KR20200059157A - Resist composition and method of forming resist pattern - Google Patents

Abstract

The present invention relates to a resist composition comprising: a substrate component (A) of which solubility with respect to a developing solution changes by the action of an acid; and a dissolution-preventing agent (Z) which suppresses the solubility with respect to the developing solution, wherein the dissolution-preventing agent (Z) has a mass average molecular weight of 3,000 or less and comprises a compound (Z1) having a phenolic hydroxyl group or a carboxylic group in molecule, and a compound (Z2) having a mass average molecular weight of 3,000 or less and represented by general formula (z2). (In the formulas: R_z^(20) is an acid-dissociable group; R_z^(30) is a hydrogen atom or an organic group; and n1 is an integer of 1-6 while n2 is an integer of 0-5, wherein n1 + n2 = 6).

Description

Resist composition and method of forming resist pattern {RESIST COMPOSITION AND METHOD OF FORMING RESIST PATTERN}

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

This application claims priority based on Japanese Patent Application No. 2018-217631 filed in Japan on November 20, 2018, and Japanese Patent Application No. 2019-188955 filed in Japan on October 15, 2019, The contents are used here.

In a lithography technique, a step of forming a resist pattern of a predetermined shape on the resist film, for example, by forming a resist film made of a resist material on a substrate, subjecting the resist film to selective exposure, and developing processing This is carried out. A resist material in which the exposed portion of the resist film changes to a property that is soluble in the developer solution is positive, and a resist material in which the exposed portion of the resist film is changed to a property that is not dissolved in the developer solution is called negative.

In recent years, in the manufacture of semiconductor devices and liquid crystal display devices, the refinement of patterns has been rapidly progressed due to advances in lithography technology. As a method of miniaturization, short wavelength (high energy) of the exposure light source is generally performed. Specifically, conventionally, ultraviolet rays represented by g-line and i-line have been used. Currently, mass production of semiconductor devices using KrF excimer laser light or ArF excimer laser light has been carried out. In addition, studies have been conducted on EUV (extreme ultraviolet rays), EB (electron beam), X-rays, etc. of shorter wavelengths (higher energy) than these excimer ray beams.

The resist material is required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing fine-dimensional patterns.

As a resist material satisfying such a demand, conventionally, a chemically amplified resist composition containing a base component whose solubility in a developer is changed by the action of an acid and an acid generator component generating an acid by exposure is used. have.

For example, when the developer is an alkali developer (alkali developing process), as a positive chemically amplified resist composition, a resin component (base resin) and an acid generator that increase solubility in an alkali developer by the action of an acid Ingredients containing those are generally used. When a resist film formed using such a resist composition is selectively exposed at the time of forming the resist pattern, acid is generated from the acid generator component in the exposed portion, and the polarity of the base resin increases due to the action of the acid. The exposed portion of the resist film is soluble in the alkali developer. Therefore, a positive pattern in which the unexposed portion of the resist film remains as a pattern is formed by alkali development.

On the other hand, when such a chemically amplified resist composition is applied to a solvent developing process using a developer (organic developer) containing an organic solvent, as the polarity of the base resin increases, solubility in the organic developer relatively decreases. The unexposed portion of the resist film is dissolved and removed with an organic developer, thereby forming a negative resist pattern in which the exposed portion of the resist film remains as a pattern. In this way, the solvent developing process for forming the negative resist pattern is sometimes referred to as a negative developing process.

In the above-mentioned chemically amplified resist composition, in order to suppress the film reduction of the resist film at the time of formation of the resist pattern, and to improve the difference in solubility (dissolution contrast) of the exposed portion and the unexposed portion of the resist film, the solubility in the developer is suppressed. It is known to mix | dissolve the dissolution preventing agent mentioned above (for example, refer patent documents 1-3).

In recent years, photofabrication has become the mainstream of precision micromachining technology. With photofabrication, the chemically amplified resist composition is applied to the surface of a workpiece to form a resist film, and a resist pattern having a predetermined shape is formed on the resist film, and chemical etching, electrolytic etching, or electroplating is used as a mask. Refers to a processing technology that manufactures various precision parts by performing electroforming and the like as main components.

Japanese Patent Application Publication No. 2006-328241 Japanese Patent Application Publication No. 2007-206425 Japanese Patent Application Publication No. 2008-122932

In such photofabrication, a thick film resist film having a film thickness of, for example, a micron order may be formed on the surface of a workpiece, depending on the application, etc., and a resist pattern may be formed to perform etching or the like. For example, in the development of a three-dimensional structure device (three-dimensional NAND), a memory fabricated using a thick-film resist pattern is stacked in dozens of layers in the longitudinal direction to increase the capacity of the memory.

As a result of examination by the present inventors, when a thick-film resist film of a micron order was formed by using a chemically amplified resist composition containing a conventional dissolution preventing agent, and etching was performed by forming a resist pattern, etching resistance was sometimes insufficient. On the other hand, when a thick film resist film is formed by using a chemically amplified resist composition containing no dissolution preventing agent, and when a resist pattern is formed, a film reduction of the resist film occurs during formation of the resist pattern, thereby forming a pattern having a desired shape. There were cases where it was not possible.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist composition capable of forming a pattern having good etching resistance and a good shape, and a method of forming a resist pattern using the resist composition.

In order to solve the said subject, this invention employs the following structures.

