KR20140117289A - Resist composition and method of forming resist - Google Patents

Abstract

Provided is a resist composition for forming a resist pattern having decreased roughness. For this, a resist composition is characterized by comprising a polymer compound having a constituting unit derived from an acrylic aid ester, in which a hydrogen atom combined with a carbon atom at an α position may be substituted with a substituent, the constituting unit having a lactone-containing cyclic group having an electron withdrawing group at the terminal of a side chain, and an acid generator composed of a compound represented by general formula (b1). In general formula (b1), R^101 is a cyclic group, an alkyl group of a chain type or an alkenyl group of a chain type that may have a substituent. q″ is an integer of 1-20. M^m^+ is an organic cation having m valency. [Chemical formula 1].

Description

RESIST COMPOSITION AND RESIST PATTERN FORMING METHOD

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

In lithography, for example, a resist film made of a resist material is formed on a substrate, a selective exposure is performed on the resist film, 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 exposure portion of the resist film changes in properties to be dissolved in the developing solution in a positive type and a resist portion in which the exposure portion is not dissolved in a developing solution is referred to as a negative type.

BACKGROUND ART [0002] In recent years, in the production of semiconductor devices and liquid crystal display devices, patterns are being rapidly miniaturized by advances in lithography techniques. As a method of refinement, generally, the exposure light source is shortened in wavelength (high energy). Specifically, conventionally, ultraviolet rays represented by g-line and i-line have been used, but now mass production of semiconductor devices using KrF excimer laser or ArF excimer laser has been started. EUV (extreme ultraviolet), EB (electron beam), X-ray and the like having a shorter wavelength (high energy) than these excimer lasers have also been studied.

Resist materials are required to have lithography properties such as sensitivity to resolution of these exposure light sources and resolving ability to reproduce patterns of fine dimensions.

As a resist material satisfying such a demand, a chemically amplified resist composition containing a base component whose solubility in a developing solution changes by the action of an acid and an acid generator component which generates an acid by exposure is conventionally used .

For example, when the developer is an alkali developing solution (alkali developing process), the positive chemical amplification type resist composition includes a resin component (base resin) that increases solubility in an alkali developing solution by the action of an acid, It is generally used to contain ingredients. When a resist film formed using such a resist composition is subjected to selective exposure at the time of forming a resist pattern, 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, The exposed portion becomes soluble in an alkali developing solution. For this reason, by the alkali development, a positive pattern in which the unexposed portion remains as a pattern is formed.

On the other hand, when such a chemically amplified resist composition is applied to a solvent developing process using a developing solution (organic developing solution) containing an organic solvent, the solubility of the organic developing solution relatively decreases as the polarity of the base resin increases, A negative resist pattern is formed in which the unexposed portion of the resist film is dissolved and removed by an organic developer to leave an exposed portion as a pattern. The solvent developing process for forming a negative resist pattern is sometimes referred to as a negative developing process (see, for example, Patent Document 1).

The base resin used in the chemically amplified resist composition generally has a plurality of constituent units for the purpose of improving the lithography characteristics and the like.

For example, in the case of a resin component whose solubility in an alkali developing solution increases due to the action of an acid, a constitutional unit containing an acid-decomposable group decomposed by the action of an acid generated from an acid generator or the like and having an increased polarity is used, In addition, structural units containing a lactone-containing cyclic group, structural units containing a polar group such as a hydroxyl group, and the like are used in combination (see, for example, Patent Document 2).

In recent years, along with progressive miniaturization of patterns, there is an increasing demand for polymer compounds useful as a base resin for a resist composition.

Among them, a polymer compound using, for example, a polycyclic structure containing an electron-withdrawing substituent group and a lactone skeleton as a monomer, and a resist composition containing the polymer compound have been proposed (see Patent Document 3).

Japanese Laid-Open Patent Publication No. 2009-025723 Japanese Patent Application Laid-Open No. 2003-241385 Japanese Laid-Open Patent Publication No. 2008-231059

In the progress of the lithography technique and the expansion of the application field, in the formation of the resist pattern, various kinds of lithography characteristics such as high sensitivity and roughness improvement are required more and more. However, for example, in the resist composition described in Patent Document 3, further improvement of the resist pattern, in particular the roughness, is required.

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 capable of forming a resist pattern with reduced roughness.

A first aspect of the present invention for solving the above problems is a resist composition comprising a base component (A) whose solubility in a developer is changed by the action of an acid and an acid generator component (B) Wherein the base component (A) comprises a polymeric compound (A1) having a structural unit (a0) represented by the following general formula (a0-1), wherein the acid generator component (B) and an acid generator (B1) comprising a compound represented by the following formula (b1).

[Chemical Formula 1]

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ⁰ is a divalent hydrocarbon group which may have a substituent. n _a0 is an integer of 0 to 2; Ra ¹ and Ra ² are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group or an alkylthio group, or Ra ¹ and Ra ² are bonded to each other to form an oxygen atom (-O-) May be an alkylene group having 1 to 6 carbon atoms, an ether linkage, or a thioether linkage which may contain a linking group (-S-). Ra ^'01 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydroxyalkyl group having 1 to 6 carbon atoms which may have a hydroxy group protected by a protective group and may have a halogen atom, a carboxyl group , Or a substituted oxycarbonyl group. 'When ⁰¹ is present, a plurality of Ra' 2 or more Ra ⁰¹ is the same or different to each other. X is a substituent selected from the group consisting of a halogen atom, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group and a cyano group. When two or more X's are present, the plurality of X's may be the same or different from each other. p ₀ is an integer of 0 to 8; q ₀ is an integer from 1 to 9.]

(2)

Wherein R ¹⁰¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. q " is an integer of 1 to 20; m is an integer of 1 or more, and M ^{m +} is an organic cation of m.

In a second aspect of the present invention, there is provided a process for producing a resist pattern, comprising the steps of: forming a resist film on a support using the resist composition of the first aspect of the invention; exposing the resist film; And a resist pattern forming method.

According to the resist composition and the resist pattern forming method of the present invention, a resist pattern with reduced roughness can be formed.

In the present specification and claims, the term " aliphatic " is defined as meaning a group, compound, or the like having no aromaticity as a relative concept to an aromatic.

Unless otherwise specified, the term " alkyl group " includes straight-chain, branched-chain and cyclic monovalent saturated hydrocarbon groups. The alkyl group in the alkoxy group is also the same.

The "alkylene group" includes straight-chain, branched-chain and cyclic divalent saturated hydrocarbon groups unless otherwise specified.

The "halogenated alkyl group" is a group in which a 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 a part or all of hydrogen atoms of an alkyl group or an alkylene group are substituted with a fluorine atom.

"Constituent unit" means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).

Includes the case of substituting a hydrogen atom (-H) with a monovalent group and the case of substituting a methylene group (-CH ₂ -) with a bivalent group when describing "may have a substituent".

&Quot; Exposure " is a concept including the entire irradiation of radiation.

The term "structural unit derived from an acrylate ester" means a structural unit constituted by cleavage of an ethylenic double bond of an acrylate ester.

"Acrylic acid ester" is a compound in which a hydrogen atom at the terminal of a carboxyl group of acrylic acid (CH ₂ ═CH-COOH) is substituted with an organic group.

The acrylate ester may have a hydrogen atom bonded to the carbon atom at the? -Position thereof substituted with a substituent. The substituent (R ^{? 0} ) for substituting a hydrogen atom bonded to the carbon atom at the ^{? -Position} is an atom or a group other than a hydrogen atom, and examples thereof include an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms have. Also, itaconic acid diesters in which a substituent (R ^{? 0} ) is substituted with a substituent containing an ester bond, or an? Hydroxyacrylic ester in which a substituent (R ^{? 0} ) is substituted with a hydroxyalkyl group or a group having a hydroxyl group- do. The carbon atom at the? -Position of the acrylate ester is a carbon atom to which a carbonyl group of acrylic acid is bonded, unless otherwise specified.

Hereinafter, an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the? -Position is substituted with a substituent is sometimes referred to as an? -Substituted acrylate ester. In some cases, an acrylic acid ester and an alpha-substituted acrylic acid ester are collectively referred to as " (alpha-substituted) acrylic ester ".

The term " structural unit derived from acrylamide " means a constituent unit in which an ethylenic double bond of acrylamide is cleaved.

The acrylamide may have a hydrogen atom bonded to the carbon atom at the? -Position thereof substituted with a substituent, and one or both of the hydrogen atoms of the amino group of the acrylamide may be substituted with a substituent. The carbon atom at the? -Position of acrylamide is a carbon atom to which a carbonyl group of acrylamide is bonded, unless otherwise specified.

Examples of the substituent substituting the hydrogen atom bonded to the carbon atom at the? -Position of the acrylamide include those exemplified as the substituent at the ^{? -Position} (substituent (R ^{? 0} )) in the? -Substituted acrylate ester.

The "structural unit derived from a hydroxystyrene or hydroxystyrene derivative" means a structural unit composed of an ethylene double bond of a hydroxystyrene or a hydroxystyrene derivative formed by cleavage.

The term " hydroxystyrene derivative " includes not only hydrogen atoms at the alpha -position of hydroxystyrene but also other substituents such as alkyl groups and halogenated alkyl groups, and derivatives thereof. Examples of the derivatives thereof include those obtained by substituting the hydrogen atom of the hydroxyl group of the hydroxystyrene which may be substituted with a hydrogen atom at the α-position with an organic group, a benzen ring of hydroxystyrene where the hydrogen atom at the α- And those having a substituent other than a hydroxyl group bonded thereto. The? Position (carbon atom at?) Refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.

Examples of the substituent substituting the hydrogen atom at the? -Position of hydroxystyrene include the same ones exemplified as the substituent at the? -Position in the? -Substituted acrylate ester.

The term " structural unit derived from vinylbenzoic acid or vinylbenzoic acid derivative " means a structural unit formed by cleavage of the ethylenic double bond of vinylbenzoic acid or vinylbenzoic acid derivative.

The term " vinylbenzoic acid derivative " means a vinylbenzoic acid in which hydrogen atoms at the alpha -position of vinylbenzoic acid are substituted with other substituents such as an alkyl group and a halogenated alkyl group, and derivatives thereof. Examples of the derivatives thereof include those obtained by substituting hydrogen atoms of the carboxyl groups of vinylbenzoic acid in which the hydrogen atom at the α-position may be substituted with organic groups, benzene rings of vinylbenzoic acid in which the hydrogen atom at the α-position may be substituted with substituents, And those having a substituent other than a carboxyl group bonded thereto. The? Position (carbon atom at?) Refers to a carbon atom to which a benzene ring is bonded, unless otherwise specified.

The term " styrene " includes the concept that hydrogen atoms at the [alpha] -position of styrene and styrene are substituted with other substituents such as an alkyl group and a halogenated alkyl group.

"Constituent unit derived from styrene" and "constituent unit derived from styrene derivative" means a constituent unit in which an ethylene double bond of styrene or a styrene derivative is cleaved.

The alkyl group as the substituent at the? -Position is preferably a linear or branched alkyl group, and specifically includes an alkyl group having 1 to 5 carbon atoms such as methyl, ethyl, propyl, isopropyl, Butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group).

Specific examples of the halogenated alkyl group as the substituent at the? -Position include a group obtained by substituting a part or all of the hydrogen atoms of the alkyl group as the substituent at the? -Position 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.

Specific examples of the hydroxyalkyl group as the substituent at the? -Position include a group in which a part or all of the hydrogen atoms of the "alkyl group as the substituent at the? -Position" are substituted with hydroxyl groups. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.

&Quot; Resist composition &

The resist composition of the first embodiment of the present invention is a resist composition comprising a base component (A) (hereinafter also referred to as "component (A)") whose solubility in a developer changes by the action of an acid and an acid generator (B) (hereinafter also referred to as " component (B) ").

When a resist film is formed using such a resist composition and selectively exposed to the resist film, an acid is generated in the exposed portion, and the solubility of the component (A) in the developer is changed by the action of the acid, In the light portion, since the solubility of the component (A) in the developer does not change, there is a difference in solubility in the developer between the exposed portion and the unexposed portion. Therefore, when the resist film is developed, when the resist composition is a positive type, the exposed portion is dissolved and removed to form a positive resist pattern. When the resist composition is negative, the unexposed portion is dissolved and removed to form a negative resist pattern .

In the present specification, a resist composition that forms a positive resist pattern by dissolving and removing the exposed portions is referred to as a positive resist composition, and a negative resist composition that forms a negative resist pattern by dissolving and removing the unexposed portion is referred to as a negative resist composition.

The resist composition of the present embodiment may be a positive resist composition or a negative resist composition.

The resist composition of the present embodiment may be used for an alkali development process using an alkali developer for development processing at the time of forming a resist pattern, and may be used for a solvent development process using a developer (organic developer) containing an organic solvent .

≪ Component (A) >

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 a nano-level resist pattern is easily formed.

Organic compounds used as a base component are roughly divided into non-polymeric and non-polymeric polymers.

As the non-polymeric polymer, those having a molecular weight of usually 500 or more and less than 4000 are used. Hereinafter, the term " low molecular weight compound " refers to a non-polymeric substance having a molecular weight of 500 or more and less than 4000.

As the polymer, those having a molecular weight of 1000 or more are usually used. Hereinafter, the term "resin" or "polymer compound" refers to a polymer having a molecular weight of 1000 or more.

As the molecular weight of the polymer, a mass average molecular weight in terms of polystyrene by GPC (Gel Permeation Chromatography) is used.

In the case where the resist composition of the present embodiment is a "negative resist composition for alkali development process" in which a negative resist pattern is formed in an alkali developing process, or a "negative resist composition for alkali developing process" for forming a positive resist pattern in a solvent developing process (Hereinafter referred to as "component (A-2)") is preferably used as the component (A), and the crosslinking agent ≪ / RTI > When an acid is generated from the component (B) by exposure, the acid acts to cross-link the component (A-2) and the crosslinking agent component. As a result, the resist composition has reduced solubility in an alkali developing solution To increase the solubility in the solution. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the resist composition onto a support is selectively exposed, the exposed portion is changed to an insoluble (soluble in an organic developer) to an alkaline developer, Since it does not change with solubility (insolubility with an organic developer) for a developer, a negative resist pattern is formed by development with an alkaline developer. At this time, a positive type resist pattern is formed by developing with an organic developing solution.

As the component (A-2), a resin soluble in an alkali developer (hereinafter referred to as "alkali-soluble resin") is used.

As the alkali-soluble resin, for example, an alkylester of? - (hydroxyalkyl) acrylic acid or? - (hydroxyalkyl) acrylic acid (preferably an alkylester of 1 to 20 carbon atoms, 5, an acrylic resin which is disclosed in U.S. Patent No. 6949325, in which a hydrogen atom bonded to the carbon atom at the? -Position having a sulfonamide group may be substituted with a substituent, or a resin having a unit derived from at least one selected from the group consisting of Polycycloolefin resins, which are disclosed in U.S. Patent Nos. 6949325, 2005-336452, and 2006-317803, which contain a fluorinated alcohol and in which hydrogen atoms bonded to carbon atoms at the [alpha] An acrylic resin which may be substituted; an acrylic resin having a fluorinated alcohol, which is disclosed in JP-A-2006-259582 The Li cycloolefin resin or the like, it is preferable because the swelling to form a less good resist pattern.

