the effect of the present invention, so the component (B1): component (B2) = 99: 1 to 1 : 99 is preferable, 95: 5 to 10:90 is more preferable, 90:10 to 20:80 is more preferable, and 90:10 to 40:60 is most preferable.
In the component (B), the total amount of the component (B1) and the component (B2) is preferably 50% by mass or more, and 80% by mass or more based on the total mass of the component (B) in consideration of the effect of the present invention. More preferably, it may be 100% by mass.
Moreover, in (B) component, since it is excellent in the effect of this invention, it is preferable that (B1) component and / or (B2) component have an anion part represented by the said general formula (I-1). .

[(B3) component]
The resist composition of the present invention may further contain an acid generator (hereinafter referred to as (B3) component) other than the (B1) component and the (B2) component as the (B) component.
The component (B3) is not particularly limited as long as it does not correspond to the component (B1) and the component (B2), and any known acid generator can be used. Specifically, onium salt acid generators, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, poly (bissulfonyl) diazomethanes, etc. that do not fall under the components (B1) and (B2) above. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators and the like.

  Examples of the onium salt acid generator that does not correspond to the component (B1) and the component (B2) include compounds represented by the following general formula (b-1) or (b-2).

［式中、Ｒ^１”〜Ｒ^３”，Ｒ^５”〜Ｒ^６”は、それぞれ独立に、置換基を有していてもよいアリール基、または置換基を有していてもよいアルキル基であり、式（ｂ−１）中のＲ^１”〜Ｒ^３”のうち少なくとも１つは前記アリール基であり、Ｒ^１”〜Ｒ^３”のうちの２つが相互に結合して式中のイオウ原子と共に環を形成してもよく、式（ｂ−２）中のＲ^５”〜Ｒ^６”は、それぞれ独立に、置換基を有していてもよいアリール基、または置換基を有していてもよいアルキル基であり、Ｒ^５”〜Ｒ^６”のうち少なくとも１つは前記アリール基であり、Ｒ^４”は、直鎖状、分岐鎖状もしくは環状のアルキル基、または分岐鎖状もしくは環状のフッ素化アルキル基である。］

[Wherein, R ¹ ″ to R ³ ″ and R ⁵ ″ to R ⁶ ″ each independently represents an aryl group which may have a substituent, or an alkyl group which may have a substituent. And at least one of R ¹ ″ to R ³ ″ in formula (b-1) is the aryl group, and two of R ¹ ″ to R ³ ″ are bonded to each other to form sulfur in the formula A ring may be formed with an atom, and R ⁵ ″ to R ⁶ ″ in formula (b-2) each independently has an aryl group which may have a substituent, or a substituent. And at least one of R ⁵ ″ to R ⁶ ″ is the aryl group, and R ⁴ ″ is a linear, branched or cyclic alkyl group, or branched or It is a cyclic fluorinated alkyl group.]

In formula (b-1), R ¹ ″ to R ³ ″ are the same as R ^{1 to} R ^{3 in} formula (I-1), respectively.
In formula (b-2), R ⁵ ″ and R ⁶ ″ are the same as R ^{5 to} R ^{6 in} formula (I-2), respectively.
R ⁴ ″ represents a linear, branched or cyclic alkyl group, or a fluorinated alkyl group.
The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. Specific examples include a cyclopentyl group and a cyclohexyl group.
Examples of the fluorinated alkyl group include groups in which some or all of the hydrogen atoms of the branched or cyclic alkyl group are substituted with fluorine atoms among the alkyl groups of R ⁴ ″ described above.
The fluorination rate of the fluorinated alkyl group (ratio of the number of fluorine atoms to the total number of fluorine atoms and hydrogen atoms (%)) is preferably 10 to 100%, more preferably 50 to 100%, particularly alkyl. A fluorinated alkyl group (perfluoroalkyl group) in which all of the hydrogen atoms in the group are substituted with fluorine atoms is preferred because the strength of the acid is increased.
Specific examples of the anion moiety represented by R ⁴ ″ —SO ₃ ^— include methanesulfonate ion, n-propanesulfonate ion, n-butanesulfonate ion, n-octanesulfonate ion, and the like.

  In addition, in the general formula (b-1) or (b-2), an onium salt-based acid generator in which the anion moiety is replaced with an anion moiety represented by the following general formula (b-3) or (b-4). Can also be used (the cation moiety is the same as (b-1) or (b-2)).