That is, the first aspect of the present invention is a resist composition in which acid is generated by exposure and the solubility in a developer is changed by the action of an acid, and the base component whose solubility in a developer is changed by the action of an acid A compound containing (A) and a solubilizing agent (Z) that suppresses solubility in a developing solution, wherein the solubilizing agent (Z) has a mass average molecular weight of 3000 or less, and has a phenolic hydroxyl group or a carboxyl group in the molecule ( It is a resist composition containing Z1) and a compound (Z2) having a mass average molecular weight of 3000 or less and represented by the following general formula (z2).

[Formula 1]

[Wherein, R _z ²⁰ is an acid dissociative group. R _z ³⁰ is a hydrogen atom or an organic group. n1 is an integer of 1-6, n2 is an integer of 0-5. However, n1 + n2 = 6.]

In a second aspect of the present invention, a step of forming a resist film using the resist composition on the support (i), a step of exposing the resist film (ii), and developing the resist film after the exposure to form a resist pattern It is the method of forming a resist pattern which has a process (iii).

ADVANTAGE OF THE INVENTION According to this invention, the resist composition which has good etching resistance and can form a pattern of a favorable shape, and the resist pattern formation method using the resist composition can be provided.

In this specification and the claims of this patent, "aliphatic" is defined as a concept relative to aromatics and means a group, a compound, or the like that does not have aromaticity.

The "alkyl group" is intended to contain a monovalent saturated hydrocarbon group of a straight chain, branched chain, and cyclic form, unless otherwise specified. The alkyl group in the alkoxy group is also the same.

The "alkylene group" is intended to contain a divalent saturated hydrocarbon group of a straight chain, branched chain, and cyclic type, unless otherwise specified.

The "halogenated alkyl group" is a group in which part or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

The "fluorinated alkyl group" or "fluorinated alkylene group" refers to a group in which part or all of the hydrogen atoms of the alkyl group or alkylene group are substituted with fluorine atoms.

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

When describing "may have a substituent" or "may have a substituent", a hydrogen atom (-H) is substituted with a monovalent group, and a methylene group (-CH _2- ) is substituted with a divalent group. Includes both.

"Exposure" is a concept including the overall irradiation of radiation.

"Structural unit derived from acrylic acid ester" means a structural unit formed by cleavage of an ethylenic double bond of an acrylic acid ester.

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

In the acrylic acid ester, a hydrogen atom bonded to a carbon atom at the α position may be substituted with a substituent. The substituent (R ^α0 ) for substituting a hydrogen atom bonded to the carbon atom at the α position is an atom or group other than a hydrogen atom, and examples thereof include an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, and the like. have. In addition, it also includes an itaconic acid diester in which the substituent (R ^α0 ) is substituted with a substituent containing an ester bond, or α hydroxyacrylic ester in which the substituent (R ^α0 ) is substituted with a hydroxyalkyl group or a group modified with the hydroxyl group thereof. do. Further, the carbon atom at the α position of the acrylic acid ester is a carbon atom to which the carbonyl group of acrylic acid is bonded unless otherwise specified.

Hereinafter, the acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α position is substituted with a substituent may be referred to as an α-substituted acrylic acid ester. Moreover, an acrylic acid ester and an alpha substituted acrylic acid ester are collectively called "(alpha substituted) acrylic acid ester."

The "constituent unit derived from acrylamide" means a structural unit that is formed by cleaving the ethylenic double bond of acrylamide.

In acrylamide, the hydrogen atom bonded to the carbon atom at the α position may be substituted with a substituent, or one or both hydrogen atoms of the amino group of acrylamide may be substituted with a substituent. Further, the carbon atom at the α position of acrylamide is a carbon atom to which the carbonyl group of acrylamide is bonded unless otherwise specified.

As a substituent which substitutes the hydrogen atom couple | bonded with the carbon atom of the α-position of acrylamide, the thing similar to what was mentioned as the substituent of the α-position (substituent (R ^α0 )) in the said α-substituted acrylic acid ester.

The "constituent unit derived from hydroxystyrene" means a structural unit formed by cleavage of the ethylenic double bond of hydroxystyrene. The "constituent unit derived from a hydroxystyrene derivative" means a structural unit formed by cleavage of an ethylenic double bond of a hydroxystyrene derivative.

The term "hydroxystyrene derivative" refers to a concept in which the hydrogen atom at the α position of hydroxystyrene is substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As their derivatives, the hydrogen atom in the hydroxyl group of the hydroxystyrene which may be substituted with a substituent at the hydrogen atom in the α position is substituted with an organic group; The thing which the substituent other than the hydroxyl group couple | bonded with the benzene ring of the hydroxystyrene which the hydrogen atom of the alpha position may be substituted with the substituent is mentioned. Note that the α position (the carbon atom at the α position) refers to a carbon atom to which the benzene ring is attached, unless otherwise specified.

As a substituent which substitutes the hydrogen atom of the alpha position of hydroxystyrene, the thing similar to what was mentioned as the substituent of the alpha position in the said alpha substituted acrylic acid ester is mentioned.

"Constituent unit derived from vinylbenzoic acid or vinylbenzoic acid derivative" means a structural unit formed by cleavage of an ethylenic double bond of vinylbenzoic acid or vinylbenzoic acid derivative.

