JP5376847B2 - Resist composition, resist pattern forming method, novel compound and acid generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a resist pattern forming method using the resist composition. <P>SOLUTION: The resist composition contains 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) contains an acid generator (B1) comprising a compound represented by a general formula (b1-1) wherein Y<SP>11</SP>is 1-4C fluorinated alkyl; Y<SP>12</SP>is 1-4C fluorinated alkylene; Y<SP>13</SP>is a single bond or a divalent linking group, X<SP>10</SP>is a 3-30C cyclic hydrocarbon group, and A<SP>+</SP>is an organic cation. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a resist composition, a method for forming a resist pattern using the resist composition, a novel compound useful as an acid generator for the resist composition, and an acid generator.

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 light 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 been rapidly progressing 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 such requirements, a chemically amplified resist containing a base resin whose solubility in an alkaline developer is changed by the action of an acid and an acid generator that generates an acid upon exposure is used. For example, a positive chemically amplified resist contains, as a base resin, a resin that increases solubility in an alkaline developer by the action of an acid and an acid generator. When the acid is generated, the exposed portion becomes soluble in the alkaline developer.

Up to now, as a base resin for chemically amplified resist, polyhydroxystyrene (PHS) having high transparency with respect to KrF excimer laser (248 nm) and a resin whose hydroxyl group is protected with an acid dissociable, dissolution inhibiting group (PHS resin) Has been used. However, since the PHS resin has an aromatic ring such as a benzene ring, the transparency to light having a wavelength shorter than 248 nm, for example, 193 nm, is not sufficient. For this reason, a chemically amplified resist having a PHS resin as a base resin component has drawbacks such as low resolution in a process using 193 nm light, for example. Therefore, as a resist base resin currently used in ArF excimer laser lithography and the like, it has a structural unit generally derived from a (meth) acrylic acid ester in the main chain because it is excellent in transparency near 193 nm. Resin (acrylic resin) is used. In the case of the positive type, such a resin includes a structural unit derived from a (meth) acrylic acid ester containing a tertiary alkyl ester type acid dissociable, dissolution inhibiting group containing an aliphatic polycyclic group, for example, 2-alkyl. Resins having structural units derived from 2-adamantyl (meth) acrylate or the like are mainly used (see, for example, Patent Document 1).
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.

On the other hand, various acid generators used in chemically amplified resists have been proposed so far, such as onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, Diazomethane 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. As the anion part of the onium salt-based acid generator, 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 a fluorine atom is used (for example, patents). Reference 2).
JP 2003-241385 A JP 2005-037888 A

Among the anion moieties of the onium salt acid generators as described above, perfluoroalkylsulfonic acid ions are generally used at present.
It is considered that a longer perfluoroalkyl chain of such an anion is preferable in order to suppress acid diffusion after exposure. However, perfluoroalkyl chains having 6 to 10 carbon atoms are hardly decomposable, and nonafluorobutanesulfonic acid ions or the like are used for improving handling properties considering bioaccumulation. Therefore, there is a need for new compounds that are more useful as acid generators for resist compositions.
Further, in recent years, the miniaturization of resist patterns has further progressed, and in conventional resist compositions containing an acid generator having perfluoroalkylsulfonic acid ions in the anion portion, it is difficult to obtain desired lithography characteristics, There is a need for further improvements in lithography properties.
The present invention has been made in view of the above circumstances, and is a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, and a resist composition containing the acid generator It is an object to provide an object and a resist pattern forming method using the same.

  In order to solve the above problems, 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 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) is a resist composition containing an acid generator (B1) composed of a compound represented by the following general formula (b1-1).

［式中、Ｙ^１１は置換基を有していてもよい炭素数１〜４のフッ素化アルキル基であり、Ｙ^１２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、Ｙ^１３は酸素原子、エステル結合、アミド結合、カルボニル基、カーボネート結合からなる群から選択される非炭化水素系の酸素原子含有連結基、該非炭化水素系の酸素原子含有連結基とアルキレン基との組み合わせ（ただし、該アルキレン基はＸ ^１０ 側に位置する。）又は単結合であり、Ｘ^１０は置換基を有していてもよい炭素数３〜３０の環状の炭化水素基であり；Ａ^＋は有機カチオンである。］

[Wherein Y ¹¹ is an optionally substituted fluorinated alkyl group having 1 to 4 carbon atoms, and Y ¹² is an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. Y ¹³ is a non-hydrocarbon oxygen atom-containing linking group selected from the group consisting of an oxygen atom, an ester bond, an amide bond, a carbonyl group, and a carbonate bond, and the non-hydrocarbon oxygen atom-containing linking group; A combination with an alkylene group (provided that the alkylene group is located on the X ¹⁰ side) or a single bond , and X ¹⁰ is a cyclic hydrocarbon group having 3 to 30 carbon atoms which may have a substituent. Yes; 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.

  A third aspect of the present invention is a compound represented by the following general formula (b1-1).

［式中、Ｙ^１１は置換基を有していてもよい炭素数１〜４のフッ素化アルキル基であり、Ｙ^１２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、Ｙ^１３は酸素原子、エステル結合、アミド結合、カルボニル基、カーボネート結合からなる群から選択される非炭化水素系の酸素原子含有連結基、該非炭化水素系の酸素原子含有連結基とアルキレン基との組み合わせ（ただし、該アルキレン基はＸ ^１０ 側に位置する。）又は単結合であり、Ｘ^１０は置換基を有していてもよい炭素数３〜３０の環状の炭化水素基であり；Ａ^＋は有機カチオンである。］

[Wherein Y ¹¹ is an optionally substituted fluorinated alkyl group having 1 to 4 carbon atoms, and Y ¹² is an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. Y ¹³ is a non-hydrocarbon oxygen atom-containing linking group selected from the group consisting of an oxygen atom, an ester bond, an amide bond, a carbonyl group, and a carbonate bond, and the non-hydrocarbon oxygen atom-containing linking group; A combination with an alkylene group (provided that the alkylene group is located on the X ¹⁰ side) or a single bond , and X ¹⁰ is a cyclic hydrocarbon group having 3 to 30 carbon atoms which may have a substituent. Yes; A ⁺ is an organic cation. ]

  A fourth aspect of the present invention is an acid generator comprising the compound of the third aspect.

In the present specification and claims, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups unless otherwise specified.
Further, the “alkylene group” includes linear, branched and cyclic divalent saturated hydrocarbon groups unless otherwise specified.
The “lower alkyl group” is an alkyl group having 1 to 5 carbon atoms.
The “halogenated alkyl group” is a group in which part or all of the hydrogen atoms of the alkyl group are substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
“Fluorinated alkyl group” or “fluorinated alkylene group” refers to a group in which part or all of the hydrogen atoms of an alkyl group or alkylene group are substituted with fluorine atoms.
“Structural unit” means a monomer unit (monomer unit) constituting a polymer compound (polymer, copolymer).
“Exposure” is a concept including general irradiation of radiation.

  The present invention provides a novel compound useful as an acid generator for a resist composition, an acid generator using the compound, a resist composition containing the acid generator, and a resist pattern forming method using the compound. it can.

≪Resist composition≫
The resist composition according to the first aspect of the present invention comprises a base component (A) (hereinafter referred to as “component (A)”) whose solubility in an alkaline developer is changed by the action of an acid, and an acid upon exposure. Contains the generated acid generator component (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 alkali developer changes, the solubility of the unexposed portion in the alkali developer does not change. However, in the case of the negative type, the unexposed portion is dissolved and removed to form a resist pattern.
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 material components for chemically amplified resists can be used singly 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 includes a low molecular weight organic compound having a molecular weight of 500 or more and less than 2000 (hereinafter referred to as “low molecular compound”) and a high molecular weight resin having a molecular weight of 2000 or more (polymer material). Broadly divided. 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 alkali developer is used as the component (A), and the negative resist composition further includes a crosslinking agent. Blended.
In such a negative resist composition, when an acid is generated from the component (B) by exposure, the acid acts to cause crosslinking between the base material component and the crosslinking agent, resulting in poor solubility in an alkali developer. To do. Therefore, in the formation of a resist pattern, when a resist film obtained by applying the negative resist composition on a support is selectively exposed, the exposed portion turns into poorly soluble in an alkali developer, while Since the exposed 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 “alkali-soluble resin”) is usually used.
Examples of the alkali-soluble resin include 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, and JP-A-2005-336442. Alternatively, a resin having a fluorinated alcohol disclosed in JP-A-2006-259582 is preferable because it can form a good resist pattern with little swelling. 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”, the component (A) is a base material component (hereinafter referred to as “(A ′) 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 support is selectively exposed, the exposed portion becomes insoluble 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 ((A ′) 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 sometimes 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 component (A2) (hereinafter sometimes referred to as “component (A2)”) whose solubility in an alkali developer increases, or a mixture thereof.

