JP6513899B2 - Resist composition and method for forming resist pattern - Google Patents

Description

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

In the lithography technique, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed to radiation such as light or electron beam through a mask on which a predetermined pattern is formed. And a development process is performed to form a resist pattern of a predetermined shape on the resist film.
A resist material in which the exposed portion changes to a property of being dissolved in the developer is referred to as a positive type, and a resist material in which the exposed portion is changed to a property not to be dissolved in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, miniaturization of patterns is rapidly progressing with advances in lithography technology.
Generally as a method of refinement | miniaturization, shortening of the wavelength (exposure) of the exposure light source is performed. Specifically, conventionally, ultraviolet rays represented 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 been started. In addition, electron beams with a wavelength (high energy) shorter than those of these excimer lasers, EUV (extreme ultraviolet), X-rays, and the like are also being studied.

The resist material is required to have such lithography characteristics as sensitivity to the exposure light source and resolution capable of reproducing a pattern of fine dimensions.
Conventionally, as a resist material satisfying such requirements, a chemically amplified resist composition comprising a base component whose solubility in a developer changes due to the action of an acid, and an acid generator component that generates an acid upon exposure to light It is used. For example, when the developer is an alkali developer (alkali development process), as a positive-working chemically amplified resist composition, a resin component (base resin) whose solubility in an alkali developer increases by the action of an acid, and an acid Those containing a generator component are generally used. When a resist film formed using such a resist composition is selectively exposed at the time of forming a resist pattern, an acid is generated from the acid generator component in the exposed portion, and the polarity of the base resin is increased by the action of the acid. As a result, the exposed portion becomes soluble in the alkali developer. Therefore, by performing alkali development, a positive pattern in which unexposed portions remain as a pattern is formed. On the other hand, when a solvent development process using a developing solution containing an organic solvent (organic developing solution) is applied, the solubility in the organic developing solution is relatively lowered when the polarity of the base resin is increased. The unexposed area is dissolved and removed by the organic developer to form a negative resist pattern in which the exposed area remains as a pattern. Such a solvent development process for forming a negative resist pattern may be referred to as a negative development process (Patent Document 1).

  The base resin used in the chemically amplified resist composition generally has a plurality of structural units in order to improve the lithography properties and the like. For example, in the case of a resin component in which the solubility in an alkali developing solution is increased by the action of an acid, a structural unit containing an acid degradable group which is decomposed by the action of an acid generated from an acid generator is used. In addition to the above, a structural unit containing a lactone-containing cyclic group, a structural unit containing a polar group such as a hydroxyl group, and the like are used (see, for example, Patent Document 2).

JP, 2009-025723, A Unexamined-Japanese-Patent No. 2003-241385

  In recent years, with the progress of miniaturization of patterns, polymer compounds useful as a base resin for resist compositions are required to have high sensitivity and improvement of various lithography properties. Although various lithography properties can be improved by shortening the diffusion length of the acid generated from the acid generator contained in the resist composition, this method has a disadvantage that the sensitivity is lowered.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist composition which is high in sensitivity and excellent in lithography characteristics.

In the present specification and claims, “aliphatic” is a concept relative to an aromatic and is defined to mean a group, a compound or the like having no aromaticity.
The term "alkyl group" is intended to include linear, branched and cyclic monovalent saturated hydrocarbon groups, unless otherwise specified.
The "alkylene group" is intended to include a linear, branched and cyclic divalent saturated hydrocarbon group unless otherwise specified. The same applies to the alkyl group in the alkoxy group.
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.
The "fluorinated alkyl group" or "fluorinated alkylene group" refers to a group in which part or all of the hydrogen atoms of the alkyl group or the alkylene group are substituted with a fluorine atom.
The "constituent unit" means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).
The “constituent unit derived from acrylic acid ester” means a constitutional unit formed by cleavage of the ethylenic double bond of acrylic acid ester.
The “acrylic ester” is a compound in which the hydrogen atom at the carboxy group terminal of acrylic acid (CH ₂ = CH—COOH) is substituted with an organic group.
In the acrylic ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted by a substituent. The substituent (R ^α ) for substituting the hydrogen atom bonded to the carbon atom at the α-position is an atom or a group other than a hydrogen atom, and is, for example, an alkyl group of 1 to 5 carbon atoms, a halogenation of 1 to 5 carbon atoms Alkyl groups, hydroxyalkyl groups and the like can be mentioned. In addition, the carbon atom of alpha-position of acrylic acid ester is a carbon atom which the carbonyl group has couple | bonded, unless there is particular notice.
Hereinafter, an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α position is substituted with a substituent may be referred to as an α-substituted acrylic acid ester. Moreover, an acrylic ester and an alpha substituted acrylic ester may be included and it may be called "(alpha substituted) acrylic ester."
The “structural unit derived from hydroxystyrene or a hydroxystyrene derivative” means a structural unit formed by cleavage of an ethylenic double bond of hydroxystyrene or a hydroxystyrene derivative.
The term "hydroxystyrene derivative" is a concept including those in which a hydrogen atom at the alpha position of hydroxystyrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As their derivatives, those in which the hydrogen atom of hydroxystyrene which may be substituted with a hydrogen atom at the alpha position is substituted with an organic group, or even if the hydrogen atom at the alpha position is substituted with a substituent What has substituents other than a hydroxyl group couple | bonded with the benzene ring of good hydroxystyrene, etc. are mentioned. The alpha position (carbon atom at the alpha position) refers to the carbon atom to which the benzene ring is bonded unless otherwise specified.
As a substituent which substitutes the hydrogen atom of alpha position of hydroxystyrene, the thing similar to what was mentioned as a substituent of alpha position in the above-mentioned alpha substitution acrylic acid ester is mentioned.
The “constituent unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative” means a constitutional unit formed by cleavage of an ethylenic double bond of vinylbenzoic acid or a vinylbenzoic acid derivative.
The "vinyl benzoic acid derivative" is a concept including those in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with an alkyl group, another substituent such as a halogenated alkyl group, and derivatives thereof. As their derivatives, those in which the hydrogen atom in the alpha position is substituted with an organic group and the hydrogen atom in the carboxy group of vinyl benzoic acid which may be substituted with a substituent, or the hydrogen atom in the alpha position is substituted with a substituent And those in which a substituent other than a hydroxyl group and a carboxy group is bonded to the benzene ring of vinyl benzoic acid which may be mentioned. The alpha position (carbon atom at the alpha position) refers to the carbon atom to which the benzene ring is bonded unless otherwise specified.
The term "styrene derivative" is a concept including one in which a hydrogen atom at the alpha position of styrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group.
The “structural unit derived from styrene” and the “structural unit derived from a styrene derivative” mean a structural unit formed by cleavage of an ethylenic double bond of styrene or a styrene derivative.
The alkyl group as a substituent at the α-position is preferably a linear or branched alkyl group, and specifically, an alkyl group having 1 to 5 carbon atoms (a methyl group, an ethyl group, a propyl group, an isopropyl group) , N-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.
In addition, specific examples of the halogenated alkyl group as a substituent at the α-position include groups in which part or all of the hydrogen atoms of the above “alkyl group as a substituent at the α-position” are substituted with a halogen atom Be 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.
Further, specific examples of the hydroxyalkyl group as a substituent at the α-position include groups in which part or all of the hydrogen atoms of the above-mentioned “alkyl group as a substituent at the α-position” are substituted with a hydroxyl group. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.
When it is described that "it may have a substituent", when substituting a hydrogen atom (-H) with a monovalent group and when substituting a methylene group (-CH _2- ) with a divalent group Including both.
"Exposure" is a concept that includes general radiation irradiation.

  The first aspect of the present invention is a resist composition which generates an acid by exposure to light and changes the solubility in a developer by the action of the acid, and the base material changes the solubility in the developer by the action of an acid. Component (A) and an acid generator component (B) that generates an acid upon exposure to light, the base material component (A) comprising a structural unit (a0) represented by the following general formula (a0-1) A resist composition comprising the polymer compound (A1) having the acid generator component (B), and the acid generator component (B) containing a compound represented by the following general formula (b-1) or (b-2) .

［式（ａ０−１）中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基、Ｙａ^０１は２価の連結基、Ｚａ^０１はＸａ^０１に結合する炭素原子と共に炭素数３〜２０の２価の脂環式基を形成する基、Ｘａ^０１は炭素数１〜６の直鎖状又は分岐鎖状のアルキレン基、Ｒａ^０１は炭素数１〜１０の脂肪族炭化水素基、ｎは０〜２である。］

[In the formula (a0-1), R represents a hydrogen atom, an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms, Ya ⁰¹ is a divalent linking group, and Za ⁰¹ is bonded to Xa ⁰¹ Xa ⁰¹ is a linear or branched alkylene group having 1 to 6 carbon atoms, and Ra ⁰¹ is a group having 1 to 10 carbon atoms. Aliphatic hydrocarbon group, n is 0 to 2; ]

［式（ｂ−１）及び（ｂ−２）中、Ｒ^１０１は置換基を有していてもよい環式基である。Ｒ^１０４、Ｒ^１０５は、それぞれ独立に置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基であり、相互に結合して環を形成していてもよい。Ｒ^１０４、Ｒ^１０５の少なくとも一方は置換基を有していてもよい環式基である。Ｒ^１０２はフッ素原子または炭素数１〜５のフッ素化アルキル基である。Ｙ^１０１は単結合または酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３はそれぞれ独立に単結合、アルキレン基、またはフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２はそれぞれ独立に単結合または酸素原子である。ｍは１以上の整数であって、Ｍ’^ｍ＋はｍ価の有機カチオンである。］

[In Formula (b-1) and (b-2), R ¹⁰¹ is a cyclic group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ each independently represent a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain which may have a substituent And the alkenyl group may be bonded to each other to form a ring. At least one of R ¹⁰⁴ and R ¹⁰⁵ is a cyclic group which may have a substituent. R ¹⁰² is a fluorine atom or a fluorinated alkyl group of 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ^{101 to} V ¹⁰³ each independently represent a single bond, an alkylene group, or a fluorinated alkylene group. L ^{101 to} L ¹⁰² each independently represent a single bond or an oxygen atom. m is an integer of 1 or more, and M ' ^{m +} is an m-valent organic cation. ]

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

  According to the present invention, it is possible to provide a resist composition which is high in sensitivity and excellent in lithography characteristics.

«Resist composition»
The resist composition of the present invention is a resist composition which generates an acid upon exposure to light and changes the solubility in a developer by the action of the acid, and the base component the solubility in the developer changes by the action of an acid (A) and an acid generator component (B) which generates an acid upon exposure to light, wherein the base component (A) has a structural unit (a0) represented by the general formula (a0-1) The acid generator component (B) contains a molecular compound (A1), and the acid generator component (B) contains a compound represented by the general formula (b-1) or (b-2).

The resist composition according to the first aspect of the present invention is a resist composition in which an acid is generated by exposure to light, and the solubility in a developer is changed by the action of the acid, and the solubility in the developer is changed by the action of an acid. The base component (A) (hereinafter referred to as "component (A)") is contained.
When a resist film is formed using this resist composition, and the resist film is selectively exposed, an acid is generated in the exposed area, and the acid acts to dissolve the component (A) in the developer. While changing, in the unexposed area, the solubility of the component (A) in the developer does not change, so that a difference in solubility in the developer occurs between the exposed area and the unexposed area. Therefore, when the resist film is developed, the exposed area is dissolved and removed to form a positive resist pattern when the resist composition is positive, and the unexposed area is dissolved and removed when the resist composition is negative. Thus, a negative resist pattern is formed.
In this specification, a resist composition in which an exposed part is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition in which a non-exposed part is dissolved and removed to form a negative resist pattern. Is referred to as a negative resist composition.
The resist composition of the present invention may be a positive resist composition or a negative resist composition.
Further, the resist composition of the present invention may be for an alkaline development process using an alkaline developer for development at the time of resist pattern formation, and the development may be a developer (organic developer) containing an organic solvent. It may be for the solvent development process used.

The resist composition of the present invention has an acid generating ability to generate an acid upon exposure, and the component (A) may generate an acid upon exposure, and the additive component formulated separately from the component (A) May generate an acid upon exposure.
Specifically, the resist composition of the present invention may contain (1) an acid generator component (B) (hereinafter referred to as "component (B)") that generates an acid upon exposure to light. (2) The component (A) may be a component that generates an acid upon exposure; (3) the component (A) is a component that generates an acid upon exposure, and further contains a component (B) It may be one.
That is, in the case of the above (2) and (3), the component (A) becomes “a base component which generates an acid upon exposure and whose solubility in a developer changes by the action of the acid”. When the component (A) is a base component which generates an acid upon exposure and the solubility in a developer changes due to the action of the acid, the component (A1) described later generates an acid upon exposure, and It is preferable that it is a polymer compound whose solubility in a developer changes by action. As such a polymer compound, a resin having a structural unit that generates an acid upon exposure can be used. Known structural units can be used as structural units that generate an acid upon exposure.
In the resist composition of the present invention, the case of the above (1) is particularly preferable.

  In the resist composition of the present invention, the base component (A) contains the polymer compound (A1) having the structural unit (a0) represented by the general formula (a0-1), and generates a short diffusion acid. By containing an acid generator, it is possible to achieve high sensitivity while maintaining good lithography properties.

<(A) component>
The resist composition of the present embodiment preferably contains a base component (A) whose solubility in a developer changes due to the action of an acid.
In the present invention, the “base component” is an organic compound having film forming ability, preferably an organic compound having a molecular weight of 500 or more. When the molecular weight of the organic compound is 500 or more, the film forming ability is improved, and in addition, it is easy to form a nano-level resist pattern.
Organic compounds used as a base component are roughly classified into non-polymers and polymers.
As the non-polymer, one having a molecular weight of 500 or more and less than 4,000 is usually used. Hereinafter, the term "low molecular weight compound" refers to a non-polymer having a molecular weight of 500 or more and less than 4,000.
As the polymer, one having a molecular weight of 1,000 or more is usually used. Hereinafter, the term "resin" refers to a polymer having a molecular weight of 1000 or more.
As a molecular weight of a polymer, the weight average molecular weight of polystyrene conversion by GPC (gel permeation chromatography) shall be used.
As the component (A), a resin may be used, a low molecular weight compound may be used, and these may be used in combination.
The component (A) may be one in which the solubility in a developer increases by the action of an acid, and the one in which the solubility in a developer decreases by the action of an acid.
In the present invention, the component (A) may generate an acid upon exposure.

  In the resist composition of the present invention, the base component (A) contains a polymer compound (A1) having a structural unit (a0) represented by the following general formula (a0-1).