The "vinyl benzoic acid derivative" is a concept including a hydrogen atom at the α position of vinylbenzoic acid substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. As their derivatives, the hydrogen atom at the carboxyl group of vinylbenzoic acid in which the hydrogen atom at the α position may be substituted with a substituent is substituted with an organic group; The thing which the substituent other than a hydroxyl group and a carboxy group couple | bonded with the benzene ring of the vinylbenzoic acid in which the hydrogen atom of the alpha position may be substituted with the substituent is mentioned. Note that the α position (the carbon atom at the α position) refers to a carbon atom to which the benzene ring is attached, unless otherwise specified.

The "styrene derivative" is a concept including a hydrogen atom at the styrene α position substituted with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. Examples of the derivatives include those in which the hydrogen atom at the α position is substituted with a substituent on a benzene ring of hydroxystyrene, which may be substituted with a substituent. Note that the α position (the carbon atom at the α position) refers to a carbon atom to which the benzene ring is attached, unless otherwise specified.

"Structural units derived from styrene" and "structural units derived from styrene derivatives" refer to structural units formed by cleavage of ethylenic double bonds of styrene or styrene derivatives.

The alkyl group as the substituent at the α position is preferably a linear or branched chain alkyl group, specifically, an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, iso Butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.

Moreover, the halogenated alkyl group as a substituent of the α position specifically, a group in which a part or all of the hydrogen atoms of the “alkyl group as a substituent of the α position” 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.

 Moreover, the hydroxyalkyl group as a substituent of the alpha position specifically, group which substituted some or all of the hydrogen atom of the said "alkyl group as a substituent of the alpha position" with a hydroxyl group is mentioned. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and 1 is most preferred.

In the present specification and claims, depending on the structure represented by the formula, there may be a sub-carbon, and an enantiomer or a diastereomer may exist. In that case, it is represented by isomers in one chemical formula. These isomers may be used alone or as a mixture.

(Resist composition)

The resist composition according to the first aspect of the present invention is a resist composition that generates an acid by exposure and the solubility in a developer is changed by the action of the acid.

As an embodiment of such a resist composition, the base component (A) (hereinafter also referred to as "(A) component") whose solubility in a developer is changed by the action of an acid, and a solubilizing agent that suppresses solubility in a developer ( And a resist composition containing Z) (hereinafter also referred to as "(Z) component") and organic solvent component (S) (hereinafter also referred to as "(S) component").

The resist composition of the present embodiment is suitable for forming a resist pattern that performs exposure using an exposure light source such as ultraviolet rays such as g-rays or i-rays or KrF excimer laser.

Moreover, the resist composition of this embodiment is suitable for forming a resist film of, for example, 1 to 10 µm on a support, and is particularly preferable for forming a resist pattern formed by forming a thick film resist film. The thick film referred to herein refers to a film having a thickness of 3 µm or more. The resist composition of the present embodiment is preferably suitable for forming a resist film having a thickness of 3 µm or more, and a thickness of 3.5 µm or more, and more preferably 4 µm or more, among these ranges.

When a resist film is formed using such a resist composition, and selective exposure is performed on the resist film, acid is generated in the exposed portion of the resist film, and the action of the acid changes the solubility of the component (A) into the developer. On the other hand, since the solubility of component (A) in the unexposed portion of the resist film does not change, the difference in solubility in the developer occurs between the exposed portion and the unexposed portion. Therefore, when the resist film is developed, when the resist composition is positive, the resist film exposed portion is dissolved and removed to form a positive resist pattern, and when the resist composition is negative, the resist film unexposed portion is dissolved and removed to be negative. A resist pattern of the mold is formed.

In the present specification, a resist composition in which the exposed portion of the resist film is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition in which the unexposed portion of the resist film is dissolved and removed to form a negative resist pattern is a negative resist. It is called a composition.

The resist composition of this aspect may be a positive resist composition or a negative resist composition.

Further, the resist composition of the present embodiment may be for an alkali developing process using an alkali developer for developing treatment at the time of forming a resist pattern, or for a solvent developing process using a developing solution (organic developer) containing an organic solvent for the developing treatment. May be

The resist composition of this aspect has an acid generating ability to generate an acid by exposure, and the component (A) may generate an acid by exposure, and the additive component blended separately from the component (A) by exposure Acid may be generated.

Specifically, the resist composition of this aspect may contain (1) an acid generator component (B) (hereinafter referred to as "(B) component") that generates an acid by exposure, and (2) ( A) The component may be a component that generates an acid by exposure, or (3) the component (A) is a component that generates acid by exposure, and may further contain a component (B).

That is, in the case of the above (2) and (3), the component (A) becomes "a base component that generates an acid by exposure, and the solubility in a developing solution changes by the action of the acid". (A) When a component is a base component which generates an acid by exposure and the solubility in a developer solution changes by the action of an acid, the component (A1) described later generates an acid by exposure, and further, It is preferable that it is a high molecular compound whose solubility in a developer is changed by the action of an acid. As such a polymer compound, a resin having a structural unit that generates an acid by exposure can be used. A well-known thing can be used as a structural unit which produces an acid by exposure.

Among these, the above-mentioned resist composition is particularly preferable in the case of the above (1), that is, the component (A) and the component (Z), and further the component (B).

<Component (A)>

In the resist composition of the present embodiment, the component (A) is a base component whose solubility in a developer is changed by the action of an acid.

In the present invention, the "base component" is an organic compound having a film-forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film forming ability is improved, and it is easy to form a nano-level resist pattern.

Organic compounds used as the base component are roughly classified into non-polymers and polymers.