［式中、Ｘ”は、少なくとも１つの水素原子がフッ素原子で置換された炭素数２〜６のアルキレン基を表し；Ｙ”、Ｚ”は、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を表す。］

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with

X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, Most preferably, it has 3 carbon atoms.
Y ″ and Z ″ are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 to 10 carbon atoms, Has 1 to 7 carbon atoms, more preferably 1 to 3 carbon atoms.
The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of Y ″ and Z ″ is preferably as small as possible because the solubility in the resist solvent is good within the above carbon number range.
In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, the strength of the acid increases as the number of hydrogen atoms substituted with fluorine atoms increases, and high-energy light or electron beam of 200 nm or less The fluorination rate of the alkylene group or alkyl group is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are fluorine atoms. A substituted perfluoroalkylene group or a perfluoroalkyl group.

  Examples of the oxime sulfonate-based acid generator include compounds having at least one group represented by the following general formula (B-1) and having a property of generating an acid upon irradiation with radiation. Such oxime sulfonate-based acid generators are frequently used for chemically amplified resist compositions, and can be arbitrarily selected and used.

（式（Ｂ−１）中、Ｒ^３１、Ｒ^３２はそれぞれ独立に有機基を表す。）

(In formula (B-1), R ³¹ and R ³² each independently represents an organic group.)

The organic groups of R ³¹ and R ³² are groups containing carbon atoms, and atoms other than carbon atoms (for example, hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), etc.) You may have.
As the organic group for R ^31, a linear, branched, or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.
As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.
The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms or a fluorinated alkyl group having 1 to 4 carbon atoms which has no substituent.

As the organic group for R ^32, a linear, branched, or cyclic alkyl group, aryl group, or cyano group is preferable. As the alkyl group and aryl group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.
R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

［式（Ｂ−２）中、Ｒ^３３は、シアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３４はアリール基である。Ｒ^３５は置換基を有さないアルキル基またはハロゲン化アルキル基である。］

[In Formula (B-2), R ³³ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

［式（Ｂ−３）中、Ｒ^３６はシアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３７は２または３価の芳香族炭化水素基である。Ｒ^３８は置換基を有さないアルキル基またはハロゲン化アルキル基である。ｐ”は２または３である。］

[In Formula (B-3), R ³⁶ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. ^R38 is an alkyl group having no substituent or a halogenated alkyl group. p ″ is 2 or 3.]

In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent of R ³³ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and carbon atoms. Numbers 1 to 6 are most preferable.
R ³³ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³³ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred.

As the aryl group of R ³⁴ , one hydrogen atom is removed from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, or a phenanthryl group. And a heteroaryl group in which a part of carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Among these, a fluorenyl group is preferable.
The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.

The alkyl group or halogenated alkyl group having no substituent for R ³⁵ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.
R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³⁵ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred is the strength of the acid generated. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

In the general formula (B-3), the alkyl group or halogenated alkyl group having no substituent for R ³⁶ is the same as the alkyl group or halogenated alkyl group having no substituent for R ^33. Is mentioned.
Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing one or two hydrogen atoms from the aryl group for R ³⁴ .
Examples of the alkyl group or halogenated alkyl group having no substituent of R ³⁸ include the same alkyl groups or halogenated alkyl groups as those having no substituent of R ³⁵ .
p ″ is preferably 2.

Specific examples of the oxime sulfonate acid generator include α- (p-toluenesulfonyloxyimino) -benzyl cyanide, α- (p-chlorobenzenesulfonyloxyimino) -benzyl cyanide, α- (4-nitrobenzenesulfonyloxy). Imino) -benzylcyanide, α- (4-nitro-2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzylcyanide, α- (benzenesulfonyl) Oxyimino) -2,4-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -2,6-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -4-methoxybenzyl cyanide, α- ( 2-Chlorobenzenesulfonyloxyimino) 4-methoxybenzylcyanide, α- (benzenesulfonyloxyimino) -thien-2-ylacetonitrile, α- (4-dodecylbenzenesulfonyloxyimino) -benzylcyanide, α-[(p-toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α- (tosyloxyimino) -4-thienyl cyanide, α- (methylsulfonyloxyimino) -1-cyclo Pentenyl acetonitrile, α- (methylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -1-cycloheptenylacetonitrile, α- (methylsulfonyloxyimino) -1-cyclooctene Acetonitrile, α- (trifluoromethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -cyclohexylacetonitrile, α- (ethylsulfonyloxyimino) -ethylacetonitrile, α- (propyl Sulfonyloxyimino) -propylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclohexylacetonitrile, α- (cyclohexylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- ( Ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclope N-tenyl acetonitrile, α- (n-butylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclohexenylacetonitrile , Α- (n-butylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoro Methylsulfonyloxyimino) -phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p- Butoxy phenylacetonitrile, alpha-(propylsulfonyl oxyimino)-p-methylphenyl acetonitrile, alpha-like (methylsulfonyloxyimino)-p-bromophenyl acetonitrile.
Further, an oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [Chemical 18] to [Chemical 19]), pamphlet of International Publication No. 04/074242, An oxime sulfonate-based acid generator disclosed in Examples 1 to 40) on pages 65 to 85 can also be suitably used.
Moreover, the following can be illustrated as a suitable thing.

Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, Examples include bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, and the like.
Further, diazomethane acid generators disclosed in JP-A-11-035551, JP-A-11-035552, and JP-A-11-035573 can also be suitably used.
Examples of poly (bissulfonyl) diazomethanes include 1,3-bis (phenylsulfonyldiazomethylsulfonyl) propane and 1,4-bis (phenylsulfonyldiazo) disclosed in JP-A-11-322707. Methylsulfonyl) butane, 1,6-bis (phenylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (phenylsulfonyldiazomethylsulfonyl) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfonyl) ethane, 1,3 -Bis (cyclohexylsulfonyldiazomethylsulfonyl) propane, 1,6-bis (cyclohexylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfonyl) decane, etc. Door can be.

  As the component (B3), one type of acid generator may be used alone, or two or more types may be used in combination.

  Content of (B) component in the resist composition of this invention is 0.5-30 mass parts with respect to 100 mass parts of (A) component, Preferably it is 1-20 mass parts. By setting it within the above range, pattern formation is sufficiently performed. Moreover, since a uniform solution is obtained and storage stability becomes favorable, it is preferable.

<Optional component>
The resist composition of the present invention preferably further contains a nitrogen-containing organic compound (D) (hereinafter referred to as “component (D)”) in order to improve the resist pattern shape, the stability over time and the like.
Since a wide variety of component (D) has already been proposed, any known one can be used. Among them, aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are used. preferable. An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms.
Examples of the aliphatic amine include an amine (alkyl amine or alkyl alcohol amine) or a cyclic amine in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms.
Specific examples of alkylamines and alkyl alcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di- -Dialkylamines such as n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine , Tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, tri-n-dodecylamine, and the like; diethanolamine, triethanolamine, diisopropanolamine Triisopropanolamine, di -n- octanol amines, alkyl alcohol amines tri -n- octanol amine.
Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable. Specifically, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5. 4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane, and the like.

  Further, as the component (D) preferably used in the present invention, a nitrogen-containing organic compound (D1) (hereinafter referred to as the component (D1)) represented by the following general formula (d1) and having a molecular weight of 200 or more. Can be mentioned.

［式（ｄ１）中、Ｒ^８１〜Ｒ^８３はそれぞれ独立して置換基を有していてもよい炭化水素基であって、Ｒ^８１〜Ｒ^８３のうち少なくとも１つが極性基含有炭化水素基であり、かつ、Ｒ^８１〜Ｒ^８３のうち少なくとも１つが疎水基である。ただし、Ｒ^８１〜Ｒ^８３のいずれか２つが相互に結合して式中の窒素原子と共に環を形成してもよい。］

[In the formula (d1), R ^{81 to} R ⁸³ are each independently a hydrocarbon group which may have a substituent, and at least one of R ^{81 to} R ⁸³ is a polar group-containing hydrocarbon group. And at least one of R ^{81 to} R ⁸³ is a hydrophobic group. However, any two of R ^{81 to} R ⁸³ may be bonded to each other to form a ring together with the nitrogen atom in the formula. ]

The molecular weight of the component (D1) is 200 or more, preferably 220 or more, and more preferably 300 or more. When the molecular weight of the component (D1) is 200 or more, a resist pattern having a good shape is easily formed.
The upper limit is preferably 1000 or less, more preferably 800 or less, and even more preferably 700 or less. When the molecular weight is 1000 or less, solubility in a resist solvent (such as an organic solvent (S) described later) is improved.

In the formula (d1), R ^{81 to} R ⁸³ are each independently a hydrocarbon group which may have a substituent, and at least one of R ^{81 to} R ⁸³ is a polar group-containing hydrocarbon group. And at least one of R ^{81 to} R ⁸³ is a hydrophobic group.

In the hydrocarbon group which may have a substituent, the hydrocarbon group “has a substituent” means that part or all of the hydrogen atoms in the hydrocarbon group are substituted with groups or atoms other than hydrogen atoms. Means that
The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity.
Examples of the substituent include a halogen atom, a halogenated lower alkyl group having 1 to 5 carbon atoms substituted with a halogen atom, a polar group, or a group containing a polar group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with halogen atoms, with fluorinated alkyl groups being particularly preferred.

In the polar group or the group containing a polar group, preferred specific examples of the polar group include an ether group (—O—), an ester group, a hydroxy group (—OH), and a carbonyl group (—C (═O) — ), A carboxy group (—COOH), an oxygen atom (═O), a cyano group (—CN), a lactone ring, an amino group (—NH ₂ ), and an amide group (—NHC (═O) —).
A group containing a polar group (hereinafter referred to as polar group-containing substituent) refers to a group or atom containing a polar group in its structure.
For example, the component (D1) includes a compound containing a moiety represented by the following formula.

  Examples of the polar group-containing substituent include an alkyloxy group, a hydroxyalkyloxy group, an alkyloxyalkyloxy group, an alkyloxycarbonyloxy group, an alkoxycarbonylalkyloxy group, and an alkyloxycarbonyl group.

The aliphatic hydrocarbon group for R ^{81 to} R ⁸³ may be saturated or unsaturated, and is usually preferably saturated.
1-50 are preferable, as for carbon number of an aliphatic hydrocarbon group, it is more preferable that it is 2-50, and it is further more preferable that it is 3-50.
Examples of the aliphatic hydrocarbon group include a linear, branched or cyclic monovalent saturated hydrocarbon group; a linear or branched monovalent aliphatic unsaturated hydrocarbon group.
Specific examples of these aliphatic hydrocarbon groups include, for example, the same groups as those described above for the hydrocarbon group for X.

Examples of the aromatic hydrocarbon group for R ^{81 to} R ⁸³ include the same aromatic hydrocarbon groups as those described above for X as the aromatic hydrocarbon group.

In the formula (d1), at least one of R ^{81 to} R ⁸³ is a polar group-containing hydrocarbon group, and at least one of R ^{81 to} R ⁸³ is a hydrophobic group.
In the polar group-containing hydrocarbon group, the polar group may be present at any position in the hydrocarbon group. For example, the polar group may be present at the end of the hydrocarbon group, and hydrogen in the middle of the hydrocarbon chain. A part of the atoms may be substituted and may be present in the middle of the hydrocarbon group, or may be present as a linking group between the carbon atoms constituting the hydrocarbon chain of the hydrocarbon group. Examples of the linking group include an ether group (—O—), an ester group, a carbonyl group (—C (═O) —), an amide group (—NHC (═O) —), and the like.
Further, the polar group present in the hydrocarbon group may be one or plural, and preferably one is present.
Examples of the polar group-containing hydrocarbon group include those in which the terminal of the aliphatic hydrocarbon group or the aromatic hydrocarbon group or a hydrogen atom in the middle thereof is substituted by the polar group or the polar group-containing substituent; And the like in which the polar group is present as a linking group in the middle of the hydrocarbon chain of the aliphatic hydrocarbon group.

  Examples of the hydrophobic group include, for example, the above aliphatic hydrocarbon group, aromatic hydrocarbon group, aliphatic hydrocarbon group to which a halogen atom or a halogenated lower alkyl group is bonded, and aromatic to which a halogen atom or a halogenated lower alkyl group is bonded. Group hydrocarbon group.

In the formula (d1), any two of R ^{81 to} R ⁸³ may be bonded to each other to form a ring together with the nitrogen atom in the formula. In this case, a cyclic group is formed by any two of R ^{1 to} R ³ and the nitrogen atom in the formula.
In such a case, the polar group-containing hydrocarbon group may constitute part or all of the cyclic group, in which case the polar group or polar group-containing substituent forms part of the main chain of the ring. It may be bonded to a carbon atom constituting the ring as a substituent.
As the cyclic group, a 4- to 7-membered ring including a nitrogen atom in the formula is preferable, and a 4- to 6-membered ring is more preferable.
For example, the component (D1) includes a compound containing a moiety represented by the following formula.

Among these, as the component (D1), since the effect of the present invention is better, two of R ^{1 to} R ³ in the general formula (d1) are polar group-containing hydrocarbon groups. In addition, a nitrogen-containing organic compound (D1-1) (hereinafter referred to as the component (D1-1)) in which the remaining one is a hydrophobic group is preferable.
Among those contained in the component (D1-1), a nitrogen-containing organic compound represented by the following general formula (d1-1-0) is most preferable because the effect of the present invention is particularly good.

［式（ｄ１−１−０）中、Ｒ^８４は置換基を有していてもよい炭素数５〜５０のアルキル基であり、Ｒ^８５およびＲ^８６はそれぞれ独立して置換基を有していてもよい炭素数１〜３０のアルキレン基である。］

[In the formula (d1-1-0), R ⁸⁴ is an optionally substituted alkyl group having 5 to 50 carbon atoms, and R ⁸⁵ and R ⁸⁶ each independently have a substituent. The alkylene group may have 1 to 30 carbon atoms. ]

In formula (d1-1-0), R ⁸⁴ represents an alkyl group having 5 to 50 carbon atoms which may have a substituent.
Examples of the substituent include the same substituents exemplified in the description of R ^{81 to} R ⁸³ .
In the alkyl group of R ^84, preferably from 5 to 50 carbon atoms, more preferably 5 to 45 carbon atoms, more preferably 5 to 40 carbon atoms, is 10 to 20 carbon atoms It is particularly preferable that the number of carbon atoms is 15-20. When the number is 5 or more, the resolution is improved, and when the number is 50 or less, the solubility in a resist solvent (such as an organic solvent (S) described later) is improved.

In formula (d1-1-0), R ⁸⁵ and R ⁸⁶ each independently represent an alkylene group having 1 to 30 carbon atoms which may have a substituent.
Examples of the substituent include the same substituents exemplified in the description of R ^{81 to} R ⁸³ .
The alkylene groups for R ⁸⁵ and R ⁸⁶ each independently preferably have 1 to 30 carbon atoms, more preferably 1 to 25 carbon atoms, and even more preferably 1 to 20 carbon atoms. When the number is 1 or more, the resolution and roundness are improved, and when the number is 30 or less, the solubility in a resist solvent (such as an organic solvent (S) described later) is improved.

  Specific examples suitable as the component (D1) are shown below.

These (D) components may be used independently and may be used in combination of 2 or more type.
(D) component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

The resist composition of the present invention comprises, as optional components, an organic carboxylic acid, a phosphorus oxo acid, and derivatives thereof for the purpose of preventing sensitivity deterioration and improving the resist pattern shape, retention stability over time, and the like. At least one compound (E) selected from the group (hereinafter referred to as component (E)) can be contained.
As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Examples of phosphorus oxo acids and derivatives thereof include phosphoric acid, phosphonic acid, phosphinic acid and the like, and among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include esters in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of phosphinic acid derivatives include phosphinic acid esters such as phenylphosphinic acid.
(E) A component may be used individually by 1 type and may use 2 or more types together.
As the component (E), an organic carboxylic acid is preferable, and salicylic acid is particularly preferable.
(E) A component is used in the ratio of 0.01-5.0 mass parts per 100 mass parts of (A) component.

  The resist composition of the present invention may further contain, if desired, miscible additives such as an additional resin for improving the performance of the resist film, a surfactant for improving coatability, a dissolution inhibitor, Plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like can be added and contained as appropriate.

The resist composition of the present invention can be produced by dissolving the material in an organic solvent (S) (hereinafter sometimes referred to as (S) component).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution. Conventionally, any one of known solvents for chemically amplified resists can be used. Two or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; many such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol Monohydric alcohols: compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate or dipropylene glycol monoacetate, monomethyl ether, monoethyl of the polyhydric alcohols or the compound having an ester bond Ether alkyl such as ether, monopropyl ether, monobutyl ether or monophenyl ether Derivatives of polyhydric alcohols such as compounds having a propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME) among these]; cyclic ethers such as dioxane, methyl lactate, Esters such as ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, Aromatic organics such as dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene A solvent etc. can be mentioned.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
More specifically, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3.
In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
(S) The usage-amount of a component is not specifically limited, It is a density | concentration which can be apply | coated to a board | substrate etc., and is suitably set according to a coating film thickness. Generally, it is used so that the solid content concentration of the resist composition is in the range of 2 to 20 mass%, preferably 5 to 15 mass%.

≪Resist pattern formation method≫
The resist pattern forming method of the present invention includes a step of forming a resist film on a support using the resist composition, a step of exposing the resist film, and a step of developing the resist film to form a resist pattern. including.
The resist pattern forming method of the present invention can be performed, for example, as follows.
That is, first, the resist composition is applied onto a support with a spinner or the like, and pre-baked (post-apply bake (PAB)) for 40 to 120 seconds, preferably 60 to 90 seconds under a temperature condition of 80 to 150 ° C. Then, after selectively exposing ArF excimer laser light through a desired mask pattern, for example, with an ArF exposure apparatus or the like, PEB (post-exposure heating) is performed for 40 to 120 seconds under a temperature condition of 80 to 150 ° C. Preferably, it is applied for 60 to 90 seconds. Subsequently, this is developed using an alkali developer, for example, an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH), preferably rinsed with pure water and dried. In some cases, a baking process (post-bake) may be performed after the development process. In this way, a resist pattern faithful to the mask pattern can be obtained.

The support is not particularly limited, and a conventionally known one can be used, and examples thereof include a substrate for electronic components and a substrate on which a predetermined wiring pattern is formed. More specifically, a silicon substrate, a metal substrate such as copper, chromium, iron, and aluminum, a glass substrate, and the like can be given. As a material for the wiring pattern, for example, copper, aluminum, nickel, gold or the like can be used.
Further, the support may be a substrate in which an inorganic and / or organic film is provided on the above-described substrate. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include an organic antireflection film (organic BARC).

The wavelength used for the exposure is not particularly limited, and ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. Can be done using radiation. The resist composition is effective for KrF excimer laser, ArF excimer laser, EB or EUV, particularly ArF excimer laser.

The exposure of the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or may be immersion exposure.
In immersion exposure, as described above, the portion between the lens, which has been filled with an inert gas such as air or nitrogen, and the resist film on the wafer at the time of exposure is refracted larger than the refractive index of air. The exposure is performed in a state filled with a solvent having a high rate (immersion medium).
More specifically, the immersion exposure is a solvent (immersion medium) having a refractive index larger than the refractive index of air between the resist film obtained as described above and the lowermost lens of the exposure apparatus. And in this state, exposure (immersion exposure) is performed through a desired mask pattern.
As the immersion medium, a solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film exposed by the immersion exposure is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.
Examples of the solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent.
Specific examples of the fluorinated inert liquid include fluorinated compounds such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as main components. Examples thereof include liquids, and those having a boiling point of 70 to 180 ° C are preferable, and those having a boiling point of 80 to 160 ° C are more preferable. It is preferable that the fluorine-based inert liquid has a boiling point in the above range since the medium used for immersion can be removed by a simple method after the exposure is completed.
As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.
More specifically, examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point 102 ° C.). Examples of the perfluoroalkylamine compound include perfluorotributylamine ( Boiling point of 174 ° C.).

According to the resist composition and resist pattern forming method of the present invention, a resist pattern with reduced defects can be formed.
The reason why the above effect is obtained is not clear, but the following may be considered. That is, first, the component (B1) has a substituent containing an oxygen atom in the anion portion, and has a higher polarity than the anion portion of a conventional acid generator such as nonafluorobutanesulfonate, and is sterically. It has a bulky bulky structure. Therefore, when forming a resist film using the said resist composition, it is estimated that (B1) component distributes comparatively uniformly in a resist film. Then, when an acid is generated from the component (B1) by exposure, the resist film has a higher concentration than the anion portion of a conventional acid generator such as nonafluorobutanesulfonate due to the high polarity of the anion portion and the bulky three-dimensional structure. It is presumed that the diffusion of the anion part (acid) in the above is suppressed both chemically and physically. Therefore, in the resist film, the diffusion of the acid generated in the exposed area to the unexposed area is suppressed. As a result, the difference in solubility (dissolution contrast) in the alkaline developer between the unexposed area and the exposed area is improved. Lithographic properties such as resolution are improved.
On the other hand, since the component (B2) has a small anion portion and a relatively high fluorine content, it is relatively distributed on the surface of the resist film, thereby improving the density of the component (B) on the resist film surface. Guessed. Therefore, when the resist film is exposed, an acid is generated not only on the exposed portion but also on the surface of the unexposed resist film, and the properties of the resist film surface change. For example, in the case of the positive type, part of the acid dissociable, dissolution inhibiting group of component (A) is dissociated even in the resist film surface part of the unexposed part, and a hydrophilic group such as a carboxy group is generated, and the hydrophilicity of the resist film surface is increased. improves. As a result, deposits (components having low hydrophilicity) deposited by development, water rinsing and the like are less likely to adhere to the surface, and defects are reduced.
In the present invention, it is presumed that a good resist pattern with reduced defects is formed by the synergistic action of the component (B1) and the component (B2).

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.
[Synthesis Example 1]
(I) 343.6 g of 30% aqueous sodium hydroxide solution was added dropwise to 150 g of methyl fluorosulfonyl (difluoro) acetate and 375 g of pure water while keeping the temperature at 10 ° C. or lower in an ice bath. After dropping, the mixture was refluxed at 100 ° C. for 3 hours, cooled and neutralized with concentrated hydrochloric acid. The obtained solution was added dropwise to 8888 g of acetone, and the precipitate was filtered and dried to obtain 184.5 g of compound (I) as a white solid (purity: 88.9%, yield: 95.5%). .

  (Ii) 56.2 g of compound (I) and 562.2 g of acetonitrile were charged, 77.4 g of p-toluenesulfonic acid monohydrate was added, and the mixture was refluxed at 110 ° C. for 3 hours. Then, it filtered and the filtrate was concentrated and dried. To the obtained solid, 900 g of t-butyl methyl ether was added and stirred. Then, it filtered and the filtrate was dried, and 22.2 g (purity: 91.0%, yield: 44.9%) of compound (II) was obtained as a white solid.

  (Iii) 17.7 g of compound (II) (purity: 91.0%), 13 g of compound (II ′) represented by the following formula (II ′), and 88.3 g of toluene were charged, and p-toluenesulfonic acid monohydrate 5.85 g of the Japanese product was added and refluxed at 130 ° C. for 26 hours. Thereafter, the mixture was filtered, and 279.9 g of methyl ethyl ketone was added to the residue and stirred. Thereafter, the mixture was filtered, and 84.0 g of methanol was added and stirred. Filtration was performed again, and the filtrate was dried to obtain 20.2 g of compound (III) (purity: 99.9%, yield: 72.1%) as a white solid.

  (Iv) 15.0 g (purity: 99.9%) of the compound (III) obtained in (iii) was dissolved in 66.4 g of pure water. To this solution was added 4-methyltriphenylsulfonium bromide 13.3 dissolved in 132.8 g of dichloromethane, and the mixture was stirred at room temperature for 3 hours, and then the organic phase was separated and taken out. Further, the organic phase was washed with 66.4 g of pure water, and the organic phase was concentrated and dried to obtain 20.2 g (yield: 88.1%) of the target compound (VI) as a colorless viscous liquid.

The compound (VI) was analyzed by NMR. The results are shown below.
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.86-7.58 (m, 14H, Ha + Hb), 5.48 (m, 1H, Hd), 4.98 (s, 1H, He ) 4.73 to 4.58 (d, 2H, Hf), 2.71 (m, 1H, Hg), 2.43 (m, 3H, Hc), 2.12 (m, 2H, Hf).
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 106.9.
From the results shown above, it was confirmed that the compound (VI) had a structure shown below.

[Synthesis Example 2]
An aqueous solution in which 16.7 ml of tetrahydrofuran was added to 5.0 g of 2-naphthylmethyloxytetrafluoroethanesulfonyl fluoride, and 0.98 g of lithium hydroxide was dissolved in 13.6 ml of pure water in an ice bath. Was dripped. Then, it stirred in the ice bath. It was confirmed that all of the sulfonyl fluoride groups were converted to lithium sulfonate due to the absence of ¹⁹ F-NMR absorption at −217.6 ppm by —SO ₂ F. Thereafter, the reaction solution was concentrated and dried to obtain a white viscous solid. The obtained crude product was dissolved in 14.2 ml of acetone, filtered to remove LiF as a by-product, and the filtrate was concentrated to obtain 5.50 g of a precursor compound (X).

  Next, 6.99 g of triphenylsulfonium bromide was dissolved in 125 ml of pure water, and 5.50 g of the precursor compound (X) was added to the solution. After stirring at room temperature for 19 hours, 125 g of dichloromethane was added. The organic phase was separated and removed. Further, the organic phase was washed with 40 ml of pure water and then separated to take out the organic phase. The extracted organic phase was concentrated and dried to obtain 7.09 g of the target compound (XI) (yield: 75.2%).

Compound (XI) was analyzed by NMR.
¹ H-NMR (acetone-d6, 400 MHz): δ (ppm) = 8.01 to 7.47 (m, 22H, H ^a ), 5.23 (s, 2H, H ^b ).
¹⁹ F-NMR (acetone-d6, 376 MHz): δ (ppm) = 79.2, 111.8.
From the results shown above, it was confirmed that the compound (XI) had a structure shown below.

(Examples 1-6, Comparative Examples 1-2)
Each component shown in Table 1 was mixed and dissolved to prepare a positive resist composition.

In Table 1, each abbreviation indicates the following, and the numerical value in [] is the blending amount (part by mass).
(A) -1: Mw = 10,000, Mw / Mn = 2 represented by the following structural formula (A) -1 (wherein 1 / m / n = 40/40/20 (molar ratio)) 0.0 copolymer.
(A) -2: Mw = 10,000, Mw / Mn = 1 represented by the following structural formula (A) -2 (wherein 1 / m / n = 40/40/20 (molar ratio)) A copolymer of .7.
(A) -3: Mw = 10000, Mw / Mn = 2.0 represented by the following structural formula (A) -3 (wherein 1 / m / n = 40/40/20 (molar ratio)) Copolymer.
(B1) -1: a compound represented by the following formula (B1) -1 (the compound (VI)).
(B1) -2: a compound represented by the following formula (B1) -2 (the compound (XI)).
(B2) -1: a compound represented by the following formula (B2) -1.
(B2) -2: A compound represented by the following formula (B2) -2.
(D) -1: Stearyl diethanolamine.
(D) -2: tri-n-pentylamine.
(S) -1: Mixed solvent of PGMEA / PGME = 6: 4.

The lithography characteristics of the obtained resist composition were evaluated by the following procedure.
[Defect evaluation]
An organic antireflection film composition “ARC29A” (trade name, manufactured by Brewer Science Co., Ltd.) is applied onto an 8-inch silicon wafer using a spinner, and baked at 205 ° C. for 60 seconds on a hot plate and dried. Thus, an organic antireflection film having a film thickness of 82 nm was formed. Then, each of the resist compositions is applied onto the antireflection film using a spinner, prebaked (PAB) on a hot plate at 110 ° C. for 60 seconds, and dried to obtain a film thickness. A 120 nm resist film was formed.
Next, an ArF excimer laser (193 nm) is applied to the resist film with an ArF exposure apparatus NSR-S308F (Nikon Corp .; NA (numerical aperture) = 0.92) to form a mask pattern (6% halftone mask). Selectively irradiated. Then, a post-exposure heating (PEB) treatment was performed at 110 ° C. for 60 seconds, and a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution NMD-W (manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23 ° C. The film was developed under conditions of 30 seconds, rinsed with pure water for 30 seconds, and then shaken and dried to form a contact hole pattern (hereinafter referred to as C / H pattern) having a diameter of 100 nm and a pitch of 220 nm. .
Next, the surface of the resist pattern was observed using a surface defect observation apparatus KLA2371 (product name) manufactured by KLA Tencor, and the number of reattachment mode defects (pieces) on the surface was determined. The results are also shown in Table 1.
As apparent from the above results, in the examples using the resist compositions of Examples 1 to 6, the number of defects was significantly smaller than those of Comparative Examples 1 and 2.

Claims (8)

A resist composition containing a base material component (A) whose solubility in an alkaline developer is changed by the action of an acid, and an acid generator component (B) that generates an acid upon exposure,
The acid generator component (B) contains a compound (B1) represented by the following general formula (b1) and a compound (B2) represented by the following general formula (b2). Composition.

[Wherein, Q ¹ is a divalent linking group containing an oxygen atom, and Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms or an optionally substituted carbon. A fluorinated alkylene group having 1 to 4 carbon atoms, X is an optionally substituted hydrocarbon group having 3 to 30 carbon atoms, and A ⁺ is an organic cation. ]

[Wherein R ⁴ is a linear fluorinated alkyl group, and A ′ ⁺ is an organic cation. ] 2. The resist composition according to claim 1, wherein A ⁺ in the general formula (b1) and / or A ′ ⁺ in the general formula (b2) is represented by the following general formula (I-1).

[Wherein, R ^{1 to} R ³ are each independently an aryl group which may have a substituent, or an alkyl group which may have a substituent, and at least of R ^{1 to} R ³ . One is the aryl group, and two of R ^{1 to} R ³ may be bonded to each other to form a ring together with the sulfur atom in the formula. ]   The resist composition according to claim 1, wherein the base material component (A) is a base material component whose solubility in an alkaline developer is increased by the action of an acid.   The base material component (A) contains a resin component (A1) whose solubility in an alkaline developer is increased by the action of an acid, and the resin component (A1) contains an acid dissociable, dissolution inhibiting group. The resist composition according to claim 3, comprising a structural unit (a1) derived from   The resist composition according to claim 4, wherein the resin component (A1) further has a structural unit (a2) derived from an acrylate ester containing a lactone-containing cyclic group.   The resist composition according to claim 4 or 5, wherein the resin component (A1) further has a structural unit (a3) derived from an acrylate ester containing a polar group-containing aliphatic hydrocarbon group.   The resist composition as described in any one of Claims 1-6 containing a nitrogen-containing organic compound (D).   A step of forming a resist film using the resist composition according to any one of claims 1 to 7, a step of exposing the resist film, and an alkali development of the resist film to form a resist pattern on a support A resist pattern forming method including a step of forming a film.