［式（ａ０−１）中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基、Ｙａ^０１は２価の連結基、Ｚａ^０１はＸａ^０１に結合する炭素原子と共に炭素数３〜２０の２価の脂環式基を形成する基、Ｘａ^０１は炭素数１〜６の直鎖状又は分岐鎖状のアルキレン基、Ｒａ^０１は炭素数１〜１０の脂肪族炭化水素基、ｎは０〜２である。］

[In the formula (a0-1), R represents a hydrogen atom, an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms, Ya ⁰¹ is a divalent linking group, and Za ⁰¹ is bonded to Xa ⁰¹ Xa ⁰¹ is a linear or branched alkylene group having 1 to 6 carbon atoms, and Ra ⁰¹ is a group having 1 to 10 carbon atoms. Aliphatic hydrocarbon group, n is 0 to 2; ]

R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group in said general formula (a0-1).
The alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group , Isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with a halogen atom. 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.
As R, a hydrogen atom, an alkyl group of 1 to 5 carbon atoms, or a fluorinated alkyl group of 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable in terms of industrial availability.

In the general formula (a0-1), Ya ⁰¹ is a divalent linking group. The divalent linking group is not particularly limited, and preferred examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group containing a hetero atom.

(Divalent hydrocarbon group which may have a substituent)
The hydrocarbon group as a divalent linking group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group containing a ring in the structure thereof. The group illustrated by Va ¹ in 1) is mentioned.

  The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group of 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

As the aliphatic hydrocarbon group containing a ring in the above structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (2 hydrogen atoms are removed from an aliphatic hydrocarbon ring) Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is a linear or branched fatty acid And the like interposed in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as described above.
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, specifically include groups exemplified in Va ¹ in the formula (a1-1) described below.
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like.
The alkyl group as the substituent is preferably an alkyl group having a carbon number of 1 to 5, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having a carbon number of 1 to 5, and is preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group, methoxy And ethoxy groups are most preferred.
As a halogen atom as the said substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned, A fluorine atom is preferable.
As a halogenated alkyl group as said substituent, the group by which one part or all part of the hydrogen atom of the said alkyl group was substituted by the said halogen atom is mentioned.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. The substituent containing a hetero atom, -O -, - C (= O) -O -, - S -, - S (= O) 2 -, - S (= O) 2 -O- are preferred.

Examples of the aromatic hydrocarbon group as the divalent hydrocarbon group, specifically include groups exemplified in Va ¹ in the formula (a1-1) described below.
In the aromatic hydrocarbon group, the hydrogen atom of the aromatic hydrocarbon group may be substituted by a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted by a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group and the like.
The alkyl group as the substituent is preferably an alkyl group having a carbon number of 1 to 5, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.
As the alkoxy group, the halogen atom and the halogenated alkyl group as the substituent, those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group can be mentioned.

(Divalent linking group containing hetero atom)
The hetero atom in the divalent linking group containing a hetero atom is an atom other than a carbon atom and a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom and the like.

When Ya ⁰¹ is a divalent linking group containing a hetero atom, preferred as the linking group are —O—, —C (= O) —O—, —C (= O) —, —O—C. (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group _{.), - S -, -} S (= O) 2 -, - S (= O) 2 -O-, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 - A group represented by C (= O) —O—, — [Y ²¹ —C (= O) —O] _{m ′} —Y ²² — or —Y ²¹ —O—C (= O) —Y ²² — wherein, Y ²¹ and Y ²² are each independently may be substituted divalent hydrocarbon group, O is an oxygen atom, m 'is an integer of 0 to 3. Etc.
When the divalent linking group containing a hetero atom is —C (= O) —NH—, —NH—, —NH—C (= NH) —, H is a substituent such as an alkyl group or acyl. It may be substituted. The substituent (such as an alkyl group or an acyl group) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - [Y 21 -C (= O) -O] m '-Y 22 - Or in —Y ²¹ —O—C (OO) —Y ²² —, each of Y ²¹ and Y ²² independently is a divalent hydrocarbon group which may have a substituent. As this bivalent hydrocarbon group, the thing similar to "the bivalent hydrocarbon group which may have a substituent" mentioned by the description as said bivalent coupling group is mentioned.
As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group or an ethylene group is particularly preferable preferable.
As Y ²² , a linear or branched aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group or an alkylmethylene group is more preferable. The alkyl group in the alkylmethylene group is preferably a linear alkyl group of 1 to 5 carbon atoms, more preferably a linear alkyl group of 1 to 3 carbon atoms, and most preferably a methyl group.
Formula ^{- [Y 21 -C (= O} ) -O] m '-Y 22 - In the group represented by, m' is an integer of 0 to 3, preferably an integer of 0 to 2, 0 Or 1 is more preferable, and 1 is particularly preferable. In other words, the formula ^- Examples of the group represented by the formula ^{-Y 21 -C (= O) -O} -Y 22 - - [Y 21 -C (= O) -O] m '-Y 22 represented by Groups are particularly preferred. Among them, the formula _{- (CH 2) a '-C} (= O) -O- (CH 2) b' - a group represented by are preferred. In the formula, a 'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1.

Ya ⁰¹ in the present invention is a single bond, or an ester bond [—C (= O) —O—], an ether bond (—O—), a linear or branched alkylene group, or a combination thereof Is preferred.

  In the general formula (a0-1), n is an integer of 0 to 2, preferably 0 or 1.

In the general formula (a0-1), Za ⁰¹ is a group forming a divalent alicyclic group having 3 to 20 carbon atoms together with the carbon atom bonded to Xa ⁰¹ . The divalent cyclic group formed together with the carbon atom bonded to Xa ⁰¹ includes two cycloalkanes such as cyclopentane, cyclohexane, cycloheptane, cyclooctane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like The alicyclic group except the above hydrogen atom is mentioned.
In the present invention, examples of the divalent cyclic group formed together with the carbon atom bonded to Xa ^01, cyclopentane, cyclohexane, cycloheptane, cyclooctane or adamantane are preferred, and more preferably cyclopentane.

In the general formula (a0-1), Xa ⁰¹ is a linear or branched alkylene group having 1 to 6 carbon atoms.
Specific examples of the linear alkylene group include methylene group [-CH _2- ], ethylene group [-(CH ₂ ) _2- ], trimethylene group [-(CH ₂ ) _3- ] and tetramethylene group. _{[- (CH 2) 4 -} ], a pentamethylene group _{[- (CH 2) 5 -} ] , and the like.
Preferably branched alkylene group, _{specifically, -CH (CH 3) -,} - CH (CH 2 CH 3) -, - C (CH 3) 2 -, - C (CH 3) (CH 2 Alkylmethylene groups such as CH ₃ ) —, —C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) —, —C (CH ₂ CH ₃ ) ₂ — and the like; —CH (CH ₃ ) CH ₂ —, —CH ( _{CH 3) CH (CH 3)} -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - C (CH 2 CH 3) 2 -CH 2 - alkyl ethylene such as _{group; -CH (CH 3) CH 2} CH 2 -, - CH 2 CH (CH 3) CH 2 - alkyl trimethylene groups such _{as; -CH (CH 3) CH 2} CH 2 CH 2 -, - CH 2 CH a such as an alkyl tetramethylene group such as _{- (CH 3) CH 2 CH} 2 Kiruarukiren group, and the like.
In the present invention, when Xa ⁰¹ is a linear alkylene group, it is preferably a methylene group or an ethylene group, and when it is a branched alkylene group, —CH (CH ₃ ) ( CH ₂₎ - it is preferably.

In the above general formula (a0-1), Ra ⁰¹ is a C 1-10 aliphatic hydrocarbon group.
As a linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH _2- ], an ethylene group [-(CH ₂ ) _2- ], a trimethylene group [ _{- (CH 2) 3 -]} , a tetramethylene group _{[- (CH 2) 4 -} ], a pentamethylene group _{[- (CH 2) 5 -} ] , and the like.
As the branched aliphatic hydrocarbon group, preferably a branched chain alkylene group, _{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 -, - C (CH 2 An alkylethylene group such as CH ₃ ) ₂ -CH _2- ; an alkyltrimethylene group such as -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH _2-, etc .; -CH (CH ₃ ) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. As an alkyl group in an alkyl alkylene group, a C1-C5 linear alkyl group is preferable.

  Specific examples of the structural unit (a0) are shown below. In each of the following formulas, R is as defined above.

  20-80 mol% is preferable with respect to all the structural units which comprise (A) component, and, as for the ratio of the structural unit (a0) in (A) component, 20-75 mol% is more preferable, and 20-70 mol% Is more preferred. By setting the value to the lower limit value or more, lithography properties such as sensitivity and LWR are also improved. Further, by setting the upper limit value or less, it is possible to balance with other constituent units.

The structural unit (a0) is an acid dissociable monomer having a polar site. Since the oxygen atom in -Xa ⁰¹ -O-Ra ⁰¹ in the general formula (a0-1) has affinity to protons, for example, when an alkaline developer is used, the affinity with the developer is enhanced, and high It is thought that it can contribute to sensitivity.

In the present embodiment, the polymer compound (A1) preferably has a structural unit (a2) containing a lactone-containing cyclic group or a —SO ₂ -containing cyclic group.

(Constituent unit (a2))
The structural unit (a2) is a structural unit containing a lactone-containing cyclic group or a —SO ₂ -containing cyclic group.
The lactone-containing cyclic group of the structural unit (a2) is effective in enhancing the adhesion of the resist film to the substrate when the component (A1) is used to form a resist film.
When the structural unit (a1) described later contains a lactone-containing cyclic group or a —SO ₂ —containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a2), A structural unit corresponds to the structural unit (a1) and does not correspond to the structural unit (a2).
The —SO ₂ — containing cyclic group of the structural unit (a2) is effective in enhancing the adhesion of the resist film to the substrate when the component (A1) is used for the formation of the resist film.
When the structural unit (a1) to be described later contains an —SO ₂ — containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a2), but such a structural unit is a structural unit It corresponds to (a1) and does not correspond to the structural unit (a2).

  The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｙａ^２１は単結合または２価の連結基であり、Ｌａ^２１は−Ｏ−、−ＣＯＯ−、−ＯＣＯ−である。ただしＬａ^２１が−Ｏ−の場合、Ｙａ^２１は−ＣＯ−にはならない。Ｒａ^２１はラクトン含有環式基、カーボネート含有環式基、又は−ＳＯ_２−含有環式基である。］

Wherein R is a hydrogen atom, an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms, Ya ²¹ is a single bond or a divalent linking group, and La ²¹ is —O -, -COO-, -OCO-. However, when La ²¹ is —O—, Ya ²¹ does not become —CO—. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group, or a —SO ₂ -containing cyclic group. ]

The divalent linking group for Ya ²¹ is not particularly limited, and preferred examples thereof include a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like.

(Divalent hydrocarbon group which may have a substituent)
The hydrocarbon group as a divalent linking group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group containing a ring in the structure thereof. The group illustrated by Va ¹ in 1) is mentioned.

  The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group of 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

As the aliphatic hydrocarbon group containing a ring in the above structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (2 hydrogen atoms are removed from an aliphatic hydrocarbon ring) Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is a linear or branched fatty acid And the like interposed in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as described above.
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, specifically include groups exemplified in Va ¹ in the aforementioned formula (a1-1).
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group and the like.
The alkyl group as the substituent is preferably an alkyl group having a carbon number of 1 to 5, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having a carbon number of 1 to 5, and is preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group, methoxy And ethoxy groups are most preferred.
As a halogen atom as the said substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned, A fluorine atom is preferable.
As a halogenated alkyl group as said substituent, the group by which one part or all part of the hydrogen atom of the said alkyl group was substituted by the said halogen atom is mentioned.
In the cyclic aliphatic hydrocarbon group, a part of carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. The substituent containing a hetero atom, -O -, - C (= O) -O -, - S -, - S (= O) 2 -, - S (= O) 2 -O- are preferred.

Examples of the aromatic hydrocarbon group as the divalent hydrocarbon group, specifically include exemplified groups Va ¹ in the aforementioned formula (a1-1).
In the aromatic hydrocarbon group, the hydrogen atom of the aromatic hydrocarbon group may be substituted by a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted by a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group and the like.
The alkyl group as the substituent is preferably an alkyl group having a carbon number of 1 to 5, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.
As the alkoxy group, the halogen atom and the halogenated alkyl group as the substituent, those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group can be mentioned.

(Divalent linking group containing hetero atom)
The hetero atom in the divalent linking group containing a hetero atom is an atom other than a carbon atom and a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom and the like.

When Ya ²¹ is a divalent linking group containing a hetero atom, preferred as the linking group are —O—, —C (= O) —O—, —C (= O) —, —O—C. (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group _{.), - S -, -} S (= O) 2 -, - S (= O) 2 -O-, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 - ^{C (= O) -O -,} - C (= O) -O-Y 21, - [Y 21 -C (= O) -O] m '-Y 22 - or ^-Y 21 -O-C (= A group represented by the formula O) -Y ^22-wherein Y ²¹ and Y ²² each independently represent a divalent hydrocarbon group which may have a substituent, and O is an oxygen atom, m 'is an integer of 0-3. Etc.
When the divalent linking group containing a hetero atom is —C (= O) —NH—, —NH—, —NH—C (= NH) —, H is a substituent such as an alkyl group or acyl. It may be substituted. The substituent (such as an alkyl group or an acyl group) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - C (= O) -O-Y 21 -, - [Y 21 -C _{(= O) -O] m '} -Y 22 - or ^{-Y 21 -O-C (= O} ) -Y 22 - ^{in, Y 21} and ^{Y 22} each independently have a substituent It is also a good bivalent hydrocarbon group. As this bivalent hydrocarbon group, the thing similar to "the bivalent hydrocarbon group which may have a substituent" mentioned by the description as said bivalent coupling group is mentioned.
As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group or an ethylene group is particularly preferable preferable.
As Y ²² , a linear or branched aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group or an alkylmethylene group is more preferable. The alkyl group in the alkylmethylene group is preferably a linear alkyl group of 1 to 5 carbon atoms, more preferably a linear alkyl group of 1 to 3 carbon atoms, and most preferably a methyl group.
Formula ^{- [Y 21 -C (= O} ) -O] m '-Y 22 - In the group represented by, m' is an integer of 0 to 3, preferably an integer of 0 to 2, 0 Or 1 is more preferable, and 1 is particularly preferable. In other words, the formula ^- Examples of the group represented by the formula ^{-Y 21 -C (= O) -O} -Y 22 - - [Y 21 -C (= O) -O] m '-Y 22 represented by Groups are particularly preferred. Among them, the formula _{- (CH 2) a '-C} (= O) -O- (CH 2) b' - a group represented by are preferred. In the formula, a 'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1. b ′ is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1.

In the present invention, Ya ²¹ is a single bond, or an ester bond [—C (= O) —O—], an ether bond (—O—), a linear or branched alkylene group, or a combination thereof Is preferred.

In the above formula (a2-1), Ra ²¹ is a lactone-containing cyclic group or a —SO ₂ — containing cyclic group.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing —O—C (= O) — in the ring skeleton thereof. The lactone ring is counted as the first ring, and when it has only a lactone ring, it is a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of its structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group is not particularly limited, and any group can be used. Specifically, groups represented by general formulas (a2-r-1) to (a2-r-7) shown below can be mentioned. Hereinafter, "*" represents a bond.

［式中、Ｒａ’^２１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；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り、ｎ’は０〜２の整数であり、ｍ’は０または１である。］

Wherein, Ra ^'21 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxyl group, -COOR - in ", OC (= O) R ", a hydroxyalkyl group or a cyano group R ′ ′ is a hydrogen atom or an alkyl group; A ′ ′ is an oxygen atom or an alkylene group having 1 to 5 carbon atoms which may contain a sulfur atom, an oxygen atom or a sulfur atom, and n ′ is 0 to 2 And m 'is 0 or 1. ]

In the general formulas (a2-r-1) to (a2-r-7), A ′ ′ is an oxygen atom (—O—) or a sulfur atom (—S—) and may have 1 to 5 carbon atoms As the alkylene group having 1 to 5 carbon atoms in A ′ ′, a linear or branched alkylene group is preferable, and a methylene group, an ethylene group, an n-propylene group, An isopropylene group etc. are mentioned. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which —O— or —S— intervenes in the terminal of the alkylene group or between carbon atoms, such as —O—CH _{2 -, - CH 2 -O-CH} 2 -, - S-CH 2 -, - CH 2 -S-CH 2 - , and the like. As A ′ ′, an alkylene group of 1 to 5 carbon atoms or —O— is preferable, an alkylene group of 1 to 5 carbon atoms is more preferable, and a methylene group is most preferable.

In the general formula (a2-r-1) ~ (a2-r-7), the alkyl group in Ra ^'21, preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group and the like can be mentioned. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.
The alkoxy group in the ra ^'21, preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, groups of the the Ra 'group and an oxygen atom mentioned as the alkyl group in ²¹ (-O-) are linked and the like.
As the halogen atom in ra ^'21, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom is preferable.
'Examples of the halogenated alkyl group for ^21, the Ra' Ra part or all of the hydrogen atoms of the alkyl group in ²¹ can be mentioned it has been substituted with the aforementioned halogen atoms. The halogenated alkyl group is preferably a fluorinated alkyl group, particularly preferably a perfluoroalkyl group.

Ra '-COOR in ^{21 ", - OC (= O} ) R" in, R "is also hydrogen either is an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ₂ - containing cyclic group It is.
The alkyl group in R ′ ′ may be linear, branched or cyclic, and preferably has 1 to 15 carbon atoms.
When R ′ ′ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group. preferable.
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 obtained by removing one or more hydrogen atoms from a monocycloalkane which may or may not be substituted with a fluorinated alkyl group; polycycloalkanes such as bicycloalkanes, tricycloalkanes and tetracycloalkanes Groups in which one or more hydrogen atoms have been removed, etc. More specifically, groups in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane, cyclohexane and the like; adamantane, norbornane, isobornane, tri Groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as cyclodecane and tetracyclododecane That.
Examples of the lactone-containing cyclic group in R ′ ′ include the same as the groups represented by the general formulas (a2-r-1) to (a2-r-7).
The carbonate-containing cyclic group in R ′ ′ is the same as the later-described carbonate-containing cyclic group, and specifically, groups represented by general formulas (ax3-r-1) to (ax3-r-3) Can be mentioned.
The containing cyclic group, -SO ₂ below - - -SO ₂ in R "are the same as containing cyclic group, specifically the general formula (a5-r-1) ~ (a5-r-4) And the groups respectively represented by

The hydroxyalkyl group in Ra ′ ²¹ is preferably one having 1 to 6 carbon atoms, and specific examples include a group in which at least one of the hydrogen atoms of the alkyl group in Ra ′ ²¹ is substituted with a hydroxyl group .
In the above general formulas (a2-r-2), (a2-r-3) and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A ′ ′ is linear or branched. An alkylene group is preferable, and examples thereof include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, etc. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include the terminal or carbon of the alkylene group. between atoms -O- or -S- can be mentioned a group intervening, for example, _{-O-CH 2 -, - CH} 2 -O-CH 2 -, - S-CH 2 -, - CH 2 -S-CH _2- "etc. is mentioned. As A", a C1-C5 alkylene group or -O- is preferable, a C1-C5 alkylene group is more preferable, and a methylene group is the most preferable.

  The specific example of group represented by general formula (a2-r-1)-(a2-r-7) below is given.

And _- "-SO 2 containing cyclic group", -SO 2 _- within the ring skeleton thereof shows a cyclic group containing a ring containing, in particular, -SO 2 _- sulfur atom (S) is in It is a cyclic group that forms a part of the ring skeleton of the cyclic group. The ring containing -SO _{2-in the} ring skeleton is counted as the first ring, and in the case of only this ring, it is a monocyclic group, and in the case of having another ring structure, a polycyclic group regardless of its structure It is called. The —SO ₂ -containing cyclic group may be monocyclic or polycyclic.
The —SO ₂ -containing cyclic group as cyclic hydrocarbon group is in particular a cyclic group containing —O—SO ₂ — in its ring skeleton, ie —O—S _{2 in} —O—SO ₂ — It is preferable that is a cyclic group containing a sultone ring which forms a part of a ring skeleton. More specifically, examples of the -SO ₂ -containing cyclic group include groups represented by general formulas (a5-r-1) to (a5-r-4) shown below.

［式中、Ｒａ’^５１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；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り、ｎ’は０〜２の整数である。］

[Wherein, each of Ra ^'51 is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR ", -OC (= O) R", a hydroxyalkyl group or a cyano group R ′ ′ is a hydrogen atom or an alkyl group; A ′ ′ is an oxygen atom or an alkylene group having 1 to 5 carbon atoms which may contain a sulfur atom, an oxygen atom or a sulfur atom, and n ′ is 0 to 2 Is an integer of ]

In the general formulas (a5-r-1) to (a5-r-4), A ′ ′ is the same as A ′ ′ in the general formulas (a2-r-1) to (a2-r-7). Alkyl group in ra ^'51, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR ", - OC (= O) R", The hydroxyalkyl group, the formula (a2-r-1) ~ (a2 it is the same as Ra ^'21 of -r-7) in.

  Specific examples of the groups represented by formulas (a5-r-1) to (a5-r-4) will be given below. "Ac" in a formula shows an acetyl group.

Among the above, the group represented by the general formula (a5-r-1) is preferable as the -SO ₂ -containing cyclic group, and the chemical formula (r-sl-1-1) or (r-sl-) is preferable. It is more preferable to use at least one selected from the group consisting of a group represented by any of 1-18), (r-sl-3-1) and (r-sl-4-1), and the chemical formula The group represented by (r-sl-1-1) is most preferable.

Among the above, lactone-containing cyclic group or -SO ₂ -containing cyclic group is preferable, and is represented by the general formula (a2-r-1), (a2-r-2) or (a5-r-1). Groups are preferred, and the above chemical formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-13), (r- The group of any of sl-1-1) and (r-sl-1-18) is more preferable.

The structural unit (a2) contained in the component (A1) may be one type or two or more types.
When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 1 to 80 mol% with respect to the total of all structural units constituting the component (A1) The content is more preferably 5 to 75 mol%, further preferably 10 to 70 mol%, and particularly preferably 20 to 70 mol%. By setting the content to the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by setting the content to the upper limit value or less, balance with other structural units can be achieved. The lithography properties and pattern shape of the

  In the present invention, the polymer compound (A1) further includes a constituent unit (a1) which is a constituent unit containing an acid degradable group whose polarity is increased by the action of an acid, and a constituent unit containing a polar group-containing aliphatic hydrocarbon group. The structural unit (a4) may have a structural unit (a4) containing a non-acid dissociable cyclic group and a structural unit (a9).

(Constituent unit (a1))
The structural unit (a1) is a structural unit containing an acid-degradable group whose polarity is increased by the action of an acid.
The "acid-degradable group" is a group having acid-degradability which can cleave at least a part of bonds in the structure of the acid-degradable group by the action of an acid.
Examples of the acid-degradable group whose polarity is increased by the action of an acid include, for example, a group which is decomposed by the action of an acid to generate a polar group.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, a sulfo group _(-SO 3 H) and the like. Among these, a polar group containing -OH in the structure (hereinafter sometimes referred to as "OH-containing polar group") is preferable, a carboxy group or a hydroxyl group is preferable, and a carboxy group is particularly preferable.
More specifically, examples of the acid-degradable group include groups in which the polar group is protected by an acid dissociative group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid dissociative group).
Here, the "acid dissociable group" is
(I) A group having an acid dissociability that can cleave the bond between the acid dissociable group and the atom adjacent to the acid dissociable group by the action of an acid, or
(Ii) A group capable of cleaving a bond between the acid dissociable group and an atom adjacent to the acid dissociable group by further causing a decarboxylation reaction after partial bond cleavage is caused by the action of an acid. ,
Say both sides.
The acid dissociable group constituting the acid decomposable group is required to be a group having a polarity lower than that of the polar group generated by the dissociation of the acid dissociable group, whereby the acid dissociable group is formed by the action of an acid. When dissociates, a polar group having a polarity higher than that of the acid-dissociable group is generated to increase the polarity. As a result, the polarity of the entire component (A1) is increased. As the polarity increases, the solubility in the developer relatively changes, and when the developer is an organic developer, the solubility decreases.

The acid dissociable group is not particularly limited, and those which have been proposed as acid dissociable groups of base resins for chemically amplified resists can be used.
Among the above polar groups, as an acid dissociable group for protecting a carboxy group or a hydroxyl group, for example, an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter referred to as “acetal type acid dissociable Group) may be mentioned.

［式中、Ｒａ’^１、Ｒａ’^２は水素原子またはアルキル基、Ｒａ’^３は炭化水素基、Ｒａ’^３は、Ｒａ’^１、Ｒａ’^２のいずれかと結合して環を形成してもよい。］

[Wherein, Ra ′ ¹ and Ra ′ ² are a hydrogen atom or an alkyl group, Ra ′ ³ is a hydrocarbon group, and Ra ′ ³ is bonded to any of Ra ′ ¹ and Ra ′ ² to form a ring Good. ]

In the formula (a1-r-1), as the alkyl group of Ra ′ ¹ and Ra ′ ² , they are mentioned as the substituent which may be bonded to the carbon atom at the α-position in the explanation of the α-substituted acrylic acid ester. The same as the alkyl group can be mentioned, with preference given to methyl or ethyl, and most preferred is methyl.

The ra ^'3 hydrocarbon group is preferably an alkyl group having 1 to 20 carbon atoms, the alkyl group is more preferably 1 to 10 carbon atoms; preferably a linear or branched alkyl group, specifically, Methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, 1,1-dimethylethyl group, 1,1-diethylpropyl group And 2,2-dimethylpropyl and 2,2-dimethylbutyl groups.

When Ra ′ ³ is a cyclic hydrocarbon group, it may be aliphatic or aromatic, or may be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 8 carbon atoms, and specific examples include cyclopentane, cyclohexane, cyclooctane and the like. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one hydrogen atom from polycycloalkane is preferable, and as the polycycloalkane, one having 7 to 12 carbon atoms is preferable. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

When it becomes an aromatic hydrocarbon group, specifically, an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene or the like as the contained aromatic ring; carbon atoms constituting the aromatic hydrocarbon ring And aromatic heterocycles partially substituted with heteroatoms; and the like. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, as the aromatic hydrocarbon group, a group (aryl group) obtained by removing one hydrogen atom from the aromatic hydrocarbon ring; a group in which one hydrogen atom of the aryl group is substituted with an alkylene group (for example, And arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group, etc .; and the like. The carbon number of the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

When Ra ′ ³ combines with any of Ra ′ ¹ and Ra ′ ² to form a ring, the cyclic group is preferably a 4 to 7-membered ring, more preferably a 4 to 6-membered ring. Specific examples of the cyclic group include tetrahydropyranyl group, tetrahydrofuranyl group and the like.

  As an acid dissociative group which protects a carboxy group among the said polar groups, the acid dissociative group represented by the following general formula (a1-r-2) is mentioned, for example (following formula (a1-r-2) Among the acid dissociable groups represented by), those composed of alkyl groups are hereinafter sometimes referred to as "tertiary alkyl ester type acid dissociable groups" for convenience.

［式中、Ｒａ’^４〜Ｒａ’^６は炭化水素基であり、Ｒａ’^５、Ｒａ’^６は互いに結合して環を形成してもよい。］

[In the Formula, Ra ′ ^{4 to} Ra ′ ⁶ are a hydrocarbon group, and Ra ′ ⁵ and Ra ′ ⁶ may be bonded to each other to form a ring. ]

Examples of the hydrocarbon group Ra ^'4 ~Ra' ⁶ include the same as the Ra ^'3. Ra ^'4 is preferably an alkyl group having 1 to 5 carbon atoms. When Ra ′ ⁵ and Ra ′ ⁶ bond to each other to form a ring, groups represented by general formula (a1-r2-1) shown below can be mentioned.
On the other hand, when Ra ′ ^{4 to} Ra ′ ⁶ are not bonded to each other and are independent hydrocarbon groups, groups represented by general formula (a1-r2-2) shown below can be mentioned.

［式中、Ｒａ’^１０は炭素数１〜１０のアルキル基、Ｒａ’^１１はＲａ’^１０が結合した炭素原子と共に脂肪族環式基を形成する基、Ｒａ’^１２〜Ｒａ’^１４は、それぞれ独立に炭化水素基を示す。］

[Wherein, Ra ′ ¹⁰ is an alkyl group having 1 to ¹⁰ carbon atoms, Ra ′ ¹¹ is a group forming an aliphatic cyclic group with a carbon atom to which Ra ′ ¹⁰ is bonded, and Ra ′ ^{12 to} Ra ′ ¹⁴ are each It independently represents a hydrocarbon group. ]

In the formula (a1-r2-1), the alkyl group of the alkyl group having 1 to ¹⁰ carbon atoms with Ra ′ ¹⁰ is a linear or branched alkyl group of Ra ′ ³ in the formula (a1-r-1) The groups mentioned as are preferred. Wherein (a1-r2-1), Ra 'aliphatic cyclic ^{group 11} is configured, Ra in formula (a1-r-1)' group listed as a cyclic alkyl group of ³ is preferred.

Wherein (a1-r2-2), it is preferable that Ra is ^'12 and Ra' ¹⁴ each independently represents an alkyl group having 1 to 10 carbon atoms, the alkyl group, Ra in formula (a1-r-1) The group mentioned as the linear or branched alkyl group of ' ³ is more preferable, a C1-C5 linear alkyl group is more preferable, and a methyl group or an ethyl group is particularly preferable. .
In Formula (a1-r2-2), Ra ′ ¹³ is a linear, branched or cyclic alkyl group exemplified as the hydrocarbon group of Ra ′ ³ in Formula (a1-r-1) Is preferred. Among these, the groups mentioned as the cyclic alkyl group of Ra ′ ³ are more preferable.

  The specific example of said Formula (a1-r2-1) is given to the following. In the following formulas, "*" indicates a bond.

  Specific examples of the formula (a1-r2-2) will be given below.