As the non-polymer, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, in the case of "low molecular compound", a non-polymer having a molecular weight of 500 or more and less than 4000 is shown.

As the polymer, one having a molecular weight of 1000 or more is usually used. Hereinafter, in the case of "resin", "polymer compound" or "polymer", a polymer having a molecular weight of 1000 or more is represented.

As the molecular weight of the polymer, it is assumed that 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 an alkali developing process" that forms a negative resist pattern in an alkali developing process, or a "solvent developing" that forms a positive resist pattern in a solvent developing process. In the case of "a positive resist composition for a process", as the component (A), preferably, a base component (A-2) soluble in an alkali developer (hereinafter referred to as the "(A-2) component") is used, and added Furnace, a crosslinking agent component is blended. In such a resist composition, for example, when acid is generated from the component (B) by exposure, the acid acts and crosslinking occurs between the component (A-2) and the crosslinking agent component, and as a result, the solubility in the alkali developer. Decreases (solubility in organic developer increases). Therefore, in forming a resist pattern, when the resist film obtained by applying the resist composition on a support is selectively exposed, the resist film exposed portion becomes poorly soluble in an alkali developer (soluble in an organic developer), while the resist Since the film unexposed portion does not change while being soluble in an alkali developer (insoluble in organic developer), a negative resist pattern is formed by developing with an alkali developer. Further, at this time, by developing with an organic developer, a positive resist pattern is formed.

As the preferable 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 alkyl ester of α- (hydroxyalkyl) acrylic acid or α- (hydroxyalkyl) acrylic acid disclosed in JP 2000-206694 A (preferably 1 to 1 carbon atoms) Resin having a structural unit derived from at least one selected from alkyl esters of 5); An acrylic resin or polycycloolefin resin which may be substituted with a substituent by a hydrogen atom bonded to a carbon atom at the α position having a sulfonamide group, as disclosed in U.S. Patent 6949325; Acrylic resin which may contain a fluorinated alcohol and hydrogen atom bonded to a carbon atom at the α position may be substituted with a substituent, disclosed in U.S. Patent No. 6949325, JP 2005-336452, and JP 2006-317803 A. ; The polycycloolefin resin having fluorinated alcohol, etc. disclosed in Japanese Patent Application Laid-Open No. 2006-259582 is preferable because it can form a good resist pattern with little swelling.

In addition, the α- (hydroxyalkyl) acrylic acid is an acrylic acid in which a hydrogen atom is bonded to a carbon atom at an α position to which a carboxy group is bonded, among acrylic acids in which a hydrogen atom bonded to a carbon atom at the α position may be substituted with a substituent. It represents one or both of α-hydroxyalkylacrylic acid in which a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) is bonded to a carbon atom at the α position.

As a crosslinking agent component, it is preferable to use an amino type crosslinking agent, such as glycoluril which has a methylol group or an alkoxymethyl group, or a melamine type crosslinking agent, for example, from the viewpoint of easy formation of a good resist pattern with little swelling. It is preferable that the compounding quantity of a crosslinking agent component is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

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

When the alkali developing process is applied, the component (A-1) is poorly soluble in the alkali developer before exposure. For example, when acid is generated from the component (B) by exposure, polarity is caused by the action of the acid. This increases, solubility in an alkali developer increases. Therefore, in forming a resist pattern, if the resist composition is selectively exposed to a resist film obtained by applying it on a support, the resist film exposed portion changes from poorly soluble to soluble in an alkali developer, while the resist film is minus Since the light portion is hardly soluble in alkali and does not change, a positive resist pattern is formed by alkali development.

On the other hand, when the solvent developing process is applied, the component (A-1) has high solubility in the organic developer before exposure, and when acid is generated from the component (B) by exposure, the polarity is increased by the action of the acid. , Solubility in organic developer decreases. Therefore, in forming a resist pattern, when the resist composition obtained by coating the resist composition on a support is selectively exposed, the resist film exposed portion changes from soluble to poorly soluble in an organic developer, while the resist film is minus Since the light portion does not change while being soluble, it is possible to form contrast between the exposed portion and the unexposed portion by developing with an organic developer, thereby forming a negative resist pattern.

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

In the resist composition of this embodiment, it is preferable that (A) component is the said (A-1) component. That is, the resist composition of the present embodiment is a "positive resist composition for an alkali developing process" that forms a positive resist pattern in an alkali developing process, or a "solvent developing" that forms a negative resist pattern in a solvent developing process. Negative resist composition for process ". As the component (A), at least one of a high molecular compound and a low molecular compound can be used.

When the component (A) is the component (A-1), it is preferable to include the resin component (A1) (hereinafter also referred to as “(A1) component”) as the component (A-1).

・ About (A1) ingredient

(A1) A component is a resin component, It is preferable to contain the high molecular compound which has the structural unit (a1) containing the acid-decomposable group whose polarity increases by the action of an acid.

As (A1) component, it is preferable to have a structural unit (a10) containing a hydroxystyrene skeleton in addition to the structural unit (a1).

Moreover, it is also preferable to have a structural unit (st) derived from styrene or its derivative further in addition to a structural unit (a1) as (A1) component.

Moreover, (A1) component may have structural units other than a structural unit (a1), a structural unit (a10), and a structural unit (st).

≪Composition unit (a1) ≫

The structural unit (a1) is a structural unit containing an acid-decomposable group whose polarity increases by the action of an acid.