The above-mentioned? - (hydroxyalkyl) acrylic acid may be obtained by copolymerizing an acrylic acid in which a hydrogen atom is bonded to a carbon atom at the? -Position to which a carboxyl group is bonded, among the acrylic acid in which a hydrogen atom bonded to the carbon atom at? refers to one or both of? -hydroxyalkyl acrylic acid to which a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) is bonded to a carbon atom at? -position.

As the crosslinking agent component, for example, an amino-based crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group, a melamine-based crosslinking agent or the like is preferably used because a good resist pattern with less swelling can be formed. The blending amount of the crosslinking agent component is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the alkali-soluble resin.

In the case where the resist composition of the present embodiment is a "positive resist composition for alkali development process" in which a positive resist pattern is formed in an alkali development process, or a "solvent development process" in which a negative resist pattern is formed in a solvent development process (Hereinafter referred to as the "(A-1) component") in which the polarity increases due to the action of an acid, is preferably used as the component (A) Is used. By using the component (A-1), since the polarity of the base component changes before and after the exposure, a good development contrast can be obtained not only in the alkali development process but also in the solvent development process.

In the case of applying the alkali development process, the component (A-1) is poorly soluble in an alkali developing solution before exposure, and when an acid is generated by exposure, the polarity increases due to the action of the acid, . Therefore, in the formation of a resist pattern, when the resist film obtained by applying the resist composition onto a support is selectively exposed, the exposed portion changes from being poorly soluble to soluble in an alkaline developer, while the unexposed portion is alkali- The positive resist pattern is formed by alkali development.

On the other hand, in the case of applying the solvent developing process, the component (A-1) has high solubility in an organic developing solution before exposure, and when acid is generated by exposure, the polarity is increased by the action of the acid, Lt; / RTI > Therefore, in forming a resist pattern, when the resist film obtained by applying the resist composition onto a support is selectively exposed, the exposed portion changes from soluble to poorly soluble in the organic developer, while the unexposed portion remains soluble It is possible to obtain contrast between the exposed portion and the unexposed portion to form a negative resist pattern.

The component (A) used in the resist composition of the present embodiment contains the polymer compound (A1) having the structural unit (a0) represented by the general formula (a0-1) (hereinafter referred to as the component (A1) will be.

As the component (A), at least the component (A1) is used, and the polymer compound and / or the low molecular compound other than the component (A1) may be used in combination.

In the resist composition of the present embodiment, the component (A) is preferably the component (A-1). That is, the resist composition of the present embodiment can be used in a "positive resist composition for alkali development process" for forming a positive resist pattern in an alkali developing process, or a "positive resist composition for forming a negative resist pattern in a solvent developing process" Quot; negative resist composition " In addition, it is preferable that the component (A-1) includes the component (A1).

[Component (A1)] [

The component (A1) is a polymer compound having the structural unit (a0) represented by the general formula (a0-1).

(Constituent unit (a0))

The structural unit (a0) is a structural unit represented by the following general formula (a0-1). In the resist pattern formation, the use of the polymer compound having the constituent unit (a0) as a base resin is effective for high sensitivity.

(3)

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ⁰ is a divalent hydrocarbon group which may have a substituent. n _a0 is an integer of 0 to 2; Ra ¹ and Ra ² are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group or an alkylthio group, or Ra ¹ and Ra ² are bonded to each other to form an oxygen atom (-O-) May be an alkylene group having 1 to 6 carbon atoms, an ether linkage, or a thioether linkage which may contain a linking group (-S-). Ra ^'01 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydroxyalkyl group having 1 to 6 carbon atoms which may have a hydroxy group protected by a protective group and may have a halogen atom, a carboxyl group , Or a substituted oxycarbonyl group. 'When ⁰¹ is present, a plurality of Ra' 2 or more Ra ⁰¹ is the same or different to each other. X is a substituent selected from the group consisting of a halogen atom, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group and a cyano group. When two or more X's are present, the plurality of X's may be the same or different from each other. p ₀ is an integer of 0 to 8; q ₀ is an integer from 1 to 9.]

In the formula (a0-1), the alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group, An isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group and a neopentyl group.

The halogenated alkyl group having 1 to 5 carbon atoms is a group in which a part or all of the hydrogen atoms of the "alkyl group having 1 to 5 carbon atoms in R" 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 having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is particularly preferable for industrial availability.

In the formula (a0-1), Va ⁰ is a divalent hydrocarbon group which may have a substituent.

The hydrocarbon group of Va ⁰ 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 the divalent hydrocarbon group in Va ⁰ may be saturated or unsaturated, and is preferably saturated.

More specifically, examples of the aliphatic hydrocarbon group in Va ⁰ include a linear or branched aliphatic hydrocarbon group or an aliphatic hydrocarbon group containing a ring in the structure.

Va ⁰ may have a substituent. Include those having a case which is substituted with a divalent, ether bond between the carbon atoms of the divalent hydrocarbon group of ⁰ Va group (-O-) - for example, a methylene group (-CH ₂₎ in the hydrocarbon groups Va ⁰ . In this case, the number of ether bonds present in Va ⁰ may be one or two. In addition, a case where the hydrogen atom (-H) in the hydrocarbon groups are substituted with ⁰ Va monovalent, fluorinated alkyl group with a hydrogen atom (-H) in the hydrocarbon groups of Va ⁰ is a fluorine atom or having 1 to 5 carbon atoms And substituted ones. Va to ⁰ in this _{case, -CH 2 CHF-, -CH (CH} 2 CH 3) CF 2 -, -CH (CH 2 CH 3) C (CF 3) F-, -CH (CH 3) CF 2 - is preferred.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -], a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

Aliphatic hydrocarbon group of the branched, and preferably an alkylene group of branched, _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include alicyclic hydrocarbon groups (groups in which two hydrogen atoms have been removed from the aliphatic hydrocarbon ring), groups in which alicyclic hydrocarbon groups are bonded to the ends of a linear or branched aliphatic hydrocarbon group , And groups in which an alicyclic hydrocarbon group is introduced in the midst of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same ones as described above.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the 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 thereof include cyclopentane, cyclohexane, and the like.

The polycyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, iso Borane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group in Va ⁰ is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 p-electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocyclic rings in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include groups in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group), aromatic compounds containing two or more aromatic rings (for example, A group in which one hydrogen atom of a group (aryl or heteroaryl group) in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group For example, by further removing one hydrogen atom from an aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, And the like. The number of carbon atoms of the alkylene group bonded to the aryl group or the heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In the above formula (a0-1), n _a0 is an integer of 0 to 2, preferably 0 or 1, and more preferably 0.

Ra ¹ and Ra ² each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or an alkylthio group, or Ra ¹ and Ra ² are bonded to each other to form an oxygen An alkylene group having 1 to 6 carbon atoms which may contain an atom (-O-) or a sulfur atom (-S-), an ether bond, or a thioether bond.

The alkyl group having 1 to 5 carbon atoms in Ra ¹ and Ra ² is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specific examples thereof include 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 alkoxy group in Ra ¹ and Ra ² is preferably a linear or branched chain type. Concretely, the alkyl group exemplified as the alkyl group in Ra ¹ and Ra ² and the oxygen atom (-O-) are connected to each other .

The alkylthio group in Ra ¹ and Ra ² preferably has 1 to 4 carbon atoms, and specific examples thereof include methylthio group, ethylthio group, n-propylthio group, isopropylthio group, n-butylthio group, tert-butylthio group.

Further, an alkylene group, an ether bond, Ra ¹ and Ra ² is, Ra ¹ and Ra ² is 1 to 6 carbon atoms bonded to each other, which may contain an oxygen atom (-O-) or a sulfur atom (-S-) ( -O-) or a thioether bond (-S-).

The alkylene group having 1 to 6 carbon atoms formed by bonding of Ra ¹ and Ra ² is preferably a linear or branched alkylene group, more preferably a methylene group, an ethylene group, an n-propylene group, . When the alkylene group includes an oxygen atom or a sulfur atom, specific examples thereof include a group in which -O- or -S- is interposed between the terminal or carbon atom of the alkylene group, and for example, -O- CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH ₂ - and the like. The group formed by bonding Ra ¹ and Ra ² to each other is preferably an alkylene group having 1 to 6 carbon atoms or -O-, more preferably an alkylene group having 1 to 6 carbon atoms, and an alkylene group having 1 to 5 carbon atoms And a methylene group is particularly preferable.

Ra < ⁰¹ > represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a hydroxy group portion protected by a protecting group and may have a halogen atom A hydroxyalkyl group, a carboxyl group forming a salt, or a substituted oxycarbonyl group.

Examples of the alkyl group having 1 to 6 carbon atoms in Ra ^'01 include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, Of these, an alkyl group having 1 to 5 carbon atoms is preferable, an alkyl group having 1 to 4 carbon atoms is more preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group or an ethyl group is more preferable. Particularly preferably a methyl group. Examples of the halogen atom which Ra < ⁰¹ > may have in the alkyl group having 1 to 6 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group having 1 to 6 carbon atoms having a halogen atom include a chloroalkyl group such as a chloromethyl group, a fluoroalkyl group such as a trifluoromethyl group, a 2,2,2-trifluoroethyl group, and a pentafluoroethyl group Preferably a fluoroalkyl group having 1 to 3 carbon atoms), and the like.

Examples of the hydroxyalkyl group having 1 to 6 carbon atoms in Ra ^'01 include a hydroxymethyl group, a 2-hydroxyethyl group, a 1-hydroxyethyl group, a 3-hydroxypropyl group, a 2- Group, a 4-hydroxybutyl group, and a 6-hydroxyhexyl group. Examples of the halogen atom of Ra ^'01 which may have a hydroxyalkyl group having 1 to 6 carbon atoms include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable. Examples of the C1-C6 hydroxyalkyl group having a halogen atom include a difluorohydroxymethyl group, a 1,1-difluoro-2-hydroxyethyl group, a 2,2-difluoro-2- Hydroxyethyl group, 1,1,2,2-tetrafluoro-2-hydroxyethyl group and the like. Of the hydroxyalkyl groups having 1 to 6 carbon atoms which may have a halogen atom, a hydroxyalkyl group having 1 to 3 carbon atoms which may have a halogen atom is preferable, and a hydroxyalkyl group having 1 or 2 carbon atoms (preferably 1 carbon atom) Or a hydroxyalkyl group having a halogen atom having 1 or 2 carbon atoms (preferably 1 carbon atom) is more preferable.

Examples of the protecting group for protecting the hydroxyl group of the C1-C6 hydroxyalkyl group which may have a halogen atom include an ether bond or an acetal group together with an oxygen atom constituting a hydroxy group such as a methyl group or a methoxymethyl group, A group forming a bond, and a group forming an ester bond together with an oxygen atom constituting a hydroxy group such as an acetyl group or a benzoyl group.

Examples of the carboxyl group (salt of a carboxyl group) forming a salt in Ra ^'01 include an alkali metal salt, an alkaline earth metal salt and a transition metal salt.

Examples of the substituted oxycarbonyl group in Ra ^'01 include an alkoxycarbonyl group (specifically, an alkoxycarbonyl group, an ethoxycarbonyl group, an isopropyloxycarbonyl group, an n-propyloxycarbonyl group, An alkoxycarbonyl group such as a vinyloxycarbonyl group and an allyloxycarbonyl group), a cycloalkyloxycarbonyl group such as a cyclohexyloxycarbonyl group, and an aryloxycarbonyl group such as a phenyloxycarbonyl group.

'When ⁰¹ is present, a plurality of Ra' in the structural unit represented by the above formula (a0-1), 2 Ra ⁰¹ or more is also the same or different from each other.

Ra < ⁰¹ > is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydroxyalkyl group having 1 to 6 carbon atoms which may have a hydroxy group protected by a protecting group and may have a halogen atom, A carbonyl group is preferred.

Among the alkyl groups having 1 to 6 carbon atoms which may have a halogen atom, an alkyl group having 1 to 3 carbon atoms or a halogenated alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group and a trifluoromethyl group are particularly preferable.

Among the hydroxyalkyl groups having 1 to 6 carbon atoms which may have a hydroxy group protected by a protecting group and may also have a halogen atom, a hydroxyalkyl group having 1 to 3 carbon atoms, in which the hydroxy moiety may be protected by a protective group, A hydroxyalkyl group having a halogen atom whose hydroxyl group portion may be protected by a protecting group is preferable and a hydroxymethyl group in which a hydroxy group is protected by a protecting group such as an acetoxymethyl group is more preferable.

In the above formula (a0-1), X is a substituent selected from the group consisting of a halogen atom, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group and a cyano group.

Examples of the halogen atom in X include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

Examples of the alkoxycarbonyl group in X include a methoxycarbonyl group and the like.

Examples of the acyl group in X include an acetyl group and the like.

When two or more X's are present in the structural unit represented by the above formula (a0-1), the plurality of X's may be mutually the same or different.

X is preferably a halogen atom (preferably a fluorine atom), a carboxyl group, an alkoxycarbonyl group (preferably a methoxycarbonyl group), an acyl group (preferably an acetyl group), a cyano group, A nitro group is preferable, and a cyano group is particularly preferable.

In the above formula (a0-1), p ₀ is an integer of 0 to 8, preferably 0 to 6, and more preferably 0 to 3.

In the above formula (a0-1), q ₀ is an integer of 1 to 9, preferably an integer of 1 to 5, more preferably 1 or 2.

In the formula (a0-1), when Ra ¹ and Ra ² do not bond to each other, X represents a 1-position, a 2-position, a 3-position, or a 3-position of the 6-oxabicyclo [3.2.1 ^1,5 ] (The α position of the lactone) or the position of the 2-position, and among them, the 1-position (the α-position of the lactone) may be bonded at any position among the 4-position, Of the present invention.

When Ra ¹ and Ra ² are bonded to each other, X is preferably selected from the group consisting of 1-position, 4-position, 5-position, 6-position, 7-position, 8-oxatricyclo [4.2.1.0 ^4,8 ] Position or 9-position, and may be bonded at any position of the 3-oxatricyclo [4.2.1.0 ^4,8 ] nonane ring at the 1-position or 9-position (or a position equivalent thereto) , And it is particularly preferable that they are bonded at the position of 1 position (or a position corresponding thereto, position of alpha of the lactone).

Specific examples of the structural unit (a0) are shown below. In the following formulas, R ^{? Represents} a hydrogen atom, a methyl group or a trifluoromethyl group. X is the same as X in the above formula (a0-1).

[Chemical Formula 4]

[Chemical Formula 5]

The constituent unit (a0) of the component (A1) may be one type or two or more types.