  Moreover, as an acid dissociable group which protects a hydroxyl group among the said polar groups, the acid dissociable group represented by the following general formula (a1-r-3) (hereinafter, for convenience, “tertiary alkyloxycarbonyl acid” Sometimes referred to as "dissociable group".

［式中、Ｒａ’^７〜Ｒａ’^９はアルキル基を示す。］

Wherein, Ra ^'7 ~Ra' ⁹ is an alkyl group. ]

In Formula (a1-r-3), Ra ′ ^{7 to} Ra ′ ⁹ is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably 1 to 3.
Further, the total carbon number of each alkyl group is preferably 3 to 7, more preferably 3 to 5 and most preferably 3 to 4.

  The structural unit (a1) is a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and an acid whose polarity is increased by the action of an acid. Structural units containing degradable groups; Structural units in which at least a part of hydrogen atoms in the hydroxyl groups of structural units derived from hydroxystyrene or hydroxystyrene derivatives are protected by a substituent containing the acid decomposable group; vinylbenzoic acid or The structural unit etc. with which at least one copy of the hydrogen atom in -C (= O) -OH of the structural unit derived from a vinyl benzoic acid derivative was protected by the substituent containing the said acid-degradable group etc. are mentioned.

Among the above, as the structural unit (a1), a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent is preferable.
As the structural unit (a1), structural units represented by any one of the following general formulas (a1-1) to (a1-3) are preferable.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。Ｖａ^１はエーテル結合、ウレタン結合、又はアミド結合を有していてもよい２価の炭化水素基であり、ｎ_ａ１は０〜２であり、
Ｒａ^１は上記式（ａ１−ｒ−１）〜（ａ１−ｒ−２）で表される酸解離性基である。
Ｗａ^１はｎ_ａ２＋１価の炭化水素基であり、ｎ_ａ２は１〜３である。
Ｒａ^２は上記式（ａ１−ｒ−１）または（ａ１−ｒ−３）で表される酸解離性基である。
Ｗａ^２はｎ_ａ３＋１価の炭化水素基であり、ｎ_ａ３は１〜３であり、
Ｖａ^２はエーテル結合、ウレタン結合、又はアミド結合を有していてもよい２価の炭化水素基であり、
Ｒａ^３は上記式（ａ１−ｒ−１）〜（ａ１−ｒ−２）で表される酸解離性基である。］

Wherein R represents a hydrogen atom, an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group which may have an ether bond, a urethane bond or an amide bond, and n _a1 is 0 to 2;
Ra ¹ represents an acid dissociable group represented by the formula (a1-r-1) ~ (a1-r-2).
Wa ¹ is an n a ₂ + 1-valent hydrocarbon group, and n a ₂ is 1 to 3.
Ra ² is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-3).
Wa ² is an n _a3 + 1-valent hydrocarbon group, and n _a3 is 1 to 3,
Va ² is a divalent hydrocarbon group which may have an ether bond, a urethane bond or an amide bond,
Ra ³ is an acid dissociable group represented by the above formulas (a1-r-1) to (a1-r-2). ]

In the general formulas (a1-1) to (a1-3), the alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, Examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with a halogen atom. 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.
As R, a hydrogen atom, an alkyl group of 1 to 5 carbon atoms, or a fluorinated alkyl group of 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable in terms of industrial availability.
In the general formula (a1-1), the hydrocarbon group of Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group as a bivalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is usually preferably saturated.
More specifically, as the aliphatic hydrocarbon group, a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in the structure, and the like can be mentioned.
Further, Va ¹ includes ^{one in which the} divalent hydrocarbon group is bonded via an ether bond, a urethane bond or an amide bond.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.
As a linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH _2- ], an ethylene group [-(CH ₂ ) _2- ], a trimethylene group [ _{- (CH 2) 3 -]} , a tetramethylene group _{[- (CH 2) 4 -} ], a pentamethylene group _{[- (CH 2) 5 -} ] , and the like.
As the branched aliphatic hydrocarbon group, preferably a branched chain alkylene group, _{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 -, - C (CH 2 An alkylethylene group such as CH ₃ ) ₂ -CH _2- ; an alkyltrimethylene group such as -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH _2-, etc .; -CH (CH ₃ ) _{CH 2 CH 2 CH 2 -,} - CH 2 CH (CH 3) CH 2 CH 2 - And the like alkyl alkylene group such as an alkyl tetramethylene group of. As an alkyl group in an alkyl alkylene group, a C1-C5 linear alkyl group is preferable.

As an aliphatic hydrocarbon group which contains a ring in the said structure, alicyclic hydrocarbon group (The group which remove | eliminated two hydrogen atoms from the aliphatic hydrocarbon ring), and an alicyclic hydrocarbon group are linear or branched Examples thereof include a group bonded to the end of a linear aliphatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group intervenes in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same as described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclopentane, cyclohexane and the like. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a polycycloalkane is preferable, and as the polycycloalkane, one having 7 to 12 carbon atoms is preferable, and specifically, adamantane , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring.
The aromatic hydrocarbon group as a divalent hydrocarbon group in Va ¹ preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, and still more preferably 5 to 20 carbon atoms. 15 is particularly preferred, and 6 to 10 is most preferred. However, the carbon number does not include the carbon number in the substituent.
Specifically as an aromatic ring which an aromatic hydrocarbon group has, aromatic hydrocarbon rings, such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene etc; some carbon atoms which comprise the said aromatic hydrocarbon ring are hetero And aromatic hetero rings substituted by atoms; and the like. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specifically, as the aromatic hydrocarbon group, a group in which two hydrogen atoms are removed from the aromatic hydrocarbon ring (arylene group); a group in which one hydrogen atom is removed from the aromatic hydrocarbon ring (aryl group And arylalkyl such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group etc. And the like. Groups in which one hydrogen atom is further removed from the aryl group in the group) and the like. The carbon number of the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In the formula (a1-2), the n _a2 + 1-valent hydrocarbon group in Wa ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, which may be saturated or unsaturated, and is preferably saturated. As the aliphatic hydrocarbon group, a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a linear or branched aliphatic hydrocarbon group It includes a group formed by combining an aliphatic hydrocarbon group in the structure containing a ring, and specific examples thereof include the same groups as Va ¹ of the aforementioned formula (a1-1).
The n _a2 +1 valence is preferably 2 to 4 and more preferably 2 or 3.

In the formula (a1-3), the n _a3 +1 monovalent hydrocarbon group in Wa ² may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, which may be saturated or unsaturated, and is preferably saturated. As the aliphatic hydrocarbon group, a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a linear or branched aliphatic hydrocarbon group It includes a group formed by combining an aliphatic hydrocarbon group in the structure containing a ring, and specific examples thereof include the same groups as Va ¹ of the aforementioned formula (a1-1).
The n _a3 +1 valence is preferably 2 to 4 and more preferably 2 or 3.
In the formula (a1-3), Va ² can be mentioned the same groups as Va ¹ of the formula (a1-1).

  As the formula (a1-2), a structural unit represented by general formula (a1-2-01) shown below is particularly desirable.

In formula (a1-201), Ra ² is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-3). n _a2 is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. c is an integer of 0 to 3, preferably 0 or 1, and more preferably 1. R is as defined above.
Specific examples of the above formulas (a1-1) and (a1-2) are shown below. In each of the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

  The proportion of the structural unit (a1) in the component (A) is preferably 10 to 80 mol%, more preferably 10 to 75 mol%, with respect to all the structural units constituting the component (A), 10 to 60 mol% Is more preferred. By setting the lower limit value or more, lithography properties such as sensitivity, resolution and LWR are also improved. Further, by setting the upper limit value or less, it is possible to balance with other constituent units.

(Constituent unit (a2c))
The structural unit (a2c) is a structural unit containing a carbonate-containing cyclic group.
The carbonate-containing cyclic group of the structural unit (a2c) is effective in enhancing the adhesion of the resist film to the substrate when the component (A1) is used for forming the resist film.
When the structural unit (a1) contains a carbonate-containing cyclic group in the structure, the structural unit also corresponds to the structural unit (a2c), but such a structural unit is a structural unit (a1) It corresponds and does not correspond to the structural unit (a2c).

  The structural unit (a2c) is preferably a structural unit represented by general formula (a2-1).

In the structural unit (a2c), in the above formula (a2-1), Ra ²¹ is a carbonate-containing cyclic group.

The “carbonate-containing cyclic group” refers to a cyclic group containing a ring (carbonate ring) containing —O—C (−O) —O— in the ring skeleton thereof. The carbonate ring is counted as the first ring, and when it has only a carbonate ring, it is a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of its structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.
The carbonate ring-containing cyclic group as the cyclic hydrocarbon group in R ¹ is not particularly limited, and any group can be used. Specifically, groups represented by general formulas (ax3-r-1) to (ax3-r-3) shown below can be mentioned.

［式中、Ｒａ’^ｘ３１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；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りｐ’は０〜３の整数であり、ｑ’は０または１である。］

[ ^Wherein , each of Ra ' ^{x 31} independently represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR ", -OC (= O) R", a hydroxyalkyl group or a cyano group R ′ ′ is a hydrogen atom or an alkyl group; A ′ ′ is an oxygen atom or an alkylene group having 1 to 5 carbon atoms which may contain a sulfur atom, an oxygen atom or a sulfur atom, and p ′ is 0 to 3 It is an integer and q 'is 0 or 1. ]

In the general formulas (ax3-r-1) to (ax3-r-3), A ′ ′ is the same as A ′ ′ in the general formula (a2-r-1).
Alkyl group in ra ^'31, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR ", - OC (= O) R", The hydroxyalkyl group, each of the general formulas (a2-r-1) ~ ( a2-r-7) as in the same as those exemplified in the description of the Ra ^'21 of the like.

  The specific example of group represented by general formula (ax3-r-1)-(ax3-r-3) below is given.

The structural unit (a2c) of the component (A1) may be of one type or of two or more types.
When the component (A1) has a structural unit (a2c), the proportion of the structural unit (a2c) is preferably 1 to 80 mol% with respect to the total of all structural units constituting the component (A1), The content is more preferably 5 to 70 mol%, further preferably 10 to 65 mol%, and particularly preferably 10 to 60 mol%. By setting the content to the lower limit value or more, the effect of containing the structural unit (a2c) can be sufficiently obtained, and by setting the content to the upper limit value or less, balance with other structural units can be achieved. The lithography properties and pattern shape of the

(Constituent unit (a3))
The structural unit (a3) is a structural unit containing a polar group-containing aliphatic hydrocarbon group (with the exception of those corresponding to the structural units (a1), (a2) and (a2c) described above).
When the component (A1) has the structural unit (a3), the hydrophilicity of the component (A) is enhanced, which is considered to contribute to the improvement of the resolution.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom, with a hydroxyl group being particularly preferable.
As an aliphatic hydrocarbon group, a C1-C10 linear or branched hydrocarbon group (preferably alkylene group) and cyclic aliphatic hydrocarbon group (cyclic group) are mentioned. The cyclic group may be a monocyclic group or a polycyclic group. For example, in the resin for a resist composition for ArF excimer laser, it can be appropriately selected and used from those proposed in large numbers. The cyclic group is preferably a polycyclic group, and more preferably 7 to 30 carbon atoms.
Among them, a structural unit derived from an acrylic acid 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 preferred. Examples of the polycyclic group include groups in which two or more hydrogen atoms have been removed from a bicycloalkane, tricycloalkane, tetracycloalkane or the like. Specific examples thereof 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, groups in which two or more hydrogen atoms are removed from adamantane, groups in which two or more hydrogen atoms are removed from norbornane, and groups in which two or more hydrogen atoms are removed from tetracyclododecane are Industrially preferred.

The structural unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any structural unit can be used.
The structural unit (a3) is a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and contains a polar group-containing aliphatic hydrocarbon group Constituent units are preferred.
As the structural unit (a3), 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, it is derived from hydroxyethyl ester of acrylic acid Structural unit is preferable, and when the hydrocarbon group is a polycyclic group, a structural unit represented by the following formula (a3-1), a structural unit represented by the formula (a3-2), a formula ( The structural unit represented by a3-3) is mentioned as a preferable thing.

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

[Wherein, R is as defined above, j is an integer of 1 to 3, k is an integer of 1 to 3, t 'is an integer of 1 to 3, and l is an integer of 1 to 5] And s is an integer of 1 to 3. ]

In the formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group be bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group be bonded to the 3rd position of the adamantyl group.
j is preferably 1, and particularly preferably, the hydroxyl group is bonded to the 3-position of the adamantyl group.

In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5- or 6-position of the norbornyl group.
In formula (a3-3), t ′ is preferably 1. l is preferably 1. s is preferably 1. As for these, it is preferable that 2- norbornyl group or 3- norbornyl group is couple | bonded with the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

The structural unit (a3) contained in the component (A1) may be of one type or of two or more types.
The proportion of the structural unit (a3) in the component (A1) is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, based on the total of all structural units constituting the resin component (A1). Preferably, 5 to 35 mol% is more preferable.
By setting the ratio of the structural unit (a3) to the lower limit value or more, an effect by containing the structural unit (a3) is sufficiently obtained, and by setting the ratio to the upper limit value or less, balance with other structural units is balanced. It will be easier.

(Constituent unit (a4))
The structural unit (a4) is a structural unit containing a non-acid dissociable cyclic group. When the component (A1) has the structural unit (a4), the dry etching resistance of the formed resist pattern is improved. In addition, the hydrophobicity of the component (A1) is enhanced. The improvement of the hydrophobicity is considered to contribute to the improvement of the resolution, the resist pattern shape and the like particularly in the case of organic solvent development.
The “non-acid-dissociable cyclic group” in the structural unit (a4) is a ring remaining in the structural unit as it is without dissociation even if the acid acts when the acid is generated from the component (B) upon exposure. It is a formula group.
As the structural unit (a4), for example, a structural unit derived from an acrylic acid ester containing a non-acid dissociable aliphatic cyclic group is preferable. The cyclic group may be, for example, the same one as exemplified in the case of the structural unit (a1), and for an ArF excimer laser, for a KrF excimer laser (preferably for an ArF excimer laser), etc. A large number of materials conventionally known as those used for the resin component of the resist composition of the present invention can be used.
Particularly, at least one selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group is preferable from the viewpoint of industrial availability and the like. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.
Specifically as a structural unit (a4), the thing of the structure of the following general formula (a4-1)-(a4-7) can be illustrated.

［式中、Ｒ^αは、水素原子、メチル基またはトリフルオロメチル基を示す。］

[Wherein, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group. ]

The structural unit (a4) contained in the component (A1) may be of one type or of two or more types.
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 structural units constituting the component (A1), It is more preferable that it is 10-20 mol%.

(Constituent unit (a9))
As the structural unit (a9), structural units represented by general formula (a9-1) shown below are preferable.