The "acid-decomposable group" is a group having an acid-decomposable property capable of cleaving at least a part of the structure of the acid-decomposable group under the action of an acid.

Examples of the acid-decomposable group in which the polarity increases by the action of an acid include groups that decompose under the action of an acid to generate a polar group.

As a polar group, a carboxy group, a hydroxyl group, an amino group, a sulfo group (-SO ₃ H) etc. are mentioned, for example. Among these, a polar group containing -OH in the structure (hereinafter sometimes referred to as "OH-containing polar group") is preferable, a carboxy group or a hydroxyl group is more preferable, and a carboxy group is particularly preferable.

More specifically, an acid-decomposable group includes a group in which the polar group is protected by an acid-dissociable group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid-dissociable group).

Here, the term "acid dissociable group" means (i) a group having acid dissociation property that can cause cleavage of a bond between the acid dissociable group and atoms adjacent to the acid dissociable group by the action of an acid, or (ii) It refers to both of groups in which the bond between the acid-dissociable group and atoms adjacent to the acid-dissociable group can be cleaved by a decarbonation reaction occurring after some of the bonds are cleaved by the action of the acid.

The acid-dissociable group constituting the acid-decomposable group needs to be a group having a lower polarity than the polar group produced by the dissociation of the acid-dissociable group, whereby when the acid-dissociable group dissociates by the action of an acid, the acid-dissociable group A polar group with a higher polarity is formed and the polarity is increased. As a result, the polarity of the entire component (A1) increases. As the polarity increases, solubility in the developer is relatively changed, solubility increases when the developer is an alkali developer, and solubility decreases when the developer is an organic developer.

As an acid dissociable group, what has hitherto been proposed as an acid dissociable group of a base resin for a chemically amplified resist composition is mentioned.

As an acid dissociable group of a base resin for a chemically amplified resist composition, specifically, "acetal type acid dissociable group", "tertiary alkyl ester type acid dissociable group" described below, "class 3" And an alkyloxycarbonyl acid dissociative group.

Acetal acid dissociation period:

As the acid dissociable group protecting the carboxyl group or hydroxyl group among the polar groups, for example, an acid dissociable group represented by the following general formula (a1-r-1) (hereinafter sometimes referred to as an "acetal type acid dissociable group"). Can be mentioned.

[Formula 2]

[In the formula, Ra ' ¹ and Ra' ² are hydrogen atoms or alkyl groups. Ra ' ³ is a hydrocarbon group, and Ra' ³ may combine with 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 are hydrogen atoms.

When Ra ' ¹ or Ra' ² is an alkyl group, in the description of the α-substituted acrylic acid ester, examples of the alkyl group include the same alkyl groups as the substituents which may be bonded to the carbon atom at the α position, and have 1 to 1 carbon atoms. The alkyl group of 5 is preferable. Specifically, a linear or branched chain alkyl group is preferably mentioned. More specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, etc. may be mentioned, and methyl group or ethyl group It is more preferable, and 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 chain alkyl group or 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. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, methyl group, ethyl group or n-butyl group is preferable, and methyl group or ethyl group is more preferable.

The branched chain alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned, and it is an isopropyl group It is preferred.

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

As a monocyclic aliphatic hydrocarbon group, a group in which one hydrogen atom is removed from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane.

As the aliphatic hydrocarbon group having a polycyclic group, a group in which one hydrogen atom is removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, and iso And bornan, tricyclodecane, and tetracyclododecane.

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

The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4 n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms.

Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; And aromatic hetero rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. A pyridine ring, a thiophene ring, etc. are mentioned specifically, as an aromatic heterocycle.

Specifically as the aromatic hydrocarbon group for Ra ' ³ , a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); A group in which one hydrogen atom is removed from an aromatic compound (eg, biphenyl, fluorene, etc.) containing two or more aromatic rings; A group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2 -Aryl alkyl groups, such as a naphthyl ethyl group, etc.) etc. are mentioned. 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 carbon atoms, and particularly preferably 1 carbon atom.

The cyclic hydrocarbon group for Ra ' ³ may have a substituent. Examples of the substituent include -R ^P1 , -R ^P2 -OR ^P1 , -R ^P2 -CO-R ^P1 , -R ^P2 -CO-OR ^P1 , -R ^P2 -O-CO-R ^P1 ,- And R ^P2 -OH, -R ^P2 -CN, or -R ^P2 -COOH (hereinafter, these substituents are collectively referred to as "Ra ⁰⁵ ").

Here, R ^P1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. In addition, R ^P2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms. However, some or all of the hydrogen atoms of the chain saturated hydrocarbon group, the aliphatic cyclic saturated hydrocarbon group, and the aromatic hydrocarbon group of R ^P1 and R ^P2 may be substituted with a fluorine atom. The said aliphatic cyclic hydrocarbon group may have 1 or more of these substituents individually, and may have 1 or more of each of the above substituents.

Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl and decyl groups.

Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include, for example, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, and cyclododecyl group. Monocyclic aliphatic saturated hydrocarbon groups such as; Bicyclo [2.2.2] octanyl group, tricyclo [5.2.1.02,6] decanyl group, tricyclo [3.3.1.13,7] decanyl group, tetracyclo [6.2.1.13,6.02,7] dodecanyl group, ah And polycyclic aliphatic saturated hydrocarbon groups such as a damantyl group.

Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include a group in which one hydrogen atom is removed from aromatic hydrocarbon rings such as benzene, biphenyl, fluorene, naphthalene, anthracene and phenanthrene.

When Ra ' ³ combines with any one of Ra' ¹ and Ra ' ² to form a ring, a 4- to 7-membered ring is preferable as the cyclic group, and a 4- to 6-membered ring is more preferable. A tetrahydropyranyl group, a tetrahydrofuranyl group, etc. are mentioned as a specific example of this cyclic group.

Tertiary alkyl ester type acid dissociable group:

Among the polar groups, examples of the acid dissociable group protecting the carboxy group include an acid dissociable group represented by the following general formula (a1-r-2).

Moreover, among the acid dissociable groups represented by the following formula (a1-r-2), what is composed of an alkyl group is sometimes referred to as “tertiary alkyl ester type acid dissociable group” for convenience.

[Formula 3]

[In the formula, Ra ' ⁴ to Ra' ⁶ are each a hydrocarbon group, and Ra ' ⁵ and Ra' ⁶ may combine with each other to form a ring.]

Ra 'hydrocarbon group of ^4, there may be mentioned linear or branched alkyl group, or an alkenyl group of chain-cyclic, or a hydrocarbon cyclic.

The straight chain or branched chain alkyl group and the cyclic hydrocarbon group in Ra ' ⁴ (monocyclic group aliphatic hydrocarbon group, polycyclic group aliphatic hydrocarbon group, aromatic hydrocarbon group) are the same as those in the above Ra' ³ Can be.

The chain or cyclic alkenyl group in Ra ' ⁴ is preferably an alkenyl group having 2 to 10 carbon atoms.

Ra ^'5, Ra' hydrocarbon group of ^6, there may be mentioned the same ones as the Ra ^'3.

When Ra ' ⁵ and Ra' ⁶ combine with each other to form a ring, the group represented by the following general formula (a1-r2-1), the group represented by the following general formula (a1-r2-2), the following general formula (a1) The group represented by -r2-3) is preferably mentioned.

On the other hand, Ra ^'4 ~ Ra' ⁶ are not bonded to each other, there may be mentioned preferably a group represented by the following, when an independent hydrocarbon general formula (a1-r2-4).

[Formula 4]

[Wherein, Ra ^'10 of (a1-r2-1) is, represents a group represented by the group, or the following formula (a1-r2-r1) of 1 to 10 carbon atoms. Ra represents a group forming an aliphatic ring-shaped with a ^"11 is Ra, the carbon atom ¹⁰ is bonded. In formula (a1-r2-2), Ya is a carbon atom. Xa is a group forming a cyclic hydrocarbon group together with Ya. Some or all of the hydrogen atoms of the cyclic hydrocarbon group may be substituted. Ra ⁰¹ to Ra ⁰³ are each independently a hydrogen atom, a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all of the hydrogen atoms of the chain saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group may be substituted. Two or more of Ra ⁰¹ to Ra ⁰³ may be bonded to each other to form a cyclic structure. In formula (a1-r2-3), Yaa is a carbon atom. Xaa is a group forming an aliphatic cyclic group together with Yaa. Ra ⁰⁴ is an aromatic hydrocarbon group which may have a substituent. Equation (a1-r2-4) of, Ra is ^'12 and Ra' ^13, each independently, a monovalent chain-like saturated hydrocarbon group or a hydrogen atom of 1 to 10 carbon atoms. Some or all of the hydrogen atoms in the chain-saturated hydrocarbon group may be substituted. Ra ^'14 is a hydrocarbon group which may have a substituent. * Represents a bonding hand (hereinafter the same).]

[Formula 5]

[In the formula, Ya ⁰ is a quaternary carbon atom. Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ are each independently a hydrocarbon group which may have a substituent. However, at least one of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least one polar group.]

The formula (a1-r2-1) of, Ra 'group of ¹⁰ 1 to 10 carbon atoms in the formula (a1-r-1) Ra of the' group is either a linear or branched alkyl group of ³ desirable. Ra ^'10 is preferably an alkyl group having 1 to 5 carbon atoms.

In the formula (a1-r2-r1), Ya ⁰ is a quaternary carbon atom. That is, there are four neighboring carbon atoms that bind to Ya ⁰ (carbon atom).

In the formula (a1-r2-r1), Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ are each independently a hydrocarbon group which may have a substituent. The hydrocarbon groups for Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ are each independently a linear or branched chain alkyl group, a chain or cyclic alkenyl group, or a cyclic hydrocarbon group.

In Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , 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. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, methyl group, ethyl group or n-butyl group is preferable, and methyl group or ethyl group is more preferable.

In Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the branched chain alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned, and it is an isopropyl group It is preferred.

In Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the chain or cyclic alkenyl group is preferably an alkenyl group having 2 to 10 carbon atoms.

In Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the cyclic hydrocarbon group may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may also be polycyclic or monocyclic.

As a monocyclic aliphatic hydrocarbon group, a group in which one hydrogen atom is removed from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane.

As the aliphatic hydrocarbon group having a polycyclic group, a group in which one hydrogen atom is removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, and iso And bornan, tricyclodecane, and tetracyclododecane.

The aromatic hydrocarbon group for Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4 n + 2 π electrons, and may be monocyclic or polycyclic. It is preferable that carbon number of an aromatic ring is 5-30, 5-20 are more preferable, 6-15 are still more preferable, and 6-12 are especially preferable. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; And aromatic hetero rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. A pyridine ring, a thiophene ring, etc. are mentioned specifically, as an aromatic heterocycle. Specific examples of the aromatic hydrocarbon group include a group in which one hydrogen atom is removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); A group in which one hydrogen atom is removed from an aromatic compound (eg, biphenyl, fluorene, etc.) containing two or more aromatic rings; A group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic heterocycle is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2 -Aryl alkyl groups, such as a naphthyl ethyl group, etc.) etc. are mentioned. 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 the hydrocarbon group represented by Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is substituted, examples of the substituent include a hydroxy group, a carboxy group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), an alkoxy group ( Methoxy group, ethoxy group, propoxy group, butoxy group, etc.), alkyloxycarbonyl group, and the like.

Among the above, the hydrocarbon group which may have a substituent in Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is preferably a linear or branched chain alkyl group which may have a substituent, and more preferably a straight chain alkyl group. .

However, at least one of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is a hydrocarbon group having at least a polar group.

The term "hydrocarbon group having a polar group" includes both a methylene group (-CH _2- ) constituting a hydrocarbon group substituted with a polar group, or at least one hydrogen atom constituting a hydrocarbon group substituted with a polar group.

As such a "hydrocarbon group having a polar group", a functional group represented by the following general formula (a1-p1) is preferable.

[Formula 6]

[In the formula, Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms. Ra ⁰⁸ represents a divalent linking group containing a hetero atom. Ra ⁰⁶ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms. n _p0 is an integer of 1-6.]

In the formula (a1-p1), Ra ⁰⁷ represents a divalent hydrocarbon group having 2 to 12 carbon atoms.

Ra ⁰⁷ has 2 to 12 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, further preferably 2 to 4 carbon atoms, and particularly preferably 2 carbon atoms.

The hydrocarbon group for Ra ⁰⁷ is preferably a chain or cyclic aliphatic hydrocarbon group, and more preferably a chain hydrocarbon group.

Ra ⁰⁷ is, for example, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1 , 7-diyl, octane-1,8-diyl, nonan-1,9-diyl, decan-1,10-diyl, undecane-1,11-diyl, dodecane-1,12- A linear alkanediyl group such as diyl group; Propane-1,2-diyl group, 1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4 -Branched chain monovalent diyl groups such as diyl groups; Cycloalkane diyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; Polycyclic bivalent, such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group And alicyclic hydrocarbon groups.

Among the above, an alkanediyl group is preferable, and a linear alkanediyl group is more preferable.

In the formula (a1-p1), Ra ⁰⁸ represents a divalent linking group containing a hetero atom.

Ra ⁰⁸ is, for example, -O-, -C (= O) -O-, -C (= O)-, -OC (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group.), -S-, -S (= O) _2- , -S (= O) _{And 2} -O-.

Among these, -O-, -C (= O) -O-, -C (= O)-, -OC (= O) -O- are preferred from the viewpoint of solubility in the developer, and -O-, -C (= O)-is particularly preferred.

In the formula (a1-p1), Ra ⁰⁶ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms.

The number of carbon atoms of Ra ⁰⁶ is 1 to 12, and from the viewpoint of solubility in the developer, 1 to 8 carbon atoms are preferable, 1 to 5 carbon atoms are more preferable, 1 to 3 carbon atoms are more preferable, and 1 or 2 carbon atoms are preferable. Especially preferred, 1 is most preferred.

The hydrocarbon group for Ra ⁰⁶ is a chain hydrocarbon group or a cyclic hydrocarbon group, or a hydrocarbon group obtained by combining a chain and a cyclic group.

As the chain hydrocarbon group, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n- Heptyl group, 2-ethylhexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group and the like.

The cyclic hydrocarbon group may be an alicyclic hydrocarbon group or an aromatic hydrocarbon group.

The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and as the monocyclic alicyclic hydrocarbon group, for example, a cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, or methylcyclohexyl group , Cycloalkyl groups such as dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, cycloheptyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, 2-alkyladamantan-2-yl group, 1- (adamantan-1-yl) alkan-1-yl group, And a norbornyl group, a methylnorbornyl group, and an isobornyl group.

As an aromatic hydrocarbon group, for example, a phenyl group, a naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, b And phenyl groups, phenanthryl groups, 2,6-diethylphenyl groups, and 2-methyl-6-ethylphenyl groups.

As Ra ⁰⁶ , from the point of solubility in a developer, a chain hydrocarbon group is preferable, an alkyl group is more preferable, and a linear alkyl group is more preferable.

In the formula (a1-p1), n _p0 is an integer of 1 to 6, preferably an integer of 1 to 3, 1 or 2 is more preferable, and 1 is more preferable.

Below, the specific example of the hydrocarbon group which has at least a polar group is shown.

In the following formula | equation, * is a bond hand which bonds to the quaternary carbon atom (Ya ⁰ ).

[Formula 7]

In the formula (a1-r2-r1), among Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ , the number of hydrocarbon groups having at least a polar group is one or more, but considering solubility to a developer in forming a resist pattern It may be determined as appropriate, and for example, one or two of Ra ⁰³¹ , Ra ⁰³² and Ra ⁰³³ is preferable, and particularly preferably one.

The hydrocarbon group having at least the polar group may have a substituent other than the polar group. As this substituent, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), a C1-C5 halogenated alkyl group is mentioned, for example.

Equation (a1-r2-1) of, Ra ^'11 (Ra' aliphatic cyclic group of ¹⁰ is formed together with the carbon atoms bonded), the formula (a1-r-1) Ra ' of the single ring ^3-type group of the Or a group raised as an aliphatic hydrocarbon group having a polycyclic group is preferable.

In the formula (a1-r2-2), as the cyclic hydrocarbon group Xa forms together with Ya, the cyclic monovalent hydrocarbon group in the Ra ' ³ in the formula (a1-r-1) (aliphatic hydrocarbon) The group which further removed 1 or more hydrogen atoms from group) is mentioned.

The cyclic hydrocarbon group that Xa forms together with Ya may have a substituent. The substituent is, those similar to the substituent which may have a hydrocarbon cyclic in the Ra ^'3.

In formula (a1-r2-2), as Ra ⁰¹ to Ra ⁰³ , a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, Hexyl group, heptyl group, octyl group, decyl group, etc. are mentioned.

Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in Ra ⁰¹ to Ra ⁰³ include, for example, a cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooc Monocyclic aliphatic saturated hydrocarbon groups such as a til group, a cyclodecyl group, and a cyclododecyl group; Bicyclo [2.2.2] octanyl group, tricyclo [5.2.1.02,6] decanyl group, tricyclo [3.3.1.13,7] decanyl group, tetracyclo [6.2.1.13,6.02,7] dodecanyl group, ah And polycyclic aliphatic saturated hydrocarbon groups such as a damantyl group.

Ra ⁰¹ to Ra ⁰³ are preferably a hydrogen atom or a C 1 to C 10 monovalent chain saturated hydrocarbon group from the viewpoint of ease of synthesis of the monomer compound that induces the structural unit (a1), and among them, a hydrogen atom , A methyl group and an ethyl group are more preferable, and a hydrogen atom is particularly preferable.

As a substituent which the chain saturated hydrocarbon group represented by said Ra ⁰¹ -Ra ⁰³ or an aliphatic cyclic saturated hydrocarbon group has, the same group as Ra ⁰⁵ mentioned above is mentioned, for example.

As a group containing a carbon-carbon double bond formed by two or more of Ra ⁰¹ to Ra ⁰³ bonding with each other to form a cyclic structure, for example, a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, methyl And cyclohexenyl groups, cyclopentylidene etenyl groups, and cyclohexylidene etenyl groups. Among these, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylideneethenyl group are preferable from the viewpoint of the ease of synthesis of the monomer compound that leads to the structural unit (a1).

In formula (a1-r2-3), the aliphatic cyclic group Xaa forms together with Yaa is a group raised as a monocyclic group of Ra ' ³ in formula (a1-r-1) or an aliphatic hydrocarbon group as a polycyclic group. desirable.

In formula (a1-r2-3), examples of the aromatic hydrocarbon group for Ra ⁰⁴ include groups in which one or more hydrogen atoms are removed from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Especially, Ra ⁰⁴ is a group in which one or more hydrogen atoms are removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, and a group in which one or more hydrogen atoms are removed from benzene, naphthalene, anthracene or phenanthrene is more preferable, and benzene, A group in which one or more hydrogen atoms are removed from naphthalene or anthracene is more preferable, a group in which one or more hydrogen atoms are removed from benzene or naphthalene is particularly preferred, and a group in which one or more hydrogen atoms are removed from benzene is most preferred.

As a substituent which Ra ⁰⁴ in Formula (a1-r2-3) may have, for example, a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), And an alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, etc.), alkyloxycarbonyl group, and the like.

Equation (a1-r2-4) of, Ra is ^'12 and Ra' ^13, each independently, a monovalent chain-like saturated hydrocarbon group or a hydrogen atom of 1 to 10 carbon atoms. The monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra ^'12 and Ra' ¹³ is the same as the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms in Ra ⁰¹ to Ra ⁰³ . Can be. Some or all of the hydrogen atoms in the chain-saturated hydrocarbon group may be substituted.

Ra ^'12 and Ra' ¹³ are particularly preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

When the chain-saturated hydrocarbon group represented by Ra ^'12 and Ra' ¹³ is substituted, examples of the substituent include the same groups as Ra ⁰⁵ described above.

, Ra ^'14 in the formula (a1-r2-4) is a hydrocarbon group which may have a substituent. Ra 'may be the hydrocarbon group in ¹⁴ is linear or branched alkyl group, or a cyclic hydrocarbon group of.

Ra 'group of a linear at the ^14, the number of carbon atoms is 1 to 5, it is the preferred, more preferred, 1 or 2, more preferably 1-4. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, methyl group, ethyl group or n-butyl group is preferable, and methyl group or ethyl group is more preferable.

Ra 'alkyl group branched at the ^14, it is preferable that the carbon number is 3-10, more preferably 3-5. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned, and it is an isopropyl group It is preferred.

When the hydrocarbon groups of Ra ^'14 is annular, and the hydrocarbon group, aliphatic hydrocarbon contribution is contribution being an aromatic hydrocarbon, again, is the contribution polycyclic and monocyclic contribution.

As a monocyclic aliphatic hydrocarbon group, a group in which one hydrogen atom is removed from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane.

As the aliphatic hydrocarbon group having a polycyclic group, a group in which one hydrogen atom is removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, and iso And bornan, tricyclodecane, and tetracyclododecane.

Ra 'aromatic hydrocarbon group in the ^14, there may be mentioned the same aromatic hydrocarbon group in Ra ^04. In particular, