KR101933786B1 - Resist composition and pattern forming process - Google Patents

Abstract

(식에서, R¹은 수소 원자 또는 메틸기를 나타낸다. R²는 수소 원자, 탄소수 1∼8의 직쇄상, 분기상 또는 환상의 알킬기, 탄소수 2∼6의 직쇄상, 분기상 또는 환상의 아실기, 또는 탄소수 2∼6의 직쇄상, 분기상 또는 환상의 알콕시카르보닐기를 나타낸다. X¹은 단결합, 페닐렌, 나프틸렌, 또는 에스테르기, 에테르기 또는 락톤환을 포함하는 탄소수 1∼12의 연결기를 나타낸다. a는 0<a<1.0을 만족하는 양수를 나타낸다.)An object of the present invention is to provide a resist material which reduces acid diffusion, has a high resolution exceeding a conventional resist material, has a small edge roughness (LER, LWR) and gives a good pattern shape, Lt; / RTI &gt;
[MEANS FOR SOLVING PROBLEMS] A resist comprising a base resin comprising a repeating unit represented by the following formula (a) and a repeating unit containing a group whose polarity is changed by an acid and having a weight average molecular weight of 1,000 to 500,000 material:

(Wherein, R ¹ represents a hydrogen atom or a methyl group. R ² represents a hydrogen atom, a straight-chain, branched or cyclic acyl group having 1 to 8 carbon atoms of straight-chain, branched or cyclic alkyl group of carbon number 2 to 6, Or a straight, branched or cyclic alkoxycarbonyl group having 2 to 6 carbon atoms, X ¹ is a single bond, phenylene, naphthylene, or a linking group having 1 to 12 carbon atoms including an ester group, an ether group or a lactone ring, A represents a positive integer satisfying 0 < a &lt; 1.0.

Description

RESIST MATERIAL AND METHOD FOR FORMING RESIST COMPOSITION AND PATTERN FORMING PROCESS

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

With the increasingly high integration and high speed of LSI, the pattern rule is becoming finer. In particular, the expansion of the flash memory market and the increase in memory capacity are leading to miniaturization. As a state-of-the-art micromachining technology, ArF lithography has mass-produced 65 nm node devices, and preparations for mass production of 45 nm nodes by the next generation of ArF immersion lithography are underway. As the next-generation 32 nm node, immersion lithography using an ultra-high NA lens combined with a liquid having a refractive index higher than that of water, a high refractive index lens and a high refractive index resist film, extreme ultraviolet (EUV) lithography with a wavelength of 13.5 nm, Patterning lithography) and the like are candidates, and studies are underway.

Resist materials based on polyhydroxystyrene, which are mainly composed of hydrocarbons, have been studied since extremely high-energy, high-energy radiation such as electron beam (EB) or X-ray is hardly absorbed by hydrocarbons used in resist materials .

As an exposure apparatus for mask fabrication, an exposure apparatus using EB has been used instead of an exposure apparatus using a laser beam in order to increase the line width accuracy. In addition, miniaturization can be further achieved by raising the acceleration voltage of the electron gun. Therefore, the mainstream is 30 kV at 10 kV, and 50 kV in recent years, and studies of 100 kV are underway.

Here, with the increase of the acceleration voltage, the reduction of the resist film has been problematic. When the acceleration voltage rises, the influence of the forward scattering in the resist film becomes small, so that the contrast of the electron imaging energy is improved and the resolution and dimensional controllability are improved. Since electrons pass through the resist film without intervention, The sensitivity of the film decreases. Since the mask exposure device exposes with a single crease, the lowering of the sensitivity of the resist film leads to a decrease in productivity, which is not preferable. Chemically amplified resist materials have been studied from the viewpoint of high sensitivity.

With the progress of micronization, blurring of the image due to acid diffusion becomes a problem. In order to ensure resolution in a fine pattern having a dimension size of 45 nm or less, it has been proposed that not only improvement in dissolution contrast as proposed in the past, but also control of acid diffusion is important (Non-Patent Document 1). However, since the chemically amplified resist material raises the sensitivity and contrast by diffusion of acid, sensitivity and contrast are significantly lowered when the post-exposure bake (PEB) temperature or time is shortened and acid diffusion is suppressed to an extreme limit.

The sensitivity, the resolution, and the triangle tradeoff of the edge roughness are shown. Here, in order to improve the resolution, it is necessary to suppress the acid diffusion, but when the acid diffusion distance becomes short, the sensitivity decreases.

It is effective to suppress the acid diffusion by adding an acid generator generating a bulky acid. Thus, it has been proposed to incorporate in the polymer a repeating unit derived from an onium salt containing a polymerizable unsaturated bond as an acid generator. Patent Document 1 proposes a sulfonium salt or an iodonium salt containing a polymerizable unsaturated bond which generates a specific sulfonic acid. Patent Document 2 proposes a sulfonium salt in which a sulfonic acid is directly connected to a main chain.

Studies have been made for suppressing acid diffusion by a method other than a bulk acid generating agent. Patent Documents 3 to 8 disclose adhesion groups containing nitrogen atoms. For the control of acid diffusion, the presence of electron pairs of nitrogen atoms is effective. However, the nitrogen atom not only prevents acid diffusion but also suppresses the acid catalyst reaction. In this case, there arises a problem that the contrast is lowered because the deprotection reaction does not proceed or the rate is slow even if it progresses.

[Patent Document 1] JP-A-2006-045311 [Patent Document 2] JP-A-2006-178317 [Patent Document 3] Japanese Patent Laid-Open Publication No. 2011-203656 [Patent Document 4] International Publication No. 2011/024953 [Patent Document 5] International Publication No. 2012/043102 [Patent Document 6] International Publication No. 2013/129342 [Patent Document 7] JP-A-2012-62371 [Patent Document 8] Japanese Patent Application Laid-Open No. 2012-197382

[Non-Patent Document 1] SPIE Vol. 6520 65203L-1 (2007)

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a resist composition which reduces acid diffusion, has a high resolution exceeding a conventional resist material, has a small edge roughness (LER, LWR) It is an object of the present invention to provide a pattern forming method using a resist material.

The inventors of the present invention have conducted intensive investigations to obtain a resist material having a high sensitivity, a high resolution and an edge roughness as recently desired, and as a result, it has been found that a polymer containing a repeating unit containing a succinimide structure is used as a resist material, It is very effective to use it as a base resin of a chemically amplified resist material.

The present inventors have also found that, in order to suppress acid diffusion and improve dissolution contrast, a polymer containing a repeating unit containing a predetermined repeating unit containing a succinimide structure and a group whose polarity is changed by an acid, , Particularly, as a base resin of a chemically amplified resist material, has a high sensitivity, a high alkaline dissolution rate contrast before and after exposure, high effect of suppressing acid diffusion, high resolution, and a pattern shape after exposure and edge roughness It is possible to obtain a resist material suitable for forming a fine pattern, particularly a chemically amplified resist material, for a good LSI manufacturing, especially for a super LSI or a photomask.

The resist material of the present invention is particularly suitable for use as a resist material because it can increase decomposition efficiency of an acid generator and thus has a high sensitivity, a high effect of suppressing acid diffusion, a high resolution, a small edge roughness, The pattern shape after exposure is good. Therefore, they are very effective as a resist material for a super LSI and a mask pattern forming material because of their excellent properties.

That is, the present invention provides the following resist material and a pattern forming method.

1. A resist composition comprising a base resin comprising a polymer having a repeating unit represented by the following formula (a) and a repeating unit having a group whose polarity is changed by an acid, and having a weight average molecular weight of 1,000 to 500,000:

(Wherein, R ¹ represents a hydrogen atom or a methyl group. R ² represents a hydrogen atom, a straight-chain, branched or cyclic acyl group having 1 to 8 carbon atoms of straight-chain, branched or cyclic alkyl group of carbon number 2 to 6, Or a straight, branched or cyclic alkoxycarbonyl group having 2 to 6 carbon atoms, X ¹ is a single bond, a phenylene group, a naphthylene group, or a linking group having 1 to 12 carbon atoms including an ester group, an ether group or a lactone ring A represents a positive integer satisfying 0 < a < 1.0.

2. The resist material of claim 1, wherein the polarity change due to the acid is due to the elimination reaction.

3. The resist material of 1 or 2, wherein the repeating unit containing a group whose polarity is changed by an acid includes a carboxyl group or a phenolic hydroxy group substituted with an acid labile group.

4. A resist composition of 3 wherein the repeating unit containing a group whose polarity is changed by an acid is represented by the following formula (b1) or (b2):

(Wherein R ³ and R ⁵ each independently represents a hydrogen atom or a methyl group, R ⁴ and R ⁸ each independently represent an acid labile group, and R ⁶ represents a single bond or a straight or branched R ⁷ represents a hydrogen atom, a fluorine atom, a trifluoromethyl group, a cyano group, a linear, branched or cyclic alkyl group or alkoxy group having 1 to 6 carbon atoms, or a linear, branched or cyclic alkyl group having 2 to 7 carbon atoms, An acyl group, an acyloxy group or an alkoxycarbonyl group, p represents 1 or 2, q represents an integer of 0 to 4, Y ¹ represents a single bond, a phenylene group, a naphthylene group or It represents a linking group having 1 to 12 carbon atoms, including an ester group, an ether group or lactone ring. Y ² represents a single bond, -C (= O) -O-, or -C (= O) -NH-. b1 And b2 represent positive numbers satisfying 0? B1 <1.0, 0? B2 <1.0, and 0 <b1 + b2 <1.0.

5. The resist material of 1 or 2, wherein the repeating unit containing a group whose polarity is changed by an acid is a repeating unit which is changed from a hydrophilic to a hydrophobic by a dehydration reaction by an acid.

6. A resist composition of 5 wherein the repeating unit containing a group whose polarity is changed by an acid is derived from a monomer represented by the following formula:

(In the formula, R ⁹ represents a hydrogen atom or a methyl group.)

Wherein the polymer is at least one selected from the group consisting of a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether group, an ester group, a sulfonate group, a cyano group, = O) -G- (wherein G is -S- or -NH-). &Lt; / RTI &gt;

8. The resist composition according to any one of 1 to 7, wherein the polymer further comprises at least one repeating unit selected from the following formulas (d1) to (d3):

(Wherein, R ^20, R ²⁴ and R ²⁸ each independently represent a hydrogen atom or a methyl group, R ²¹ represents a single bond, phenylene group, -OR ^A -., Or ^{-C (= O) -Y 0 -R} A - , Y ⁰ represents -O- or -NH-, R ^A represents a linear, branched or cyclic alkylene group having 1 to 6 carbon atoms which may contain a carbonyl group, an ester group, an ether group or a hydroxy group, or R ²² , R ²³ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁹ , R ^30, and R ³¹ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a linear, branched or cyclic alkenylene group having 2 to 6 carbon atoms, A linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may contain a carbonyl group, an ester group, an ether group or a hydroxy group, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 20 carbon atoms or a mercaptophenyl group It represents. Z ¹ represents a single bond, or an ether group, and can include an ester group or lactone ring Also represents an group having 1 to 12 carbon atoms of straight-chain, branched or straight chain alkylene group of 2 to 12 carbon atoms or a cyclic, branched or cyclic alkenylene group, or a 6 to 10 carbon atoms, arylene. Z ² is a single -OR ³² -, or -C (= O) -Z ³ -R ³² -, Z ³ represents -O- or -NH-, and R ³ represents a hydrogen atom or a methyl group, , R ³² represents a linear, branched or cyclic, alkylene or alkenylene group having 1 to 12 carbon atoms which may contain a carbonyl group, an ester group, an ether group or a hydroxyl group, or a phenylene group, M ^- represents an unsubstituted D1 to d3 represent positive numbers satisfying 0? D1? 0.5, 0? D2? 0.5, 0? D3? 0.5, and 0 <d1 + d2 + d3?

9. Resist material according to any one of 1 to 8, further comprising an acid generator and an organic solvent.

10. A resist composition according to any one of claims 1 to 9, further comprising a basic compound and / or a surfactant.

11. A pattern forming method comprising a step of applying a resist material of any one of 1 to 10 onto a substrate, a step of exposing the substrate to a high energy beam after the heat treatment, and a step of developing using a developer.

12. The pattern formation method according to 11, wherein the high energy ray is an i-line, a KrF excimer laser, an ArF excimer laser, EB, or an EUV in a wavelength range of 3 to 15 nm.

The resist material of the present invention has high effect of suppressing the diffusion of acid, has high resolution, and has good pattern shape and edge roughness after exposure. Therefore, it is particularly suitable as a material for forming a fine pattern of a photomask for ultra-LSI fabrication or EB imaging, or as a pattern forming material for i-line, KrF excimer laser, ArF excimer laser, EB or EUV exposure.

Further, the resist material of the present invention, particularly the chemically amplified resist material, can be used not only for lithography in the formation of a semiconductor circuit, but also for formation of a mask circuit pattern, or formation of a micromachine and a thin film magnetic head circuit.

[Resist material]

[Base resin]

The resist composition of the present invention is a resist composition comprising a polymer comprising a repeating unit represented by the following formula (a) (hereinafter also referred to as a repeating unit a) and a repeating unit including a group whose polarity is changed by an acid ) As a base resin:

In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² represents a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, a linear, branched or cyclic acyl group having 2 to 6 carbon atoms, or a linear, branched or cyclic alkyl group having 2 to 6 carbon atoms Lt; / RTI &gt; alkoxycarbonyl group. X ¹ represents a single bond, a phenylene group, a naphthylene group, or a linking group having 1 to 12 carbon atoms including an ester group, an ether group or a lactone ring. a represents a positive integer satisfying 0 < a &lt; 1.0.

The monomer (Ma) that gives the repeating unit (a) includes those represented by the following formula (Ma).

(Wherein R ¹ , R ² and X ¹ are as defined above).

The monomer Ma can be synthesized, for example, by a reaction between a compound represented by the following formula (a1) and a compound represented by the following formula (a2).

X ² represents a halogen atom such as a hydrogen atom, a chlorine atom, a bromine atom or the like, or a group represented by the following formula (a3): wherein R ¹ , R ² and X ¹ are as defined above.

(In the formula, R ¹ and X ¹ are as defined above, and the broken line represents the number of bonds.)]

Examples of the monomer Ma include, but are not limited to, those shown below. In the following formula, R ¹ is the same as the above.

The repeating unit a is characterized in that it contains a succinimide structure. The amide group or the carbamate group containing both a nitrogen atom and an oxygen atom has a drawback that the effect of suppressing the acid diffusion is too high to inhibit the deprotection reaction but the succinimide structure has two carbonyl groups around the nitrogen atom The basicity of the nitrogen atom is low, so that the deprotection reaction by the acid catalyst is not inhibited. Thus, the effect of suppressing acid diffusion by asymmetric electrons of nitrogen atoms is high. Adhesion can be ensured by three carbonyl groups, and acid diffusion can be suppressed by asymmetric electrons of nitrogen atoms, whereby pattern collapse and edge roughness (LWR) can be reduced.

Examples of the repeating unit including a group in which the polarity is changed by the acid (hereinafter also referred to as repeating unit b) include a repeating unit containing a carboxyl group or phenolic hydroxy group substituted with an acid labile group. As such a repeating unit, a repeating unit represented by the following formula (b1) (hereinafter also referred to as a repeating unit b1) or a repeating unit represented by the following formula (b2) (hereinafter also referred to as a repeating unit b2) is preferable. When the repeating units b1 and / or b2 are used, the resist material of the present invention can be used as a positive resist material for obtaining a positive pattern by alkali development, or as a negative resist material for obtaining a negative pattern by organic solvent development have.

In the formula, R ³ and R ⁵ each independently represent a hydrogen atom or a methyl group. R ⁴ and R ⁸ each independently represent an acid labile group. R ⁶ represents a single bond or a linear or branched alkylene group having 1 to 6 carbon atoms. R ⁷ represents a hydrogen atom, a fluorine atom, a trifluoromethyl group, a cyano group, a linear, branched or cyclic, alkyl group or alkoxy group having 1 to 6 carbon atoms, or a linear, branched or cyclic , An acyl group, an acyloxy group or an alkoxycarbonyl group. p represents 1 or 2; q represents an integer of 0 to 4; Y ¹ represents a single bond, phenylene, naphthylene, or a linking group having 1 to 12 carbon atoms including an ester group, an ether group or a lactone ring. Y ² represents a single bond, -C (= O) -O-, or -C (= O) -NH-. b1 and b2 represent positive numbers satisfying 0? b1 <1.0, 0? b2 <1.0, and 0 <b1 + b2 <1.0.

As the monomer Mb1 which gives the repeating unit b1, those represented by the following formula (Mb1) may be mentioned. As the monomer Mb2 for giving the repeating unit b2, those represented by the following formula (Mb2) may be mentioned.

(In the formula, R ³ to R ⁸ , Y ¹ , Y ² , p and q are as defined above.)

Examples of the linking group having 1 to 12 carbon atoms including a lactone ring represented by Y ¹ include the following ones.

Examples of the monomer Mb1 include, but are not limited to, those shown below. In the following formulas, R ³ and R ⁴ are as defined above.

Examples of the monomer Mb2 include, but are not limited to, those shown below. In the following formulas, R ⁵ and R ⁸ are the same as above.

The acid labile groups represented by R ⁴ in the formula (Mb 1) and R ⁸ in the formula (Mb 2) are selected in various ways, but they may be the same or different, and JP-A Nos. 2013-80033 and 2013-83821 An acid labile group described in the publication may be used.

Typically, those represented by the following formulas can be mentioned.

In the formula, R ⁵¹ and R ⁵⁴ each independently represent a monovalent hydrocarbon group of 1 to 40 carbon atoms, particularly 1 to 20 carbon atoms, such as a linear, branched or cyclic alkyl group, and a hetero atom such as oxygen, sulfur, May be included. R ⁵² and R ⁵³ each independently represent a hydrogen atom, or a monovalent hydrocarbon group such as a straight, branched or cyclic alkyl group having 1 to 20 carbon atoms, and may contain a hetero atom such as sulfur, nitrogen or fluorine. a5 represents an integer of 0 to 10, particularly 1 to 5; R ⁵² and R ⁵³ , R ⁵² and R ⁵⁴ , or R ⁵³ and R ⁵⁴ may bond to each other to form a carbon atom or a carbon atom and an oxygen atom having 3 to 20 carbon atoms, preferably 4 to 16 carbon atoms A ring, especially an alicyclic ring, may be formed.

R ⁵⁵ , R ⁵⁶ and R ⁵⁷ each independently represent a monovalent hydrocarbon group such as a straight, branched or cyclic alkyl group having 1 to 20 carbon atoms, and may contain a hetero atom such as oxygen, sulfur, nitrogen, fluorine or the like . R ⁵⁵ and R ⁵⁶ , R ⁵⁵ and R ⁵⁷ , or R ⁵⁶ and R ⁵⁷ are bonded to each other to form a ring having 3 to 20 carbon atoms, preferably 4 to 16 carbon atoms, in particular an alicyclic ring, .

As the repeating unit b, a repeating unit (hereinafter also referred to as a repeating unit b3) which is changed from hydrophilic to hydrophobic by a dehydration reaction with an acid may be used. When the recurring unit b3 is used, the resist material of the present invention can be used as a negative resist material for obtaining a negative pattern by alkali development.

Examples of the monomer giving the repeating unit b3 include, but are not limited to, the following. In the following formula, R ⁹ represents a hydrogen atom or a methyl group.

The polymer A may further contain at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether group, an ester group, a sulfonate group, (Hereinafter, also referred to as a repeating unit c) comprising a bonding group selected from the group consisting of -O- (= O) -G- (G is -S- or -NH-). Examples of the monomer giving the repeating unit c include, but are not limited to, the following.

In the case of a monomer containing a hydroxy group, the hydroxy group may be replaced with an acetal group which is easily deprotected by an acid such as an ethoxyethoxy group during the polymerization, deprotected by a weak acid and water after polymerization, And the alkali hydrolysis may be carried out after the polymerization by replacing the alkali by hydrolysis.

The polymer A may further contain a repeating unit derived from a sulfonium salt represented by the following formulas (d1) to (d3) (hereinafter referred to as repeating units d1 to d3, respectively).

In the formulas, R ²⁰ , R ²⁴ and R ²⁸ each independently represent a hydrogen atom or a methyl group. R ²¹ represents a single bond, a phenylene group, -OR ^A -, or -C (= O) -Y ⁰ -R ^A -, Y ⁰ represents -O- or -NH-, R ^A represents a carbonyl group, an ester Branched or cyclic alkylene group of 1 to 6 carbon atoms which may contain one or more groups selected from the group consisting of a hydrogen atom, an ether group or a hydroxy group, or a linear, branched or cyclic alkenylene group having 2 to 6 carbon atoms or a phenylene group. R ²² , R ²³ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁹ , R ³⁰ and R ³¹ each independently represents a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms which may contain a carbonyl group, an ester group or an ether group, A gaseous or cyclic alkyl group, or an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a mercaptophenyl group. Z ¹ represents a straight-chain, branched or cyclic alkylene group having 1 to 12 carbon atoms which may contain a single bond or an ether group, an ester group or a lactone ring, or a straight, branched or cyclic An alkenylene group, or an arylene group having 6 to 10 carbon atoms. Z ² is a single bond, methylene group, an ethylene group, a phenylene group, a fluorinated phenyl group, a -OR ³² -, or ^{-C (= O) -Z 3 -R} 32 - represents the, Z ³ is -O- or - NH-, R ³² represents a linear, branched or cyclic alkylene or alkenylene group having 1 to 12 carbon atoms which may contain a carbonyl group, an ester group, an ether group or a hydroxy group, or a phenylene group. M ^- represents an unconjugated counter ion. d1 to d3 represent positive numbers satisfying 0? d1? 0.5, 0? d2? 0.5, 0? d3? 0.5, and 0 <d1 + d2 + d3?

By bonding an acid generator to the polymer main chain, it is possible to reduce the acid diffusion and prevent degradation of resolution due to clouding of acid diffusion. In addition, the edge roughness (LER, LWR) is improved by uniformly dispersing the acid generator.

Examples of the non-nucleophilic counter ion represented by M ^- include halide ions such as chloride ion and bromide ion; Fluoroalkylsulfonates such as triflate, 1,1,1-trifluoroethanesulfonate and nonafluorobutanesulfonate; Arylsulfonates such as tosylate, benzenesulfonate, 4-fluorobenzenesulfonate, and 1,2,3,4,5-pentafluorobenzenesulfonate; Alkyl sulphonates such as mesylate and butane sulphonate; Imidic acid such as bis (trifluoromethylsulfonyl) imide, bis (perfluoroethylsulfonyl) imide and bis (perfluorobutylsulfonyl) imide; Tris (trifluoromethylsulfonyl) methide, and tris (perfluoroethylsulfonyl) methide.

Further, as the non-nucleophilic counter ion represented by M &lt; ^{- &} gt ;, a sulfonate in which the alpha -position is fluorine-substituted and represented by the following formula (K-1), the alpha and beta positions represented by the following formula (K- Substituted sulfonate.

In formula (K-1), R ⁴¹ represents a hydrogen atom, a straight chain, branched or cyclic alkyl group of 1 to 20 carbon atoms, an alkenyl group of 2 to 20 carbon atoms, or an aryl group of 6 to 20 carbon atoms, An ester group, a carbonyl group, a lactone ring, or a fluorine atom.

In the formula (K-2), R ⁴² represents a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, a linear, branched or cyclic acyl group having 2 to 30 carbon atoms, An aryl group having 6 to 20 carbon atoms, or an aryloxy group having 6 to 20 carbon atoms, and may contain an ether group, an ester group, a carbonyl group, or a lactone ring.

When a polymer containing at least one repeating unit selected from the repeating units d1 to d3 is used, the mixing of the photoacid generator to be described later can be omitted.

The polymer A may further contain repeating units represented by the following formulas (e1) to (e5) (hereinafter also referred to as repeating units e1 to e5).

R ¹¹⁰ to R ¹¹⁴ each independently represent a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkyl group having 1 to 30 carbon atoms in which a part or all of the hydrogen atoms bonded to the carbon atom are substituted with a halogen atom, a hydroxy group, An acyl group having 2 to 30 carbon atoms, an alkoxycarbonyl group having 2 to 30 carbon atoms, an aryl group having 6 to 10 carbon atoms, a halogen atom, or a 1,1,1,3,3,3-hexafluoro-2- Propanol group. X ⁰ represents a methylene group, an ether group, or a sulfide group.

The polymer A may further contain a repeating unit f derived from styrene, vinyl naphthalene, vinyl anthracene, vinyl pyrene, methylene indane or the like.

As a method for synthesizing the polymer A, for example, there can be mentioned a method of adding a desired monomer among the monomers imparting the repeating units a to f to a radical polymerization initiator in an organic solvent and carrying out thermal polymerization.

Examples of the organic solvent used in the polymerization include toluene, benzene, tetrahydrofuran, diethyl ether, dioxane, cyclohexane, cyclopentane, methyl ethyl ketone, and γ-butyrolactone. Examples of the polymerization initiator include azo compounds such as 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis (2,4-dimethylvaleronitrile), dimethyl-2,2- azobis Benzoyl peroxide, lauroyl peroxide, and the like. The reaction temperature is preferably 50 to 80 캜, and the reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours.

In the case of synthesizing a polymer containing a repeating unit derived from hydroxystyrene or hydroxyvinylnaphthalene, acetoxystyrene or acetoxyvinylnaphthalene is used instead of hydroxystyrene or hydroxyvinylnaphthalene, and after the polymerization, an alkali The acetoxy group may be deprotected by hydrolysis to give a hydroxystyrene unit or a hydroxyvinyl naphthalene unit. As the base in the alkali hydrolysis, ammonia water, triethylamine and the like can be used. The reaction temperature is preferably -20 to 100 占 폚, more preferably 0 to 60 占 폚, and the reaction time is preferably 0.2 to 100 hours, more preferably 0.5 to 20 hours.

In the polymer A, the ratio of the repeating units a and b is 0 <a <1.0, 0 <b <1.0, 0.1≤a + b≤1.0. In the case where the repeating unit b is the repeating unit b1 or b2, 0 <a <1.0, 0 b1 <1.0, 0 b2 <1.0, 0 <b1 + b2 <1.0, 0.1≤a + b1 + b2≤1.0 to be. When the repeating unit b is the repeating unit b3, 0 < a < 1.0, 0 < b3 < 1.0 and 0.1 a + b3 &amp;

The ratio of the repeating unit c is 0? C? 0.9, but preferably 0? C? 0.9 and 0.2? A + b + c? 1.0 when the repeating unit c is contained. When the repeating unit b is the repeating unit b1 or b2, it is more preferably 0.02? A? 0.8, 0? B1? 0.8, 0? B2? 0.8, 0.1? B1 + b2? 0.8, 0.1? C? , More preferably 0.05? A? 0.75, 0 b1? 0.7, 0 b2? 0.7, 0.1 b1 + b2? 0.75, 0.15 c? 0.85, particularly preferably 0.07 a? 0.7, 0.65, 0? B2? 0.65, 0.1? B1 + b2? 0.7, and 0.2? C? In this case, 0.2? A + b1 + b2 + c? 1.0, more preferably 0.3? A + b1 + b2 + c? 1.0, further preferably 0.4? A + b1 + b2 + c? 1.0. More preferably 0.05? A? 0.75, 0.1? B3? 0.75, 0.15? B3? 0.88, ? C? 0.85, particularly preferably 0.07? A? 0.7, 0.1? B3? 0.7, and 0.2? C? In this case, 0.2? A + b3 + c? 1.0, more preferably 0.3? A + b3 + c? 1.0, further preferably 0.4? A + b3 + c? 1.0.

D1 + d2 + d3? 0.5. When the repeating units d1 to d3 include the repeating units d1 to d3, the ratio of the repeating units d1 to d3 is 0 < d1 + d2 + d3? 0.5. In this case, preferably 0? D1? 0.4, 0? D2? 0.4, 0? D3? 0.4, 0 <d1 + d2 + d3? 0.4, more preferably 0? D1? 0.3, 0? D3? 0.3, 0 <d1 + d2 + d3? 0.3, more preferably 0? D1? 0.2, 0? D2? 0.2, 0? D3? 0.2, 0 <d1 + d2 + d3? D2 + d3? 1.0, and particularly preferably 0.4? A + b1 + b2 + c + d1 + d2 + d3? 1.0, where 0.2? A + b1 + b2 + c + d1 + d2 +

Also, the ratio of the repeating units e1 to e5 is 0? E1? 0.5, 0? E2? 0.5, 0? E3? 0.5, 0? E4? 0.5, 0? E5? 0.5, 0? E1 + e2 + + e5? 0.5, and when the repeating units include the repeating units e1 to e5, 0 <e1 + e2 + e3 + e4 + e5? In this case, preferably 0? E1? 0.4, 0? E2? 0.4, 0? E3? 0.4, 0? E4? 0.4, 0? E5? 0.4, 0 <e1 + e2 + e3 + e4 + e5? 0.4, More preferably, 0? E1? 0.3, 0? E2? 0.3, 0? E3? 0.3, 0? E4? 0.3, 0? E5? 0.3, 0 <e1 + e2 + e3 + e4 + e5?

The ratio of the repeating unit f is 0? F? 0.5, preferably 0? F? 0.4, and more preferably 0? F? 0.3.

It is also preferable that a + b + c + d1 + d2 + d3 + e1 + e2 + e3 + e4 + e5 + f =

The polymer A has a weight average molecular weight (Mw) of 1,000 to 500,000, preferably 2,000 to 30,000. When the Mw is 1,000 or more, the resist material has excellent heat resistance. When the Mw is 500,000 or less, the alkaline solubility is good, and there is no possibility of the footing phenomenon occurring after pattern formation. Mw is a polystyrene reduced value measured by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

In the polymer A, when the molecular weight distribution (Mw / Mn) of the multicomponent copolymer is large, since a polymer having a low molecular weight or a high molecular weight is present, foreign matter can be seen on the pattern, do. Therefore, in order to obtain a resist material suitably used for a fine pattern size, the molecular weight distribution of the polymer A used is 1.0 to 2.0, particularly 1.0 to 1.5 It is preferable to have narrow dispersion.

In the resist composition of the present invention, the base resin may be a mixture of two or more kinds of polymers including one type of polymer A, a composition ratio, a molecular weight distribution, and a molecular weight, Polymer B may be blended.

[Acid generator]

The resist material of the present invention may contain an acid generator to function as a chemically amplified resist material. Examples of the acid generator include a compound (photo-acid generator) that generates an acid in response to an actinic ray or radiation.

The photoacid generator may be any compound that generates an acid upon irradiation with high energy radiation. Suitable photoacid generators include sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate acid generators, and the like. Specific examples of such photoacid generators include those described in paragraphs [0122] to [0142] of Japanese Patent Application Laid-Open No. 2008-111103.

As the photoacid generator, those represented by the following formula (1) can also be suitably used.

In the formula (1), R ¹⁰¹ , R ¹⁰² and R ¹⁰³ each independently represent a linear, branched or cyclic monovalent hydrocarbon group of 1 to 20 carbon atoms which may contain a hetero atom. Two or more of R ¹⁰¹ , R ¹⁰² and R ¹⁰³ may be bonded to each other to form a ring together with the sulfur atom to which they are bonded.

In the formula (1), X ^- represents an anion selected from the following formulas (1A) to (1D).

In the formula (1A), R ^fa represents a straight, branched or cyclic monovalent hydrocarbon group of 1 to 40 carbon atoms which may contain a fluorine atom or a hetero atom.

The anion represented by the formula (1A) is preferably represented by the following formula (1A ').

In the formula (1A '), R ¹⁰⁴ represents a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R ¹⁰⁵ represents a linear, branched or cyclic monovalent hydrocarbon group of 1 to 38 carbon atoms which may contain a hetero atom. The hetero atom is preferably an oxygen atom, a nitrogen atom, a sulfur atom or a halogen atom, and more preferably an oxygen atom. The monovalent hydrocarbon group preferably has 6 to 30 carbon atoms, in particular, from the viewpoint of obtaining a high resolution in forming a fine pattern. Examples of the monovalent hydrocarbon group include monovalent hydrocarbon groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an s-butyl group, a t-butyl group, a pentyl group, a neopentyl group, a cyclopentyl group, An isoamyl group, a 1-adamantyl group, a 1-adamantyl group, a 1-adamantyl group, a 2-ethylhexyl group, An allyl group, a benzyl group, a diphenylsulfonyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group, (2-methoxyethoxy) methyl group, an acetoxymethyl group, a 2-carboxy-1-cyclohexyl group, a 2-methoxyethoxy group, a 2- A 2-oxopropyl group, a 4-oxo-1-adamantyl group, and a 3-oxocyclohexyl group. . A part of the hydrogen atoms of these groups may be substituted with a heteroatom-containing group such as an oxygen atom, a sulfur atom, a nitrogen atom or a halogen atom, or an oxygen atom, sulfur atom, nitrogen An ether group, an ester group, a sulfonate group, a carbonate group, a lactone ring, a sultone ring, a carboxylic acid anhydride, a haloalkyl group, a hydroxyl group, And the like.

With respect to the synthesis of a sulfonium salt containing an anion represented by the formula (1A '), JP-A 2007-145797, JP-A 2008-106045, JP-A 2009-7327, 2009-258695 and the like. Sulfonium salts described in JP-A-2010-215608, JP-A-2012-41320, JP-A-2012-106986 and JP-A-2012-153644 are also suitably used.

Examples of the sulfonium salt containing an anion represented by the formula (1A) include, but are not limited to, the following sulfonium salts. In the following formulas, Ac represents an acetyl group and Ph represents a phenyl group.

In formula (1B), R ^fb1 and R ^fb2 each independently represent a straight, branched or cyclic monovalent hydrocarbon group of 1 to 40 carbon atoms which may contain a fluorine atom or a hetero atom. Examples of the monovalent hydrocarbon group include the same monovalent hydrocarbon groups as those described above in the description of R ¹⁰⁵ . R ^fb1 and R ^fb2 are preferably a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. In addition, R ^fb1 and ^fb2 R are coupled together by group to which they are bonded ^{_{(-CF 2 -SO 2 -N - -SO}} 2 -CF 2 -) may be formed with a ring, in which case, R and R ^{fb1 The} group obtained by mutual bonding of ^fb2 is preferably a fluorinated ethylene group or a fluorinated propylene group.

In formula (1C), R ^fc1 , R ^fc2 and R ^fc3 each independently represent a straight, branched or cyclic monovalent hydrocarbon group of 1 to 40 carbon atoms which may contain a fluorine atom or a hetero atom. Examples of the monovalent hydrocarbon group include those exemplified in the description of R ¹⁰⁵ above. R ^fc1 , R ^fc2 and R ^fc3 are preferably a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. R ^fc1 and R ^fc2 may form a ring together with the group (-CF ₂ -SO ₂ -C ^- -SO ₂ -CF ₂ -) to which they are bonded to form a ring. In this case, R ^fc1 and R ^The group obtained by mutual bonding of ^fc2 is preferably a fluorinated ethylene group or a fluorinated propylene group.

In the formula (1D), R ^fd represents a linear, branched or cyclic monovalent hydrocarbon group of 1 to 40 carbon atoms which may contain a hetero atom. Examples of the monovalent hydrocarbon group include the same monovalent hydrocarbon groups as those described above in the description of R ¹⁰⁵ .

The synthesis of a sulfonium salt containing an anion represented by the formula (1D) is described in detail in JP-A-2010-215608 and JP-A-2014-133723.

Examples of the sulfonium salt containing an anion represented by the formula (1D) include, but are not limited to, the following sulfonium salts. In the following formula, Ph represents a phenyl group.

The photoacid generator containing an anion represented by the formula (1D) does not have fluorine at the? -Position of the sulfo group but has two trifluoromethyl groups at the? -Position, It has sufficient acidity to cleave the labile group. Therefore, it can be used as a photoacid generator.

As the photoacid generator, those represented by the following formula (2) can also be suitably used.

In formula (2), R ²⁰¹ and R ²⁰² each independently represents a linear, branched or cyclic monovalent hydrocarbon group of 1 to 30 carbon atoms which may contain a hetero atom. R ²⁰³ represents a linear, branched or cyclic divalent hydrocarbon group of 1 to 30 carbon atoms which may contain a hetero atom. Two or more of R ²⁰¹ , R ²⁰² and R ²⁰³ may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. L ^A represents a straight-chain, branched or cyclic divalent hydrocarbon group of 1 to 20 carbon atoms which may contain a single bond, an ether group or a hetero atom. X ^A , X ^B , X ^C and X ^D each independently represent a hydrogen atom, a fluorine atom or a trifluoromethyl group. Provided that at least one of X ^A , X ^B , X ^C and X ^D represents a substituent other than a hydrogen atom. k represents an integer of 0 to 3;

Examples of the monovalent hydrocarbon group include monovalent hydrocarbon groups such as methyl, ethyl, propyl, isopropyl, n-butyl, s-butyl, A cyclohexyl group, a cyclohexyl group, a cyclohexyl group, a cyclopentyl group, a cyclopentyl group, a cyclohexylmethyl group, a cyclohexylethyl group, a cyclohexyl group, a cyclohexyl group, a cyclohexyl group, Butyl group, norbornyl group, oxanorbornyl group, tricyclo [5.2.1.0 ^2,6 ] decanyl group, adamantyl group, phenyl group, naphthyl group and anthracenyl group. Some of the hydrogen atoms of these groups may be substituted with a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom or a halogen atom, or a part of carbon atoms may be replaced with a hetero atom such as an oxygen atom, a sulfur atom, And may contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonic acid ester bond, a carbonate bond, a lactone ring, a lactone ring, a carboxylic acid anhydride, a haloalkyl group and the like.

Examples of the divalent hydrocarbon group include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, -1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane- Diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane- A straight chain alkanediyl group such as a 17-diyl group; A saturated cyclic divalent hydrocarbon group such as a cyclopentanediyl group, a cyclopentanediyl group, a cyclohexanediyl group, a norbornanediyl group, and an adamantanediyl group; And unsaturated cyclic divalent hydrocarbon groups such as a phenylene group and a naphthylene group. A part of the hydrogen atoms of these groups may be substituted with an alkyl group such as a methyl group, an ethyl group, a propyl group, an n-butyl group or a t-butyl group. A part of the hydrogen atoms of these groups may be substituted with a heteroatom-containing group such as an oxygen atom, a sulfur atom, a nitrogen atom or a halogen atom, or an oxygen atom, sulfur atom, nitrogen An ether group, an ester group, a sulfonate group, a carbonate group, a lactone ring, a sultone ring, a carboxylic acid anhydride, a haloalkyl group, a hydroxyl group, And the like. The hetero atom is preferably an oxygen atom.

The photoacid generator represented by the formula (2) is preferably represented by the following formula (2 ').

In formula (2 '), L ^A is the same as above. L ^B represents a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R ³⁰¹ , R ³⁰² and R ³⁰³ each independently represents a hydrogen atom or a straight, branched or cyclic monovalent hydrocarbon group of 1 to 20 carbon atoms which may contain a hetero atom. Examples of the monovalent hydrocarbon group include the same monovalent hydrocarbon groups as those described above in the description of R ¹⁰⁵ . x and y each independently represent an integer of 0 to 5, and z represents an integer of 0 to 4.

Examples of the photoacid generator represented by the formula (2) include, but are not limited to, the following compounds. In the following formula, L ^B is as defined above, and Me represents a methyl group.

Among the above-mentioned photoacid generators, those containing anions represented by the formula (1A ') or (1D) are particularly preferable because of their small acid diffusion and excellent solubility in a resist solvent. Including the anion represented by the formula (2 ') is particularly preferable because the acid diffusion is very small.

The blending amount of the acid generator is preferably 0.01 to 100 parts by mass, more preferably 0.1 to 80 parts by mass, per 100 parts by mass of the base resin. The acid generators may be used singly or in combination of two or more.

[Organic solvents]

The resist material of the present invention may contain an organic solvent. Examples of the organic solvent include ketones such as cyclohexanone and methyl n-pentyl ketone described in paragraphs [0144] to [0145] of JP-A No. 2008-111103; Alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol and 1-ethoxy-2-propanol; Ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether and diethylene glycol dimethyl ether; Propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, t-butyl acetate, Esters such as glycol mono-t-butyl ether acetate; and lactones such as? -butyrolactone. These solvents may be used singly or in combination of two or more.

The blending amount of the organic solvent is preferably 50 to 10,000 parts by mass, more preferably 100 to 5,000 parts by mass per 100 parts by mass of the base resin.

[Other components]

The resist composition of the present invention may further contain a basic compound, a solubilizer, a surfactant, acetylenic alcohols, and the like.

By mixing a basic compound with a resist material, for example, the diffusion rate of acid in the resist film can be suppressed, and the resolution can be further improved. Examples of the basic compound include those described in paragraphs [0146] to [0164] of JP-A No. 2008-111103. Of these, amine compounds including primary, secondary, and tertiary amine compounds, particularly, hydroxyl groups, ether groups, ester groups, lactone rings, cyano groups, sulfonate ester groups and the like are preferable. The blending amount of the basic compound is preferably 0 to 100 parts by mass, more preferably 0.001 to 50 parts by mass, per 100 parts by mass of the base resin.

By adding a surfactant to the resist material, the applicability of the resist material can be further improved or controlled. Examples of the surfactant include those described in paragraphs [0165] to [0166] of JP-A No. 2008-111103. The blending amount of the surfactant is preferably 0 to 10 parts by mass, more preferably 0.0001 to 5 parts by mass, per 100 parts by mass of the base resin.

By mixing a dissolution agent in a resist material, the difference in dissolution rate between the exposed portion and the unexposed portion can be further increased, and the resolution can be further improved. Examples of the dissolver agent include those described in paragraphs [0155] to [0178] of JP-A-2008-122932. The blending amount of the dissolving agent y is preferably 0 to 50 parts by mass, more preferably 0 to 40 parts by mass with respect to 100 parts by mass of the base resin.

Examples of the acetylene alcohols include those described in paragraphs [0179] to [0182]. The blending amount of acetylene alcohols is preferably 0 to 2% by mass, more preferably 0.02 to 1% by mass in the resist material.

 A polymer type quencher described in JP-A-2008-239918 may be incorporated in the resist material of the present invention. This can increase the sphere formation of the resist after the pattern by orienting it on the surface of the resist after coating. The polymer-type retainer also has an effect of preventing film reduction of the pattern and rounding of the pattern top when a protective film is applied on the resist. When the above-mentioned polymer type quencher is included, the amount thereof may be arbitrarily set within a range that does not impair the effect of the present invention.

In the resist material of the present invention, a sulfonic acid in which the? -Position is not fluorinated, represented by the following formula (3), or an onium salt of a carboxylic acid represented by the following formula (4) may be blended as a quencher.

(Wherein R ¹⁵¹ , R ¹⁵² and R ¹⁵³ are each independently a hydrogen atom, a halogen atom other than a fluorine atom, or a linear, branched or cyclic monovalent hydrocarbon group of 1 to 40 carbon atoms which may contain a heteroatom represents Further, R ^151, R ¹⁵² and R ¹⁵³ are any two or more of, and may be mutually bonded to form a ring with the carbon atoms to which they are attached. R ¹⁵⁴ which may contain a hetero atom having a carbon number of 1 to 40 Branched or cyclic monovalent hydrocarbon group represented by the formula: M ⁺ represents an onium cation.)

The onium salt of a sulfonic acid in which the? position is not fluorinated is described in detail in JP-A-2008-158339. Examples of the photoacid generator that generates a sulfonic acid in which the? position is not fluorinated include compounds described in paragraphs [0019] to [0036] of JP-A No. 2010-155824, The compounds described in [0047] to [0082] can be mentioned. The onium salt of a carboxylic acid is described in detail in Japanese Patent No. 3991462.

The anion in the formula (3) or (4) is a conjugate base of a weak acid. The weak acid as used herein refers to an acidity which can not deprotect an acid labile group of an acid labile group-containing unit used in a base resin. The onium salt represented by the formula (3) or the formula (4) functions as a quencher when it is used in combination with an onium salt photoacid generator having a strong acid conjugate base such as a sulfonic acid fluorinated at the? Position as a counter anion.

That is, when an onium salt generating a strong acid such as a sulfonic acid fluorinated at the? Position is mixed with an onium salt generating a weak acid such as a sulfonic acid or a carboxylic acid which is not fluorine-substituted, When a strong acid generated from a zeolite collides with an onium salt having an unreacted weak acid anion, it releases a weak acid by salt exchange and generates an onium salt having a strong acid anion. In this process, since the strong acid is exchanged with a weak acid having a lower catalytic activity, it is apparent that the acid can be inactivated and the acid diffusion can be controlled.

Particularly, the sulfonium salt and the iodonium salt of the sulfonic acid and the carboxylic acid in which the? -Position is not fluorinated are photodegradable, so that the quenching ability of the portion having a high light intensity is lowered and the sulfonic acid, The concentration of imidic acid or methidic acid increases. This makes it possible to form a pattern with good dimensional control, in which the contrast of the exposed portion is improved and the depth of focus (DOF) is further improved.

In the case where the photoacid generator that generates strong acid is an onium salt, the strong acid generated by the high energy beam irradiation can be replaced with the weak acid as described above. However, the weak acid generated by the high energy beam irradiation generates unreacted strong acid It is considered that the salt exchange can not be performed by colliding with the onium salt. This is due to the phenomenon that the onium cation is liable to form an ion pair with an anion of stronger acid.

When the acid labile group is a particularly sensitive acetal to the acid, the acid for releasing the protecting group may not necessarily be a sulfonic acid, imidic acid or methidic acid fluorinated at the? Position, or a sulfonic acid in which the? There is a case where progress is made. In this case, since the onium salt of the sulfonic acid can not be used as the quencher in this case, it is preferable to use the onium salt of the carboxylic acid alone.

As the onium salt of the sulfonic acid in which the α-position is not fluorinated and the onium salt of the carboxylic acid, an onium salt of the sulfonic acid represented by the following formula (3 ') and a carboxylic acid represented by the following formula (4' Is preferred.

In the formula, R ²⁵¹ , R ²⁵² and R ²⁵³ each independently represent a linear, branched or cyclic monovalent hydrocarbon group of 1 to 20 carbon atoms which may contain a hetero atom. Two or more of R ²⁵¹ , R ²⁵² and R ²⁵³ may bond together to form a ring together with the atoms to which they are bonded and the atoms therebetween. R ²⁵⁴ represents a linear, branched or cyclic monovalent hydrocarbon group of 1 to 40 carbon atoms which may contain a hetero atom. R ²⁵⁵ and R ²⁵⁶ each independently represent a hydrogen atom or a trifluoromethyl group. R ²⁵⁷ and R ²⁵⁸ each independently represent a hydrogen atom, a fluorine atom or a trifluoromethyl group. R ²⁵⁹ represents a linear, branched or cyclic monovalent hydrocarbon group of 1 to 35 carbon atoms which may contain a hydrogen atom, a hydroxyl group or a hetero atom, or a substituted or unsubstituted aryl group of 6 to 30 carbon atoms. r represents an integer of 1 to 3; z ¹ , z ² and z ³ each independently represent an integer of 0 to 5;

When such an onium salt is used as a quencher, it may be used singly or in combination of two or more species. The blending amount is preferably 0 to 50 parts by mass, more preferably 0.001 to 50 parts by mass, and even more preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the base resin. By incorporating such a quencher in the above range, adjustment of the resist sensitivity can be facilitated. In addition, the diffusion rate of the acid in the resist film is suppressed to improve the resolution, suppress the change in sensitivity after exposure, , The exposure margin, the pattern profile, and the like can be improved. In addition, the substrate adhesion can be improved by adding such a quencher.

The resist material of the present invention may be blended with a polymer compound (water repellency improving agent) for improving the water repellency of the resist surface after spin coating. The water repellency improving agent can be used for immersion lithography without using a topcoat. As the water repellency improving agent, a polymer compound containing an alkyl fluoride group, a polymer compound containing a 1,1,1,3,3,3-hexafluoro-2-propanol residue of a specific structure, and the like are preferable, 297590, and Japanese Patent Laid-Open Publication No. 2008-111103. The water repellency improving agent needs to be dissolved in an organic solvent developer. The water repellency improving agent having the above-mentioned specific 1,1,1,3,3,3-hexafluoro-2-propanol residue has good solubility in a developing solution. As a water repellency improving agent, a polymer compound in which an amino group or an amine salt is copolymerized as a repeating unit has a high effect of preventing evaporation of an acid in PEB and preventing opening defect in a hole pattern after development. When the water repellency improving agent is contained, the amount thereof is preferably from 0.1 to 20 parts by mass, more preferably from 0.5 to 10 parts by mass, per 100 parts by mass of the base resin of the resist material.

By forming a resist composition by appropriately combining and combining an acid generator, an organic solvent, a solubilizer, a basic compound, a surfactant, and the like with the base resin containing the polymer A in accordance with the object, in the exposure part, The dissolution rate for the developing solution is accelerated, so that a highly sensitive resist material can be obtained. The resist material of the present invention has high resolution contrast and resolution of the resulting resist film, has an exposure margin, is excellent in process adaptability, exhibits good pattern shape after exposure, exhibits excellent etching resistance, Can be suppressed, the compact size difference is small, practicality is high from those, and it is very effective as a resist material for a super LSI. Particularly, when a chemically amplified resist material is compounded with an acid generator and uses an acid catalyst reaction, the resist can be made to have a higher sensitivity, and furthermore various characteristics are further improved, which is very useful.

[Pattern formation method]

When a resist material of the present invention, for example, a chemically amplified resist material including a base resin, an acid generator, an organic solvent, and a basic compound is used in the manufacture of various integrated circuits, a known lithography technique can be applied.

For example, the resist material of the present invention can be used as a substrate for producing integrated circuits (Si, SiO ₂ , SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflection film, MoSi ₂ , SiO ₂ or the like) is applied by a suitable coating method such as spin coating, roll coating, flow coating, dip coating, spray coating or doctor coating so as to have a coating film thickness of 0.1 to 2.0 μm. This is prebaked on a hot plate, preferably at 60 to 150 DEG C for 10 seconds to 30 minutes, more preferably at 80 to 120 DEG C for 30 seconds to 20 minutes. A protective film may be formed on the resist film. The protective film is preferably soluble in an alkali developing solution. At the time of development, the protective film is peeled together with the formation of the resist pattern. The protective film has a function of reducing outgas from the resist film, a function as a filter for cutting an out-of-band (OOB) having a wavelength of 140 to 300 nm other than 13.5 nm generated from an EUV laser, It has the function of preventing T-sawing or causing film reduction. Subsequently, a desired pattern is irradiated through a predetermined mask or directly exposed to a light source selected from high energy radiation such as ultraviolet rays, far ultraviolet rays, EUV, EB, X-rays, soft x-rays, excimer lasers, gamma rays, synchrotron radiation, I do. The exposure dose is preferably about 1 to ²⁰⁰ mJ / cm ² , particularly about 10 to 100 mJ / cm ² , or about 0.1 to 100 μC / cm ² , especially 0.5 to 50 μC / cm ² . Then, PEB is preferably performed on a hot plate at 60 to 150 DEG C for 10 seconds to 30 minutes, more preferably at 80 to 120 DEG C for 30 seconds to 20 minutes.

(TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TMAH), tetrabutylammonium hydroxide A dip method, a puddle method, a spray method, or the like using a developer of an aqueous alkali solution such as ammonium hydroxide (TBAH) for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes , When the polymer A contains the repeating units b1 and / or b2, the portion irradiated with the light is dissolved in the developing solution, the portion not irradiated is not dissolved, and the portion of the positive type When the pattern is formed and the polymer A includes the repeating unit b3, a negative pattern is formed on the substrate. In addition, the resist material of the present invention is particularly suitable for fine patterning by EB, EUV, X-ray, soft X-ray,? -Ray and synchrotron radiation even in a high energy beam.

Generally, TEAH, TPAH, TBAH and the like having longer alkyl chains than the widely used TMAH have the effect of reducing the swelling during development and preventing the collapse of the pattern. Japanese Patent No. 3429592 discloses a polymer comprising repeating units containing an alicyclic structure such as adamantane methacrylate and repeating units containing an acid labile group such as t-butyl methacrylate and having no hydrophilic group and having high water repellency An example using TBAH aqueous solution is presented.

As the TMAH developing solution, 2.38% by mass aqueous solution of TMAH is most widely used. This corresponds to 0.26 N, and it is preferable that aqueous solutions such as TEAH, TPAH, and TBAH have the same definition. The masses of TEAH, TPAH and TBAH which are 0.26 N are 3.84 mass%, 5.31 mass% and 6.78 mass%, respectively.

In a pattern of 32 nm or less resolved by EB or EUV, a phenomenon occurs in which lines are twisted, lines are stuck to each other, or a stuck line is collapsed. This is considered to be caused by the swelling of the developing solution and the swelling of the lines. The swelled line is soft as a sponge, including a developing solution, so that it becomes easy to fall down due to the stress of the rinse. A developing solution in which an alkyl chain is elongated has an effect of preventing swelling and preventing pattern collapse.

When the polymer A contains the repeating units b1 and / or b2, a negative pattern can be obtained by organic solvent development. As the developing solution, there can be mentioned 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutylketone, methylcyclohexanone, , Methyl acetophenone, propyl acetate, butyl acetate, isobutyl acetate, pentyl acetate, butenyl acetate, isopentyl acetate, propyl formate, butyl formate, isobutyl formate, pentyl formate, isopentyl formate, methyl valerate, methyl pentenoate , Ethyl crotonate, ethyl crotonate, methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, pentyl lactate, isopentyl lactate, Benzyl benzoate, benzyl benzoate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, phenyl benzoate, phenylacetyl benzoate, benzyl benzoate, Ethyl acetate, 2-phenylethyl acetate and the like. These solvents may be used singly or in combination of two or more kinds.

At the end of development, rinsing is performed. As the rinse solution, a solvent which is mixed with a developing solution and does not dissolve the resist film is preferable. As such a solvent, an alcohol of 3 to 10 carbon atoms, an ether compound of 8 to 12 carbon atoms, an alkane of 6 to 12 carbon atoms, an alkene, an alkyne, and an aromatic solvent are preferably used.

Specific examples of the alcohol having 3 to 10 carbon atoms include n-propyl alcohol, isopropyl alcohol, 1-butyl alcohol, 2-butyl alcohol, isobutyl alcohol, t- 1-butanol, 3-methyl-3-pentanol, cyclopentanol, 1-hexanol, 2-hexanol, Butanol, 3,3-dimethyl-1-butanol, 3,3-dimethyl-2-butanol, 2-ethyl- Pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl- Methyl-1-pentanol, 4-methyl-2-pentanol, 4-methyl-3-pentanol, cyclohexanol and 1-octanol.

Examples of the ether compound having from 8 to 12 carbon atoms include di-n-butyl ether, diisobutyl ether, di-s-butyl ether, di-n-pentyl ether, diisopentyl ether, di- Pentyl ether, di-n-hexyl ether, and the like.

Examples of the alkane having 6 to 12 carbon atoms include hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, Nonan, and the like. Examples of the alkene having 6 to 12 carbon atoms include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, cyclooctene and the like. Examples of the alkyne having 6 to 12 carbon atoms include hexyne, heptyne, octyne and the like.

Examples of aromatic solvents include toluene, xylene, ethylbenzene, isopropylbenzene, t-butylbenzene, and mesitylene.

Example

Hereinafter, the present invention will be described in detail by way of Synthesis Examples, Comparative Synthesis Examples, Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[1] Synthesis of monomers

[Synthesis Example 1] Synthesis of monomer 1

45 g of 2-hydroxy-N-methylsuccinimide and 3.7 g of 4- (dimethylamino) pyridine were dissolved in 500 g of THF, and 92.4 g of methacrylic acid chloride was added dropwise under ice cooling. After stirring at room temperature for 5 hours, water was added to stop the reaction. After the usual post-aqueous treatment, purification was carried out by silica gel column chromatography to obtain 120 g of monomer 1.

[Synthesis Example 2] Synthesis of monomer 2

128 g of monomer 2 was obtained in the same manner as in Synthesis Example 1 except that methacrylic acid chloride was replaced by 128 g of 2-carboxymethyl methacrylate.

[2] Synthesis of polymer

In the following synthesis examples, Mw is measured by polystyrene conversion by gel permeation chromatography (GPC) using THF as a solvent. The monomers 3 to 4 and PAG monomers 1 to 2 used in the following Synthesis Examples are as follows.

[Synthesis Example 3] Synthesis of polymer 1

A 2 L flask was charged with 5.6 g of dodecanyl methacrylate, 1-isopropyl exotetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] methacrylate, 3.9 g of 1-isopropylcyclopentyl methacrylate, 2.2 g of 3-hydroxy-1-adamantyl acid, 5.9 g of monomer 1, 5.9 g of 2-oxo-4,5-dimethyltetrahydrofuran-4-yl methacrylate, and 40 g of THF g. The reaction vessel was cooled to -70 占 폚 in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN as a polymerization initiator was added, the temperature was raised to 60 캜, and the reaction was carried out for 15 hours. The reaction solution was added to 1 L of isopropyl alcohol, and the precipitated white solid was filtered and dried under reduced pressure at 60 캜 to obtain a white polymer (polymer 1).

The obtained polymer was measured by ¹³ C-NMR, ¹ H-NMR and GPC, and the following analysis results were obtained.

Composition ratio (molar ratio)

Methacrylic acid 1-isopropyl exotetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl methacrylate: 1-isopropylcyclopentyl methacrylate: 3-hydroxy-1-adamantyl methacrylate: Monomer 1: 2-oxo-4,5-dimethyltetrahydrofuran-4-yl methacrylate = 0.20: 0.20: 0.10: 0.20: 0.30

Mw = 7,500

Mw / Mn = 1.59

[Synthesis Example 4] Synthesis of polymer 2

In a 2 L flask, 11.7 g of the monomer 3, 2.2 g of 3-hydroxy-1-adamantyl methacrylate, 5.9 g of the monomer 1, 7.2 g of the monomer 4 and 40 g of THF as a solvent were added . The reaction vessel was cooled to -70 占 폚 in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN as a polymerization initiator was added, the temperature was raised to 60 캜, and the reaction was carried out for 15 hours. The reaction solution was added to 1 L of isopropyl alcohol, and the precipitated white solid was filtered and dried under reduced pressure at 60 캜 to obtain a white polymer (polymer 2).

The obtained polymer was measured by ¹³ C-NMR, ¹ H-NMR and GPC, and the following analysis results were obtained.

Composition ratio (molar ratio)

Monomer 3: methacrylic acid 3-hydroxy-1-adamantyl: monomer 1: monomer 4 = 0.35: 0.10: 0.30: 0.25

Mw = 7,500

Mw / Mn = 1.59

[Synthesis Example 5] Synthesis of polymer 3

5.2 g of 1- (adamantan-1-yl) -1-methylethyl methacrylate, 3.1 g of 4- (1-methylcyclopentyloxy) styrene, 8.9 g of Monomer 1, 4.4 g of 4-hydroxyphenyl methacrylate, 11.0 g of PAG monomer 1 and 40 g of THF as a solvent were added. The reaction vessel was cooled to -70 占 폚 in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN as a polymerization initiator was added, the temperature was raised to 60 캜, and the reaction was carried out for 15 hours. The reaction solution was added to 1 L of isopropyl alcohol, and the precipitated white solid was filtered and dried under reduced pressure at 60 캜 to obtain a white polymer (polymer 3).

The obtained polymer was measured by ¹³ C-NMR, ¹ H-NMR and GPC, and the following analysis results were obtained.

Composition ratio (molar ratio)

Methacrylic acid 1- (adamantan-1-yl) -1-methylethyl 4- (1-methylcyclopentyloxy) styrene monomer 1 methacrylic acid 4-hydroxyphenyl PAG monomer 1 0.20: 0.15: 0.30: 0.20: 0.15

Mw = 9,300

Mw / Mn = 1.76

[Synthesis Example 6] Synthesis of polymer 4

In a 2 L flask, 13.7 g of 4-methylcyclohexyloxyphenyl methacrylate, 8.9 g of Monomer 1, 16.0 g of PAG monomer 2 and 40 g of THF as a solvent were added. The reaction vessel was cooled to -70 占 폚 in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN as a polymerization initiator was added, the temperature was raised to 60 캜, and the reaction was carried out for 15 hours. This reaction solution was added to 1 L of isopropyl alcohol, and the precipitated white solid was filtered and dried under reduced pressure at 60 캜 to obtain a white polymer (polymer 4).

The obtained polymer was measured by ¹³ C-NMR, ¹ H-NMR and GPC, and the following analysis results were obtained.

Composition ratio (molar ratio)

Methacrylic acid 4-methylcyclohexyloxyphenyl: monomer 1: PAG monomer 2 = 0.50: 0.30: 0.20

Mw = 8,300

Mw / Mn = 1.74

[Synthesis Example 7] Synthesis of polymer 5

In a 2 L flask, 5.6 g of 1-isopropyl exotetracyclo [4.4.0.1 ^2,5 .1 ^{7! 10} ] dodecanyl methacrylate, 3.9 g of 1-isopropylcyclopentyl methacrylate, 2.2 g of acid 3-hydroxy-1-adamantyl, 12.9 g of monomer 2, and 40 g of THF as a solvent were added. The reaction vessel was cooled to -70 占 폚 in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN as a polymerization initiator was added, the temperature was raised to 60 캜, and the reaction was carried out for 15 hours. The reaction solution was added to 1 L of isopropyl alcohol, and the precipitated white solid was filtered and dried under reduced pressure at 60 캜 to obtain a white polymer (polymer 5).

The obtained polymer was measured by ¹³ C-NMR, ¹ H-NMR and GPC, and the following analysis results were obtained.

Composition ratio (molar ratio)

Methacrylic acid 1-isopropyl exotetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl methacrylate: 1-isopropylcyclopentyl methacrylate: 3-hydroxy-1-adamantyl methacrylate: Monomer 2 = 0.20: 0.20: 0.10: 0.50

Mw = 8,500

Mw / Mn = 1.95

[Comparative Synthesis Example 1]

Comparative polymer 1 was synthesized in the same manner as in Synthesis Example 3 except that monomer 1 was not used.

Composition ratio (molar ratio)

Methacrylic acid 1-isopropyl exotetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl methacrylate: 1-isopropylcyclopentyl methacrylate: 3-hydroxy-1-adamantyl methacrylate: 2-oxo-4,5-dimethyltetrahydrofuran-4-yl methacrylate 0.20: 0.20: 0.10: 0.50

Mw = 8,900

Mw / Mn = 1.71

[Comparative Synthesis Example 2] Synthesis of Comparative Polymer 2

Comparative polymer 2 was synthesized in the same manner as in Synthesis Example 4 except that 2-oxo-4,5-dimethyltetrahydrofuran methacrylate was used instead of the monomer 1.

Composition ratio (molar ratio)

Monomer 3: methacrylic acid 3-hydroxy-1-adamantyl methacrylic acid 2-oxo-4,5-dimethyltetrahydrofuran: monomer 4 = 0.35: 0.10: 0.30: 0.25

Mw = 7,700

Mw / Mn = 1.51

[Comparative Synthesis Example 3]

Comparative polymer 3 was synthesized in the same manner as in Synthesis Example 5 except that 2-oxotetrahydrofuran-3-yl methacrylate was used instead of the monomer 1.

Composition ratio (molar ratio)

Methacrylic acid 1- (adamantan-1-yl) -1-methylethyl 4- (1-methylcyclopentyloxy) styrene methacrylate 2-oxotetrahydrofuran- - hydroxyphenyl: PAG monomer 1 = 0.20: 0.15: 0.30: 0.20: 0.15

Mw = 9,100

Mw / Mn = 1.78

[3] ArF exposure patterning evaluation

[Examples 1-1 to 1-3, Comparative Examples 1-1 to 1-2]

A solution obtained by dissolving each component in the composition shown in Table 1 was filtered through a filter having a size of 0.2 mu m into a solvent in which 100 ppm of a surfactant FC-4430 manufactured by Sumitomo 3M Ltd. was dissolved to obtain a positive resist material (R- R-5) was prepared.

The respective compositions in Table 1 are as follows.

Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

           GBL (gamma -butyrolactone)

Acid generator: PAG1

Kenter: The Keeper 1

Water repellent polymer 1: Mw = 12,800, Mw / Mn = 1.71

The prepared resist materials (R-1 to R-5) were spin-coated on a silicon wafer with a spin-on-carbon film ODL-101 (content of carbon is 80 mass%) manufactured by Shin-Etsu Chemical Co., Coated on a substrate for a tri-layer process in which an on-hard mask SHB-A940 (content of silicon of 43 mass%) was formed to a film thickness of 35 nm and baked at 80 DEG C for 60 seconds using a hot plate, A resist film of 80 nm was formed.

This was immersed in an ArF excimer laser immersion scanner (manufactured by Nikon Corporation, NSR-610C, NA 1.30, sigma 0.98 / 0.78, cross pores opening 20 degrees, azimuthally polarized illumination, 6% halftone phase shift mask, And a line width of 30 nm) was used to perform exposure while changing the exposure amount. After the exposure, the film was subjected to PEB for 60 seconds at the temperature shown in Table 2, and the developing solution described in Table 2 Was discharged for 3 seconds while rotating at 30 rpm, and then a stop puddle development was performed for 27 seconds and spin-dried to obtain a negative pattern.

Image of solvent phenomenon Dimensions of 50 reversed hole patterns were measured with TDSEM (CG-4000 manufactured by Hitachi High-Technologies Co., Ltd.), and the dimensional deviation of 3σ was obtained. The cross-sectional shape of the hole pattern was observed with an electron microscope S-4300 manufactured by Hitachi High-Technologies Corporation. The results are shown in Table 2.

From the results shown in Table 2, the resist material of the present invention was excellent in dimensional uniformity of the pattern.

[4] EB imaging evaluation

[Examples 2-1 to 2-2, Comparative Example 2-1]

A solution obtained by dissolving each component in the composition shown in Table 3 was filtered with a filter having a size of 0.2 mu m into a solvent in which 100 ppm of a surfactant FC-4430 manufactured by Sumitomo 3M Co., Ltd. was dissolved to obtain a positive resist material (R- R-8) was prepared.

The respective compositions in Table 3 are as follows.

Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

           PGME (propylene glycol monomethyl ether)

           CyH (cyclohexanone)

Basic compound: amine 1

A clean track mark 5 (Mark 5, manufactured by Tokyo Electron Co., Ltd.) was applied onto a silicon substrate obtained by subjecting the prepared resist materials (R-6 to R-8) to hexamethyldisilazane (HMDS) And prebaked on a hot plate at 110 DEG C for 60 seconds to prepare a resist film having a thickness of 100 nm. In this, HL-800D (manufactured by Hitachi, Ltd.) was used to draw in a vacuum chamber at an HV voltage of 50 kV.

Immediately after the drawing, PEB was carried out on the hot plate at a temperature shown in Table 4 for 60 seconds using Clean Track Mark 5 immediately, and a puddle development was performed for 30 seconds with a 2.38% by mass aqueous solution of TMAH to obtain a positive pattern.

The obtained resist pattern was evaluated as follows.

The edge roughness (LWR) of 100 nm LS was measured by SEM with the minimum dimension as the resolution at the exposure amount for resolving 100 nm line and space at 1: 1. The results are shown in Table 4.

Claims (12)

A base resin comprising a polymer having a repeating unit represented by the following formula (a) and a repeating unit containing a group whose polarity is changed by an acid, and having a weight average molecular weight of 1,000 to 500,000,
Resist material in which the repeating unit containing a group whose polarity is changed by an acid is a repeating unit which is changed from hydrophilic to hydrophobic by a dehydration reaction with an acid:

(Wherein, R ¹ represents a hydrogen atom or a methyl group. R ² represents an alkyl group of a straight chain of the hydrogen atoms, having 1 to 8 carbon atoms, branched or cyclic alkyl group having a carbon number of 3 to 8, 2 to 6 carbon atoms in a straight chain O A branched or cyclic acyl group having 4 to 6 carbon atoms, a straight-chain alkoxycarbonyl group having 2 to 6 carbon atoms, a branched or cyclic alkoxycarbonyl group having 4 to 6 carbon atoms, X ¹ is a single bond, , A naphthylene group, or a linking group having 1 to 12 carbon atoms including an ester group, an ether group or a lactone ring, and a represents a positive integer satisfying 0 <a <1.0. delete delete delete delete The resist composition according to claim 1, wherein the repeating unit containing a group whose polarity is changed by an acid is derived from a monomer represented by the following formula:

(In the formula, R ⁹ represents a hydrogen atom or a methyl group.) The polymer according to claim 1, wherein the polymer is at least one selected from the group consisting of a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether group, an ester group, a sulfonate group, And -OC (= O) -G- (wherein G is -S- or -NH-). The resist composition according to claim 1, wherein the polymer further comprises at least one repeating unit selected from the following formulas (d1) to (d3):

(Wherein, R ^20, R ²⁴ and R ²⁸ each independently represent a hydrogen atom or a methyl group, R ²¹ represents a single bond, phenylene group, -OR ^A -., Or ^{-C (= O) -Y 0 -R} A - , Y ⁰ represents -O- or -NH-, R ^A represents a straight chain alkylene group having 1 to 6 carbon atoms which may contain a carbonyl group, an ester group, an ether group or a hydroxy group, a straight chain alkylene group having 2 to 6 carbon atoms of the branch or an alkenylene group having a carbon number of 3 to 6 straight-chain, branched alkylene group of 2 to 6 carbon atoms or a cyclic alkylene group or a carbon number of 3 to 6 on the cyclic alkenyl group represents a group, or a phenylene group. R ^22, R R ²³ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁹ , R ³⁰ and R ³¹ each independently represents a straight chain alkyl group having 1 to 12 carbon atoms which may contain a carbonyl group, an ester group ether group or a hydroxyl group, A branched or cyclic alkyl group of 6 to 12 carbon atoms, an aralkyl group of 7 to 20 carbon atoms Z ¹ represents a single bond or a linear alkylene group having 1 to 12 carbon atoms which may contain an ether group, an ester group or a lactone ring, a branched alkylene group having 2 to 12 carbon atoms, a carbon number of 3 to 12 cyclic alkyl group, a cyclic, straight, or an alkenylene group having a carbon number of 3 to 12 on the branches of a carbon number of 2 to 12 represents a alkenyl group, or arylene group having a carbon number of 6~10. Z ² is a single bond -OR ³² -, or -C (= O) -Z ³ -R ³² -, Z ³ represents -O- or -NH-, and R ³ represents a hydrogen atom or a methyl group, R ³² is a straight chain alkylene or alkenylene group having 1 to 12 carbon atoms which may contain a carbonyl group, an ester group, an ether group or a hydroxyl group, a branched alkylene group or alkenylene group having 2 to 12 carbon atoms, A cyclic alkylene group or an alkenylene group, or a phenylene group C. M ^-. Represents a non-nucleophilic counter ion is d1~d3 represents a positive number satisfying 0≤d1≤0.5, 0≤d2≤0.5, 0≤d3≤0.5, and 0 <d1 + d2 + d3≤0.5 .) The resist material according to claim 1, further comprising an acid generator and an organic solvent. The resist material according to claim 1, further comprising a basic compound or a surfactant, or both. A pattern forming method comprising a step of applying the resist material of claim 1 on a substrate, a step of exposing the substrate to a high energy beam after the heat treatment, and a step of developing using a developer. The pattern forming method according to claim 11, wherein the high energy ray is i-line, KrF excimer laser, ArF excimer laser, electron beam, or extreme ultraviolet ray having a wavelength in the range of 3 to 15 nm.