［式中、Ｒは前記と同様であり、Ｙａ^９１は単結合または２価の連結基であり、Ｒ^９１は置換基を有していてもよい炭化水素基であり、Ｒ^９２は酸素原子または硫黄原子である。］

Wherein R is as defined above, Ya ⁹¹ is a single bond or a divalent linking group, R ⁹¹ is a hydrocarbon group which may have a substituent, and R ⁹² is an oxygen atom It is a sulfur atom. ]

Examples of the divalent linking group for Ya ⁹¹ in the formula (a9-1) include the same groups as the divalent linking group for Ya ²¹ in the formula (a2-1). Ya ⁹¹ is preferably a single bond.

In the formula (a9-1), as a hydrocarbon group for R ⁹¹ , an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, an aralkyl group and the like can be mentioned.
The alkyl group in R ⁹¹ preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and may be linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group etc. are mentioned as a preferable thing.
The monovalent alicyclic hydrocarbon group for R ⁹¹ preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms, and may be polycyclic or monocyclic. As a monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples include cyclobutane, cyclopentane, cyclohexane and the like. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from polycycloalkane is preferable, and as the polycycloalkane, one having 7 to 12 carbon atoms is preferable, and specifically, Examples include adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.
The aryl group for R ⁹¹ preferably has 6 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, and particularly preferably a phenyl group.
Aralkyl groups for R ⁹¹ include those in which the "aryl group for R ^91" alkylene group and the above C1-8 bonded are preferred examples. More preferably an aralkyl group and is bonded "aryl group for R ^91" alkylene group and the 1 to 6 carbon atoms, an aralkyl group in which the "aryl group for R ^91" alkylene group and the 1 to 4 carbon atoms bonded Is particularly preferred.
In the hydrocarbon group for R ⁹¹ , part or all of the hydrogen atoms of the hydrocarbon group are preferably substituted with fluorine atoms, and 30 to 100% of the hydrogen atoms of the hydrocarbon groups are substituted with fluorine atoms Is more preferable. Among them, particularly preferred is a perfluoroalkyl group in which all of the hydrogen atoms of the above-mentioned alkyl group are substituted with a fluorine atom.

The hydrocarbon group in R ⁹¹ may have a substituent. Examples of the substituent include a halogen atom, an oxo group (= O), a hydroxyl group (—OH), an amino group (—NH ₂ ), and —SO ₂ —NH ₂ . In addition, a part of carbon atoms constituting the hydrocarbon group may be substituted with a substituent containing a hetero atom. As a substituent containing the hetero atom, -O-, -NH-, -N =, -C (= O) -O-, -S-, -S (= O) _2- , -S (= O ₂ ) -O- is mentioned.
In R ⁹¹ , as a hydrocarbon group having a substituent, a lactone-containing cyclic group represented by General Formulas (a2-r-1) to (a2-r-7) described above, and a general formula (a5 to be described later) -r-1) ~ (a5- r-4) with -SO ₂ represented respectively - containing cyclic group; represented by the following chemical formula, a substituted aryl group, such as a monovalent heterocyclic group.

The specific example of the structural unit represented by said Formula (a9-1) is shown below. In the following formulae, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

In the present invention, the structural unit (a9) contained in the component (A1) may be one type or two or more types.
When the component (A1) has the structural unit (a9), the proportion of the structural unit (a9) is preferably 1 to 40 mol% with respect to the total of all structural units constituting the component (A1) 5-30 mol% is more preferable. By setting the ratio of the structural unit (a9) to the lower limit value or more, the lithography properties such as the development characteristics and the EL margin are improved, and by setting the ratio to the upper limit value or less, balance with other structural units becomes easy.

  In the present invention, the component (A1) is a copolymer having the structural units (a0), (a2) and (a3), a copolymer having the structural units (a0) and (a2), and the structural units (a0) and (a2) The copolymer having a2) and (a1) and the copolymer having the structural units (a0), (a2) and (a9) are more preferable.

In the present invention, the weight average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography) of the component (A1) is not particularly limited, and 1000 to 50000 is preferable, 1500 to 30000 is more preferable, and 2000 -20000 is most preferred. When it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and when it is above the lower limit of this range, the dry etching resistance and the resist pattern cross-sectional shape are good.
The degree of dispersion (Mw / Mn) of the component (A1) is not particularly limited, and is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and 1.2 to 2 .5 is most preferred. In addition, Mn shows a number average molecular weight.

As the component (A1), one type may be used alone, or two or more types may be used in combination.
25 mass% or more is preferable with respect to the total mass of a base material component (A), as for the ratio of the (A1) component in a base material component (A), 50 mass% is more preferable, 75 mass% is more preferable, and 100 It may be mass%. When the proportion is 25% by mass or more, lithography properties such as MEF, circularity, and roughness reduction are further improved.

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

«Acid Generator Component»
The resist composition of the present invention comprises an acid generator component (B) (hereinafter referred to as component (B)) that generates an acid upon exposure to light, containing a compound represented by the following general formula (b-1) or (b-2) Containing).

［式（ｂ−１）及び（ｂ−２）中、Ｒ^１０１は置換基を有していてもよい環式基である。Ｒ^１０４、Ｒ^１０５は、それぞれ独立に置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基であり、相互に結合して環を形成していてもよい。Ｒ^１０４、Ｒ^１０５の少なくとも一方は置換基を有していてもよい環式基である。Ｒ^１０２はフッ素原子または炭素数１〜５のフッ素化アルキル基である。Ｙ^１０１は単結合または酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３はそれぞれ独立に単結合、アルキレン基、またはフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２はそれぞれ独立に単結合または酸素原子である。ｍは１以上の整数であって、Ｍ’^ｍ＋はｍ価の有機カチオンである。］

[In Formula (b-1) and (b-2), R ¹⁰¹ is a cyclic group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ each independently represent a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain which may have a substituent And the alkenyl group may be bonded to each other to form a ring. At least one of R ¹⁰⁴ and R ¹⁰⁵ is a cyclic group which may have a substituent. R ¹⁰² is a fluorine atom or a fluorinated alkyl group of 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ^{101 to} V ¹⁰³ each independently represent a single bond, an alkylene group, or a fluorinated alkylene group. L ^{101 to} L ¹⁰² each independently represent a single bond or an oxygen atom. m is an integer of 1 or more, and M ' ^{m +} is an m-valent organic cation. ]

  The acid generator containing the compound represented by the general formula (b-1) or (b-2), contained in the resist composition of the present invention, which generates an acid upon exposure to light, has a short diffusion length of the generated acid. Therefore, the lithography characteristics can be made favorable.

{Anion part}
Anion Part of Component (b-1) In Formula (b-1), R ¹⁰¹ is a cyclic group which may have a substituent.

(Cyclic group which may have a substituent)
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group.
The aromatic hydrocarbon group for R ¹⁰¹ is selected from the aromatic hydrocarbon ring mentioned for the divalent aromatic hydrocarbon group for Va ¹ in the formula (a1-1), or an aromatic compound containing two or more aromatic rings The aryl group which removed one hydrogen atom is mentioned, A phenyl group and a naphthyl group are preferable.
The cyclic aliphatic hydrocarbon group for R ¹⁰¹ is a group obtained by removing one hydrogen atom from the monocycloalkane or polycycloalkane listed as the divalent aliphatic hydrocarbon group for Va ¹ in the formula (a1-1). And an adamantyl group and a norbornyl group are preferable.
In addition, the cyclic hydrocarbon group in R ¹⁰¹ may contain a hetero atom such as a heterocyclic ring, and more specifically, each of them is represented by the general formulas (a2-r-1) to (a2-r-7). Lactone-containing cyclic groups, -SO ₂ -containing cyclic groups represented by the above general formulas (a5-r-1) to (a5-r-4), and heterocyclic groups listed below. Be

Examples of the substituent in the cyclic hydrocarbon group of R ¹⁰¹ include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group and the like.
The alkyl group as a substituent 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.
As an alkoxy group as a substituent, a C1-C5 alkoxy group is preferable, and a methoxy group, an ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group is more preferable, and methoxy is preferable. And ethoxy groups are most preferred.
As a halogen atom as a substituent, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned, A fluorine atom is preferable.
As a halogenated alkyl group as a substituent, a part or all of hydrogen atoms, such as an alkyl group having 1 to 5 carbon atoms, such as methyl group, ethyl group, propyl group, n-butyl group, tert-butyl group, etc. The group substituted by the halogen atom is mentioned.

Among them, more specifically, R ¹⁰¹ is a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from polycycloalkane, and the above-mentioned formulas (a2-r-1) to (a2-r-7). lactone-containing cyclic group represented respectively), -SO ₂ respectively represented by the general formula (a5-r-1) ~ (a5-r-4) - such as containing cyclic group.

In formula (b-1), Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom.
When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, the Y ¹⁰¹ may contain an atom other than the oxygen atom. As an atom other than an oxygen atom, a carbon atom, a hydrogen atom, a sulfur atom, a nitrogen atom etc. are mentioned, for example.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: -O-), an ester bond (-C (= O) -O-), an oxycarbonyl group (-O-C (= O Non-hydrocarbons such as)-), amide bond (-C (= O) -NH-), carbonyl group (-C (= O)-), carbonate bond (-O-C (= O) -O-) etc And oxygen atom-containing linking groups of the system; combinations of such non-hydrocarbon oxygen atom-containing linking groups and alkylene groups, and the like. A sulfonyl group (—SO ₂ —) may be further linked to the combination. As the said combination, the coupling group respectively represented by following formula (y-al-1)-(y-al-7) is mentioned, for example.

［式中、Ｖ’^１０１は単結合または炭素数１〜５のアルキレン基であり、Ｖ’^１０２は炭素数１〜３０の２価の飽和炭化水素基である。］

[In Formula, V ' ¹⁰¹ is a single bond or a C1-C5 alkylene group, V' ¹⁰² is a C1-C30 bivalent saturated hydrocarbon group. ]

The divalent saturated hydrocarbon group in V ′ ¹⁰² is preferably an alkylene group having 1 to 30 carbon atoms.

The alkylene group in V ′ ¹⁰¹ and V ′ ¹⁰² may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferable.
Specific examples of the alkylene group as V ′ ¹⁰¹ and V ′ ¹⁰² include methylene group [—CH ₂ —]; —CH (CH ₃ ) —, —CH (CH ₂ CH ₃ ) —, and —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 ) alkyl ethylene group such as 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 - and the like alkyl trimethylene group; tetramethylene _{[-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; pentamethylene group _{[-CH 2 CH 2 CH 2 CH} 2 CH 2 -] , and the like.
Moreover, a part of methylene group in the said alkylene group in V ' ¹⁰¹ or V' ¹⁰² may be substituted by the C5-C10 bivalent aliphatic cyclic group. The aliphatic cyclic group is preferably a divalent group in which one hydrogen atom is further removed from the cyclic aliphatic hydrocarbon group of Ra ′ ^{3 in} the formula (a1-r-1), and a cyclohexylene group 1,5-adamantylene group or 2,6-adamantylene group is more preferable.

As Y ¹⁰¹ , a divalent linking group containing an ester bond or an ether bond is preferable, and a linking group represented by the above-mentioned formulas (y-al-1) to (y-al-5) is preferable.

In formula (b-1), V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group in V ¹⁰¹ and the fluorinated alkylene group preferably have 1 to 4 carbon atoms. ^Examples of the fluorinated alkylene group in V ¹⁰¹ include groups in which part or all of hydrogen atoms of the alkylene group in V ¹⁰¹ are substituted with a fluorine atom. Among them, V ¹⁰¹ is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

In formula (b-1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰² is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

As a specific example of the anion part of (b-1) component, when Y ¹⁰¹ is a divalent linking group containing an oxygen atom, for example, any of the following formulas (an-1) to (an-3) The anion represented is mentioned.

［式中、Ｒ”^１０１は、置換基を有していてもよい脂肪族環式基、前記式（ｒ−ｈｒ−１）〜（ｒ−ｈｒ−６）でそれぞれ表される基、；Ｒ”^１０２は、置換基を有していてもよい脂肪族環式基、前記式（ａ２−ｒ−１）〜（ａ２−ｒ−７）でそれぞれ表されるラクトン含有環式基、又は前記一般式（ａ５−ｒ−１）〜（ａ５−ｒ−４）でそれぞれ表される−ＳＯ_２−含有環式基であり；Ｒ”^１０３は、置換基を有していてもよい芳香族環式基、置換基を有していてもよい脂肪族環式基、であり；Ｖ”^１０１は、フッ素化アルキレン基であり；Ｌ”^１０１は、−Ｃ（＝Ｏ）−又は−ＳＯ_２−であり；ｖ”はそれぞれ独立に０〜３の整数であり、ｑ”はそれぞれ独立に１〜２０の整数であり、ｎ”は０または１である。］

[Wherein, R ′ ′ ¹⁰¹ is an aliphatic cyclic group which may have a substituent, a group represented by each of the above formulas (r-hr-1) to (r-hr-6), “ ¹⁰² is an aliphatic cyclic group which may have a substituent, a lactone-containing cyclic group respectively represented by the formulas (a2-r-1) to (a2-r-7), or the general group -SO ₂ -containing cyclic group represented by each of formulas (a5-r-1) to (a5-r-4); and R ′ ′ ¹⁰³ is an aromatic cyclic group which may have a substituent Group, an optionally substituted aliphatic cyclic group; V ′ ′ ¹⁰¹ is a fluorinated alkylene group; L ′ ′ ¹⁰¹ is —C (= O) — or —SO ₂ — V ′ ′ is each independently an integer of 0 to 3, q ′ ′ is each independently an integer of 1 to 20, and n ′ ′ is 0 or 1. ]

The aliphatic cyclic group which may have a substituent of R ′ ′ ¹⁰¹ , R ′ ′ ¹⁰² and R ′ ′ ¹⁰³ is preferably the group exemplified as the cyclic aliphatic hydrocarbon group for R ¹⁰¹ above. Examples of the substituent include those similar to the substituents which may substitute the cyclic aliphatic hydrocarbon group for R ¹⁰¹ .

The aromatic cyclic group which may have a substituent in R ′ ¹⁰³ is preferably the group exemplified as the aromatic hydrocarbon group in the cyclic hydrocarbon group in R ¹⁰¹ described above. And the same as the substituent which may substitute the aromatic hydrocarbon group in R ¹⁰¹ .

  Specific examples of the anion moiety represented by the above formula (an-1) are shown below.

  Specific examples of the anion moiety represented by the above formula (an-2) are shown below.

  Specific examples of the anion moiety represented by the above formula (an-3) are shown below.

-Anion part of component (b-2) In formula (b-2), each of R ¹⁰⁴ and R ¹⁰⁵ may independently have a cyclic group substituent which may have a substituent. A cyclic alkyl group or a linear alkenyl group which may have a substituent, and for the cyclic group which may have a substituent, R ¹⁰¹ in the formula (b-1) The same as those mentioned above. The chain-like alkyl group which may have a substituent or the chain-like alkenyl group which may have a substituent is the same as those mentioned for R ′ ²⁰¹ described later. However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring. When R ¹⁰⁴ and R ¹⁰⁵ are not bonded to each other, at least one of them is a cyclic group which may have a substituent.
In formula (b-2), each of V ¹⁰² and V ¹⁰³ independently represents a single bond, an alkylene group, or a fluorinated alkylene group, and each of them is the same as V ¹⁰¹ in formula (b-1) It can be mentioned.
In formula (b-2), L ^{101 to} L ¹⁰² each independently represent a single bond or an oxygen atom.
Specific examples of the anion moiety represented by the above formula (b-2) are shown below.

{Cation part}
In the formulas (b-1) and (b-2), M ' ^{m +} is an m-valent organic cation other than the cation in the compound of the formula (b1-1), and more preferably a sulfonium cation or an iodonium cation The cation represented by each of the following general formulas (ca-1) to (ca-4) is particularly preferable.

［式中、Ｒ^２０１〜Ｒ^２０７、およびＲ^２１１〜Ｒ^２１２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、アルキル基またはアルケニル基を表し、Ｒ^２０１〜Ｒ^２０３、Ｒ^２０６〜Ｒ^２０７、Ｒ^２１１〜Ｒ^２１２は、相互に結合して式中のイオウ原子と共に環を形成してもよい。Ｒ^２０８〜Ｒ^２０９はそれぞれ独立に水素原子または炭素数１〜５のアルキル基を表し、Ｒ^２１０は置換基を有していてもよいアリール基、アルキル基、アルケニル基、又は−ＳＯ_２−含有環式基であり、Ｌ^２０１は−Ｃ（＝Ｏ）−または−Ｃ（＝Ｏ）−Ｏ−を表し、Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基またはアルケニレン基を表し、ｘは１または２であり、Ｗ^２０１は（ｘ＋１）価の連結基を表す。］

[Wherein, R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² each independently represent an aryl group which may have a substituent, an alkyl group or an alkenyl group, and R ^{201 to} R ²⁰³ and R ²⁰⁶ to R ²⁰⁷ and R ^{211 to} R ²¹² may be mutually bonded to form a ring with the sulfur atom in the formula. R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon ^{atoms, R 210} is an optionally substituted aryl group, an alkyl group, an alkenyl group, or -SO ₂ - containing L ²⁰¹ represents a cyclic group, L ²⁰¹ represents —C (= O) — or —C (、 O) —O—, Y ²⁰¹ represents each independently an arylene group, an alkylene group or an alkenylene group, and x represents And W ²⁰¹ represents a (x + 1) -valent linking group. ]

As the aryl group in R ²⁰¹ to R ^207, and ^R 211 ^{to R 212,} include unsubstituted aryl group having 6 to 20 carbon atoms, a phenyl group, a naphthyl group.
The alkyl group of R ²⁰¹ to R ^207, and ^R 211 ^{to R 212,} a chain or cyclic alkyl group, preferably from 1 to 30 carbon atoms.
The alkenyl group in R ²⁰¹ to R ^207, and ^R 211 ^{to R 212,} preferably has 2 to 10 carbon atoms.
Examples of the substituent which R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group and an arylthio group. And groups represented by the following formulas (ca-r-1) to (ca-r-7) can be given.
The aryl group in the arylthio group as a substituent is the same as that described for R ¹⁰¹ , and specific examples thereof include a phenylthio group or a biphenylthio group.

［式中、Ｒ’^２０１はそれぞれ独立に、水素原子、置換基を有していてもよい環式基、鎖状のアルキル基、または鎖状のアルケニル基である。］

[Wherein, R ′ ²⁰¹ each independently represents a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group, or a chain alkenyl group. ]

R ′ ^{201 is} a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. Examples of the cyclic group which may have a substituent of R ′ ²⁰¹ include the same ones as R ¹⁰¹ in the above formula (b-1).

(Chain-like alkyl group which may have a substituent)
The linear alkyl group of R ′ ²⁰¹ may be linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, decanyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl Groups, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group and the like.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methyl pentyl group, 2-methyl pentyl group, 3-methyl pentyl group, 4-methyl pentyl group etc. are mentioned.

(Acyclic alkenyl group which may have a substituent)
The chained alkenyl group of R ′ ²⁰¹ may be linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, and still more preferably 2 to 4 carbon atoms. 3 is particularly preferred. As a linear alkenyl group, a vinyl group, propenyl group (allyl group), butynyl group etc. are mentioned, for example. As a branched alkenyl group, 1-methyl propenyl group, 2-methyl propenyl group etc. are mentioned, for example.
Among the above, a propenyl group is particularly preferable as the chained alkenyl group.

As a substituent in the chain alkyl group or alkenyl group of R ′ ²⁰¹ , for example, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, a cyclic group in the above R ^{101 and} the like Can be mentioned.

The chain alkyl group of R ′ ²⁰¹ or the substituent which the chain alkenyl group may have is the same as the substituent which R ¹⁰¹ may have.
In addition, the same acid dissociable group represented by the above formula (a1-r-2) as a cyclic group which may have a substituent or a chain-like alkyl group which may have a substituent The thing is also mentioned.

When R ^{201 to} R ²⁰³ , R ^{206 to} R ²⁰⁷ and R ^{211 to} R ²¹² are mutually bonded to form a ring with the sulfur atom in the formula, a hetero atom such as a sulfur atom, an oxygen atom or a nitrogen atom, carbonyl _{group, -SO -, - SO 2 -} , - SO 3 -, - COO -, - CONH- , or -N _(R N) - (. the _{R N} is an alkyl group having 1 to 5 carbon atoms), etc. May be bonded via a functional group of As the ring to be formed, one ring containing a sulfur atom in the formula in its ring skeleton is preferably a 3- to 10-membered ring, including a sulfur atom, and particularly preferably a 5- to 7-membered ring preferable. Specific examples of the ring formed include, for example, thiophene ring, thiazole ring, benzothiophene ring, thianthrene ring, benzothiophene ring, dibenzothiophene ring, 9H-thioxanthene ring, thioxanthone ring, thianthrene ring, phenoxathiin ring, tetrahydrofuran Thiophenium rings, tetrahydrothiopyranium rings and the like can be mentioned.

R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms are preferred, and combined if mutually serving as alkyl ring May be formed.

R ²¹⁰ may have an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent -SO ₂ - containing cyclic group.
As an aryl group in R ^210, a C6-C20 unsubstituted aryl group is mentioned, A phenyl group and a naphthyl group are preferable.
The alkyl group in R ²¹⁰ is preferably a linear or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group in R ²¹⁰ preferably has 2 to 10 carbon atoms.
The —SO ₂ — containing cyclic group which may have a substituent in R ²¹⁰ is the same as the “—SO ₂ -containing cyclic group” of Ra ^{21 in} the general formula (a2-1) above And the group represented by the above general formula (a5-r-1) is preferable.

Each Y ²⁰¹ independently represents an arylene group, an alkylene group or an alkenylene group.
The arylene group in Y ²⁰¹ is a group in which one hydrogen atom has been removed from the aryl group exemplified as the aromatic hydrocarbon group in R ¹⁰¹ in the above formula (b-1).
Examples of the alkylene group and the alkenylene group in Y ²⁰¹ include the same as the aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ in the general formula (a1-1).

In the formula (ca-4), x is 1 or 2.
W ²⁰¹ is a (x + 1) valent, ie, a divalent or trivalent linking group.
Examples of the divalent linking group for W ^201, a divalent hydrocarbon group which may have a substituent is preferably a hydrocarbon group similar to Ya ²¹ in the general formula (a2-1) can be exemplified. The divalent linking group in W ²⁰¹ may be linear, branched or cyclic, and is preferably cyclic. Among them, a group in which two carbonyl groups are combined at both ends of an arylene group is preferable. As an arylene group, a phenylene group, a naphthylene group, etc. are mentioned, A phenylene group is especially preferable.
^Examples of the trivalent linking group in W ²⁰¹ include a group obtained by removing one hydrogen atom from the divalent linking group in W ²⁰¹ , a group in which the divalent linking group is further bonded to the divalent linking group, and the like. It can be mentioned. The trivalent linking group in W ²⁰¹ is preferably a group in which two carbonyl groups are bonded to an arylene group.

  Specific examples of suitable cations represented by Formula (ca-1) include cations represented by the following Formulas (ca-1-1) to (ca-1-63).

［式中、ｇ１、ｇ２、ｇ３は繰返し数を示し、ｇ１は１〜５の整数であり、ｇ２は０〜２０の整数であり、ｇ３は０〜２０の整数である。］

[In formula, g1, g2, g3 shows repetition number, g1 is an integer of 1-5, g2 is an integer of 0-20, g3 is an integer of 0-20. ]

［式中、Ｒ”^２０１は水素原子又は置換基であって、置換基としては前記Ｒ^２０１〜Ｒ^２０７、およびＲ^２１０〜Ｒ^２１２が有していてもよい置換基として挙げたものと同様である。］

[Wherein, R ′ ′ ²⁰¹ is a hydrogen atom or a substituent, and as the substituent, it is the same as those mentioned as the substituents that R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have. is there.]

  Specifically as a suitable cation represented by said Formula (ca-3), the cation respectively represented by following formula (ca-3-1)-(ca-3-6) is mentioned.

  Specifically as a suitable cation represented by said Formula (ca-4), the cation respectively represented by following formula (ca-4-1)-(ca-4-2) is mentioned.

As the component (B), one type of acid generator described above may be used alone, or two or more types may be used in combination.
When the resist composition of the present invention contains the component (B), the content of the component (B) is preferably 0.5 to 60 parts by mass, and 1 to 50 parts by mass with respect to 100 parts by mass of the component (A). Is more preferable, and 1 to 40 parts by mass is further preferable. By setting the content of the component (B) in the above range, pattern formation is sufficiently performed. In addition, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is obtained, and storage stability is preferably improved.

<Basic compound component; (D) component>
In the resist composition of the present invention, in addition to the component (A) or to the components (A) and (B), an acid diffusion controller component (hereinafter also referred to as "component (D)") is further added. You may contain.
The component (D) acts as a quencher (acid diffusion control agent) which traps an acid generated by the exposure from the component (B) and the like.
The component (D) in the present invention may be a photodisintegrable base (D1) (hereinafter referred to as "component (D1)") which is decomposed by exposure to lose acid diffusion controllability, and the component (D1) may be used. It may be a nitrogen-containing organic compound (D2) (hereinafter referred to as “component (D2)”) which does not correspond.

[(D1) component]
By using the resist composition containing the component (D1), it is possible to improve the contrast between the exposed area and the non-exposed area when forming a resist pattern.
The component (D1) is not particularly limited as long as it decomposes by exposure and loses acid diffusion controllability, and a compound represented by the following general formula (d1-1) (hereinafter "component (d1-1)") A compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component") and a compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1- 3) One or more types of compounds selected from the group consisting of components.
The components (d1-1) to (d1-3) do not act as a quencher because they decompose in the exposed area and lose acid diffusion controllability (basicity), and act as a quencher in the unexposed area.

［式中、Ｒｄ^１〜Ｒｄ^４は置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基である。ただし、式（ｄ１−２）中のＲｄ^２における、Ｓ原子に隣接する炭素原子にはフッ素原子は結合していないものとする。Ｙｄ^１は単結合、または２価の連結基である。Ｍ^ｍ＋はそれぞれ独立にｍ価の有機カチオンである。］

[Wherein, Rd ^{1 to} Rd ⁴ each represents a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain which may have a substituent] Alkenyl group of However, it is assumed that a fluorine atom is not bonded to the carbon atom adjacent to the S atom in Rd ² in the formula (d1-2). Yd ¹ is a single bond or a divalent linking group. M ^{m +} is each independently an m-valent organic cation. ]

{(D1-1) ingredients}
Anion part In the formula (d1-1), Rd ¹ has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent It is also a chain-like alkenyl group, and the same as R ¹⁰¹ can be mentioned.
Among these, Rd ¹ may have an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent. Chain hydrocarbon groups are preferred. As a substituent which these groups may have, a hydroxyl group, a fluorine atom or a fluorinated alkyl group is preferable.
The aromatic hydrocarbon group is more preferably a phenyl group or a naphthyl group.
The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane.
As the chain hydrocarbon group, a chain alkyl group is preferable. The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically includes methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl and nonyl groups. Groups, linear alkyl groups such as decyl group; 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group And branched alkyl groups such as 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.

When the chained alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the carbon number of the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and 1 The fluorinated alkyl group of which -4 is more preferably may contain an atom other than a fluorine atom. As an atom other than a fluorine atom, an oxygen atom, a carbon atom, a hydrogen atom, a sulfur atom, a nitrogen atom etc. are mentioned, for example.
Rd ¹ is preferably a fluorinated alkyl group in which a part or all of the hydrogen atoms constituting the linear alkyl group are substituted by a fluorine atom, and one of the hydrogen atoms constituting the linear alkyl group is preferred. It is preferable that they are all fluorinated alkyl groups (linear perfluoroalkyl groups) substituted with a fluorine atom.

  The preferable specific example of the anion part of a (d1-1) component is shown below.

-Cation part In formula (d1-1), Mm ⁺ is a m-valent organic cation.
The organic cation of M ^{m +} is not particularly limited, and examples thereof include the same ones as the cations represented by the general formulas (ca-1) to (ca-4), respectively, and The cation represented by 1) to (ca-1-63) is preferable.
As the component (d1-1), one type may be used alone, or two or more types may be used in combination.

{(D1-2) ingredients}
Anion Part In the formula (d1-2), Rd ² has a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a substituent. It may be a chain-like alkenyl group, and examples thereof include the same as R ¹⁰¹ .
However, a fluorine atom is not bonded to the carbon atom adjacent to the S atom in Rd ² (not substituted with fluorine). As a result, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the quenching ability of the component (D) is improved.
Rd ² is preferably an aliphatic cyclic group which may have a substituent, and is a group in which one or more hydrogen atoms have been removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane or the like It is more preferable that it is a group obtained by removing one or more hydrogen atoms from camphor or the like.
The hydrocarbon group of Rd ² may have a substituent, and as the substituent, a hydrocarbon group (aromatic hydrocarbon group, aliphatic hydrocarbon group) in Rd ¹ of the above formula (d1-1) can be mentioned The same as the substituent which may have is mentioned.

  The preferable specific example of the anion part of (d1-2) component is shown below.

-Cation part In Formula (d1-2), Mm ⁺ is a m-valent organic cation, and is the same as Mm ⁺ in said Formula (d1-1).
As the component (d1-2), one type may be used alone, or two or more types may be used in combination.

{(D1-3) ingredients}
Anion part In the formula (d1-3), Rd ³ has a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a substituent It is also a chain-like alkenyl group, and the same as R ¹⁰¹ can be mentioned, and a cyclic group containing a fluorine atom, a chain-like alkyl group, or a chain-like alkenyl group is preferable. Among them, a fluorinated alkyl group is preferable, and the same fluorinated alkyl group as Rd ¹ is more preferable.

In formula (d1-3), Rd ⁴ may have a cyclic group which may have a substituent, a chained alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group, and the same as R ¹⁰¹ can be mentioned.
Among them, an alkyl group which may have a substituent, an alkoxy group, an alkenyl group and a cyclic group are preferable.
The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group And tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. A part of the hydrogen atoms of the alkyl group of Rd ⁴ may be substituted with a hydroxyl group, a cyano group or the like.
The alkoxy group in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and as the alkoxy group having 1 to 5 carbon atoms, specifically, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, n- Examples include butoxy and tert-butoxy. Among these, methoxy and ethoxy are preferable.

The alkenyl group in Rd ⁴ includes the same ones as the above-mentioned R ^101, and a vinyl group, propenyl group (allyl group), 1-methylpropenyl group and 2-methylpropenyl group are preferable. These groups may further have an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms as a substituent.

Examples of the cyclic group for Rd ⁴ include the same as the above R ^101, and one or more hydrogen atoms are removed from cycloalkanes such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. Preferred is an alicyclic group, or an aromatic group such as a phenyl group or a naphthyl group. When Rd ⁴ is an alicyclic group, the resist composition is well dissolved in the organic solvent, whereby the lithography properties are improved. In addition, when Rd ⁴ is an aromatic group, in lithography using EUV or the like as an exposure light source, the resist composition is excellent in light absorption efficiency, and sensitivity and lithography characteristics become good.

In formula (d1-3), Yd ¹ is a single bond or a divalent linking group.
The divalent linking group in Y d ¹ is not particularly limited, and may be a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, a hetero atom And the like. Each of which include the same ones as exemplified in the description of the divalent linking group for Ya ²¹ in the formula (a2-1).
As Yd ¹ , a carbonyl group, an ester bond, an amide bond, an alkylene group or a combination thereof is preferable. The alkylene group is more preferably a linear or branched alkylene group, and still more preferably a methylene group or an ethylene group.

  The preferable specific example of the anion part of (d1-3) component is shown below.

-Cation part In Formula (d1-3), Mm ⁺ is a m-valent organic cation, and is the same as Mm ⁺ in said Formula (d1-1).
As the component (d1-3), one type may be used alone, or two or more types may be used in combination.

As the component (D1), any one of the components (d1-1) to (d1-3) may be used alone, or two or more thereof may be used in combination.
The content of the component (D1) is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, with respect to 100 parts by mass of the component (A), and 1 to 8 More preferably, it is part by weight.
When the content of the component (D1) is equal to or more than the preferable lower limit value, particularly favorable lithography characteristics and a resist pattern shape can be obtained. On the other hand, when it is below the upper limit value, the sensitivity can be favorably maintained and the throughput is also excellent.

  The manufacturing method of said (d1-1) component and (d1-2) component is not specifically limited, It can manufacture by a well-known method.

  The content of the component (D1) is preferably 0.5 to 10.0 parts by mass, and more preferably 0.5 to 8.0 parts by mass with respect to 100 parts by mass of the component (A). And 1.0 to 8.0 parts by mass. Particularly good lithographic characteristics and resist pattern shapes can be obtained as the lower limit value of the above range is exceeded. The sensitivity can be favorably maintained and the throughput is excellent as the upper limit value of the above-mentioned range or less is achieved.

((D2) ingredient)
The component (D) may contain a nitrogen-containing organic compound component (hereinafter referred to as the component (D2)) which does not correspond to the component (D1).
The component (D2) functions as an acid diffusion control agent and is not particularly limited as long as it does not correspond to the component (D1), and any known one may be used. Among them, aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are preferred.
The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.
Examples of the aliphatic amine, at least one hydrogen atom of ammonia NH _3, amines substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms (the alkyl amine or alkyl alcohol amines) or a cyclic amine.
Specific examples of the alkylamine and the alkyl alcoholamine include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine and n-decylamine; diethylamine, di-n-propylamine, di-amine -Dialkylamines such as n-heptylamine, di-n-octylamine and dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine , Trialkylamines such as tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, tri-n-dodecylamine, etc .; diethanolamine, triethanolamine, diisopropanolamine, Li isopropanolamine, di -n- octanol amines, alkyl alcohol amines tri -n- octanol amine. Among these, trialkylamines having 5 to 10 carbon atoms are more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

The cyclic amine includes, for example, a heterocyclic compound 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 aliphatic monocyclic amines include piperidine, piperazine and the like.
The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and 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.

  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} ethyl] amine, triethanolamine triacetate, etc. are mentioned, and triethanolamine triacetate is preferable.

Further, as the component (D2), an aromatic amine may be used.
As aromatic amines, aniline, pyridine, 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, diphenylamine, triphenylamine, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxy And carbonyl pyrrolidine.

The component (D2) may be used alone or in combination of two or more.
Component (D2) is used usually in the range of 0.01 to 5.0 parts by mass with respect to 100 parts by mass of component (A). By setting it in the above-mentioned range, the resist pattern shape, the stability over time of placing, etc. are improved.

As the component (D), one type may be used alone, or two or more types may be used in combination.
When the resist composition of the present invention contains the component (D), the amount of the component (D) is preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the component (A). The amount is more preferably 12 parts by mass, and further preferably 0.5 to 12 parts by mass. When it is set as a resist composition as it is more than the lower limit of the said range, lithography properties, such as LWR, will improve more. Also, a better resist pattern shape can be obtained. The sensitivity can be favorably maintained and the throughput is excellent as the upper limit value of the above-mentioned range or less is achieved.

[(F) component]
The resist composition of the present invention may contain a fluorine additive (hereinafter referred to as “component (F)”) in order to impart water repellency to the resist film.
Examples of the component (F) include, for example, JP-A-2010-002870, JP-A-2010-032994, JP-A-2010-277043, JP-A-2011-13569, and JP-A-2011-128226. The fluorine-containing polymer compounds described can be used.
More specific examples of the component (F) include polymers having a structural unit (f1) represented by the following formula (f1-1). As the polymer, a polymer (homopolymer) consisting only of a structural unit (f1) represented by the following formula (f1-1); a structural unit (f1) represented by the following formula (f1-1), Copolymer with Structural Unit (a1); Structural Unit (f1) Represented by the Following Formula (f1-1), Structural Unit Derived from Acrylic Acid or Methacrylic Acid, and Structural Unit (a1) It is preferable that it is a copolymer of Here, as the structural unit (a1) to be copolymerized with the structural unit (f1) represented by the following formula (f1-1), 1-ethyl-1-cyclooctyl (meth) acrylate or the above-mentioned formula (a1) The structural unit represented by -2-01) is preferable.

［式中、Ｒは前記同様であり、Ｒｆ^１０２およびＲｆ^１０３はそれぞれ独立して水素原子、ハロゲン原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基を表し、Ｒｆ^１０２およびＲｆ^１０３は同じであっても異なっていてもよい。ｎｆ^１は１〜５の整数であり、Ｒｆ^１０１はフッ素原子を含む有機基である。］

[Wherein, R is as defined above, and Rf ¹⁰² and Rf ¹⁰³ each independently represent a hydrogen atom, a halogen atom, an alkyl group of 1 to 5 carbon atoms, or a halogenated alkyl group of 1 to 5 carbon atoms, Rf ¹⁰² and Rf ¹⁰³ may be the same or different. nf ¹ is an integer of ¹ to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom. ]

In formula (f1-1), R is as defined above. As R, a hydrogen atom or a methyl group is preferable.
Wherein ^(f1-1), the halogen atom of ^{Rf 102} and ^{Rf 103,} a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, a fluorine atom is particularly preferred. Examples of the alkyl group having 1 to 5 carbon atoms of Rf ¹⁰² and ^{Rf 103,} the same alkyl group of 1 to 5 carbon atoms in the R, and a methyl group or an ethyl group is preferred. As the halogenated alkyl group of 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ , specifically, a group in which part or all of hydrogen atoms of the above-mentioned alkyl group of 1 to 5 carbon atoms are substituted with a halogen atom is It can be mentioned. 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. Among them, as Rf ¹⁰² and Rf ¹⁰³ , a hydrogen atom, a fluorine atom or an alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom, a fluorine atom, a methyl group or an ethyl group is preferable.
In formula (f1-1), nf ¹ is an integer of ¹ to 5, preferably an integer of 1 to 3, and more preferably 1 or 2.

In Formula (f1-1), Rf ¹⁰¹ is an organic group containing a fluorine atom, and is preferably a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, and more preferably 1 to 15 carbon atoms. And 1 to 10 carbon atoms are particularly preferred.
Moreover, as for the hydrocarbon group containing a fluorine atom, it is preferable that 25% or more of the hydrogen atoms in the said hydrocarbon group are fluorinated, It is more preferable that 50% or more is fluorinated, 60% or more Fluorination is particularly preferable because the hydrophobicity of the resist film at the time of immersion exposure is increased.
Among them, a fluorinated hydrocarbon group having 1 to 5 carbon atoms is particularly preferable as Rf ¹⁰¹ , and a methyl group, -CH ₂ -CF ₃ , -CH ₂ -CF ₂ -CF ₃ , -CH (CF ₃ ) ₂ And -CH ₂ -CH ₂ -CF ₃ and -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF ₃ are most preferable.

1000-50000 are preferable, as for the weight average molecular weight (Mw) (the polystyrene conversion standard by gel permeation chromatography) of (F) component, 5000-40000 are more preferable, and 10000-30000 are the most preferable. When it is below the upper limit of this range, it has sufficient solubility in a resist solvent to be used as a resist, and when it is above the lower limit of this range, the dry etching resistance and the resist pattern cross-sectional shape are good.
The dispersion degree (Mw / Mn) of the component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

As the component (F), one type may be used alone, or two or more types may be used in combination.
Component (F) is used in a proportion of 0.5 to 10 parts by mass with respect to 100 parts by mass of component (A).

  In the resist composition of the present invention, additives which are optionally miscible, for example, an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, Dyes and the like can be appropriately added and contained.

[(E) ingredient]
In the resist composition of the present invention, particularly in the case of using an acid diffusion controller component other than the component (D0) described above, for the purpose of preventing sensitivity deterioration, and improving the resist pattern shape and storage stability over time. As an optional component, an organic carboxylic acid and at least one compound (E) (hereinafter referred to as component (E)) selected from the group consisting of oxo acids of phosphorus and derivatives thereof 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 preferable.
Examples of phosphorus oxo acids include phosphoric acid, phosphonic acid and phosphinic acid. Among these, phosphonic acid is particularly preferable.
Examples of derivatives of oxo acids of phosphorus include esters in which a hydrogen atom of the above oxo acid is substituted with a hydrocarbon group, and examples of the hydrocarbon group include alkyl groups having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like can be mentioned.
Examples of derivatives of phosphoric acid include phosphoric acid di-n-butyl ester, phosphoric acid esters such as phosphoric acid diphenyl ester, and the like.
Examples of derivatives of phosphonic acid include phosphonic acid dimethyl ester, phosphonic acid di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid esters such as phosphonic acid dibenzyl ester, and the like.
Examples of phosphinic acid derivatives include phosphinic acid esters and phenylphosphinic acid.
As the component (E), one type may be used alone, or two or more types may be used in combination.
Component (E) is used usually in the range of 0.01 to 5.0 parts by mass with respect to 100 parts by mass of component (A).

[(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 component (S)).
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, and any one of conventionally 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 (MEK), cyclohexanone, methyl-n-pentyl ketone (2-heptanone), methyl isopentyl ketone, etc. ethylene glycol, diethylene glycol, propylene glycol, Polyhydric alcohols such as propylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, the above polyhydric alcohols or compounds having the ester bond Monoalkyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether Derivatives of polyhydric alcohols such as compounds having an ether bond [in these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) are preferred]; cyclic ethers such as dioxane; Esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; anisole, ethyl benzyl ether, cresyl methyl Ether, diphenylether, dibenzylether, phenetole, butylphenylether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene And aromatic organic solvents such as dimethyl sulfoxide (DMSO).
These organic solvents may be used alone or in combination of two or more.
Among them, PGMEA, PGME, γ-butyrolactone, and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The compounding ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, etc., but is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be in the range.
More specifically, in the case of blending EL or cyclohexanone as a polar solvent, the mass ratio of PGMEA: EL or cyclohexanone 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 1: 9-9: 1, More preferably, 2: 8-8: 2, More preferably, 3: 7-7: It is three.
In addition, as the component (S), mixed solvents of at least one selected from PGMEA and EL and γ-butyrolactone are also preferable. In this case, the mass ratio of the former and the latter is preferably 70:30 to 95: 5 as the mixing ratio.
The amount of the component (S) to be used is not particularly limited, and can be appropriately set according to the applied film thickness, at a concentration that can be applied to a substrate or the like. Generally, it is used so that the solid content concentration of the resist composition is in the range of 1 to 20% by mass, preferably 2 to 15% by mass.

  In the resist composition of the present invention, additives which are optionally miscible, for example, an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, an antihalation agent, Dyes and the like can be appropriately added and contained.

The resist composition of the present invention is excellent in lithography properties while maintaining high sensitivity. The reason is presumed as follows.
The resist composition of the present invention comprises a polymer compound (A1) having a structural unit (a0) represented by general formula (a0-1), and the acid generator component (B) has a general formula (b-1) Or a compound represented by (b-2).
Since the structural unit (a0), which is an acid dissociable monomer, has an ether bond in the vicinity of the ester group and attracts a proton, the affinity with the acid is enhanced and dissociation by the acid is promoted, so high sensitivity is achieved It is thought that can be done.
Furthermore, it is considered that good sensitivity and lithography properties can be maintained by combining the acid generator component (B) in which the generated acid is short diffusion.
That is, the resist composition of the present invention is very useful because it can achieve both high sensitivity and improvement in lithography properties.

«Method for forming resist pattern»
The method for forming a resist pattern according to the second aspect of the present invention comprises the steps of: forming a resist film on a support using the resist composition of the present invention; exposing the resist film; It includes a step of developing to form a resist pattern.
The resist pattern formation method of the present invention can be performed, for example, as follows.
First, the resist composition of the present invention is coated on a support by a spinner or the like, and baked (post applied bake (PAB)) treatment, for example, at a temperature condition of 80 to 150 ° C. for 40 to 120 seconds, preferably 60. Apply for about 90 seconds to form a resist film.
Next, the resist film is exposed to light through a mask (mask pattern) on which a predetermined pattern is formed using an exposure apparatus such as an ArF exposure apparatus, an electron beam drawing apparatus, an EUV exposure apparatus, or the like. After selective exposure by drawing etc. by direct irradiation of electron beam not through, etc., baking (post-exposure baking (PEB)) treatment is carried out, for example, for 40 to 120 seconds at a temperature condition of 80 to 150 ° C., preferably 60 to 60 ° C. Apply for 90 seconds.
Next, the resist film is developed.
The development processing is performed using an alkaline developer in the case of an alkali development process and using a developer (organic developer) containing an organic solvent in the case of a solvent development process.
After the development process, a rinse process is preferably performed. In the case of the alkali development process, water rinse using pure water is preferable, and in the case of the solvent development process, it is preferable to use a rinse solution containing an organic solvent.
In the case of a solvent development process, after the development process or rinse process, a process of removing the developer or rinse solution adhering on the pattern with a supercritical fluid may be performed.
After development processing or rinse processing, drying is performed. Further, in some cases, a bake treatment (post bake) may be performed after the development treatment. Thus, a resist pattern can be obtained.

The support is not particularly limited, and conventionally known ones can be used, and examples thereof include a substrate for an electronic component, and a substrate on which a predetermined wiring pattern is formed. More specifically, a silicon wafer, a metal substrate such as copper, chromium, iron, aluminum or the like, a glass substrate, etc. may be mentioned. As a material of the wiring pattern, for example, copper, aluminum, nickel, gold or the like can be used.
In addition, as the support, an inorganic and / or organic film may be provided on the substrate as described above. Examples of inorganic films include inorganic antireflective films (inorganic BARCs). Examples of the organic film include organic films such as an organic antireflective film (organic BARC) and a lower organic film in a multilayer resist method.
Here, in the multilayer resist method, at least one organic film (lower organic film) and at least one resist film (upper resist film) are provided on a substrate, and a resist pattern formed on the upper resist film is used as a mask. It is a method of patterning the lower organic film, and is said to be able to form a pattern with a high aspect ratio. That is, according to the multilayer resist method, since the required thickness can be secured by the lower layer organic film, the resist film can be thinned, and a fine pattern with a high aspect ratio can be formed.
In the multilayer resist method, basically, a method of forming a two-layer structure of an upper layer resist film and a lower layer organic film (bilayer resist method), and one or more intermediate layers between the upper layer resist film and the lower layer organic film It is divided into the method (three-layer resist method) of forming a multilayer structure of three or more layers provided with (metal thin film etc.).

The wavelength used for 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. It can be done using radiation. The resist composition is highly useful for KrF excimer laser, ArF excimer laser, EB or EUV.

The exposure method of the resist film may be a normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or may be a liquid immersion exposure (Liquid Immersion Lithography).
In immersion exposure, the space between the resist film and the lowermost lens of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than that of air, and exposure (immersion exposure) is performed in that state It is an exposure method.
As the immersion medium, a solvent having a refractive index which is larger than the refractive index of air and smaller than the refractive index of the resist film to be exposed is preferable. The refractive index of the 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, a hydrocarbon-based solvent and the like.
Specific examples of the fluorine-based inert liquid include fluorine-based compounds such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as main components. A liquid etc. are mentioned, The thing of 70-180 degreeC of boiling points is preferable, and the thing of 80-160 degreeC is 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 completion of exposure.
As the fluorine-based inert liquid, particularly preferred is a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms. Specific examples of perfluoroalkyl compounds include perfluoroalkyl ether compounds and perfluoroalkylamine compounds.
Furthermore, specifically, as the perfluoroalkylether compound, perfluoro (2-butyl-tetrahydrofuran) (boiling point 102 ° C.) can be mentioned, and as the perfluoroalkylamine compound, perfluorotributylamine ( Boiling point 174 ° C.) can be mentioned.
Water is preferably used as the immersion medium from the viewpoints of cost, safety, environmental problems, versatility and the like.

As an alkali developing solution used for image development process by an alkali developing process, 0.1-10 mass% tetramethyl ammonium hydroxide (TMAH) aqueous solution is mentioned, for example.
The organic solvent contained in the organic developer used for development in the solvent development process may be any solvent that can dissolve the component (A) (component (A) before exposure), and among known organic solvents It can be selected appropriately. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents and hydrocarbon solvents can be used.
Known additives can be blended into the organic developer as required. Examples of the additive include surfactants. The surfactant is not particularly limited, and for example, an ionic or non-ionic fluorine-based and / or silicon-based surfactant can be used.
When mix | blending surfactant, the compounding quantity is 0.001-5 mass% normally with respect to whole quantity of an organic type developing solution, 0.005-2 mass% is preferable, and 0.01-0. 5 mass% is more preferable.

  The development processing can be carried out by a known development method, for example, a method of immersing the support in a developer for a fixed time (dip method), a developer is raised on the surface of the support by surface tension and rested for a fixed time Method (paddle method), method of spraying the developer on the surface of the support (spray method), coating the developer while scanning the developer coating nozzle at a constant speed on the support rotating at a constant speed The following method (dynamic dispensing method) and the like can be mentioned.

  The rinse process (washing process) using the rinse liquid can be implemented by the well-known rinse method. The method includes, for example, a method of continuously applying a rinse solution on a support rotating at a constant speed (rotation coating method), a method of immersing a support in a rinse solution for a certain time (dip method), a support surface And a method of spraying a rinse liquid (spray method).

  EXAMPLES Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited to the following examples.

[Polymer synthesis example]
In a separable flask connected to a thermometer, a reflux condenser and a nitrogen inlet, 26.40 g of methyl ethyl ketone (MEK) was placed and heated to 80 ° C. Here, 11.00 g (64.65 mmol) of the compound (1), 33.78 g (149.27 mmol) of the compound (2), 5.00 g (21.16 mmol) of the compound (3), 14. as a polymerization initiator. A solution of 10 mmol of dimethyl azobisisobutyrate (V-601) dissolved in 74.67 g of MEK was added dropwise over 4 hours under a nitrogen atmosphere.
After completion of the dropwise addition, the reaction solution was heated and stirred for 1 hour, and then the reaction solution was cooled to room temperature. The resulting reaction polymerization solution was added dropwise to a large amount of n-heptane to precipitate a polymer. The precipitated white powder was separated by filtration and dried to obtain 35 g of a polymer compound A-1.
The mass average molecular weight (Mw) in terms of standard polystyrene of the polymer compound A-1 determined by GPC was 67,000, and the molecular weight distribution (Mw / Mn) was 1.6.
Further, the molar ratio of the compounds (1), (2) and (3) determined by carbon 13 nuclear magnetic resonance spectrum (600 MHz ¹³ C-NMR) is (1) / (2) / (3) = 30/60 It was / 10.
In the same manner, polymers A-2 to A-11 having the composition ratios shown in Table 1 were synthesized using the compounds shown below.

<Preparation of Resist Composition>
(Examples 1 to 17, Comparative Examples 1 to 8)
The resist composition of each example was prepared by mixing and dissolving each component shown in Tables 2-3. However, Example 9 and Example 16 are all reference examples.

In Tables 2 to 3, each abbreviation has the following meaning. The numerical values in [] are compounding amounts (parts by mass).
A-1 to A-11: the above-mentioned polymer compounds A1-1 to A1-11.
B-1 to B-4: An acid generator comprising a compound represented by the following chemical formula (B) -1 to (B) -4.
D-1: An acid diffusion control agent comprising a compound represented by the following chemical formula (D) -1.
E-1: salicylic acid.
F-1: a fluorine-containing polymer compound represented by the following chemical formula (F) -1.
S-1: mixed solvent of PGMEA / PGME / cyclohexanone (mass ratio 45/30/25).

<Formation 1 of resist pattern>
[Formation of contact hole pattern]
A 90 nm thick organic antireflective film was formed on a 12-inch silicon wafer.
The resist compositions of Examples 1 to 13 and Comparative Examples 1 to 5 are respectively coated on the organic antireflective film using a spinner, and prebaked at 110 ° C. for 60 seconds (PAB) on a hot plate. The treatment was performed and dried to form a resist film having a film thickness of 90 nm.
Next, with respect to the resist film, a liquid immersion ArF exposure apparatus NSR-S609B (manufactured by Nikon; NA (numerical aperture) = 1.07, cross-pole, immersion medium: water) through a photomask. And ArF excimer laser (193 nm) were selectively irradiated.
Thereafter, a post-exposure heat treatment was performed at 100 ° C. for 45 seconds.
Next, alkaline development was performed for 10 seconds at 23.degree. C. using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.).
As a result, except for Comparative Example 3, contact hole patterns (hereinafter referred to as “CH patterns”) were formed in which holes of 75 nm in diameter were arranged at equal intervals (pitch 145 nm).

<Formation 2 of resist pattern>
[Formation of line and space pattern]
A 90 nm thick organic antireflective film was formed on a 12-inch silicon wafer.
The resist compositions of Examples 1 to 13 and Comparative Examples 1 to 5 are respectively coated on the organic antireflective film using a spinner, and prebaked at 110 ° C. for 60 seconds (PAB) on a hot plate. The treatment was performed and dried to form a resist film having a film thickness of 90 nm.
Next, with respect to the resist film, the ArF exposure apparatus for immersion NSR-S609B (manufactured by Nikon; NA (numerical aperture) = 1.07, Dipole, immersion medium: water) through a photomask and ArF. Excimer laser (193 nm) was selectively irradiated.
Thereafter, a post-exposure heat treatment was performed at 100 ° C. for 45 seconds.
Next, alkaline development was performed for 10 seconds at 23.degree. C. using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) "NMD-3" (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.).
As a result, in any of the examples, a line and space pattern (hereinafter also referred to as “LS pattern”) having a line width of 40 nm and a pitch width of 80 nm was formed.

<Formation of resist pattern 3: solvent development negative type>
Examples 14 to 17 and Comparative Examples 6 to 8
An organic antireflection film composition "ARC 29" (trade name, manufactured by Brewer Science Inc.) is applied on an 8-inch silicon wafer using a spinner, baked on a hot plate at 205 ° C. for 60 seconds, and dried. Thus, an organic antireflective film having a thickness of 82 nm was formed.
Next, the resist compositions of Examples 14 to 17 and Comparative Examples 6 to 6 are coated on the film using a spinner, respectively, and prebaked (PAB) on a hot plate at 90 ° C. for 60 seconds. And dried to form a resist film having a thickness of 100 nm.
Next, an ArF excimer laser (193 nm) is exposed to the resist film through a mask pattern (6% halftone) by an exposure apparatus NSR-S609B (Nikon NA = 1.07 Dipole 0.97 / 0.78 with polano). Selectively. Each exposure amount is written together in Table 6.
Subsequently, solvent development was performed with butyl acetate for 16 seconds at 23 ° C., and the mixture was shaken off and dried.
In any of the examples, a contact hole pattern having a hole diameter of 55 nm / pitch 110 nm was formed.

[Evaluation of optimum exposure (Eop)]
The optimum exposure amount Eop (mJ / cm ² ) at which the LS pattern of the target size was formed by the above-described resist pattern forming method was determined. The results are shown in Tables 4 to 5 as "sensitivity (mJ / cm ² )".
[Evaluation of circularity (Circularity)]
The 25 holes in the above CH pattern are observed from above by a length measurement SEM (scanning electron microscope, accelerating voltage 300 V, trade name: S-9380, manufactured by Hitachi High-Technologies Corporation), and from the center to the outer edge of each hole The distance of was measured in 24 directions. A triple value (3σ) of the standard deviation (σ) calculated from the measurement results was determined. The results are shown in Tables 4 and 6.
The smaller the value of 3σ obtained in this manner, the higher the roundness of the hole.
[Evaluation of depth of focus (DOF)]
In the above <Resist pattern formation 1> and <Resist pattern formation 2>, the focus is appropriately shifted up and down with the optimal exposure amount (Eop (mJ / cm ² )) at which the CH pattern or LS pattern is formed. A CH pattern or an LS pattern was formed in the same manner as in the pattern formation 1> to <resist pattern formation 3>. At this time, the depth of focus (DOF, unit: μm) that the CH pattern or LS pattern can form within the dimensional change rate of the target dimension ± 5% was determined. The results are shown in Tables 4 to 6. In Tables 3 to 4, when the DOF is 0.000, an image is formed only at the center focus, and when the focus is shifted, the image disappears.
[Evaluation of LWR (Line Wise Roughness)]
In a line-and-space pattern having a line width of 40 nm and a pitch width of 80 nm, formed by the <resist pattern formation 2>, a length-measuring SEM (scanning electron microscope, accelerating voltage 300 V, trade name: S-9380, Hitachi High-Technologies The line width is measured at 400 points in the longitudinal direction of the line, and the tripled value (3s) of the standard deviation (s) is obtained from the result, and the LWR is obtained by averaging the values for 3s at 400 points. Calculated as a scale to show. The results are shown in Table 5 as "LWR (nm)".
The smaller the value of 3 s, the smaller the roughness of the line width, which means that a line and space pattern of more uniform width is obtained.

  As shown in the above results, the resist compositions of the examples were higher in sensitivity and superior in lithography properties than the resist compositions of the comparative examples.

Claims (2)

A resist composition which generates an acid upon exposure and whose solubility in a developer changes by the action of the acid,
Contained by the action of an acid and base component which solubility change in a developing solution (A), 1 acid generator component that generates acid on exposure and (B),
The base component (A) has a structural unit (a0) represented by the following general formula (a0-1) and a structural unit (a2 ′) represented by the following general formula (a2′-1) Containing a polymer compound (A1),
The acid generator component (B), a resist composition which comprises a compound represented by the following general formula (b-1).

[In the formula (a0-1), R represents a hydrogen atom, an alkyl group of 1 to 5 carbon atoms or a halogenated alkyl group of 1 to 5 carbon atoms, Ya ⁰¹ is a divalent linking group, and Za ⁰¹ is bonded to Xa ⁰¹ Group which forms an alicyclic group by removing two or more hydrogen atoms from cyclopentane together with carbon atoms, Xa ⁰¹ is a branched alkylene group having 2 to 6 carbon atoms, and Ra ⁰¹ is 1 to 10 carbon atoms Aliphatic hydrocarbon group, n is 0-2. ]

[In the formula (a2′-1), R represents a hydrogen atom, an alkyl group of 1 to 5 carbon atoms, or a halogenated alkyl group of 1 to 5 carbon atoms, and Ya ²¹ represents a single bond or a divalent linking group , La ²¹ is —O—, —COO—, or —OCO—. However, when La ²¹ is —O—, Ya ²¹ does not become —CO—. Ra ²¹ represents a lactone-containing cyclic group represented by the following formula (a2-r-1) or (a2-r-2), or a -SO ₂ -containing ring represented by the following formula (a5-r-1) It is a formula group. ]

Wherein (a2-r-1) and (a2-r-2), Ra '21 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxyl group, -COOR ", - OC (= O) R ′ ′, a hydroxyalkyl group or a cyano group; R ′ ′ is a hydrogen atom or an alkyl group; A ′ ′ is an oxygen atom or an alkylene group having 1 to 5 carbon atoms which may contain a sulfur atom , Oxygen atom or sulfur atom. n 'is an integer of 0-2. Formula (a5-r-1) in, Ra ^'51 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxyl group, -COOR ", - OC (= O) R", hydroxy R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom. Each * represents a bond with La ²¹ . ]

[In Formula (b-1), R ¹⁰¹ is a cyclic group which may have a substituent. R ¹⁰² is a fluorine atom or a fluorinated alkyl group of 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ¹⁰¹ is a single bond, an alkylene group or a fluorinated alkylene group. m is an integer of 1 or more, and M ' ^{m +} is an m-valent organic cation. ] A resist pattern comprising a step of forming a resist film using the resist composition according to claim 1 on a support, a step of exposing the resist film, and a step of developing the resist film to form a resist pattern Formation method.