The proportion of the structural unit (a0) in the component (A1) is preferably from 5 to 70% by mole, more preferably from 10 to 60% by mole, more preferably from 10 to 60% by mole based on the total of all the structural units constituting the component (A1) To 50 mol%, and particularly preferably 10 mol% to 40 mol%.

By setting the ratio of the constituent unit (a0) to a preferable upper limit value or less, a resist pattern of good shape is easily obtained while maintaining high sensitivity. On the other hand, when the value is set to a preferable lower limit value or more, the sensitivity is increased and lithography characteristics such as resolution and exposure margin (EL margin) are improved.

(Other constituent units)

The component (A1) may further contain another structural unit in addition to the structural unit (a0).

The other structural unit is not particularly limited as long as it is a structural unit that can not be classified as the above-mentioned structural unit (a0), and can be used for ArF excimer laser, KrF excimer laser (preferably ArF excimer laser) A large number of conventionally known ones can be used for the resin. Examples thereof include the following structural units (a1) to (a4) and structural units that generate an acid upon exposure.

Constitutional unit (a1):

In the resist composition of the present embodiment, it is preferable that the component (A1) has a structural unit (a1) comprising an acid-decomposable group whose polarity is further increased by the action of an acid in addition to the structural unit (a0).

When the resist composition of the present embodiment contains a polymer compound having the constituent unit (a0) and the constituent unit (a1), when the resist film formed by using the resist composition is exposed, the constituent unit (a1) The action of the acid causes cleavage of at least part of the bonds in the structure, and the polarity is increased. As described above, since the polarity of the component (A1) changes before and after exposure, by using the component (A1), a satisfactory development contrast can be obtained not only in the alkali developing process but also in the solvent developing process. The resist composition of the present embodiment becomes a positive type in the alkali development process and becomes a negative type in the solvent development process.

The "acid-decomposable group" is an acid-decomposable group capable of cleaving at least a part of bonds in the structure of the acid decomposable group by the action of an acid.

Examples of the acid decomposable group whose polarity is increased by the action of an acid include a group which is decomposed by the action of an acid to generate a polar group.

Examples of the polar group include a carboxyl group, a hydroxyl group, an amino group, and a sulfo group (-SO ₃ H). Among them, a polar group containing -OH in the structure (hereinafter sometimes referred to as "OH-containing polar group") is preferable, a carboxyl group or a hydroxyl group is more preferable, and a carboxyl group is particularly preferable.

As the acid decomposable group, more specifically, there can be mentioned a group in which the polar group is protected with an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected with an acid dissociable group).

The term "acid dissociable group" as used herein refers to a group having acid dissociable property capable of cleaving a bond between the acid dissociable group and an atom adjacent to the acid dissociable group by the action of an acid, or (ii) Refers to both groups in which a bond between an acid dissociable group and an atom adjacent to the acid dissociable group is cleaved by the occurrence of a further decarboxylation reaction after cleavage of a part of bonds by the action of an acid.

The acid dissociable group constituting the acid-decomposable group is required to be a group having a lower polarity than the polar group generated by dissociation of the acid dissociable group, and when the acid dissociable group is dissociated by the action of an acid, Polarity with higher polarity than genitalia is generated and polarity is increased. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developer relatively changes. When the developer is an alkaline developer, the solubility increases. When the developer is an organic developer, the solubility decreases.

Examples of the acid dissociable group include those proposed as acid dissociable groups of base resins for chemically amplified resists.

Acid-dissociable group of a base resin for a chemically amplified resist, and specific examples thereof include "acetal type acid dissociable group", "tertiary alkyl ester acid dissociable group", "tertiary Alkyloxycarbonyl acid dissociable group ".

· Acetal type acid dissociation type:

Examples of the acid dissociable group for protecting the carboxyl group or the hydroxyl group in the polar group include an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter may be referred to as "acetal type acid dissociable group" .

[Chemical Formula 6]

Wherein Ra ' ¹ and Ra' ² are each a hydrogen atom or an alkyl group, and Ra ' ³ is a hydrocarbon group, and Ra' ³ may be bonded to any of Ra ' ¹ and Ra' ² to form a ring]

In formula (a1-r-1), at least one of Ra ' ¹ and Ra' ² is preferably a hydrogen atom, and more preferably both hydrogen atoms.

When Ra ' ¹ or Ra' ² is an alkyl group, examples of the alkyl group include the same alkyl groups exemplified as substituent groups which may be bonded to carbon atoms at the α-position in the description of the α-substituted acrylate ester. An alkyl group having a carbon number of 5 to 5 is preferable. Specifically, the alkyl group is preferably a linear or branched alkyl group. Specific examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl and neopentyl. More preferably a methyl group is particularly preferable.

In the formula (a1-r-1), examples of the hydrocarbon group of Ra ' ³ include a linear or branched alkyl group and a cyclic hydrocarbon group.

The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group and an n-pentyl group. Among them, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

The branched alkyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5 carbon atoms. Specific examples thereof include isopropyl, isobutyl, tert-butyl, isopentyl, neopentyl, 1,1-diethylpropyl and 2,2-dimethylbutyl. .

When Ra ' ³ is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, a polycyclic group or a monocyclic group.

The aliphatic hydrocarbon group which is a monocyclic group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like.

The aliphatic hydrocarbon group which is a polycyclic group is preferably a group in which one hydrogen atom has been removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, iso Borane, tricyclodecane, tetracyclododecane and the like.

When the cyclic hydrocarbon group of Ra ' ³ is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 < [pi] > electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocyclic rings in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group in Ra ' ³ include groups in which one hydrogen atom is removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring (an aryl group or a heteroaryl group); aromatic compounds containing two or more aromatic rings A group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring or aromatic heterocyclic ring, a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group (e.g., a benzyl group, a phenethyl group, a 1 Naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group and 2-naphthylethyl group), and the like. The number of carbon atoms of the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

When Ra ' ³ is bonded to 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 a tetrahydropyranyl group, a tetrahydrofuranyl group, and the like.

· Tertiary alkyl ester type acid dissociable group:

Among the polar groups, examples of the acid dissociable groups for protecting the carboxyl group include acid dissociable groups represented by the following general formula (a1-r-2). Further, hereinafter, for the sake of convenience, what is constituted by an alkyl group in the acid dissociable group represented by the following formula (a1-r-2) may be referred to as " tertiary alkyl ester-type acid dissociable group ".

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Wherein Ra ' ⁴ to Ra' ⁶ each represent a hydrocarbon group, and Ra ' ⁵ and Ra' ⁶ may combine with each other to form a ring.

Examples of the hydrocarbon group of Ra ' ⁴ to Ra' ^{6 include} the same groups as those of Ra ' ³ above.

Ra ' ⁴ is preferably an alkyl group having 1 to 5 carbon atoms. When Ra ' ⁵ and Ra' ⁶ are bonded to each other to form a ring, there may be mentioned groups represented by the following general formula (a1-r2-1). On the other hand, when Ra ' ⁴ to Ra' ⁶ do not bond to each other and are independent hydrocarbon groups, there may be mentioned groups represented by the following general formula (a1-r2-2).

[Chemical Formula 8]

[Wherein, Ra represents a hydrocarbon group, each is ¹² ~ Ra ^'14' group, Ra to form an aliphatic cyclic group together with the carbon atom of ¹⁰ combines' ¹⁰ is an alkyl group, Ra of 1 to 10 carbon atoms, ¹¹ is Ra independently .]

Equation (a1-r2-1) of, groups exemplified as the "Ra in the alkyl group is formulas (a1-r-1) of 1 to 10 carbon atoms in the ^{10 '3} linear or branched alkyl group of Ra desirable. Equation (a1-r2-1) of, Ra 'is Ra ^11' to ¹⁰ aliphatic cyclic group formed together with the carbon atoms bonded to the formula (a1-r-1) Ra '3 sentence of monocyclic or polycyclic in The group exemplified as a group-derived aliphatic hydrocarbon group is preferable.

Equation (a1-r2-2) of, Ra ', and Ra ^{12' 14} Ra is ³ 'of the each independently preferably an alkyl group of 1 to 10 carbon atoms, and the alkyl group has the formula (a1-r-1) More preferably a straight chain or branched alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group.

Equation (a1-r2-2) of Ra 'is ^13, formula (a1-r-1) Ra of the' ³ a linear or branched alkyl group, a monocyclic or polycyclic group of the sentence illustrated by way of a hydrocarbon group And is preferably an aliphatic hydrocarbon group. Among them, it is more preferable to be a group exemplified as a monocyclic group of Ra ' ³ or an aliphatic hydrocarbon group of a polycyclic group.

Specific examples of the group represented by the formula (a1-r2-1) are shown below. * Indicates a combined hand (hereinafter, the same in this specification).

[Chemical Formula 9]

[Chemical formula 10]

Specific examples of the groups represented by the above formula (a1-r2-2) are shown below.

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· Tertiary alkyloxycarbonyl acid dissociable group:

Examples of the acid dissociable group for protecting the hydroxyl group in the polar group include an acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as " tertiary alkyloxycarbonyl acid dissociable group & There are cases).

[Chemical Formula 12]

Wherein Ra ' ⁷ to Ra' ⁹ each represent an alkyl group.

In the formula (a1-r-3), each of Ra ' ⁷ to Ra' ⁹ is preferably an alkyl group having 1 to 5 carbon atoms, more preferably 1 to 3.

The total carbon number of each alkyl group is preferably from 3 to 7, more preferably from 3 to 5, and most preferably from 3 to 4.

Examples of the structural unit (a1) include a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent, a structural unit derived from acrylamide, a structure derived from a hydroxystyrene or a hydroxystyrene derivative , At least a part of the hydrogen atoms in the hydroxyl group of the unit is protected by a substituent containing the acid-decomposable group, a hydrogen atom in the -C (= O) -OH of the constituent unit derived from vinylbenzoic acid or vinylbenzoic acid derivative And structural units in which at least a part of the atoms are protected by a substituent including the acid-decomposable group.

As the structural unit (a1), a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent is preferable.

Specific examples of such a structural unit (a1) include a structural unit represented by the following general formula (a1-1) or (a1-2).

[Chemical Formula 13]

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group which may have an ether bond, n _a1 is 0 to 2, and Ra ¹ is an acid dissociable group represented by the formula (a1-r-1) or (a1-r-2). Ra ¹ is an acid dissociable group represented by the above formula (a1-r-1) or (a1-r-3). Wa ¹ is a hydrocarbon group of n _a2 +1 valency, n _a2 is 1 to 3,

In the formula (a1-1), the alkyl group having 1 to 5 carbon atoms represented by R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group, An n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms is 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 having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable for industrial availability.

In the formula (a1-1), the bivalent hydrocarbon group which may have an ether bond of Va ¹ is the same as the case where Va ⁰ in the formula (a0-1) is a bivalent hydrocarbon group which may have an ether bond as a substituent Do.

In the formula (a1-2), the hydrocarbon group of n _a2 +1 valency 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, and may be saturated or unsaturated, and is usually saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a combination of a linear or branched aliphatic hydrocarbon group and a ring-containing aliphatic hydrocarbon group One can say.

The n _a2 + 1 is preferably 2 to 4, more preferably 2 or 3.

Specific examples of the structural unit represented by the formula (a1-1) are shown below. In the following formulas, R ^{? Represents} a hydrogen atom, a methyl group or a trifluoromethyl group.

[Chemical Formula 14]

[Chemical Formula 15]

[Chemical Formula 16]

[Chemical Formula 17]

[Chemical Formula 18]

Specific examples of the structural unit represented by the formula (a1-2) are shown below.

[Chemical Formula 19]

The structural unit (a1) of the component (A1) may be one kind or two or more kinds.

When the component (A1) has the structural unit (a1), the proportion of the structural unit (a1) in the component (A1) is preferably from 1 to 50 mol% relative to the total of all the structural units constituting the component (A1) , More preferably 5 to 45 mol%, and still more preferably 5 to 40 mol%.

By setting the ratio of the constituent unit (a1) to the lower limit value or more, a resist pattern can be easily obtained, and lithography characteristics such as sensitivity, resolution, roughness improvement or EL margin can be improved. In addition, by keeping the value below the upper limit value, balance with other constituent units can be obtained.

The structural unit (a2):

In the resist composition of the present embodiment, it is preferable that the component (A1) further contains, in addition to the structural unit (a0) and the structural unit (a1), a lactone-containing cyclic group, -SO ₂ -containing cyclic group or a carbonate- It is preferable to have the structural unit (a2) (except for the structural unit (a0)).

The lactone-containing cyclic group, -SO ₂ -containing cyclic group or carbonate-containing cyclic group of the constituent unit (a2) is preferably a cyclic group which is effective in improving the adhesion of the resist film to the substrate will be. By having the structural unit (a2), the solubility of the resist film in an alkali developer becomes high during the alkali development process.

The "lactone-containing cyclic group" refers to a cyclic group containing a ring (lactone ring) containing -O-C (═O) - in the cyclic backbone. When a lactone ring is counted as the first ring, only a lactone ring is referred to as a monocyclic ring, and when it has another ring structure, it is referred to as a polycyclic ring regardless of its structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.

The lactone-containing cyclic group in the structural unit (a2) is not particularly limited, and any cyclic group can be used. Specifically, the groups represented by the following general formulas (a2-r-1) to (a2-r-7) are exemplified.

[Chemical Formula 20]

[Wherein, Ra ^'21 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, -COOR'', -OC (= O) R'', hydroxy alkyl group or a cyano group; R "is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group; A" includes an oxygen atom (-O-) or a sulfur atom (-S-) An oxygen atom or a sulfur atom, n 'is an integer of 0 to 2, and m' is 0 or 1.]

The alkyl group in the general formula (a2-r-1) ~ (a2-r-7) of the Ra ^'21 is an alkyl group having 1 to 6 carbon atoms are preferred. The alkyl group is preferably a linear or branched chain. Specific examples include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl and hexyl. Among them, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.

Ra 'The alkoxy group in ²¹ is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably a linear or branched chain. Specifically, there is a group with an oxygen atom (-O-) exemplified as the alkyl group in the above-mentioned Ra ^'21 include groups attached.

Ra 'is a halogen atom in the ^21, and a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom is preferable.

Ra 'with a halogenated alkyl group in the ^21, wherein Ra' may be a group in which some or all of the hydrogen atoms of the alkyl group in ²¹ with the halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.

'In, R, Ra, of ²¹ in -COOR'', -OC (= O) R'' is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or -SO ₂ - containing ring It is a penalty.

The alkyl group in R " may be any of linear, branched, and 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, particularly preferably a methyl group or an ethyl group.

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, there may be mentioned a group obtained by removing one or more hydrogen atoms from a monocycloalkane which may be substituted with a fluorine atom or a fluorinated alkyl group and which may not be substituted, a polycycloalkane such as a bicycloalkane, a tricycloalkane or a tetracycloalkane A group in which one or more hydrogen atoms have been removed, and the like. More specifically, there may be mentioned groups obtained by removing one or more hydrogen atoms from a monocycloalkane such as cyclopentane, cyclohexane and the like; a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane and tetracyclododecane And a group obtained by removing one or more hydrogen atoms from the hydrogen atom.

Examples of the lactone-containing cyclic group in R "include the same groups as those represented by the general formulas (a2-r-1) to (a2-r-7).

The carbonate-containing cyclic group in R "is the same as the carbonate-containing cyclic group described later, and concretely includes groups represented by the general formulas (ax3-r-1) to (ax3-r-3) .

-SO ₂ of the R '' - containing a cyclic group, which will be described later -SO ₂ - the same as that containing cyclic group, and specifically by the following formula (a5-r-1) ~ (a5-r-4) And the like.

Ra 'hydroxy group in ²¹ is preferably a carbon number of 1 to 6, specifically, the Ra' One or more of the hydrogen atoms of the alkyl group in ²¹ may be a substituted by a hydroxyl group.

Examples of the alkylene group having 1 to 5 carbon atoms in A "in the general formulas (a2-r-2), (a2-r-3) and (a2- Alkylene group is preferable, and a methylene group, an ethylene group, an n-propylene group, an isopropylene group and the like can be given. When the alkylene group includes an oxygen atom or a sulfur atom, specific examples thereof include a group in which -O- or -S- is interposed between the terminal or carbon atom of the alkylene group, for example, -O- CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH ₂ - and the like. A "is preferably an alkylene group of 1 to 5 carbon atoms or -O-, more preferably an alkylene group of 1 to 5 carbon atoms, and most preferably a methylene group.

Specific examples of the groups represented by the general formulas (a2-r-1) to (a2-r-7) are described below.

[Chemical Formula 21]

[Chemical Formula 22]

The "-SO ₂ -containing cyclic group" refers to a cyclic group containing a ring containing -SO ₂ - in the cyclic backbone, and specifically, the sulfur atom (S) in -SO ₂ - Is a cyclic group that forms part of the ring skeleton of < RTI ID = 0.0 > A ring containing -SO ₂ - in the ring skeleton is counted as the first ring, and when the ring is only a ring, it is called a monocyclic ring, and in the case of having another ring structure, it is called a ring ring regardless of its structure. The -SO ₂ -containing cyclic group may be a monocyclic group or a polycyclic group.

-SO ₂ - containing cyclic group are, in particular, those in the ring skeleton -O-SO ₂ - sultone (sultone) of the -OS- of forms part of the ring backbone-cyclic group containing, i.e. -O-SO ₂ And is preferably a cyclic group containing a ring.

Specific examples of the -SO ₂ -containing cyclic group include the groups represented by the following general formulas (a5-r-1) to (a5-r-4)

(23)

Wherein 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, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group; A" represents 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, and n 'is an integer of 0 to 2.]

(A2-r-2), (a2-r-3), (a2-r-5) Quot; A " in FIG.

Ra 'group at the ^51, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR'', -OC (= O) R'', hydroxy alkyl, each of the above general formula (a2-r-1) ~ (a2-r-7) are the same as those exemplified in the description of the of the Ra ^'21.

Specific examples of the groups represented by the general formulas (a5-r-1) to (a5-r-4) are described below. "Ac" in the formula represents an acetyl group.

≪ EMI ID =

(25)

(26)

The "carbonate-containing cyclic group" means a cyclic group containing a ring (carbonate ring) containing -O-C (═O) -O- in the cyclic backbone. When the carbonate ring is counted as the first ring, only the carbon ring is monocyclic, and when it has another ring structure, it is called the polycyclic ring regardless of its structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.

The cyclic group containing a carbonate ring is not particularly limited and any cyclic group can be used. Specific examples thereof include groups represented by the following general formulas (ax3-r-1) to (ax3-r-3).

(27)

^Wherein Ra ' ^x31 (= O) R ", a hydroxyalkyl group or a cyano group, R" is a hydrogen atom, an alkyl group, An alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group; A "is an alkylene group, an oxygen atom or a sulfur atom of 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom , p 'is an integer of 0 to 3, and q' is 0 or 1.]

Among the above-mentioned general formulas (ax3-r-1) to (ax3-r-3), A '' is a general formula (a2- Quot; A " in FIG.

Ra 'group at the ^31, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR'', -OC (= O) R'', hydroxy alkyl, each of the above general formula (a2-r-1) ~ (a2-r-7) are the same as those exemplified in the description of the of the Ra ^'21.

Specific examples of the groups represented by the general formulas (ax3-r-1) to (ax3-r-3) are described below.

(28)

As the structural unit (a2), a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent is preferable.

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

[Chemical Formula 29]

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya ²¹ is a single bond or a divalent linking group. La ²¹ represents -O-, -COO-, -CON (R ') -, -OCO-, -CONHCO- or -CONHCS-, and R' represents a hydrogen atom or a methyl group. Provided that when La ²¹ is -O-, then Ya ²¹ is not -CO-. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group or a -SO ₂ -containing cyclic group.]

In the formula (a2-1), R is the same as defined above.

The divalent linking group of Ya ²¹ is not particularly limited, and preferred examples include a divalent hydrocarbon group which may have a substituent, and a divalent linking group including a hetero atom.

A bivalent hydrocarbon group which may have a substituent;

When Ya ²¹ is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

Aliphatic hydrocarbon groups in Ya ²¹

The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually 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.

... .Lectric or branched aliphatic hydrocarbon groups

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -], a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

Aliphatic hydrocarbon group of the branched, and preferably an alkylene group of branched, _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

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 having 1 to 5 carbon atoms substituted with a fluorine atom, and a carbonyl group.

... an aliphatic hydrocarbon group containing a ring in the structure

Examples of the aliphatic hydrocarbon group containing a ring in the structure include a cyclic aliphatic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring) which may contain a substituent group containing a hetero atom in the ring structure, A group in which a hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is introduced in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same ones as described above.

The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the 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 thereof include cyclopentane, cyclohexane, and the like. The polycyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, iso Borane, tricyclodecane, tetracyclododecane and the like.

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, and a carbonyl group.

The alkyl group as the 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.

The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso- propoxy group, a n-butoxy group or a tert- , Ethoxy group is most preferable.

Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

Examples of the halogenated alkyl group as the substituent include groups in which a part or all of the hydrogen atoms of the alkyl group are substituted with the halogen atom.

The cyclic aliphatic hydrocarbon group may be substituted with a substituent group in which a part of carbon atoms constituting the cyclic structure includes a hetero atom. The substituent containing the heteroatom is preferably -O-, -C (= O) -O-, -S-, -S (= O) _2- or -S (= O) ₂ -O- .

The aromatic hydrocarbon group in Ya ²¹

The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.

This aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n + 2 p-electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably from 5 to 30, more preferably from 5 to 20, still more preferably from 6 to 15, and particularly preferably from 6 to 12. Provided that the number of carbon atoms does not include the number of carbon atoms in the substituent. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocyclic rings in which a part of carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.

Specific examples of the aromatic hydrocarbon group include groups in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring (arylene group or heteroarylene group), aromatic compounds containing two or more aromatic rings (for example, A group in which one hydrogen atom of a group (aryl or heteroaryl group) in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocyclic ring is substituted with an alkylene group For example, by further removing one hydrogen atom from an aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, And the like. The number of carbon atoms of the alkylene group bonded to the aryl group or the heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In the aromatic hydrocarbon group, the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.

The alkyl group as the 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.

Examples of the alkoxy group, the halogen atom and the halogenated alkyl group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

A divalent linking group containing a hetero atom:

When Y ^{< a} > is a divalent linking group containing a hetero atom, preferable examples of the linking group include -O-, -C (= O) -O-, -C (= O) -, -C (= O) -NH-, -NH-, -NH-C (= NH) - (H may be substituted with a substituent such as an alkyl group or an acyl group) _{O) 2 -, -S (=} O) 2 -O-, the formula ^{-Y 21 -OY 22 -, -Y 21} -O-, -Y 21 -C (= O) -O-, -C (= ^{O) -OY 21 -, - [} Y 21 -C (= O) -O] m '' -Y 22 -, -Y 21 -OC (= O) -Y 22 - or -Y ²¹ -S (= O ) ₂ -OY ²² - [wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m "is an integer of 0 to 3). ] And the like.

The divalent linking group containing the hetero atom may be -C (= O) -NH-, -C (= O) -NH-C (= O) -, -NH-, -NH-C , The H may be substituted with a substituent such as an alkyl group or an acyl group. The substituent (alkyl group, acyl group, etc.) 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 -OY 22 -, -Y 21} -O-, -Y 21 -C (= O) -O-, -C (= O) -OY 21 -, - [Y 21 -C (= O ^{_{) -O] m '' -Y 22}} -, -Y 21 -OC (= O) -Y 22 - or _{^{-Y 21 -S (= O) 2}} -OY 22 - of, Y ²¹ and Y ²² are each independently And is a divalent hydrocarbon group which may have a substituent. The divalent hydrocarbon group may be the same as the divalent hydrocarbon group which may have a substituent (s) exemplified in the description of the divalent linking group.

Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, particularly preferably a methylene group or an ethylene group.

Y ²² is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.

In the group represented by the formula - [Y ²¹ -C (═O) -O] _{m "} -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, More preferably 1, and particularly preferably 1. That is, the group represented by the formula - [Y ²¹ -C (═O) -O] _{m "} -Y ²² - is particularly preferably a group represented by the formula -Y ²¹ -C (═O) -OY ²² -. Among them, a group represented by the formula - (CH ₂ ) _{a '} -C (═O) -O- (CH ₂ ) _b' - is preferable. 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, 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, more preferably 1 or 2, and most preferably 1.

Ya ²¹ is preferably a single bond, an ester bond [-C (= O) -O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof.

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

The lactone-containing cyclic group, -SO ₂ -containing cyclic group and carbonate cyclic cyclic group in Ra ²¹ are each a group represented by the general formula (a2-r-1) to (a2-r-7) , Groups represented by the general formulas (a5-r-1) to (a5-r-4), and groups represented by the general formulas (ax3-r-1) to (ax3-r-3).

Among them, a lactone-containing cyclic group or -SO ₂ -containing cyclic group is preferable, and a group represented by the general formula (a2-r-1), (a2-r-2) or (a5- desirable. (R-lc-2-1) to (r-lc-2-18), (r-lc-1-7) -1-1) and (r-sl-1-18), respectively.

The constituent unit (a2) of the component (A1) may be one kind or two or more kinds.

When the component (A1) has the structural unit (a2), the proportion of the structural unit (a2) is preferably 1 to 80 mol%, more preferably 10 to 20 mol%, based on the total of all structural units constituting the component (A1) , More preferably 70 mol%, still more preferably 10 mol% to 65 mol%, and particularly preferably 10 mol% to 60 mol%.

When the ratio of the constituent unit (a2) is set to a preferable lower limit value or more, the effect of containing the constituent unit (a2) is sufficiently obtained. On the other hand, when it is not more than the preferable upper limit value, balance with other constituent units can be obtained, The lithography characteristics and the pattern shape are improved.

Constituent unit (a3):

The structural unit (a3) is a structural unit containing a polar group-containing aliphatic hydrocarbon group (except for the structural unit (a0), (a1) or (a2) described above).

When the component (A1) has the structural unit (a3), the hydrophilicity of the component (A) increases, contributing to improvement of the resolution.

Examples of the polar group include a hydroxyl group, a cyano group, a carboxyl group, a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom, and a hydroxyl group is particularly preferable.

Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) or a cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be either a monocyclic group or a polycyclic group. For example, in the resin for a resist composition for an ArF excimer laser, a large number of proposed ones can be appropriately selected and used. The cyclic group is preferably a polycyclic group and more preferably 7 to 30 carbon atoms.

Among them, a structural unit derived from an acrylate ester containing a hydroxyl group, a cyano group, a carboxyl group, or an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of the hydrogen atoms of the alkyl group is substituted with a fluorine atom is more preferable. Examples of the polycyclic group include groups in which two or more hydrogen atoms have been removed from a bicycloalkane, a tricycloalkane, a tetracycloalkane, and the like. Specific examples thereof include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isoborane, tricyclodecane and tetracyclododecane. Among these polycyclic groups, groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane are industrially preferable.

The constituent unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any arbitrary structure can be used.

As the structural unit (a3), a structural unit containing a polar group-containing aliphatic hydrocarbon group as a structural unit derived from an acrylate ester in which a hydrogen atom bonded to a carbon atom at the? -Position may be substituted with a substituent is preferable.

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, the structural unit (a3) is preferably a structural unit derived from a hydroxyethyl ester of acrylic acid, When the hydrocarbon group is a polycyclic group, preferred examples include the structural unit represented by the following formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-3)

(30)

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, 1 is an integer of 1 to 5, s is It is an integer from 1 to 3.]

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

j is preferably 1, and it is particularly preferable that 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-position or the 6-position of the norbornyl group.

In formula (a3-3), t 'is preferably 1. l is preferably 1. s is preferably 1. These are preferably those in which a 2-norbornyl group or a 3-norbornyl group is bonded to the terminal of the carboxyl group of acrylic acid. It is preferable that the fluorinated alkyl alcohol is bonded to the 5th or 6th position of the norbornyl group.

The constituent unit (a3) of the component (A1) may be one kind or two or more kinds.

When the component (A1) has the structural unit (a3), it is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, and most preferably 5 to 10 mol% based on the total amount of all the structural units constituting the component (A1) To 35 mol% is more preferable.

When the ratio of the constituent unit (a3) is set to a preferable lower limit value or more, the effect of containing the constituent unit (a3) is sufficiently obtained. On the other hand, when it is not more than the preferable upper limit value, balance with other constituent units becomes easy.

Constituent unit (a4):

The structural unit (a4) is a structural unit containing an acid-labile aliphatic cyclic group.

When the component (A1) has the structural unit (a4), dry etching resistance of the formed resist pattern is improved. Further, the hydrophobicity of the component (A) is increased. It is considered that the improvement of the hydrophobicity contributes to the improvement of the resolution and the shape of the resist pattern in the case of the solvent developing process in particular.

The "acid-labile cyclic group" in the constituent unit (a4) is preferably an acid labile cyclic group when the acid is generated in the resist composition by exposure (for example, when an acid is generated from the component (B) Is a cyclic group remaining in the constituent unit as it is without dissociating.

As the constituent unit (a4), for example, a constituent unit derived from an acrylate ester containing an aliphatic cyclic group having acidity is preferable. The cyclic group is used for a resin component of a resist composition such as an ArF excimer laser or a KrF excimer laser (preferably for an ArF excimer laser), and many conventionally known ones can be used.

Particularly, at least one member 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.

Specific examples of the structural unit (a4) include structural units represented by the following general formulas (a4-1) to (a4-7).

(31)

[Wherein R ^? Is as defined above].

The constituent unit (a4) of the component (A1) may be one kind or two or more kinds.

When the component (A1) has the structural unit (a4), the proportion of the structural unit (a4) is preferably from 1 to 30 mol%, more preferably from 3 to 30 mol%, based on the total structural units constituting the component (A1) More preferably 20 mol%.

When the ratio of the constituent unit (a4) is set to a preferable lower limit value or more, the effect of containing the constituent unit (a4) is sufficiently obtained. On the other hand, when it is not more than the preferable upper limit value, balance with other constituent units becomes easy.

In the resist composition of the present embodiment, the component (A) includes the polymer compound (A1) having the constituent unit (a0), and specifically the constituent unit (a0) a1) and a repeating structure of the constituent unit (a2).

The mass average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography (GPC)) of the component (A1) is not particularly limited and is preferably from 1,000 to 50,000, more preferably from 1,500 to 30,000, 20000 is most preferable.

If the Mw of the component (A1) is not higher than the upper limit of the preferable range, there is sufficient solubility in a resist solvent for use as a resist, and if it is not lower than the lower limit of the above range, the dry etching resistance and the cross- .

The dispersion degree (Mw / Mn) of the component (A1) is not particularly limited and is preferably 1.0 to 5.0, more preferably 1.0 to 4.0, and most preferably 1.0 to 3.0. Mn represents the number average molecular weight.

The component (A1) may be used alone or in combination of two or more.

The proportion of the component (A1) in the component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, further preferably 75% by mass or more, Mass%. If the ratio is 25 mass% or more, a resist pattern having excellent lithography properties such as high sensitivity and roughness improvement is likely to be formed.

The resist composition of the present embodiment comprises a base component (hereinafter referred to as "component (A2)") which does not correspond to the component (A1) and whose solubility in a developing solution changes by the action of an acid Or may be used in combination.

(A2) is not particularly limited, and a large number of conventionally known base components for chemically amplified resist compositions (for example, for ArF excimer laser, KrF excimer laser (preferably for ArF excimer laser) And the like). The component (A2) may be used alone or in combination of two or more.

In the resist composition of the present embodiment, the component (A) may be used alone or in combination of two or more.

The content of the component (A) in the resist composition of the present embodiment may be adjusted depending on the thickness of the resist film to be formed.

≪ Component (B) >

Component (B) is an acid generator component which generates an acid upon exposure.

[Component (B1)] [

The component (B) used in the resist composition of the present embodiment includes the acid generator (B1) (hereinafter referred to as "component (B1)") composed of the compound represented by the general formula (b1).

(32)

Wherein R ¹⁰¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. q " is an integer of 1 to 20; m is an integer of 1 or more, and M ^{m +} is an organic cation of m.

The anion portion of the component (B1)

In the formula (b1), R ¹⁰¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.

A 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 aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually saturated.

The aromatic hydrocarbon group in R < ¹⁰¹ > is a hydrocarbon group having an aromatic ring. The number of carbon atoms of the aromatic hydrocarbon group is preferably from 3 to 30, more preferably from 5 to 30, still more preferably from 5 to 20, particularly preferably from 6 to 15, most preferably from 6 to 10. Provided that the number of carbon atoms does not include the number of carbon atoms in the substituent.

Specific examples of the aromatic ring of the aromatic hydrocarbon group in R ¹⁰¹ include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, aromatic heterocyclic rings in which a part of carbon atoms constituting aromatic rings thereof are substituted with a hetero atom Rings and the like. Examples of the heteroatom in the aromatic heterocyclic ring include an oxygen atom, a sulfur atom and a nitrogen atom.

Specific examples of the aromatic hydrocarbon group for R ¹⁰¹ include groups in which one hydrogen atom has been removed from the aromatic ring (aryl group: for example, phenyl group, naphthyl group, etc.) (For example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group and the like) and the like. The number of carbon atoms of the alkylene group (alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The cyclic aliphatic hydrocarbon group for R ¹⁰¹ includes an aliphatic hydrocarbon group containing a ring in its structure.

As the aliphatic hydrocarbon group containing a ring in this structure, an alicyclic hydrocarbon group (a group obtained by removing one hydrogen atom from an aliphatic hydrocarbon ring), a group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group , And groups in which an alicyclic hydrocarbon group is introduced in the midst of a linear or branched aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms.

The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing at least one hydrogen atom from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and the like. The polycyclic alicyclic hydrocarbon group is preferably a group in which at least one hydrogen atom is removed from the polycycloalkane. The polycycloalkane preferably has 7 to 12 carbon atoms, and specifically includes adamantane, norbornane, Isobornane, tricyclodecane, tetracyclododecane, and the like.

Among them, the cyclic aliphatic hydrocarbon group for R ¹⁰¹ is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane or a polycycloalkane, more preferably a group obtained by removing one hydrogen atom from a polycycloalkane, An adamantyl group and a norbornyl group are particularly preferable, and an adamantyl group is most preferable.

The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, further preferably 1 to 4, and most preferably 1 to 3 desirable.

As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [- (CH ₂ ) ₂ -], a trimethylene group [- CH ₂ ) ₃ -], tetramethylene group [- (CH ₂ ) ₄ -], pentamethylene group [- (CH ₂ ) ₅ -] and the like.

Aliphatic hydrocarbon group of the branched, and preferably an alkylene group of branched, _{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 - a methylene group, such as alkyl; -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 -; alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ -, and the like; -CH (CH ₃ ) CH ₂ CH _And alkyltetramethylene groups such as ₂ CH ₂ -, -CH ₂ CH (CH ₃ ) CH ₂ CH ₂ -, and the like. The alkyl group in the alkyl alkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

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 (-C (= O) -) An ester bond (-C (= O) -O-), and a nitro group.

As the alkyl group as a substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are more preferable.

The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, , Ethoxy group is most preferable.

Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

Examples of the halogenated alkyl group as a substituent include an alkyl group having 1 to 5 carbon atoms such as a group in which a part or all of hydrogen atoms such as methyl, ethyl, propyl, n-butyl and tert- have.

The carbonyl group (-C (= O) -), the ether bond (-O-) and the ester bond (-C (= O) -O-) as a substituent may be a methylene group (-CH ₂ - ).

Examples of the cyclic hydrocarbon group for R < ¹⁰¹ > include the following "aliphatic hydrocarbon group having a substituent including a ring in the structure".

(33)

The cyclic hydrocarbon group in R ¹⁰¹ may include a hetero atom such as a heterocyclic ring. Specifically, a lactone-containing cyclic group represented by any one of the above-mentioned general formulas (a2-r-1) to (a2-r-7) -SO ₂ -containing cyclic group, and other heterocyclic groups exemplified below.

(34)

Chain alkyl group which may have a substituent:

The chain alkyl group represented by R < ¹⁰¹ > may be either 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. Specific examples thereof include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, , A tetradecyl group, a pentadecyl group, a hexadecyl group, an isohexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an eicosyl group, a heneicosyl group and a docosyl group.

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. Specific examples thereof include 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, -Ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group and 4-methylpentyl group.

Chain alkenyl group which may have a substituent:

The chain-like alkenyl group of R < ¹⁰¹ > may be either linear or branched, preferably has 2 to 10 carbon atoms, more preferably 2 to 5, still more preferably 2 to 4, 3 is particularly preferable. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), and a butyryl group. Examples of the branched-chain alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group and a 2-methylpropenyl group.

As the chain-like alkenyl group, a vinyl group or a propenyl group is more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chain type alkyl group or alkenyl group of R ¹⁰¹ include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group (-C (= O) -) , An ester bond (-C (= O) -O-), a nitro group, an amino group, and a cyclic group in the above R ¹⁰¹ .

The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, , Ethoxy group is most preferable.

Examples of the halogen atom as a substituent include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

Examples of the halogenated alkyl group as a substituent include an alkyl group having 1 to 5 carbon atoms such as a group in which a part or all of hydrogen atoms such as methyl, ethyl, propyl, n-butyl and tert- have.

The carbonyl group (-C (= O) -), the ether bond (-O-) and the ester bond (-C (= O) -O-) as a substituent may be a methylene group (- CH ₂ -).

Among them, R ¹⁰¹ is preferably a cyclic group which may have a substituent, more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, groups in which one or more hydrogen atoms have been removed from a phenyl group which may have a substituent, a naphthyl group which may have a substituent, or a polycycloalkane which may have a substituent; groups represented by the above formulas (a2-r-1) to lactone showing respectively -r-7) containing cyclic group, the formula (a5-r-1) ~ (-SO 2 represent respectively a5-r-4) - containing cyclic group and the like.

In the formula (b1), q '' is an integer of 1 to 20, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, still more preferably an integer of 1 to 3, Particularly preferably 1.

Preferred examples of the anion of the component (B1) are shown below.

(35)

Cation part of the component (B1):

In the formula (b1), M ^{m +} is an organic cation of m valence, and is preferably an onium cation, and specifically, sulfonium cation, iodonium cation and the like are preferable.

The cation moiety [(M ^{m +} ) _{1 / m} ] of the component (B1) is preferably an organic cation represented by the following general formulas (ca-1) to (ca-4).

(36)

[Wherein, R ²⁰¹ ~ R ^207, and R ²¹¹ ~ R ²¹² each independently represents an aryl group, an alkyl group or an alkenyl group which may have a ^{substituent, R 201 ~ R 203, R} 206 ~ R 207, R 211 ~ And R ²¹² may bond together to form a ring with the sulfur atom in the formula. R ²⁰⁸ ~ R ²⁰⁹ each independently represents a hydrogen atom or an alkyl group having a carbon number of 1 ~ 5, R ²¹⁰ is an aryl group, an alkyl group, an alkenyl group, or -SO ₂ which may contain a substituent group-containing a cyclic group, L ²⁰¹ is -C (= O) - or -C (= O) represents a -O-, Y ²⁰¹ are each independently an arylene group, an alkylene group, or represents an alkenylene group, x is 1 or 2, W ²⁰¹ is (x + 1 ) Represents a connecting group.

As the aryl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² , an unsubstituted aryl group having 6 to 20 carbon atoms is exemplified, and a phenyl group or a naphthyl group is preferable.

The alkyl group in R ²⁰¹ ~ R ²⁰⁷ and R ²¹¹ ~ R ²¹² is a chain-like or cyclic alkyl group, preferably of 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, To (ca-r-7), respectively.

(37)

: Wherein R ' ²⁰¹ each independently represents a hydrogen atom, a cyclic group which may have a substituent, a chain-like alkyl group or a chain-like alkenyl group.

The cyclic group which may have a substituent of R ' ²⁰¹ , the chain alkyl group which may have a substituent, or the chain-like alkenyl group which may have a substituent may be the same as R ¹⁰¹ in the above-mentioned formula (b1) In addition to the above, the cyclic group which may have a substituent or the chain-like alkyl group which may have a substituent may be the same as the acid dissociable group represented by the above-mentioned formula (a1-r-2).

R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ and R ²¹¹ to R ²¹² may form a ring with the sulfur atom in the formula to form a ring, a hetero atom such as a sulfur atom, an oxygen atom or a nitrogen atom, May be bonded through functional groups such as SO-, -SO ₂ -, -SO _{3 -} , -COO-, -CONH- or -N (R _N ) - (R _N is an alkyl group having 1 to 5 carbon atoms). As the ring to be formed, one ring containing a sulfur atom in the formula in its ring skeleton is preferably 3 to 10 atomic rings including a sulfur atom, and it is particularly preferable that it is a 5 to 7-membered ring. Specific examples of the ring to be formed include, for example, thiophene ring, thiazole ring, benzothiophene ring, thianthrene ring, benzothiophene ring, dibenzothiophene ring, 9H-thiosanthene ring, thiosantone ring, A thianthrene ring, a phenoxathiine ring, a tetrahydrothiophenium ring, a tetrahydrothiopyranium ring and the like.

Each of R ²⁰⁸ to R ²⁰⁹ independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. When the alkyl group is an alkyl group, they may be bonded to each other to form a ring.

R ²¹⁰ is an optionally substituted aryl group, optionally substituted alkyl, optionally substituted alkenyl, or optionally substituted -SO ₂ - containing cyclic group.

As the aryl group in R ²¹⁰ , an unsubstituted aryl group having 6 to 20 carbon atoms can be mentioned, and a phenyl group and a naphthyl group are preferable.

The alkyl group in R ²¹⁰ is preferably a chain 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 includes the same ones as the "-SO ₂ -containing cyclic group" of Ra ^{21 in} the above-mentioned general formula (a2-1) The group represented by the above-mentioned general formula (a5-r-1) is preferable.

Y ²⁰¹ each independently represent an arylene group, an alkylene group or an alkenylene group.

The arylene group for Y ²⁰¹ includes a group obtained by removing one hydrogen atom from the aryl group exemplified as the aromatic hydrocarbon group in R ¹⁰¹ in the above-mentioned formula (b1).

The alkylene group and alkenylene group in Y ²⁰¹ are the same as the aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ⁰ in the general formula (a0-1) described above.

In the formula (ca-4), x is 1 or 2.

W ²⁰¹ is (x + 1), that is, a divalent or trivalent linking group.

As the divalent linking group for W ²⁰¹ , a divalent hydrocarbon group which may have a substituent is preferable, and the same hydrocarbon group as Ya ²¹ in the general formula (a2-1) described above can be exemplified. The bivalent linking group in W ²⁰¹ may be any of linear, branched, and 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. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferable.

Connection of the trivalent group is ²⁰¹ W, and ²⁰¹ W the group 1 to remove the hydrogen atom from the divalent linking group in, in addition to the divalent linking group, and the like which combines the divalent connecting group. As the trivalent linking group in W ²⁰¹ , a group in which two carbonyl groups are bonded to an arylene group is preferable.

Specific examples of preferred cation represented by the formula (ca-1) include the cations represented by the following formulas (ca-1-1) to (ca-1-67).

(38)

[Chemical Formula 39]

(40)

G1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20.] [wherein g1, g2 and g3 are repeating numbers, g1 is an integer of 1 to 5, g2 is an integer of 0 to 20,

(41)

Wherein R ²⁰¹ is a hydrogen atom or a substituent and the substituents are the same as those exemplified as the substituent which R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have.

Specific examples of preferable cation represented by the above formula (ca-2) include diphenyliodonium cationide and bis (4-tert-butylphenyl) iodonium cationide.

Specific examples of the preferred cation represented by the above formula (ca-3) include the cations represented by the following formulas (ca-3-1) to (ca-3-6)

(42)

Specific examples of the preferred cation represented by the above formula (ca-4) include the cation represented by the following formulas (ca-4-1) to (ca-4-2).

(43)

Among the above, a cation moiety _{^{[(M 'm +) 1}} / m] Is preferably an organic cation represented by the formula (ca-1), more preferably a cation represented by the formula (ca-1-1) to (ca-1-67).

As the component (B1), the acid generators described above may be used singly or in combination of two or more.