[(A1) component]
As the component (A1), resin components (base resins) that are usually used as base components for chemically amplified resists can be used singly or in combination of two or more.
In the present invention, the component (A1) preferably has 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 those in which a hydrogen atom is bonded to the carbon atom at the α-position, and those in which a substituent (atom or group other than a hydrogen atom) is bonded to the carbon atom in the α-position. 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 some or all of the hydrogen atoms of 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.

In the resist composition of the present invention, it is particularly preferable that the component (A1) 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 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 a structural unit (a3).

Structural Unit (a1) The structural unit (a1) is a structural unit derived from an acrylate ester containing an acid dissociable, dissolution inhibiting group.
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, in the present specification and claims, “aliphatic” is a relative concept with respect to aromatics, and is defined to mean a group, compound, or the like that does 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 lower alkoxy 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 specifically, 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 are exemplified. .

  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 each} represents an alkyl group (which may be linear or branched, and preferably has 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 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, the 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 and Y are the same as described 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また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. And the like, in which a hydrogen atom is removed. 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. 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 R ¹⁷ The terminal of each may be bonded.
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- to 7-membered ring, and more preferably a 4- to 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２価の連結基を示す。］

[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 a divalent linking 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).

Examples of the divalent linking group for Y ² include an alkylene group, a divalent aliphatic cyclic group, a divalent linking group containing a hetero atom, or a combination thereof.
As the aliphatic cyclic group, those similar to the description of the “aliphatic cyclic group” can be used except that a group in which two or more hydrogen atoms are removed is used.
When Y ² is an alkylene group, it is preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and 1 to 3 carbon atoms. Most preferably it is.
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. .

When Y ² is a divalent linking group containing a hetero atom, examples of the divalent linking group containing a hetero atom include —O—, —C (═O) —O—, —C (═O) —, -O-C (= O) -O -, - C (= O) -NH -, - NR 04 - (R 04 is an alkyl group, an acyl group, etc.), - NH-C (= O) -, = N _{-, - S -, - S} (= O) 2 -, - S (= O) 2 -O -, "- A-O (oxygen atom) -B- (However, A and B are each independently substituted And a divalent hydrocarbon group which may have a group).

In —NR ⁰⁴ — of Y ² , R ⁰⁴ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
When Y ² is “—A—O—B—”, A and B are each independently a divalent hydrocarbon group which may have a substituent. The hydrocarbon group having “substituent” means that part or all of the hydrogen atoms in the hydrocarbon group are substituted with groups or atoms other than hydrogen atoms.

  The hydrocarbon group in A may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. An aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity.

The aliphatic hydrocarbon group for A may be saturated or unsaturated, and is usually preferably saturated.
Specific examples of the aliphatic hydrocarbon group for A include a linear or branched aliphatic hydrocarbon group, and an aliphatic hydrocarbon group containing a ring in the structure.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 8, still more preferably 2 to 5, and most preferably 2.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable. Specifically, a methylene group, an ethylene group [— (CH ₂ ) ₂ —], a trimethylene group [— (CH ₂ ) ₃ -], tetramethylene group _{[- (CH 2) 4 -} ], a pentamethylene group _{[- (CH 2) 5 -} ] , and the like.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferred, and specifically, —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 - _{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 Alkylethylene groups such as CH ₃ ) CH ₂ —; alkyltrimethylene groups such as —CH (CH ₃ ) CH ₂ CH ₂ —, —CH ₂ CH (CH ₃ ) CH ₂ —; —CH (CH ₃ ) CH _{2 CH 2 CH 2 -, - CH} 2 CH (CH 3) CH 2 CH 2 - , etc. And alkyl alkylene groups such as Le Kill tetramethylene group. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.
The chain-like aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include 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.

Examples of the aliphatic hydrocarbon group including a ring in the structure include a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), and the cyclic aliphatic hydrocarbon group includes the chain described above. And a group that is bonded to the terminal of the chain-like aliphatic hydrocarbon group or intervenes in the middle of the chain-like aliphatic hydrocarbon group.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic group, a group in which two hydrogen atoms have been removed from a monocycloalkane having 3 to 6 carbon atoms is preferable, and examples of the monocycloalkane include cyclopentane and cyclohexane.
As the polycyclic group, a group in which two hydrogen atoms are removed from a polycycloalkane having 7 to 12 carbon atoms is preferable. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, tetra And cyclododecane.
The cyclic aliphatic hydrocarbon group 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.

  A is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 2 to 5 carbon atoms, and most preferably a methylene group or an ethylene group. .

Examples of the hydrocarbon group for B include the same divalent hydrocarbon groups as those described above for A.
B is preferably a linear or branched aliphatic hydrocarbon group, particularly preferably a methylene group or an alkylmethylene group.
The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.

The divalent linking group for Y ² is more preferably an alkylene group, a divalent aliphatic cyclic group, or a divalent linking group containing an alkylene group and a hetero atom, and a divalent linking group containing an alkylene group and a hetero atom. The group is particularly preferred.

  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２価の連結基であり；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 is a divalent linking group; R is the same as defined above; R ¹ ′ and R ² ′ each independently represent a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms. ]

In the formula, X 'include 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 these, the structural unit represented by general formula (a1-1) or (a1-3) is preferable, and specifically, the formula (a1-1-1) to (a1-1-7) and the formula (a1) -1-36) to (a1-1-42), formulas (a1-1-47) to (a1-1-48), formulas (a1-3-49) to (a1-3-56) and formulas ( It is more preferable to use at least one selected from the group consisting of structural units represented by a1-3-57) to (a1-3-58).
Furthermore, as the structural unit (a1), in particular, the structural unit represented by the following general formula (a1-1-01) including the structural units represented by the formulas (a1-1-1) to (a1-1-5). What will be done,
Represented by the following general formula (a1-1-02) including the structural units represented by formulas (a1-1-36) to (a1-1-42);
What is represented by the following general formula (a1-1-03) including the structural units represented by formulas (a1-1-47) to (a1-1-48) and the following general formula (a1-1-04) ),
What is represented by the following general formula (a1-3-01) including the structural units represented by formulas (a1-3-57) to (a1-3-58) and the following general formula (a1-3-02) ),
Represented by the following general formula (a1-3-03) including the structural units of formulas (a1-3-49) to (a1-3-52);
What is represented by the following general formula (a1-3-04) including the structural units of the formulas (a1-3-53) to (a1-3-56) is also preferable.

［式（ａ１−１−０１）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。式（ａ１−１−０２）中、Ｒは前記と同じであり、Ｒ^１２は低級アルキル基を示し、ｈは１〜３の整数を表す。］

[In the formula (a1-1-01), R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and R ¹¹ represents a lower alkyl group. In formula (a1-1-02), R is the same as defined above, 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, preferably a methyl group or an ethyl group, and most preferably a methyl 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.

［式（ａ１−１−０３）中、Ｒは前記と同じであり、Ｒ^１３は炭素数３以上の分岐鎖状のアルキル基である。式（ａ１−１−０４）中、Ｒ、Ｒ^１３は式（ａ１−１−０３）におけるＲ、Ｒ^１３とそれぞれ同じであり、ｔは０〜３の整数である。］

[In formula (a1-1-03), R is the same as defined above, and R ¹³ represents a branched alkyl group having 3 or more carbon atoms. Wherein ^{(a1-1-04), R,} R ¹³ are the same each ^R, and ^{R 13} in formula (a1-1-03), t is an integer of 0 to 3. ]

In general formula (a1-1-03), R is the same as defined above.
R ¹³ is a branched alkyl group having 3 or more carbon atoms, preferably 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specific examples of R ¹³ include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, and the like, and an isopropyl group is most preferable.
In general formula (a1-1-04), R and R ¹³ are the same as R and R ¹³ in general formula (a1-1-03), respectively.
t is an integer of 0 to 3, and 1 or 2 is preferable.

［式（ａ１−３−０１）中、Ｒは前記と同じであり、Ｒ^１４は低級アルキル基であり、ａは１〜１０の整数であり、ｂは１〜１０の整数である。式（ａ１−３−０２）中、Ｒ、Ｒ^１４、ａ、ｂは式（ａ１−３−０１）におけるＲ、Ｒ^１４、ａ、ｂとそれぞれ同じであり、ｔは０〜３の整数である。式（ａ１−３−０３）中、Ｒ、Ｒ^１４、ａ、ｂは式（ａ１−３−０１）におけるＲ、Ｒ^１４、ａ、ｂとそれぞれ同じである。式（ａ１−３−０４）中、Ｒ、Ｒ^１４、ａ、ｂ、ｔは式（ａ１−３−０２）におけるＲ、Ｒ^１４、ａ、ｂ、ｔとそれぞれ同じである。］

[In formula (a1-3-01), R is as defined above, R ¹⁴ is a lower alkyl group, a is an integer of 1 to 10, and b is an integer of 1 to 10. Wherein ^{(a1-3-02), R, R 14} , a, b is ^{R, R 14, a,} b and respectively the same in the formula (a1-3-01), t is an integer of 0 to 3 is there. Wherein ^{(a1-3-03), R, R 14} , a, b is ^{R, R 14, a,} b and respectively the same in the formula (a1-3-01). Wherein ^{(a1-3-04), R, R 14} , a, b, t is ^{R, R 14, a, b} , respectively and t same in formula (a1-3-02). ]

In general formula (a1-3-01) and general formula (a1-3-03), R is the same as described above.
The lower alkyl group for R ^{14 is the same as} the lower alkyl group for R, and is preferably a methyl group or an ethyl group, and more preferably a methyl group.
a is an integer of 1 to 10, an integer of 1 to 5 is preferable, and 1 or 2 is particularly preferable.
b is an integer of 1 to 10, an integer of 1 to 5 is preferable, and 1 or 2 is particularly preferable.

Formula (a1-3-02), in the general formula ^{(a1-3-04), R, R 14} , a, for b, ^R in the general formula ^{(a1-3-01), R 14, a} , b Are the same.
t is an integer of 0 to 3, and 1 or 2 is preferable.

  The total content of the structural unit (a1) in the component (A1) is preferably 10 to 80 mol%, more preferably 20 to 70 mol%, based on the total of all structural units constituting the component (A1). 25-60 mol% 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.

In the component (A1), the proportion of the structural unit represented by the general formula (a1-1-01) or the general formula (a1-1-02) is based on the total of all structural units constituting the component (A1). 10-80 mol% is preferable, 15-70 mol% is more preferable, 15-50 mol% is further 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.
In the component (A1), the proportion of the structural unit represented by the general formula (a1-1-03) or the general formula (a1-1-04) is based on the total of all the structural units constituting the component (A1). 20-70 mol% is preferable, 25-65 mol% is more preferable, and 30-50 mol% is further 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.
In the component (A1), the proportion of the structural unit represented by the general formula (a1-3-01), (a1-3-02), (a1-3-03) or (a1-3-04) is ( 5-50 mol% is preferable with respect to the sum total of all the structural units which comprise A1) component, 5-30 mol% is more preferable, and 10-30 mol% is further 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.

  Each monomer (hereinafter collectively referred to as “monomer W”) for deriving the structural units represented by the general formulas (a1-3-01) to (a1-3-04) is produced by, for example, the following production method. Can be manufactured.

Monomer W Production Method:
In the presence of a base, a compound represented by the following general formula (X-1) (hereinafter referred to as “compound (X-1)”) dissolved in a reaction solvent is represented by the following general formula (X-2). And a compound represented by the following general formula (X-3) (hereinafter referred to as “compound (X-3)”) by adding and reacting the compound (hereinafter referred to as “compound (X-2)”). Then, the compound represented by the following general formula (X-4) is added to the solution in which the compound (X-3) is dissolved in the presence of a base and reacted to obtain the monomer W. .
Compound (X-2) can be obtained, for example, by reacting X ¹¹ —B—C (═O) —OH with X ² —H. Further, instead of the compound (X-2), X ¹¹ —B—C (═O) —OH and X ² —H may be used separately.
Examples of the base include inorganic bases such as sodium hydride, K ₂ CO ₃ and Cs ₂ CO ₃ ; organic bases such as triethylamine, 4-dimethylaminopyridine (DMAP) and pyridine.
Any reaction solvent may be used as long as it can dissolve the starting compounds (X-1) and (X-2). Specifically, tetrahydrofuran (THF), acetone, dimethylformamide (DMF), dimethylacetamide , Dimethyl sulfoxide (DMSO), acetonitrile and the like.

［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；ＡおよびＢはそれぞれ独立して置換基を有していてもよい２価の炭化水素基であり、Ｘ^２は酸解離性溶解抑制基であり、Ｘ^１２およびＸ^１３はそれぞれ独立して水酸基またはハロゲン原子であって、Ｘ^１２およびＸ^１３のいずれか一方が水酸基であり、他方がハロゲン原子であり、Ｘ^１１はハロゲン原子である。ｕは０又は１である。］

[Wherein, R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; A and B are each independently a divalent hydrocarbon group which may have a substituent, and X ² is An acid dissociable, dissolution inhibiting group, X ¹² and X ¹³ are each independently a hydroxyl group or a halogen atom, and one of X ¹² and X ¹³ is a hydroxyl group, the other is a halogen atom, and X ¹¹ Is a halogen atom. u is 0 or 1. ]

In the above formula, R, X ² , A, and B are all the same as described above.
Examples of the halogen atom in X ¹¹ , X ¹² and X ¹³ include a bromine atom, a chlorine atom, an iodine atom and a fluorine atom.
The halogen atom for X ¹² or X ¹³ is preferably a chlorine atom or a bromine atom because of excellent reactivity.
X ¹¹ is preferably a bromine atom or a chlorine atom because of excellent reactivity.
The manufacturing method of the monomer W indicates a manufacturing method of each monomer that derives the structural unit represented by the general formula (a1-3-01) or (a1-3-02) when u = 1, In the case of = 0, the production method of each monomer for deriving the structural unit represented by the general formula (a1-3-03) or (a1-3-04) is shown.

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.
When the component (A1) is used for forming a resist film, the lactone cyclic group of the structural unit (a2) increases the adhesion of the resist film to the substrate or has an affinity for a developer containing water. It is effective in raising.

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 a monocyclic lactone such as γ-butyrolactone or mevalonic lactone. 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 represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ′ represents a hydrogen atom, a lower alkyl group, an alkoxy group having 1 to 5 carbon atoms, or —COOR ″, and R ″ represents 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; A ″ is a carbon which may contain an oxygen atom or a sulfur atom. It is an alkylene group of formulas 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).
The lower alkyl group for R ′ is 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 a group 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 Specifically, a group in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane, or a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane. Etc.
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.

In the component (A1), as the structural unit (a2), one type of structural unit may be used, or two or more types may be used in combination.
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 (a2) -3) At least 1 sort (s) selected from the group which consists of a structural unit represented by 3) is more preferable. 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) at least one selected from the group consisting of structural units It is preferable to use it.

  The proportion of the structural unit (a2) in the component (A1) is preferably from 5 to 60 mol%, more preferably from 10 to 55 mol%, more preferably from 20 to 55, based on the total of all structural units constituting the component (A1). More preferred is mol%. 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 it to 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 (A) 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 part of hydrogen atoms of the alkyl group is substituted with a fluorine atom, and 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, the structural unit represented by the following formula (a3-1), the structural unit represented by the following formula (a3-2), and the following formula The structural unit represented by (a3-3) and the structural unit represented by the following formula (a3-4) are preferred.

［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の整数であり、ｄ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] S is an integer of 1 to 3, and d 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. In these, a 2-norbornyl group or a 3-norbornyl group is preferably 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.

  In formula (a3-4), d is preferably 1 or 2, and more preferably 1. The bonding position of the hydroxyl group is not particularly limited. When d is 1, the 2nd position is preferable because it is readily available and inexpensive. When d is 2 or 3, arbitrary substitution positions can be combined.

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

-About structural unit (a4) (A1) component may contain other structural units (a4) other than the said structural units (a1)-(a3) in the range which does not impair the effect of this invention.
The structural unit (a4) is not particularly limited as long as it is another structural unit that is not classified into the structural units (a1) to (a3) described above, and is for ArF excimer laser and 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。］

[Wherein, R is the same as defined above. ]

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

  In the present invention, the component (A1) is preferably a polymer compound having the structural unit (a1). Examples of the polymer compound include a copolymer comprising the structural unit (a1) and the structural unit (a2), Copolymer comprising unit (a1) and structural unit (a3); copolymer comprising structural unit (a1), structural unit (a2) and structural unit (a3); structural unit (a1), structural unit (a2) And a copolymer composed of the structural unit (a3) and the structural unit (a4).

In the component (A), as the component (A1), one type may be used alone, or two or more types may be used in combination.
In the present invention, as the component (A1), a polymer compound containing the following combination of structural units is particularly preferable.

［式（Ａ１−１１）中、Ｒは前記と同じであり、複数のＲはそれぞれ同じであっても異なっていてもよい。Ｒ^２０は低級アルキル基である。］

[In formula (A1-11), R is the same as defined above, and the plurality of R may be the same or different. R ²⁰ is a lower alkyl group. ]

In formula (A1-11), the lower alkyl group for R ^{20 is the same as} the lower alkyl group for R, preferably a methyl group or an ethyl group, and most preferably a methyl group.

［式（Ａ１−２１）中、Ｒは前記と同じであり、複数のＲはそれぞれ同じであってもよく異なっていてもよい。Ｒ^１３、Ｒ^１４、ａおよびｂは、いずれも前記と同じである。］

[In formula (A1-21), R is the same as defined above, and the plurality of R may be the same or different. R ¹³ , R ¹⁴ , a and b are all the same as described above. ]

In the formula (A1-21), the branched alkyl group having 3 or more carbon atoms of R ¹³ is most preferably an isopropyl group.
The lower alkyl group for R ¹⁴ is preferably a methyl group or an ethyl group, and most preferably a methyl group.
a is an integer of 1 to 10, 1 or 2 is particularly preferable, and 1 is most preferable.
b is an integer of 1 to 10, 1 or 2 is particularly preferable, and 1 is most preferable.

The component (A1) is obtained by polymerizing a monomer that derives each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate. be able to.
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) of the component (A1) (polystyrene conversion standard by gel permeation chromatography) is not particularly limited, preferably 2000 to 50000, more preferably 3000 to 30000, most preferably 5000 to 20000. preferable. If it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and if it is above 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.

(A) A component may be used individually by 1 type and may use 2 or more types together.
Among the above, the component (A) preferably contains the component (A1).
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>
In this invention, (B) component contains the acid generator (B1) (henceforth "(B1) component") consisting of a compound represented by the following general formula (b1-1).

［式中、Ｙ^１１は置換基を有していてもよい炭素数１〜４のフッ素化アルキル基であり、Ｙ^１２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、Ｙ^１３は単結合又は二価の連結基であり、Ｘ^１０は置換基を有していてもよい炭素数３〜３０の環状の炭化水素基であり；Ａ^＋は有機カチオンである。］

[Wherein Y ¹¹ is an optionally substituted fluorinated alkyl group having 1 to 4 carbon atoms, and Y ¹² is an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. Y ¹³ is a single bond or a divalent linking group, X ¹⁰ is an optionally substituted cyclic hydrocarbon group having 3 to 30 carbon atoms; A ⁺ is an organic cation is there. ]

· (B1) in the the anion moiety of the component formula ^{(b1-1), Y 11} is a fluorinated alkyl group of 1 to 4 carbon atoms which may have a substituent. When Y ¹¹ is a fluorinated alkyl group, the strength of the acid generated by exposure is increased and the lithography properties are improved.
The fluorinated alkyl group for Y ¹¹ may be linear, branched or cyclic, and is preferably linear or branched.
The fluorinated alkyl group has 1 to 4 carbon atoms, and examples of the alkyl group (before being substituted with a fluorine atom) in the fluorinated alkyl group include a methyl group, an ethyl group, a propyl group, and an isopropyl group. , N-butyl group, tert-butyl group and the like.
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 particularly preferable, and a perfluoroalkyl group is most preferable.

In Y ¹¹ , the fluorinated alkyl group may have a substituent.
The term “having a substituent” for a fluorinated alkyl group means that part or all of the hydrogen atom or fluorine atom in the fluorinated alkyl group is substituted with an atom or group other than a hydrogen atom and a fluorine atom. To do.
Examples of the substituent that the fluorinated alkyl group may have include an alkoxy group, a halogen atom (excluding a fluorine atom), a hydroxyl group, and an oxygen atom (═O).
The alkoxy group of the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group. A group and an ethoxy group are particularly preferred.
Examples of the halogen atom for the substituent include a chlorine atom, a bromine atom, and an iodine atom.

In the formula ^{(b1-1), Y 12} is a fluorinated alkylene group of 1 to 4 carbon atoms which may have a substituent.
Carbon number of this fluorinated alkylene group is 1-4, and 1-2 are especially preferable.
Since the component (B1) has a skeleton of “Y ¹¹ —SO ₂ —”, for example, a perfluoroalkyl chain having 6 to 10 carbon atoms is hardly decomposable, whereas the skeleton has good decomposability. Moreover, the effect that the handleability in consideration of the bioaccumulation property is further improved can be obtained. Further, it is preferable because it is uniformly distributed in the resist film.

As fluorinated alkylene group of Y ^12, _{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 _{CH 2 CF 2 -, - CH} 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.

Among the above, Y ¹² is more preferable as the number of hydrogen atoms in the alkylene group substituted with a fluorine atom is larger because the strength of the acid is increased and the lithography properties are further improved.
The fluorination rate of the fluorinated alkyl group is preferably 70 to 100%, more preferably 90 to 100%, and most preferably a perfluoroalkylene group in which all hydrogen atoms are substituted with fluorine atoms.
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, and —CF ₂ CF ₂ — is most preferable because the effects of the present invention can be obtained particularly well.

In Y ¹² , the fluorinated alkylene group may have a substituent.
The term “having a substituent” for the fluorinated alkylene group means that part or all of the hydrogen atom or fluorine atom in the fluorinated alkylene group is substituted with an atom or group other than a hydrogen atom and a fluorine atom. To do.
Examples of the substituent that the fluorinated alkylene group may have include an alkoxy group having 1 to 4 carbon atoms and a hydroxyl group.

In formula (b1-1), Y ¹³ represents a single bond or a divalent linking group.
In Y ¹³ , examples of the divalent linking group 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) —, —C (═O) —O—R ⁹³ —O—C (═O) — , R ^{91 to} R ⁹³ are each independently an alkylene group.) And the like.
The alkylene group for R ^{91 to} R ⁹³ 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. preferable.
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.

Y ¹³ is preferably a single bond, an ester bond, a divalent linking group containing an ester bond, an ether bond, or a divalent linking group containing an ether bond. Among them, an ester bond, an ether bond, -R ^91- O—, —R ⁹² —O—C (═O) —, or —C (═O) —O—R ⁹³ —O—C (═O) — are more preferred, and an ether bond is particularly preferred.

In the formula ^{(b1-1), X 10} is a cyclic hydrocarbon group of 3 to 30 carbon atoms which may have a substituent.
The cyclic hydrocarbon group for X ¹⁰ may be an aromatic hydrocarbon group or a cyclic aliphatic hydrocarbon group. Further, such a cyclic hydrocarbon group may be a group consisting only of a ring, or a group consisting of a ring and a chain group.

In X ^10, 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 number of carbon atoms in 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 cyclic aliphatic hydrocarbon group for X ¹⁰ may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group.
In X ¹⁰ , the cyclic aliphatic hydrocarbon group has a carbon atom constituting the cyclic aliphatic hydrocarbon group partially substituted with a substituent containing a hetero atom (excluding a nitrogen atom). Alternatively, part or all of the hydrogen atoms constituting the aliphatic hydrocarbon group may be substituted with a substituent containing a hetero atom (excluding a nitrogen atom).
The “heteroatom” in X ¹⁰ is not particularly limited as long as it is an atom other than a carbon atom, a hydrogen atom and a nitrogen atom, and examples thereof include a halogen atom, an oxygen atom and a sulfur 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 (excluding a nitrogen atom) may be composed of only the hetero atom, or may be a group containing a group other than the hetero atom or an 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. _{-, - S -, - S} (= O) 2 -, - S (= O) 2 -O- , and the like. 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, and an oxygen atom (═O).
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.

In X ^10, the aliphatic hydrocarbon group constituting the ring (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 one or more hydrogen atoms from the polycycloalkane are substituted. Excluded groups are preferred, and most preferred are groups in which one or more hydrogen atoms have been removed from adamantane.
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.]

The alkylene group for Q ″ may be linear or branched. The alkylene group preferably has 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.
As the alkylene group for R ⁹⁴ and R ^95, the same alkylene groups as those described above for Q ″ 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.

Further, in X ^10, the cyclic aliphatic hydrocarbon group also include groups having an alkylene group bonded thereto and a monovalent aliphatic cyclic group.
Such a monovalent aliphatic cyclic group include the same as the aliphatic hydrocarbon group constituting the ring in the description of the X ¹⁰ (aliphatic cyclic group).
Examples of the alkylene group include the same alkylene groups as those described above for Q ″.

In the present invention, X ¹⁰ is preferably an aliphatic cyclic group which may have a substituent, or a group having a monovalent aliphatic cyclic group and an alkylene group bonded thereto.
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), etc. An adamantyl group is most preferred.

As X ^10, more specifically, (B1) from the lithography properties are improved when an acid generator including the components used in the resist composition, the following chemical formula ^{(X 10 -1) ~ (X} 10 - An aliphatic hydrocarbon group represented by 5) is preferred, and an adamantyl group represented by the chemical formula (X ¹⁰ -2) is most preferred.

-About the cation part of (B1) component In said Formula (b1-1), A ^<+> is an organic cation.
The organic cation of A ⁺ is not particularly limited, and any conventionally known cation part of an onium salt acid generator can be used as appropriate.
As such a cation moiety, a sulfonium ion or an iodonium ion is preferable, and a sulfonium ion is particularly preferable.
Specific examples include cations 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 ″ each independently represents an aryl group which may have a substituent, or an alkyl group which may have a substituent, and R ¹ ″ to R ³ "At least one of" 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 ″ each independently represents an aryl group which may have a substituent, or an alkyl group which may have a substituent, and R ⁵ ″ to R ⁶ ″. At least one of them 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, at least one of R ¹ ″ to R ³ ″ represents an aryl group. Of R ¹ ″ to R ³ ″, two or more are preferably aryl groups, and it is most preferable that all of R ¹ ″ to R ³ ″ are 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, a part or all of hydrogen atoms of the unsubstituted aryl group being an alkyl group, alkoxy group, an 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, particularly 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 particularly 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.

As the alkoxyalkyloxy group in the substituted aryl group, for example,
General formula: -O-C ( ^R47 ) ( ^R48 ) -O- ^R49
[Wherein, R ⁴⁷ and R ⁴⁸ each independently represent a hydrogen atom or a linear or branched alkyl group, and R ⁴⁹ represents an alkyl group. ] Is represented.
In R ⁴⁷ and R ⁴⁸ , the alkyl group preferably has 1 to 5 carbon atoms, and may be linear or branched, 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 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. Groups obtained by removing one or more hydrogen atoms from polycycloalkanes and the like. 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 for R 1 ^{"~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 to form a 5- to 7-membered ring.
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) tetrahydrothioff 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. It is preferable that all of R ⁵ ″ to R ⁶ ″ are aryl groups.
As the aryl group for R ⁵ ″ to R ⁶ ″, the same as the aryl groups for R ¹ ″ to R ³ ″ can be used.
Examples of the alkyl group for R ⁵ ″ to R ⁶ ″ include the same as the alkyl group for R ¹ ″ to R ³ ″.
Among these, it is most preferable that R ⁵ ″ to R ⁶ ″ are all phenyl groups.
Specific examples of the cation moiety represented by the formula (I-2) include diphenyliodonium, bis (4-tert-butylphenyl) iodonium, and the like.

Moreover, as for A ^<+> , the cation represented by the following general formula (I-5) or (I-6) is mentioned as a preferable cation part.

［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 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 code 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 the following formulas (I-1-9) to (I-1-10), R ⁹ and R ¹⁰ 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.
v is an integer of 1 to 3, and 1 or 2 is most preferable.

  In the present invention, as the component (B1), compounds (B1-1) to (B1-5) represented by the following general formulas (b1-1-1) to (b1-1-5) are preferable.

［式中、Ａ^＋は有機カチオンであり、ｇは１〜４の整数であり、ｔ１〜ｔ５は１〜４の整数であり、ｍ_１〜ｍ_５は０又は１であり、ｗ１〜ｗ４はそれぞれ独立に０〜３の整数であり、Ｒ^２１〜Ｒ^２４は置換基である。］

[A wherein, ^{A +} is an organic cation, g is an integer from 1 to 4, t1 to t5 is an integer of 1 to _4, m 1 ~m ₅ is 0 or 1, the w1~w4 Each independently represents an integer of 0 to 3, and R ^{21 to} R ²⁴ are substituents. ]

In the above formula, as described above, A ⁺ is preferably a cation moiety represented by the general formula (I-1) or (I-5), and represented by the general formula (I-1). Particularly preferred is a cation moiety.
g is an integer of 1-4 independently, 1 or 2 is preferable and 1 is the most preferable.
t1 to t5 are each independently an integer of 1 to 4, preferably 1 or 2, and most preferably 2.
m _{1 to} m ₅ are each independently 0 or 1, and 0 is preferable.
w1 to w4 are each independently an integer of 0 to 3, preferably 0 or 1, and most preferably 0.
Examples of the substituent for R ^{21 to} R ²⁴ include the same groups as those described above as the substituent that the aliphatic hydrocarbon group may have in X ¹⁰ .
If signs placed R ²¹ ~R ²⁴ (w1~w4) is an integer of 2 or more, plural ^R 21 ^{to R 24} in the compound may be the same, respectively, it may be different.

  Among these, as the component (B1), a compound (B1-10) represented by the following general formula (b1-10) is particularly preferable.

［式中、Ｒ^１”〜Ｒ^３”は前記と同じであり、ｇは前記と同じであり；ｔ７は１〜４の整数であり、ｍ_７は０又は１であり、ｖ_１は０〜３の整数であり、ｗ５は０〜３の整数であり、Ｒ^２５は置換基である。］

[Wherein, R ¹ ″ to R ³ ″ are the same as described above, g is the same as described above; t7 is an integer of 1 to 4, m ₇ is 0 or 1, and v ₁ is 0 to 0] 3 is an integer of 3, w5 is an integer of 0 to 3, and R ²⁵ is a substituent. ]

In said formula (b1-10), t7 is an integer of 1-4, 1 or 2 is preferable and 2 is the most preferable.
m ₇ is 0 or 1, and 0 is preferable.
v ₁ represents an integer of 0 to 3, preferably 0 or 1.
w5 is an integer of 0 to 3, preferably 0 or 1, and most preferably 0.
R ²⁵ is a substituent, and examples thereof include the same substituents as R ^{21 to} R ²⁴ described above.

As the component (B1), 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 (B1) in the component (B) is preferably 40% by mass or more, more preferably 70% by mass or more, and may be 100% by mass. Most preferably, it is 100 mass%. When the ratio of the component (B1) is not less than the lower limit of the above range, when a resist pattern is formed using the resist composition of the present invention, resolution, line width roughness (LWR), mask reproducibility, etc. Lithographic properties are improved.

[(B2) component]
In the resist composition of the present invention, the component (B) may contain an acid generator other than the component (B1) (hereinafter referred to as “component (B2)”) as necessary.
The component (B2) is not particularly limited as long as it does not correspond to the component (B1), and any of those that have been proposed as acid generators for chemically amplified resists can be used. Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, poly (bissulfonyl) diazomethanes, and the like. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  As the onium salt acid generator, for example, a compound represented by the following general formula (b-1) or (b-2) can be used.

［式（ｂ−１）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（ｂ−２）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。複数のＲ^４”は、それぞれ独立して、置換基を有していてもよいアルキル基、ハロゲン化アルキル基、アリール基、またはアルケニル基を表す。］

[In formula (b-1), R ¹ ″ to R ³ ″ each independently represents an aryl group which may have a substituent, or an alkyl group which may have a substituent; ^At least one of ¹ ″ to R ³ ″ 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 formula (b-2), R ⁵ ″ and R ⁶ ″ each independently represents an aryl group which may have a substituent, or an alkyl group which may have a substituent, and R ⁵ At least one of “˜R ⁶ ” is the aryl group. A plurality of R ⁴ ″ each independently represents an optionally substituted alkyl group, halogenated alkyl group, aryl group, or alkenyl 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 ″ to R ⁶ ″ are the same as R ⁵ ″ to R ⁶ ″ in formula (I-2), respectively.

In formula (b-1) or (b-2), R ⁴ ″ represents an alkyl group, a halogenated alkyl group, an aryl group, or an alkenyl group which may have a substituent.
The alkyl group for R ⁴ ″ may be linear, branched or cyclic.
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.

Examples of the halogenated alkyl group for R ⁴ ″ include groups in which part or all of the hydrogen atoms of the linear, branched, or cyclic alkyl group have been substituted with halogen atoms. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, A fluorine atom is preferable.
In the halogenated alkyl group, the ratio of the number of halogen atoms to the total number of halogen atoms and hydrogen atoms contained in the halogenated alkyl group (halogenation rate (%)) is preferably 10 to 100%. 50 to 100% is preferable, and 100% is most preferable. The higher the halogenation rate, the better the acid strength.

The aryl group for R ⁴ ″ is preferably an aryl group having 6 to 20 carbon atoms.
The alkenyl group in R ⁴ ″ is preferably an alkenyl group having 2 to 10 carbon atoms.

In the above R ⁴ ″, “optionally substituted” means one of hydrogen atoms in the linear, branched or cyclic alkyl group, halogenated alkyl group, aryl group, or alkenyl group. It means that part or all may be substituted with a substituent (an atom or group other than a hydrogen atom).
The number of substituents in R ⁴ ″ may be one or two or more.

Examples of the substituent include a halogen atom, a hetero atom, and an alkyl group.
Examples of the halogen atom and alkyl group include the same groups as those described as the halogen atom and alkyl group in the halogenated alkyl group in R ⁴ ″.
Examples of the hetero atom include an oxygen atom, a nitrogen atom, and a sulfur atom.

  Specific examples of the onium salt acid generators represented by formulas (b-1) and (b-2) include diphenyliodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, bis (4-tert-butylphenyl) iodonium. Trifluoromethane sulfonate or nonafluorobutane sulfonate, triphenylsulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, tri (4-methylphenyl) sulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its Nonafluorobutanesulfonate, dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethanesulfonate, its heptaful Lopropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of monophenyldimethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; trifluoromethanesulfonate of diphenylmonomethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate (4-methylphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate , Trifluoromethanesulfonate of tri (4-tert-butyl) phenylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenyl (1- (4-methoxy) naphthyl) sulfonium, its heptafluoropropane Sulfonate or its nonafluorobutane sulfonate, di (1-naphthyl) phenyl sulphonium trifluoromethane sulphonate, its heptafluoropropane sulphonate or its nonafluorobutane sulphonate; 1-phenyltetrahydrothiophenium trifluoromethane sulphonate, its heptafluoropropane sulphonate Or nonafluorobutanesulfonate thereof; 1- (4-methylphenyl) ) Tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate 1- (4-methoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1- (4-ethoxynaphthalene-1- Yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonaflu 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1-phenyltetrahydrothiopyranium trifluoromethanesulfonate , Its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (4-hydroxyphenyl) tetrahydrothiopyranium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl -4-Hydroxyphenyl) tetrahydrothiopyranium trifluoromethanesulfonate, its heptafluoropropanes Honeto or nonafluorobutanesulfonate; 1- (4-methylphenyl) trifluoromethanesulfonate tetrahydrothiophenium Pila chloride, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, and the like.

  Moreover, the onium salt which replaced the anion part of these onium salts with alkyl sulfonates, such as methanesulfonate, n-propanesulfonate, n-butanesulfonate, n-octanesulfonate, can also be used.

  Moreover, as an onium salt type acid generator, the anion part in the said general formula (b-1) or (b-2) is changed into the anion represented by the following general formula (b-3) or (b-4). A substituted onium salt acid generator 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, preferably 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 ″, as the number of hydrogen atoms substituted with fluorine atoms increases, the strength of the acid increases, and high-energy light and electrons of 200 nm or less This is preferable because the transparency to the line is improved.
The proportion of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are substituted with fluorine atoms. A perfluoroalkylene group or a perfluoroalkyl group.

The cation moiety is a cation represented by the general formula (I-5) or (I-6), and the anion moiety is the anion moiety in the general formula (b-1) or the formula (b-2). It is also possible to use a fluorinated alkyl sulfonate ion such as (R ⁴ ″ SO ₃ ⁻ ) or an onium salt acid generator substituted with an anion represented by the general formula (b-3) or the formula (b-4). it can.
Among these, the anion moiety is preferably a fluorinated alkyl sulfonate ion, more preferably a fluorinated alkyl sulfonate ion having 1 to 4 carbon atoms, and a linear perfluoroalkyl sulfonic acid having 1 to 4 carbon atoms. Ions are particularly preferred. Specific examples include trifluoromethyl sulfonate ion, heptafluoro-n-propyl sulfonate ion, nonafluoro-n-butyl sulfonate ion, and the like.

  In this specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid upon irradiation (exposure) of radiation. It is what you have. 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 “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 having no substituent or a fluorinated alkyl group having 1 to 4 carbon atoms.

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 formula 18] to [chemical formula 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 (B2), one type of acid generator may be used alone, or two or more types may be used in combination.

0.5-50 mass parts is preferable with respect to 100 mass parts of (A) component, and, as for the total content of the (B) component in the resist composition of this invention, 1-30 mass parts is more preferable, 2-20 Part by mass is most preferred.
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>
[(D) component]
Since the resist composition of the present invention improves the resist pattern shape, the stability over time, and the like, a nitrogen-containing organic compound component (D) (hereinafter referred to as “component (D)”) is further added as an optional component. It is preferable to contain.
Since a wide variety of components (D) have already been proposed, any known one may be used. Among them, aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are used. preferable. Here, the aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 20 carbon atoms.
Examples of the aliphatic amine include an amine (alkylamine 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 20 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-hexylamine, tri-n-pentylamine , Tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, tri-n-dodecylamine, etc .; diethanolamine, triethanolamine, diisopropanolamine Triisopropanolamine, di -n- octanol amine, tri -n- octanol amine, lauryl diethanolamine, alkyl alcohol amines such as stearyl diethanolamine. Among these, C5-C10 trialkylamine and alkyl alcohol amine are preferable, and tri-n-pentylamine is particularly preferable.
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.
Examples of the aromatic amine include aniline, pyridine, 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, diphenylamine, triphenylamine, and tribenzylamine.
Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, tris {2 -(1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris [2- {2- (2-hydroxy Ethoxy) ethoxy} ethylamine and the like.
These may be used alone or in combination of two or more.
(D) component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

[(E) 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 include phosphoric acid, phosphonic acid, and phosphinic acid. 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 the 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.
(E) A 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 further contains miscible additives as desired, for example, an additional resin for improving the performance of the resist film, a surfactant, a dissolution inhibitor, and a plasticizer for improving coatability. Stabilizers, colorants, antihalation agents, dyes, and the like can be added as appropriate.

[(S) component]
The resist composition of the present invention can be produced by dissolving the material in an organic solvent (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; Monohydric alcohols; compounds having an ester bond, such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl of the polyhydric alcohols or compound having the 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.
The amount of component (S) used is not particularly limited and is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. In general, the solid content concentration of the resist composition is 2 -20% by mass, preferably 5-15% by mass.

The resist composition of the present invention described above is a novel one that has not been known so far.
According to the resist composition of the present invention, in forming a fine resist pattern, line width roughness (LWR) is reduced, mask reproducibility (for example, mask linearity, mask error factor, etc.) is improved, and the hole pattern is formed. It is possible to form a resist pattern with good lithography characteristics such as improvement in the roundness of holes. The reason why such an effect is obtained is not clear, but is presumed as follows.
That is, in the compound represented by the general formula (b1-1), “—N ^—— SO ₂ —Y ¹² —Y ¹³ —X ¹⁰ ” is bonded to a skeleton having an anion portion of “Y ¹¹ —SO ₂ —”. Has the structure. For this reason, it has a three-dimensionally bulky and bulky structure as compared with the fluorinated alkyl sulfonate ions conventionally used as the anion portion of the acid generator. In addition, since the compound has high lipophilicity, dispersibility in the resist is improved, and further, due to its bulky three-dimensional structure, compared with the anion portion of conventional acid generators such as nonafluorobutanesulfonate, It is presumed that the diffusion of the anion part (acid) in the above is suppressed both chemically and physically.
In addition, in this compound, since Y ¹¹ and Y ¹² adjacent to SO ₂ are both fluorinated, the strength of the acid generated by exposure increases. Thereby, the solubility with respect to the alkali developing solution of a base material component (A) changes more.
As described above, in the resist composition of the present invention, the diffusion of the acid generated in the exposed area to the unexposed area is suppressed, and the solubility of the base component (A) in the alkaline developer is further changed. A sufficient difference in solubility (dissolution contrast) in the alkali developer between the unexposed area and the exposed area can be sufficiently obtained.
Therefore, it is estimated that such an effect can be obtained by the resist composition of the present invention.

  Moreover, since the acid generator of the present invention comprising the compound represented by the general formula (b1-1) does not generate a PFAS compound as an acid generated by exposure, a resist containing such an acid generator is used. The composition is excellent in handleability in consideration of bioaccumulation.

≪Resist pattern formation method≫
The resist pattern forming method according to the second aspect of the present invention includes a step of forming a resist film on a support using the resist composition according to the first aspect of the present invention, a step of exposing the resist film, And a step of alkali developing the resist film to form a resist pattern.
The resist pattern forming method of the present invention can be performed, for example, as follows.
That is, first, the resist composition is coated on 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, at a temperature 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 alkali-development-processed using alkaline developing solution, for example, 0.1-10 mass% tetramethylammonium hydroxide (TMAH) aqueous solution, Preferably, water rinse is carried out using a pure water, and it dries. In some cases, a baking treatment (post-baking) may be performed after the alkali development treatment. 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 of the present invention is effective for KrF excimer laser, ArF excimer laser, EB or EUV, and particularly effective for 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, at the time of exposure, a solvent (having a refractive index larger than the refractive index of air) is formed between a lens and a resist film on the wafer, which is conventionally filled with an inert gas such as air or nitrogen. Exposure is performed in a state filled with the 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 that state, exposure can be performed through a desired mask pattern (immersion exposure).
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 fluorine-based inert liquid include a fluorine-based compound 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 a main component. 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.).

≪Compound≫
The compound according to the third aspect of the present invention is a compound represented by the following general formula (b1-1), and is contained in the component (B) of the resist composition according to the first aspect of the present invention described above. This is the same as the component (B1).

［式中、Ｙ^１１は置換基を有していてもよい炭素数１〜４のフッ素化アルキル基であり、Ｙ^１２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、Ｙ^１３は単結合又は二価の連結基であり、Ｘ^１０は置換基を有していてもよい炭素数３〜３０の環状の炭化水素基であり；Ａ^＋は有機カチオンである。］

[Wherein Y ¹¹ is an optionally substituted fluorinated alkyl group having 1 to 4 carbon atoms, and Y ¹² is an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. Y ¹³ is a single bond or a divalent linking group, X ¹⁰ is an optionally substituted cyclic hydrocarbon group having 3 to 30 carbon atoms; A ⁺ is an organic cation is there. ]

  The description about the compound of this invention is the same as the description about the said (B1) component.

(Method for producing compound)
The compound which is the third aspect of the present invention includes, for example, a compound (III ′) represented by the following general formula (III-0) and a compound (IV ′) represented by the following general formula (IV-0): It can manufacture by making these react.

In the formula ^{(III-0), Y 11} , Y 12, Y 13 and ^{X 10} are respectively the same as ^{Y 11, Y 12, Y 13} and ^{X 10} in the general formula (b1-1).
M ⁺ is an alkali metal ion. Examples of M ⁺ include sodium ion, lithium ion, potassium ion and the like, and sodium ion or lithium ion is preferable.

In the formula (IV-0), A ⁺ is the same as described above.
Z ⁻ is a low nucleophilic halogen ion, an ion that can be an acid having a lower acidity than the compound (III ′), BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ or ClO ₄ ⁻ . .
Examples of the low nucleophilic halogen ion in Z ⁻ include bromine ion and chlorine ion.
Examples of ions that can be an acid having a lower acidity than the compound (III ′) in Z ⁻ include p-toluenesulfonic acid ions, methanesulfonic acid ions, benzenesulfonic acid ions, and trifluoromethanesulfonic acid ions.

Compound (III ′) and compound (IV ′) can be reacted, for example, by dissolving these compounds in a solvent such as water, dichloromethane, acetonitrile, methanol, chloroform, methylene chloride and stirring.
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 (III ′) and compound (IV ′), the reaction temperature, etc., but usually 0.5 to 30 hours are preferable, and 1 to 20 hours are more preferable.
The amount of compound (IV ′) used in the above reaction is usually preferably about 0.5 to 2 mol per 1 mol of compound (III ′).

The structure of the compound of the present invention obtained as described above includes ¹ H-nuclear magnetic resonance (NMR) spectrum method, ¹³ C-NMR spectrum method, ¹⁹ F-NMR spectrum method, infrared absorption (IR) spectrum method, mass It can be confirmed by a general organic analysis method such as analysis (MS) method, elemental analysis method or X-ray crystal diffraction method.

  The method for producing the compound (III ′) is not particularly limited. For example, the compound (II ′) represented by the following general formula (II-0) and the following general formula (I-0) are used. A method comprising a step of obtaining a compound (III ′) by reacting the compound (I ′) obtained in the presence of a base with an organic solvent is preferably used.

In the general formula (II-0) and ^{(I-0), Y 11} , Y 12, Y 13 and ^{X 10} are each, ^Y 11 in the formula ^{(III-0), Y 12} , Y 13 and X ¹⁰ is the same.
X _h is a halogen atom, and examples thereof include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
As compound (II ′) and compound (I ′), commercially available compounds may be used or synthesized.

In the reaction between the compound (II ′) and the compound (I ′), the compound (I ′) is first dissolved in a suitable organic solvent, and it is stirred in the presence of a suitable base. Thereafter, the reaction solution is ice-cooled, and the compound (II ′) is added and stirred. Also, the reaction mixture is filtered and the filtrate is dried.
Finally, it can be carried out by washing with an organic solvent or the like.
In the above reaction, it is particularly preferable to use acetone, tetrahydrofuran (THF), methanol, ethanol, or dichloromethane as the organic solvent because the yield and purity of the resulting compound (III ′) are improved.
The reaction temperature is preferably about 20 ° C to 200 ° C, more preferably about 20 ° C to 150 ° C.
The reaction time varies depending on the reactivity of the compound (II ′) and compound (I ′), the reaction temperature, and the like, but usually 1 to 80 hours is preferable, and 3 to 70 hours is more preferable.

  The amount of the compound used in the reaction is not particularly limited, and usually, compound (I ′) is preferably about 0.5 to 5 mol, preferably about 1 to 5 mol relative to 1 mol of compound (II ′). Is more preferable.

Examples of the base include sodium carbonate, potassium carbonate, triethylamine, sodium hydride and the like, and these may be used alone or in combination of two or more.
The amount of the base used may be a catalytic amount or an amount corresponding to the solvent, and is usually about 0.001 to 5 mol with respect to 1 mol of compound (II ′).

The structure of the compound (III ′) obtained as described above is as follows: ¹ H-nuclear magnetic resonance (NMR) spectrum method, ¹³ C-NMR spectrum method, ¹⁹ F-NMR spectrum method, infrared absorption (IR) spectrum method, It can be confirmed by general organic analysis methods such as mass spectrometry (MS), elemental analysis, and X-ray crystal diffraction.

  The compound of the present invention described above is a novel compound useful as an acid generator for a resist composition, and can be blended in a resist composition as an acid generator.

≪Acid generator≫
The acid generator which is the 4th aspect of this invention consists of a compound represented by the said general formula (b1-1).
The acid generator is useful as an acid generator for a chemically amplified resist composition, for example, the acid generator component (B) of the resist composition according to the first aspect of the present invention.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.

Example 1
Compound (V) was synthesized according to Synthesis Examples 1-2 shown below.

[Synthesis Example 1] (Synthesis of Compound (III))
1.71 g of compound (I) and 17.1 g of THF were stirred with ice cooling, and 0.45 g of sodium hydride was added. Thereto, a liquid mixture of 3.62 g of compound (II) and 7.24 g of THF was added while maintaining the temperature at 10 ° C. or lower, and then reacted for 20 hours under reflux. Thereafter, 22 mL of water and 44 g of t-butyl methyl ether (TBME) were added in this order and stirred, and the TBME layer was collected. This was purified to dryness to obtain 1.2 g (purity%, yield 24%) of a transparent liquid as compound (III).

The obtained compound (III) was analyzed by NMR.
¹ H-NMR (acetone, 400 MHz): δ (ppm) = 1.60 (m, 6H, adamantane), 2.08 (m, 6H, adamantane), 2.17 (m, 3H, adamantane)
¹⁹ F-NMR (acetone, 376 MHz): δ (ppm) = − 68.4 (s, 2F, c), −75.3 (s, 3F, a), −112.0 (s, 2F, b)
From the results of the above analysis, it was confirmed that the obtained compound (III) had a structure represented by the chemical formula (III).

[Synthesis Example 2] (Synthesis of Compound (V))
1.2 g of compound (IV) and 1.70 g of compound (III) were dissolved in 12 g of water. Thereto, 16 g of methylene chloride was added and stirred at room temperature for 3 hours. Thereafter, the organic layer was recovered and washed twice with 1% hydrochloric acid and four times with pure water. The organic layer was collected and concentrated to dryness to obtain 2.2 g (yield 88%) of a transparent highly viscous liquid as compound (V).

The obtained compound (V) was analyzed by NMR.
¹ H-NMR (DMSO, 400 MHz): δ (ppm) = 7.71-7.86 (m, 12H, phenyl), 7.57-7.59 (d, 2H, phenyl), 2.43 (s , 3H, methyl), 2.13 (m, 3H, adamantane), 1.99 (m, 6H, adamantane), 1.59 (s, 6H, adamantane)
¹⁹ F-NMR (DMSO, 376 MHz): δ (ppm) = − 69.2 (s, 2F, c), −76.0 (s, 3F, a), −112.9 (s, 2F, b)
From the results of the above analysis, it was confirmed that the obtained compound (V) had a structure represented by the chemical formula (V).

(Production Example 1)
The polymer compound (1) was synthesized according to Synthesis Examples 3 to 5 shown below.

[Synthesis Example 3] (Synthesis of 2- (2- (2-methyl-2-adamantyloxy) -2-oxoethoxy) -2-oxoethanol)
A 2 L three-necked flask equipped with a thermometer, a condenser and a stirrer was charged with 37.6 g (494 mmol) of glycolic acid, 700 mL of DMF, 86.5 g (626 mmol) of potassium carbonate, and 28.3 g (170 mmol) of potassium iodide at room temperature. For 30 minutes. Then, 300 mL of dimethylformamide in 100 g (412 mmol) of 2-methyl-2-adamantyl chloroacetate was slowly added. The temperature was raised to 40 ° C. and stirred for 4 hours. After completion of the reaction, 2000 mL of diethyl ether was added and filtered, and the resulting solution was washed 3 times with 500 mL of distilled water. Crystallization was performed using a mixed solution of toluene (300 mL) and heptane (200 mL) to obtain 78 g (yield 67%, GC purity 99%) of the target compound as a colorless solid.

The instrumental analysis results of the obtained compound were as follows.
¹ H-NMR: 1.59 (d, 2H, J = 12.5 Hz), 1.64 (s, 3H), 1.71 to 1.99 (m, 10H), 2.29 (m, 2H) 2.63 (t, 1H, J = 5.2 Hz), 4.29 (d, 2H, J = 5.2 Hz), 4.67 (s, 2H).
¹³ C-NMR: 22.35, 26.56, 27.26, 32.97, 34.54, 36.29, 38.05, 60.54, 61.50, 89.87, 165.97, 172 .81.
GC-MS: 282 (M +, 0.02%), 165 (0.09%), 149 (40%), 148 (100%), 133 (22%), 117 (2.57%), 89 ( 0.40%).
From the above results, it was confirmed that the obtained compound was 2- (2- (2-methyl-2-adamantyloxy) -2-oxoethoxy) -2-oxoethanol.

[Synthesis Example 4] (Synthesis of 2- (2- (2-methyl-2-adamantyloxy) -2-oxoethoxy) -2-oxoethyl methacrylate (Compound 3))
To a 2 L three-necked flask equipped with a thermometer, a condenser and a stirrer was added 165 g (584 mmol) of 2- (2- (2-methyl-2-adamantyloxy) -2-oxoethoxy) -2-oxoethanol, 2000 mL of THF, Triethylamine 105 mL (754 mmol) and p-methoxyphenol 0.165 g (1000 ppm) were added and dissolved. After dissolution, 62.7 mL (648 mmol) of methacryloyl chloride was slowly added in an ice bath, warmed to room temperature, and stirred for 3 hours. After completion of the reaction, 1000 mL of diethyl ether was added and washed 5 times with 200 mL of distilled water. The extract was concentrated to obtain 198 g (yield 97%, GC purity 99%) of the target compound 3 as a colorless liquid.

The instrumental analysis results of the obtained compound 3 were as follows.
¹ H-NMR: 1.58 (d, J = 12.5 Hz, 2H), 1.63 (s, 3H), 1.71 to 1.89 (m, 8H), 1.98 (s, 3H) , 2.00 (m, 2H), 2.30 (m, 2H), 4.62 (s, 2H), 4.80 (s, 2H), 5.66 (m, 1H), 6.23 ( m, 1H).
¹³ C-NMR: 18.04, 22.15, 26.42, 27.14, 32.82, 34.38, 36.11, 37.92, 60.44, 61.28, 89.42, 126 79, 135.18, 165.61, 166.30, 167.20.
GC-MS: 350 (M +, 1.4%), 206 (0.13%), 149 (47%), 148 (100%), 133 (20%), 69 (37%).
From the above results, it was confirmed that the obtained compound 3 was 2- (2- (2-methyl-2-adamantyloxy) -2-oxoethoxy) -2-oxoethyl methacrylate.

[Synthesis Example 5] (Synthesis of polymer compound (1))
In a 500 mL beaker, 3.11 g (18.28 mmol) of the following [Compound 1], 11.99 g (45.71 mmol) of the following [Compound 2], and 6.40 g (18. 28 mmol) of the following [Compound 3] and 1.73 g (7.31 mmol) of the following [Compound 4] were added and dissolved in 108.96 g of methyl ethyl ketone. To this solution, 3.1 mmol of dimethyl azobisisobutyrate (V-601) was added as a polymerization initiator and dissolved. This reaction solution was added dropwise to 45.40 g of methyl ethyl ketone heated to 75 ° C. in a separable flask over 6 hours under a nitrogen atmosphere. After completion of dropping, the reaction solution was heated and stirred for 1 hour, and then the reaction solution was cooled to room temperature. The obtained reaction polymerization solution is concentrated under reduced pressure, then dropped into a large amount of methanol / water mixed solution, and the reaction product (copolymer) is precipitated. The precipitated reaction product is filtered, washed and dried. As a result, 15 g of the target polymer compound (1) was obtained.
With respect to this polymer compound (1), the mass average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement was 7,100, and the dispersity (Mw / Mn) was 1.59.
Moreover, as a result of measuring the carbon 13 nuclear magnetic resonance spectrum (600 MHz ¹³ C-NMR) at 600 MHz, the copolymer composition (ratio (molar ratio) of each structural unit in the above structural formula) was 1 / m / n / o = 24.9 / 31.9 / 28.7 / 14.5.

[Examples 2-3, Comparative Examples 1-2]
Each component shown in Table 1 was mixed and dissolved to prepare a positive resist composition.

In Table 1, the numerical values in [] indicate the blending amount (parts by mass). Moreover, the symbol in Table 1 shows the following, respectively.
(A) -1: a polymer compound represented by the following chemical formula (A1-11-1) [Mw: 10,000, Mw / Mn: 1.7]. In the formula, the number attached to the lower right of () indicates the ratio (molar ratio) of each structural unit.

(A) -2: The polymer compound (1).
(B) -1: a compound represented by the following chemical formula (b-3-1).

(B) -2: Compound (V).
(D) -1: tri-n-pentylamine.
(S) -1: PGMEA / PGME = 6/4 (mass ratio) mixed solvent.

Using the obtained resist composition, a resist pattern was formed by the following procedure, and the lithography characteristics were evaluated.
[Resolution and sensitivity]
An organic antireflection film composition “ARC29A” (trade name, manufactured by Brewer Science Co., Ltd.) is applied onto a 12-inch silicon wafer using a spinner and baked on a hot plate at 205 ° C. for 60 seconds to be dried. Thus, an organic antireflection film having a film thickness of 85 nm was formed.
Then, each of the above resist compositions is applied onto the antireflection film using a spinner, and prebaked (PAB) for 60 seconds under the PAB temperature conditions shown in Table 2 on a hot plate, followed by drying. A resist film having a thickness of 120 nm was formed.
Next, an ArF excimer laser (193 nm) is applied to the resist film using an ArF exposure apparatus NSR-S308F (Nikon Corp .; NA (numerical aperture) = 0.92), and a mask pattern (6% halftone mask). Selectively irradiated.
And the post-exposure heating (PEB) process for 60 second was performed on PEB temperature conditions shown in Table 2, and also 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution NMD-3 (brand name, Tokyo) at 23 degreeC. (Oka Kogyo Co., Ltd.) was subjected to alkali development for 30 seconds, then rinsed with pure water for 30 seconds, and then shaken and dried.
As a result, in each example, a line and space pattern (hereinafter referred to as “L / S pattern”) having a line width of 65 nm and a pitch of 130 nm was formed on the resist film.

[sensitivity]
In the formation of the resist pattern, the optimum exposure dose Eop (mJ / cm ² ; sensitivity) for forming an L / S pattern having a line width of 65 nm and a pitch of 130 nm was determined. The results are shown in Table 2.

[Evaluation of line width roughness (LWR)]
In the L / S pattern with a line width of 65 nm and a pitch of 130 nm formed by the Eop, the line width is adjusted in the longitudinal direction of the line by a length measuring SEM (scanning electron microscope, trade name: S-9220, manufactured by Hitachi, Ltd.). Five locations were measured, and from the result, a triple value (3 s) of the standard deviation (s) was calculated as a scale indicating LWR. The result is shown in Table 2 as 3L as “LWR”.
The smaller the value of 3s, the smaller the roughness of the line width, which means that a more uniform width L / S pattern was obtained.

  From the results of Table 2, in the resist composition used for evaluation, Example 2 has a lower LWR value than Comparative Example 1 and Example 3 has a lower LWR value than Comparative Example 2. It was confirmed that by using the composition, the roughness of the line width was small and an L / S pattern with a more uniform width was obtained.

  Therefore, according to the present invention, the lithographic properties such as LWR are improved, and the use of an acid generator that does not generate a PFAS compound as an acid generated by exposure improves the handleability in consideration of bioaccumulation. It was confirmed that a resist composition and a resist pattern forming method using the resist composition can be provided.

Claims (9)

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 said acid generator component (B) contains the acid generator (B1) which consists of a compound represented by the following general formula (b1-1), The resist composition characterized by the above-mentioned.

[Wherein Y ¹¹ is an optionally substituted fluorinated alkyl group having 1 to 4 carbon atoms, and Y ¹² is an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. Y ¹³ is a non-hydrocarbon oxygen atom-containing linking group selected from the group consisting of an oxygen atom, an ester bond, an amide bond, a carbonyl group, and a carbonate bond, and the non-hydrocarbon oxygen atom-containing linking group; A combination with an alkylene group (provided that the alkylene group is located on the X ¹⁰ side) or a single bond , and X ¹⁰ is a cyclic hydrocarbon group having 3 to 30 carbon atoms which may have a substituent. Yes; A ⁺ is an organic cation. ]   The resist composition according to claim 1, wherein the base component (A) is a base component whose solubility in an alkaline developer is increased by the action of an acid. The base 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) has a substituent bonded to the α-position carbon atom. the resist composition of claim 2, further comprising a acid dissociable, dissolution inhibiting group including configuration unit (a1) a structural unit which is also derived from an acrylate ester have. Wherein the resin component (A1) further a structural unit substituents α position carbon atom is derived from an acrylate ester which may be bonded lactone-containing cyclic group of including configuration unit (a2 The resist composition according to claim 3, which comprises: Wherein the resin component (A1) further, alpha-position polar group-containing aliphatic a structural unit which is also derived from an acrylate ester bonded substituent to a carbon atom of a hydrocarbon group including configure the The resist composition of Claim 3 or 4 which has a unit (a3).   The resist composition as described in any one of Claims 1-5 containing a nitrogen-containing organic compound component (D).   A step of forming a resist film on the support using the resist composition according to any one of claims 1 to 6, a step of exposing the resist film, and an alkali developing of the resist film to form a resist pattern A resist pattern forming method including a step of forming a film. The compound represented by the following general formula (b1-1).

[Wherein Y ¹¹ is an optionally substituted fluorinated alkyl group having 1 to 4 carbon atoms, and Y ¹² is an optionally substituted fluorinated alkylene group having 1 to 4 carbon atoms. Y ¹³ is a non-hydrocarbon oxygen atom-containing linking group selected from the group consisting of an oxygen atom, an ester bond, an amide bond, a carbonyl group, and a carbonate bond, and the non-hydrocarbon oxygen atom-containing linking group; A combination with an alkylene group (provided that the alkylene group is located on the X ¹⁰ side) or a single bond , and X ¹⁰ is a cyclic hydrocarbon group having 3 to 30 carbon atoms which may have a substituent. Yes; A ⁺ is an organic cation. ]   An acid generator comprising the compound according to claim 8.