In the resist composition of the present embodiment, the content of the component (B1) is preferably from 1 to 30 parts by mass, more preferably from 2 to 20 parts by mass, and still more preferably from 2 to 15 parts by mass, per 100 parts by mass of the component (A).

When the content of the component (B1) is a preferable lower limit value or more, lithographic characteristics such as roughness reduction are further improved when the resist composition is used. In addition, a resist pattern of good shape can be easily obtained. If the content of the component (B1) is not more than the preferable upper limit value, a homogeneous solution can be obtained and storage stability is improved.

The proportion of the component (B1) in the component (B) is preferably 2% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, By mass or more, particularly preferably 100% by mass or more. Most preferably 100% by mass. When the ratio of the component (B1) in the component (B) is a preferable lower limit value or more, the resist composition is more likely to reduce roughness, and a resist pattern with better lithography characteristics is formed.

[Component (B2)] [

The component (B) may contain an acid generator component (hereinafter referred to as "component (B2)") which generates an acid by exposure other than the component (B1).

The component (B2) is not particularly limited, and those proposed as acid generators for chemically amplified resists can be used.

Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisaryl sulfonyl diazomethanes, poly (bis-sulfonyl) diazomethane Diazomethane-based acid generators such as diethyleneglycol-based diazomethane-based acid generators, nitrobenzylsulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators. Among them, it is preferable to use an onium salt-based acid generator.

Examples of the onium salt-based acid generators include compounds represented by the following general formula (b-1) (hereinafter also referred to as "component (b-1) (Hereinafter also referred to as "component (b-2)"), or a compound represented by general formula (b-3)

(44)

^Wherein R ¹⁰³ and R ¹⁰⁴ to R ¹⁰⁸ are each independently a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ may combine with each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 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 are each independently 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. L ¹⁰³ to L ¹⁰⁵ each independently represent a single bond, -CO- or -SO ₂ -. m is an integer of 1 or more, and M ' ^{m +} is an m-valent onium cation.

{NO ONE}

The anion of component (b-1)

In the formula (b-1), R ¹⁰³ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.

Examples of such R ¹⁰³ include a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, which are the same as R ¹⁰¹ in the formula (b1) ≪ / RTI >

Among them, R ¹⁰³ is preferably a cyclic group which may have a substituent, more preferably a cyclic hydrocarbon group which may have a substituent. (A2-r-1) to (a2-r-7), a cyclic group containing a lactone having the above general formula And -SO ₂ -containing cyclic groups represented by formulas (a5-r-1) to (a5-r-4), respectively.

In the formula (b-1), Y ¹⁰¹ is a divalent linking group containing a single bond or an oxygen atom.

¹⁰¹ If Y is a divalent connecting group containing an oxygen atom, and Y ¹⁰¹ is may contain atoms other than oxygen atoms. Examples of the atom other than the oxygen atom include a carbon atom, a hydrogen atom, a sulfur atom, and a nitrogen atom.

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 (-OC Hydrocarbon group-containing oxygen atom-containing linking groups such as an amide bond (-C (= O) -NH-), a carbonyl group (-C (= O) -) ; A combination of a non-hydrocarbon-based oxygen atom-containing linking group and an alkylene group; and the like. The combination may further include a sulfonyl group (-SO ₂ -). Examples of such a combination include linking groups represented by the following formulas (y-al-1) to (y-al-7).

[Chemical Formula 45]

Wherein V ' ¹⁰¹ is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.

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 chain alkylene group, preferably a linear alkylene group.

V as an alkylene group in the ^"101 and V" ^102, specifically, a methylene group _{[-CH 2 -]; - CH} (CH 3) -, -CH (CH 2 CH 3) -, -C (CH 3) _{2 -, -C (CH 3)} (CH 2 CH 3) -, -C (CH 3) (CH 2 CH 2 CH 3) -, -C (CH 2 CH 3) 2 - a methylene group of the alkyl and the like; ethylene group _{[-CH 2 CH 2 -];} - CH (CH 3) CH 2 -, -CH (CH 3) CH (CH 3) -, -C (CH 3) 2 CH 2 -, -CH (CH 2 CH ₃₎ CH ₂ - alkyl group such as ethylene; trimethylene group (n- propylene _{group) [-CH 2 CH 2 CH 2} -]; - CH (CH 3) CH 2 CH 2 -, -CH 2 CH (CH 3 ) CH ₂ - alkyl trimethylene group and the like; a tetramethylene group _{[-CH 2 CH 2 CH 2 CH} 2 -]; - CH (CH 3) CH 2 CH 2 CH 2 -, -CH 2 CH (CH 3) CH ₂ CH ₂ -, etc .; pentamethylene group [-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -] and the like.

In addition, some of the methylene groups in the alkylene group in V ' ¹⁰¹ or V' ¹⁰² may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably a monovalent group or a bivalent group obtained by further removing one hydrogen atom from an aliphatic hydrocarbon group which is a polycyclic group in Ra ' ³ in the formula (a1-r-1), and cyclohexylene More preferably a 1,5-adamantylene group or a 2,6-adamantylene group.

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

In the formula (b-1), V ¹⁰¹ is a single bond, an alkylene group or a fluorinated alkylene group. The alkylene group and fluorinated alkylene group in V ¹⁰¹ preferably have 1 to 4 carbon atoms. A fluorinated alkylene group in the V ¹⁰¹ is, a part or all of the hydrogen atoms of the alkylene group of the ¹⁰¹ V may be 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 the 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, more preferably a fluorine atom.

Specific examples of the anion moiety of component (b-1) include, for example, when Y ¹⁰¹ is a single bond, fluorinated alkylsulfone such as trifluoromethanesulfonate anion or perfluorobutanesulfonate anion When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, an anion represented by the following formula (an-1) (provided that v "= 0, n" = 0, t (Except for the case where '' = 1), anion represented by the formula (an-2) and anion represented by the formula (an-3).

(46)

: Wherein R ¹⁰¹ is an aliphatic cyclic group which may have a substituent, a group respectively represented by the above formulas (r-hr-1) to (r-hr-6) R ¹⁰² represents an aliphatic cyclic group which may have a substituent, a lactone-containing cyclic group represented by the above formulas (a2-r-1) to (a2-r-7) r-1) ~ (a5- r-4) -SO 2 represent respectively-containing cyclic group and; r '' ¹⁰³ is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent And q '' each independently represents an integer of 1 to 20, and t '' represents an integer of 1 to 3, n "is 0 or 1.]

The aliphatic cyclic group which may have a substituent group for R " ¹⁰¹ , R" ¹⁰² and R " ¹⁰³ is preferably a group exemplified as the cyclic aliphatic hydrocarbon group for R ¹⁰¹ in the formula (b1). The substituent may be the same as the substituent which may be substituted with the cyclic aliphatic hydrocarbon group in R ¹⁰¹ .

The aromatic cyclic group which may have a substituent in R " ¹⁰³ is preferably a group exemplified as an aromatic hydrocarbon group in the cyclic hydrocarbon group for R ¹⁰¹ . Examples of the substituent include the same substituent as the substituent that the aromatic hydrocarbon group in R ¹⁰¹ may be substituted.

The chain-like alkyl group which may have a substituent in R " ¹⁰¹ is preferably a group exemplified as a chain-like alkyl group in R < ^{101 &} gt ;. The chain type alkenyl group which may have a substituent in R " ¹⁰³ is preferably a group exemplified as a chain type alkenyl group in R ¹⁰¹ .

The anion of component (b-2)

In formula (b-2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, , And the same as R ¹⁰¹ in the formula (b1). However, R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring.

R ¹⁰⁴ and R ¹⁰⁵ are preferably a chain-like alkyl group which may have a substituent, more preferably a linear or branched alkyl group, or a linear or branched alkyl group.

The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and still more preferably 1 to 3 carbon atoms. The number of carbon atoms of the chain-like alkyl group represented by R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible within the above range of the number of carbon atoms and solubility in a resist solvent. In the chain alkyl group of R ¹⁰⁴ and R ^105, the more the number of hydrogen atoms substituted with fluorine atoms is, the stronger the strength of the acid is, and the higher the transparency to the high energy light of 200 nm or less and the electron beam . The ratio of the fluorine atoms in the chain alkyl group, that is, the fluoride group is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all the hydrogen atoms are fluorine-substituted perfluoroalkyl groups.

In the formula (b-2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group, and the same groups as those of V ¹⁰¹ in the formula (b-1)

In the formula (b-2), L ¹⁰¹ to L ¹⁰² each independently represent a single bond or an oxygen atom.

The anion of component (b-3)

In formula (b-3), each of R ¹⁰⁶ to R ¹⁰⁸ independently represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, , And the same as R ¹⁰¹ in the formula (b1).

L ¹⁰³ to L ¹⁰⁵ each independently represent a single bond, -CO- or -SO ₂ -.

{Kationbu}

Formula (b-1), (b -2) and (b-3) of the, M ^{'m +} may be preferably an m-valent cation is an onium, sulfonium cation, iodonium cation. ( ^{M'm +} ₁ ) _{/ m} , specifically, the same organic cations represented by the above general formulas (ca-1) to (ca-4) (Ca-3-1) to (ca-3-i) represented by the above formulas (ca- (Ca-4-1) to (Ca-4-2), respectively.

Among the above, a cation moiety _{^{[(M 'm +) 1}} / m] is preferably the following general formula the organic cation represented by (ca-1) and formula (ca-1-1) ~ (ca -1-67) Are more preferable.

As the component (B), the above-mentioned acid generators may be used singly or in combination of two or more.

When the resist composition of the present embodiment contains the component (B2), the content of the component (B2) is preferably 30 parts by mass or less, more preferably 0.5 to 20 parts by mass, and most preferably 0.5 To 15 parts by mass is more preferable.

By setting the content of the component (B2) within the above-described preferable range, pattern formation is sufficiently performed. Further, when each component of the resist composition is dissolved in an organic solvent, a homogeneous solution can be obtained and storage stability is improved, which is preferable.

≪ Other components >

[Component (D)] [

The resist composition of the present embodiment may further contain an acid diffusion controller component (hereinafter referred to as "component (D)") in addition to the above components (A) and (B).

The component (D) acts as a quencher (acid diffusion control agent) for trapping an acid generated by exposure from the component (B) or the like.

Examples of the component (D) include a photo-degradable base (D1) (hereinafter, referred to as a "component (D1)") which is decomposed by exposure to lose acid diffusion controllability (Hereinafter referred to as " component (D2) ") which does not correspond to the nitrogen-containing organic compound (D2).

(With respect to the component (D1)),

(D1), the contrast between the exposed portion and the unexposed portion can be improved when the resist pattern is formed.

The component (D1) is not particularly limited as long as it is decomposed by exposure to lose acid diffusion controllability, and the compound represented by the following general formula (d1-1) (hereinafter referred to as the "component (d1-1) (Hereinafter referred to as " component (d1-3) ") and a compound represented by the following general formula (d1-3) ) Is preferable.

The components (d1-1) to (d1-3) do not act as a quencher because they dissolve in the exposed portion and lose acid diffusion controllability (basicity), and act as a quencher in the unexposed portion.

(47)

[Wherein, Rd Rd ¹ ~ ⁴ is cyclic group which may have a substituent, an alkenyl group which may contain a chain-like alkyl group, or a substituent of the type chain which may have a substituent. It is to be noted that the 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 is an integer of 1 or more, and M ^< ^{m +} & ^{gt ;} are each independently an m-valent organic cation.

(D1-1) Component

(d1-1) Component of anion:

Formula (d1-1) of, R ^{1 101} of Rd is an alkenyl group of chain which may contain a cyclic group, an alkyl group of chain which may have a substituent, or a substituent which may have a substituent, the formula (b1) And the like.

Among them, Rd ¹ is preferably an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain-like alkyl group which may have a substituent. As the substituent which these groups may have, a hydroxyl group, a fluorine atom or a fluorinated alkyl group is preferable.

As the aromatic hydrocarbon group, a phenyl group or a naphthyl group is more preferable.

The aliphatic cyclic group is more preferably a group obtained by removing at least one hydrogen atom from a polycycloalkane such as adamantane, norbornane, isoborane, tricyclodecane, or tetracyclododecane.

The chain type alkyl group preferably has 1 to 10 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, Methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2- Ethylhexyl group, ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group and 4-methylpentyl group.

When the above chain alkyl group is a fluorinated alkyl group having a fluorine atom as a substituent, the number of carbon atoms of the fluorinated alkyl group is preferably from 1 to 11, more preferably from 1 to 8, still more preferably from 1 to 4. The fluorinated alkyl group may contain an atom other than a fluorine atom. Examples of the atom other than the fluorine atom include an oxygen atom, a carbon atom, a hydrogen atom, a sulfur atom, and a nitrogen atom.

As Rd ¹ , it is preferable that some or all of hydrogen atoms constituting the linear alkyl group are fluorinated alkyl groups substituted by fluorine atoms, and fluorinated alkyl groups in which all the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms A linear perfluoroalkyl group).

Preferred examples of the anion moiety of the component (d1-1) are shown below.

(48)

(d1-1) Cation part of the component:

In the formula (d1-1), M ^{m +} is an organic cation of m.

The organic cation of M ^{m +} is preferably the same as the cation represented by the above general formulas (ca-1) to (ca-4), and the cation represented by the general formula (ca- And the cation represented by the above formulas (ca-1-1) to (ca-1-67) are more specific.

 The component (d1-1) may be used singly or in combination of two or more.

(D1-2) Component

(d1-2) Component of anion:

Formula (d1-2) of from, Rd ^2, the cyclic group which may have a substituent, an alkenyl group which may contain a chain-like alkyl chain which may have a substituent, or a substituent of Formula (b1) R ¹⁰¹ < / RTI >

It is to be noted that the carbon atom adjacent to the S atom in Rd ² is not bonded to the fluorine atom (it is not fluorine-substituted). As a result, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the quenching ability as the component (D) improves.

Rd ² is preferably an aliphatic cyclic group which may have a substituent, and a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. More preferably a group obtained by removing one or more hydrogen atoms from a camphor or the like.

The hydrocarbon group of Rd ² may have a substituent and the substituent is the same as the substituent which the hydrocarbon group (aromatic hydrocarbon group, aliphatic hydrocarbon group) in Rd ¹ of the formula (d1-1) may have. have.

Preferred examples of the anion moiety of the component (d1-2) are shown below.

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(d1-2) Cation part of the component:

In the formula (d1-2), M ^{m +} is an organic cation of ^m and is the same as M ^{m +} in the formula (d1-1).

(d1-2) may be used singly or in combination of two or more.

(D1-3) Component

(d1-3) Component of anion:

Formula (d1-3) of, Rd ³ is R ¹⁰¹ in the cyclic group which may have a substituent, an alkyl chain which may have a substituent, or an alkenyl group of chain which may have a substituent, the formula (b1) , And it is preferably a cyclic group containing a fluorine atom, a chain-like alkyl group, or a chain-like alkenyl group. Among them, a fluorinated alkyl group is preferable, and the same as the fluorinated alkyl group of Rd ¹ is more preferable.

Formula (d1-3) of, Rd ⁴ is cyclic group which may have a substituent, an alkyl chain which may have a substituent, or an alkenyl group of chain which may have a substituent, R in the formula (b1) ¹⁰¹ < / RTI >

Among them, an alkyl group, alkoxy group, alkenyl group and cyclic group which may have a substituent are preferable.

The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms and specifically includes a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Part of the hydrogen atoms of the alkyl group Rd is ⁴ may be substituted by 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 specifically, an alkoxy group having 1 to 5 carbon atoms such as methoxy, ethoxy, n-propoxy, iso- Butoxy group, and tert-butoxy group. Among them, a methoxy group and an ethoxy group are preferable.

The alkenyl group in Rd ⁴ may be the same as R ¹⁰¹ in the above formula (b1), preferably a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group or a 2-methylpropenyl group. These groups may further have, as a substituent, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

The cyclic group in Rd ⁴ includes the same groups as R ¹⁰¹ in the above formula (b1), and examples thereof include cyclopentane, cyclohexane, adamantane, norbornane, isoborane, tricyclodecane, tetracyclododecane Or an aromatic group such as a phenyl group or a naphthyl group is preferable. When Rd ⁴ is an alicyclic group, the resist composition is well dissolved in the organic solvent, and the lithography characteristics are improved. When Rd ⁴ is an aromatic group, in the case of lithography using EUV as an exposure light source, the resist composition is excellent in light absorption efficiency, and has good sensitivity and lithography characteristics.

Formula (d1-3) of, Yd ¹ is a single bond or a divalent connecting group.

The divalent linking group in Yd ¹ includes, but is not limited to, a divalent hydrocarbon group (aliphatic hydrocarbon group or aromatic hydrocarbon group) which may have a substituent, and a divalent linking group containing a hetero atom. These may be the same as the divalent linking group containing a divalent hydrocarbon group or a hetero atom which may have a substituent, which is exemplified in the explanation of the divalent linking group of Ya ²¹ in the formula (a2-1) .

Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, more preferably a methylene group or an ethylene group.

Preferred examples of the anion moiety of the component (d1-3) are shown below.

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(d1-3) Cation part of the component:

In the formula (d1-3), M ^{m +} is an organic cation of ^m and is the same as M ^{m +} in the formula (d1-1).

(d1-3) may be used singly or in combination of two or more.

As the component (D1), any one of the components (d1-1) to (d1-3) may be used, or two or more components 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, and further preferably 1 to 8 parts by mass with respect to 100 parts by mass of the component (A).

When the content of the component (D1) is a preferable lower limit value or more, particularly good lithography characteristics and resist pattern shapes are obtained. On the other hand, if it is not more than the preferable upper limit value, the sensitivity can be kept good and the throughput is also excellent.

Method for producing component (D1)

The method for producing the above components (d1-1) and (d1-2) is not particularly limited and can be produced by a known method.

The method for producing the component (d1-3) is not particularly limited, and is produced in the same manner as described in, for example, US2012-0149916.

(With respect to the component (D2)),

As the acid diffusion control agent component, a nitrogen-containing organic compound component (hereinafter referred to as "(D2) component") which does not correspond to the above-mentioned component (D1) may be used.

The component (D2) is not particularly limited as long as it functions as an acid diffusion control agent and does not correspond to the component (D1), and any known component may be used. Of these, aliphatic amines, especially secondary aliphatic amines and tertiary aliphatic amines, are preferred.

The aliphatic amine is an amine having at least one aliphatic group, and the aliphatic group preferably has 1 to 12 carbon atoms.

Examples of the aliphatic amine include an amine (alkylamine or alkyl alcohol amine) in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or a hydroxyalkyl group having 12 or less carbon atoms, or a cyclic amine.

Specific examples of alkylamines and alkylalcoholamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine and n-decylamine; Dialkylamines such as propylamine, di-n-heptylamine, di-n-octylamine and dicyclohexylamine; aliphatic amines such as trimethylamine, triethylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, Alkylamine, alkyl alcohol amine such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, tri-n-octanolamine and the like. Of these, trialkylamines having 5 to 10 carbon atoms are more preferred, and tri-n-pentylamine or tri-n-octylamine is particularly preferred.

The cyclic amine includes, for example, a heterocyclic compound containing a nitrogen atom as a hetero atom. The heterocyclic compound may be a monocyclic (aliphatic monocyclic) amine or a polycyclic (aliphatic polycyclic) amine.

Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.

As the aliphatic polycyclic amines, the number of carbon atoms is preferably from 6 to 10. Specific examples thereof include 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-ethoxypropoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} , Tris [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] amine, triethanolamine triacetate and the like, and triethanolamine triacetate is preferable.

As the component (D2), an aromatic amine may be used.

Examples of the aromatic amine include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxycarbonylpyrrolidine .

(D2) may be used alone or in combination of two or more.

(D2) is usually used in a range of 0.01 to 5 parts by mass based on 100 parts by mass of the component (A). By setting the resistivity to the above range, the resist pattern shape, time-course stability after exposure, and the like are improved.

When the resist composition of the present embodiment contains the component (D), it preferably contains the photodegradable base (D1) which is decomposed by exposure and loses acid diffusion controllability, and the component (d1-2) Or more.

[Component (E)] [

The resist composition of the present invention may contain, as an optional component, an organic carboxylic acid, and a group of phosphoric oxo acid and derivatives thereof for the purpose of preventing deterioration of sensitivity, improving the resist pattern shape and time- At least one selected compound (E) (hereinafter referred to as "component (E)") may 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 the phosphoric acid include phosphoric acid, phosphonic acid and phosphinic acid, and phosphonic acid is particularly preferable.

Examples of the derivative of the phosphorous oxo acid include an ester in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group. Examples of the hydrocarbon group include an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 15 carbon atoms .

Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.

Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester and phosphonic acid dibenzyl ester.

Examples of derivatives of phosphinic acid include phosphinic acid esters and phenylphosphinic acid.

The component (E) may be used alone or in combination of two or more.

The component (E) is usually used in a range of 0.01 to 5 parts by mass based on 100 parts by mass of the component (A).

[Component (F)] [

The resist composition of the present embodiment may contain a fluorine additive (hereinafter referred to as "component (F)") for imparting water repellency to the resist film.

Examples of the component (F) include, for example, those described in JP-A No. 2010-002870, JP-A No. 2010-032994, JP-A No. 2010-277043, JP-A No. 2011-13569, The fluorinated polymer compound described in the publication No. 2011-128226 can be used.

More specifically, as the component (F), a polymer having a structural unit (f1) represented by the following formula (f1-1) may be mentioned. Examples of the polymer include a polymer (homopolymer) comprising only the constituent unit (f1) represented by the following formula (f1-1), a copolymer of the constituent unit (f1) and the constituent unit (a1) , A structural unit derived from acrylic acid or methacrylic acid, and a copolymer of the structural unit (a1). Here, as the structural unit (a1) copolymerized with the structural unit (f1), a structural unit derived from 1-ethyl-1-cyclooctyl (meth) acrylate is preferable.

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Rf ¹⁰² and Rf ¹⁰³ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf ¹⁰² and Rf ¹⁰³ may be the same or different, They 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 bonded to the carbon atom at the? -Position is the same as described above. As R, a hydrogen atom or a methyl group is preferable.

In the formula (f1-1), examples of the halogen atom of Rf ¹⁰² and Rf ¹⁰³ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable. Examples of the alkyl group having 1 to 5 carbon atoms represented by Rf ¹⁰² and Rf ^{103 include} the same alkyl groups having 1 to 5 carbon atoms as R described above, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms represented by Rf ¹⁰² and Rf ¹⁰³ include groups in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms is 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. Among them, Rf ¹⁰² and Rf ¹⁰³ are preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, and are preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group.

In the formula (f1-1), ¹ nf is an integer from 1 to 5, more preferably an integer of 1 to 3 is preferable, 1 or 2;

In the formula (f1-1), Rf ¹⁰¹ is preferably an organic group containing fluorine atom, a hydrocarbon group containing a fluorine atom.

The hydrocarbon group containing a fluorine atom may be any of linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, more preferably 1 to 10 carbon atoms. Particularly preferred.

The hydrocarbon group containing a fluorine atom preferably has at least 25% of the hydrogen atoms in the hydrocarbon group fluorinated, more preferably at least 50% fluorinated, and more preferably at least 60% The hydrophobicity of the resist film at the time of exposure becomes high.

Among them, a fluorinated hydrocarbon group having 1 to 5 carbon atoms is particularly preferable as Rf ¹⁰¹ , and a trifluoromethyl group, -CH ₂ -CF ₃ , -CH ₂ -CF ₂ -CF ₃ , -CH (CF ₃ ) ₂ , - CH ₂ -CH ₂ -CF ₃ , -CH ₂ -CH ₂ -CF ₂ -CF ₂ -CF ₂ -CF ₃ is most preferred.

The mass average molecular weight (Mw) (based on polystyrene conversion by gel permeation chromatography) of the component (F) is preferably from 1,000 to 50,000, more preferably from 5,000 to 40,000, and most preferably from 10,000 to 30,000. When the upper limit of the above range is not exceeded, the solubility in a resist solvent is sufficient for use as a resist. If the lower limit of the above range is exceeded, the dry etching resistance and the cross-sectional shape of the resist pattern are favorable.

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.

The component (F) may be used singly or in combination of two or more.

Is preferably used in a proportion of 0.5 to 10 parts by mass based on 100 parts by mass of the component (F) and the component (A).

The resist composition of the present invention may further contain miscible additives such as an additional resin for improving the performance of the resist film, a dissolution inhibitor, a plasticizer, a stabilizer, a colorant, a halation inhibitor, Can be added and contained.

[Component (S)] [

The resist composition of this embodiment can be prepared by dissolving the resist material in an organic solvent (hereinafter sometimes referred to as "(S) component").

The component (S) may be any one capable of dissolving each component to be used and forming a homogeneous solution. Conventionally, any one or two or more kinds of solvents known as solvents for chemically amplified resists Can be used.

Examples of the solvent include lactones such as? -Butyrolactone; ketones such as acetone, methyl ethyl ketone (MEK), cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, Polyhydric alcohols such as diethylene glycol, propylene glycol and dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate or dipropylene glycol monoacetate; Or derivatives of polyhydric alcohols such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, monobutyl ether and monophenyl ether compounds having an ether bond, among the above-mentioned compounds having an ester bond , Propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) Preferred examples thereof include cyclic ethers such as dioxane, esters such as methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate and ethyl ethoxypropionate An anisole, an ethylbenzyl ether, a cresyl methyl ether, a diphenyl ether, a dibenzyl ether, a phenetole, a butyl phenyl ether, an ethylbenzene, a diethylbenzene, a pentylbenzene, an isopropylbenzene, a toluene, a xylene, Aromatic organic solvents such as tylene, dimethylsulfoxide (DMSO), and the like.

These organic solvents may be used alone or in combination of two or more.

Among them, PGMEA, PGME,? -Butyrolactone, EL, and cyclohexanone are preferable.

A mixed solvent in which PGMEA and a polar solvent are mixed is also preferable. The compounding ratio (mass ratio) may be suitably determined in consideration of the compatibility of the PGMEA and the polar solvent, but is preferably within the range of 1: 9 to 9: 1, more preferably 2: 8 to 8: 2 desirable.

More specifically, when EL or cyclohexanone is blended 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. When PGME is blended as a polar solvent, the mass ratio of PGMEA: PGME is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, still more preferably 3: 7: 3. Mixed solvents of PGMEA, PGME and cyclohexanone are also preferable.

Further, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and? -Butyrolactone is also preferable. In this case, as the mixing ratio, the mass ratio of the former to the latter is preferably 70:30 to 95: 5.

The amount of the component (S) to be used is not particularly limited and is appropriately set in accordance with the thickness of the coating film at a concentration applicable to a substrate or the like. In general, the solid content concentration of the resist composition is in the range of 1 to 20% by mass, preferably 2 to 15% by mass.

According to the resist composition of the present invention, a resist pattern with reduced roughness can be formed.

The resist composition of the present invention contains a polymer (A1) having a structural unit (a0) containing a lactone-containing cyclic group having an electron-withdrawing substituent (X). By using the component (A1), deterioration of the sensitivity is suppressed when the resist pattern is formed, and good sensitivity is maintained. In addition, by having the constituent unit (a0), the solubility of the component (A1) in an organic solvent becomes high and can be stably dissolved in a resist solvent.

The resist composition of the present invention contains an acid generator (B1) comprising a compound having a specific anion moiety. Since the acid generated by the exposure of the component (B1) is short-diffused, the roughness of the resist pattern side wall and the like can be reduced. In addition, by using the component (B1), the acid dissociable group can be easily dissociated from the base resin. In addition, in the alkali developing process, the alkali dissolution is hardly caused by inhibition of dissolution.

In the resist composition of the present invention, the combination of the component (A1) having the constituent unit (a0) and the component (B1) having the specific anion moiety has a remarkable effect of reducing the roughness Loses.

In addition, according to the resist composition of the present invention, it is possible to form a resist pattern with reduced roughness while maintaining better sensitivity. Further, in the resist pattern formation using the resist composition of the present invention, the exposure margin (EL margin), which is an index of the amount of change in the pattern size accompanying the fluctuation of the exposure amount, is difficult to be compatible with the roughness reduction.

≪ Method of forming resist pattern &

The resist pattern forming method of the second aspect of the present invention comprises the steps of forming a resist film on a support using the resist composition of the first aspect of the present invention, exposing the resist film, and developing the exposed resist film And forming a resist pattern.

The resist pattern forming method of the present embodiment can be carried out, for example, as follows.

First, a resist composition according to the first embodiment is coated on a support with a spinner or the like and baked (post-application baked (PAB)) treatment is performed for 40 to 120 seconds at a temperature of, for example, Preferably 60 to 90 seconds, to form a resist film.

Next, using the exposure apparatus such as an ArF exposure apparatus, an electron beam lithography apparatus, and an EUV exposure apparatus, an exposure or mask pattern interposed between a mask (mask pattern) having a predetermined pattern formed thereon is interposed (Post exposure bake (PEB)) treatment is performed at a temperature of, for example, 80 to 150 ° C for 40 to 120 seconds, preferably 60 to 120 seconds, after performing selective exposure by drawing by direct irradiation of an electron beam, 90 seconds.

Next, the resist film is developed. The developing treatment is carried out using a developing solution (organic developing solution) containing an alkaline developing solution in the case of the alkali developing process and an organic solvent in the case of the solvent developing process.

After the developing treatment, rinsing treatment is preferably carried out. In the case of the alkaline development process, rinsing is preferably performed using purified water, and in the case of the solvent development process, a rinsing solution containing an organic solvent is preferably used.

In the case of the solvent developing process, a treatment for removing the developing solution or the rinsing liquid adhering to the pattern by the supercritical fluid may be performed after the developing treatment or the rinsing treatment.

After the development treatment or the rinsing treatment, drying is performed. In some cases, a baking process (post-baking) may be performed after the above developing process. In this manner, 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 having a predetermined wiring pattern formed thereon. More specifically, a metal substrate such as a silicon wafer, copper, chromium, iron or aluminum, or a glass substrate can be given. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold and the like can be used.

As the support, an inorganic and / or organic film may be formed on the above-described substrate. As the inorganic film, an inorganic anti-reflection film (inorganic BARC) can be mentioned. Examples of the organic film include an organic antireflection film (organic BARC) and an organic film such as a lower organic film in the multilayer resist method.

Here, the multilayer resist method is a method in which at least one organic film (lower organic film) and at least one resist film (upper resist film) are formed on a substrate, and a resist pattern formed on the upper resist film is used as a mask And patterning of the underlying organic film is performed, and it is considered that a pattern of the Gauss spectrum ratio can be formed. That is, according to the multilayer resist method, since a required thickness can be ensured by the lower organic film, the resist film can be made thinner, and a fine pattern of a high aspect ratio can be formed.

In the multilayer resist method, basically, a method of forming a two-layer structure of an upper resist film and a lower layer organic film (two-layer resist method), and a method of forming an intermediate layer (metal thin film or the like) And a method of forming a multilayer structure of three or more layers (a three-layer resist method).

The wavelength used for exposure is not particularly limited and may be selected from the group consisting of ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet) Ray or the like. The resist composition has high usability for KrF excimer laser, ArF excimer laser, EB or EUV, and is particularly useful for ArF excimer laser, EB or EUV.

The exposure method of the resist film may be a conventional exposure (dry exposure) or an immersion exposure (liquid immersion lithography) in an inert gas such as air or nitrogen.

The immersion exposure is an exposure method in which a space between a resist film and a lens in the lowermost position of the exposure apparatus is filled with a solvent (immersion medium) having a refractive index larger than that of air and exposure (immersion exposure) is performed in this state.

As the immersion medium, a solvent which is larger than the refractive index of air and has a refractive index smaller than the refractive index of the exposed resist film is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.

Examples of the solvent that is larger than the refractive index of air and has a refractive index smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicone solvent, and a hydrocarbon solvent.

Specific examples of the fluorine-based inert liquid include liquids containing 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 , C ₅ H ₃ F ₇ , And preferably has a boiling point of 70 to 180 ° C, more preferably 80 to 160 ° C. If the fluorine-based inert liquid has a boiling point in the above-mentioned range, it is preferable that the medium used for liquid immersion can be removed by a simple method after the end of exposure.

As the fluorine-based inert liquid, a perfluoroalkyl compound in which the hydrogen atoms of the alkyl group are all substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.

Specific examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point: 102 ° C), and perfluoroalkylamine compounds include perfluoro (Boiling point 174 占 폚).

As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility and the like.

Examples of the alkali developing solution used in the developing treatment in the alkali development process include an aqueous solution of 0.1 to 10 mass% tetramethylammonium hydroxide (TMAH).

The organic solvent contained in the organic developing solution used in the developing treatment in the solvent developing process may be any solvent that can dissolve the component (A) (component (A) before exposure) and may be appropriately selected from known organic solvents. Specific examples thereof include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents and ether solvents, hydrocarbon solvents and the like.

The ketone-based solvent is an organic solvent containing C-C (= O) -C in the structure. The ester solvent is an organic solvent containing C-C (= O) -O-C in the structure. The alcoholic solvent is an organic solvent containing an alcoholic hydroxyl group in its structure, and the " alcoholic hydroxyl group " means a hydroxyl group bonded to the carbon atom of the aliphatic hydrocarbon group. The nitrile-based solvent is an organic solvent containing a nitrile group in its structure. The amide-based solvent is an organic solvent containing an amide group in its structure. The ether solvent is an organic solvent containing C-O-C in the structure.

In the organic solvent, an organic solvent containing a plurality of functional groups characterizing each of the solvents is also present in the structure. In this case, it is assumed that any solvent type including the functional group of the organic solvent is included. For example, diethylene glycol monomethyl ether corresponds to any of alcohol-based solvents and ether-based solvents in the above-mentioned classification.

The hydrocarbon-based solvent is a hydrocarbon solvent which is made of a hydrocarbon which may be halogenated and has no substituent other than 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 preferable.

As the organic solvent contained in the organic developing solution, a polar solvent is preferable among them, and a ketone solvent, an ester solvent, a nitrile solvent and the like are preferable.

Specific examples of the solvent include ketone-based solvents such as 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1- -Acetone acetone, acetone acetone, ionone, diacetyl alcohol, acetyl carbinol, acetone, acetone, acetone, acetone, Phenol, methylnaphthyl ketone, isophorone, propylene carbonate,? -Butyrolactone, and methyl amyl ketone (2-heptanone).

Methylamyl ketone (2-heptanone) is preferred as the ketone-based solvent.

Examples of the ester-based solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl lactate, methoxyacetate, ethoxyacetate, propylene glycol monomethyl ether acetate, ethylene glycol Monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, Diethylene glycol monomethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, - Methode Propyleneglycol monomethyl ether acetate, propyleneglycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, propyleneglycol monomethylether acetate, propyleneglycol monomethylether acetate, Propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, Propyleneglycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, , Propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, , Ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, Methoxypropionate, propyl-3-methoxypropionate, and the like.

As the ester-based solvent, butyl acetate is preferable.

The nitrile-based solvent includes, for example, acetonitrile, propionitrile, valeronitrile, butyronitrile, and the like.

If necessary, known additives may be added to the organic developer. Examples of the additive include a surfactant. The surfactant is not particularly limited and, for example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used. As the surfactant, a nonionic surfactant is preferable, and a fluorinated surfactant or a silicon surfactant is more preferable.

When a surfactant is blended, the blending amount thereof is usually 0.001 to 5 mass%, preferably 0.005 to 2 mass%, and more preferably 0.01 to 0.5 mass%, based on the total amount of the organic developer.

The developing treatment can be carried out by a known developing method. For example, a developing method (dip method) for immersing the support in a developing solution for a predetermined time, a method of mounting the developing solution on the surface of the support by surface tension, A method of spraying a developer to the surface of a support (spray method), a method of continuously extracting a developer while scanning a developing solution nozzle at a constant speed on a support rotating at a constant speed (dynamic administration method) And the like.

Examples of the organic solvent to be contained in the rinsing liquid used for the rinsing treatment after the developing treatment in the solvent developing process include those suitably selected from organic solvents exemplified as organic solvents for the organic developing solution, Can be used. Usually, at least one solvent selected from a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent and an ether solvent is used. Among them, at least one selected from a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent and an amide-based solvent is preferable and at least one selected from an alcoholic solvent and an ester- Alcohol-based solvents are particularly preferred.

The alcoholic solvent used in the rinsing liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be any of linear, branched and cyclic. Specific examples thereof include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, - octanol, benzyl alcohol, and the like. Among them, 1-hexanol, 2-heptanol and 2-hexanol are preferable, and 1-hexanol or 2-hexanol is more preferable.

These organic solvents may be used singly or in combination of two or more kinds. It may be mixed with an organic solvent or water other than the above. The amount of water in the rinsing liquid is preferably 30 mass% or less, more preferably 10 mass% or less, even more preferably 5 mass% or less, more preferably 3 mass% or less, Or less is particularly preferable.

A known additive may be added to the rinsing liquid if necessary. As the additive, for example, a surfactant can be mentioned. Examples of the surfactant include the same ones as described above. Nonionic surfactants are preferred, and fluorinated surfactants or silicone surfactants are more preferred.

When a surfactant is blended, the blending amount thereof is usually 0.001 to 5 mass%, preferably 0.005 to 2 mass%, and more preferably 0.01 to 0.5 mass%, based on the total amount of the rinse liquid.

The rinsing treatment (rinsing treatment) using the rinsing liquid can be carried out by a known rinsing method. Examples of the method include a method (rotation coating method) of continuously extracting the rinsing liquid on a support rotating at a constant speed, a method (dip method) of immersing the support in a rinsing liquid for a predetermined time (Spray method), and the like.

Example

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

In this embodiment, the compound represented by the formula (1) is referred to as "compound (1)" and the compound represented by the other formula is described in the same manner.

≪ Production Example of Polymer Compound &

The polymer compound used as the base component in this Example was obtained by using a compound represented by the following formula as a monomer in a predetermined molar ratio and copolymerizing by a known radical polymerization method.

(53)

(Polymer compound 1 to 6)

The monomer composition ratio (ratio of each constitutional unit in the structure (molar ratio)) of the polymer compound obtained by ¹³ C-NMR to the obtained polymer compound 1 to 6, mass average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement, And the molecular weight dispersion (Mw / Mn) are shown in Table 1.

≪ Preparation of resist composition >

(Examples 1 to 7 and Comparative Examples 1 to 4)

Each component shown in Table 2 was mixed and dissolved to prepare resist compositions for each example.

In Table 2, the respective abbreviations have the following meanings respectively. The values in [] are the compounding amount (parts by mass).

(A) -1 to (A) -6: said polymer compound 1 to 6;

(B1) -1 to (B1) -4: An acid generator comprising a compound represented by the following general formula (B1) -1 to (B1) -4.

(B2) -1: An acid generator comprising a compound represented by the following formula (B2) -1.

(B2) -2: Triphenylsulfonium nonafluoro-n-butanesulfonate.

(D) -1: A photodegradable base comprising a compound represented by the following formula (D) -1.

(F) -1: A fluorinated polymer compound represented by the following formula (F) -1. The mass average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement was 25000, and the molecular weight dispersion degree (Mw / Mn) was 2.0.

(S) -1: Mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether / cyclohexanone = 45/30/25 (mass ratio).

(54)

The obtained resist composition was used to form a resist pattern, and evaluation of sensitivity, line-through roughness (LWR), and exposure margin (EL margin) were carried out as follows.

≪ Formation of resist pattern &

ARC95 " (trade name, manufactured by Brewer Science) was applied on a 12-inch silicon wafer using a spinner and baked on a hot plate at 205 DEG C for 60 seconds and dried to obtain an organic An antireflection film was formed.

Subsequently, a resist composition of each example was coated on the organic antireflective film using a spinner, pre-baked (PAB) treatment was carried out on a hot plate at a temperature of 110 캜 for 60 seconds and dried to form a film having a thickness of 90 nm Of a resist film was formed.

Next, ArF exposure was performed on the resist film by a Arithmetic ArF exposure apparatus NSR-S609B (manufactured by Nikon Corporation; NA (numerical aperture) = 1.07, Dipole 0.97 / 0.78 with polano, immersion medium: water) Excimer laser (193 nm) was selectively irradiated.

Thereafter, post-exposure baking (PEB) treatment was performed at a temperature of 95 캜 for 60 seconds.

Subsequently, alkali development was performed for 10 seconds with a 2.38% by mass aqueous solution of TMAH (trade name: NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) at 23 占 폚 and then rinsed with pure water for 30 seconds, And was then shaken and dried.

As a result, a 1: 1 line-and-space (LS) pattern having a line width of 50 nm and a pitch of 100 nm was formed in each example.

In forming each example resist pattern, the optimum exposure amount (sensitivity) Eop (mJ / cm 2) at which the LS pattern was formed was obtained. The results are shown in Table 3.

[Evaluation of line-through roughness (LWR)]

The LS pattern formed by the above-mentioned < Formation of resist pattern > was subjected to measurement of the space width in the length direction of the space by SEM (scanning electron microscope, accelerating voltage 300 V, trade name: S-9380, Hitachi High Technologies) (3s) of the standard deviation (s) was obtained from the result, and a value (nm) averaged over 3s of 400 sites was calculated as a measure indicating the LWR. The results are shown in Table 3.

The smaller the value of 3s, the smaller the roughness of the line width and the more uniform LS pattern was obtained.

[Evaluation of exposure margin (EL margin)] [

The exposure amount when the line of the LS pattern was formed within the range of ± 5% (47.5 nm to 52.5 nm) of the target dimension (line width of 50 nm) was found by the above <formation of the resist pattern> Margin (unit:%) was obtained. The results are shown in Table 3.

EL margin (%) = (| E1 - E2 | / Eop) 100

E1: exposure dose (mJ / cm &lt; 2 &gt;) when an LS pattern with a line width of 47.5 nm was formed

E2: exposure dose (mJ / cm &lt; 2 &gt;) when an LS pattern having a line width of 52.5 nm was formed;

The larger the value of the EL margin, the smaller the amount of change in the pattern size accompanying the fluctuation of the exposure amount.

From the results shown in Table 3, it can be confirmed that the resist compositions of Examples 1 to 7 to which the present invention is applied can form a resist pattern with reduced roughness.

Claims (4)

1. A resist composition comprising a base component (A) whose solubility in a developer is changed by the action of an acid and an acid generator component (B) which generates an acid upon exposure,
(A) comprises the polymer (A1) having the structural unit (a0) represented by the following general formula (a0-1)
Wherein the acid generator component (B) comprises an acid generator (B1) comprising a compound represented by the following general formula (b1).
[Chemical Formula 1]

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ⁰ is a divalent hydrocarbon group which may have a substituent. n _a0 is an integer of 0 to 2; Ra ¹ and Ra ² are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group or an alkylthio group, or Ra ¹ and Ra ² are bonded to each other to form an oxygen atom (-O-) May be an alkylene group having 1 to 6 carbon atoms, an ether linkage, or a thioether linkage which may contain a linking group (-S-). Ra ^'01 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydroxyalkyl group having 1 to 6 carbon atoms which may have a hydroxy group protected by a protective group and may have a halogen atom, a carboxyl group , Or a substituted oxycarbonyl group. 'When ⁰¹ is present, a plurality of Ra' 2 or more Ra ⁰¹ is the same or different to each other. X is a substituent selected from the group consisting of a halogen atom, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group and a cyano group. When two or more X's are present, the plurality of X's may be the same or different from each other. p ₀ is an integer of 0 to 8; q ₀ is an integer from 1 to 9.]
(2)

Wherein R ¹⁰¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. q &quot; is an integer of 1 to 20; m is an integer of 1 or more, and M ^{m +} is an organic cation of m. The method according to claim 1,
(A1) in which the polymer compound (A1) has an acid-decomposable group whose polarity is increased by the action of an acid. 3. The method of claim 2,
Wherein the polymer compound (A1) comprises a structural unit (a2) (excluding the structural unit (a0)) comprising a lactone-containing cyclic group, -SO ₂ -containing cyclic group or a carbonate-containing cyclic group. A process for producing a resist pattern, comprising the steps of: forming a resist film on a support using the resist composition according to any one of claims 1 to 3; exposing the resist film; and developing the resist film to form a resist pattern Wherein the resist pattern forming step comprises the steps of: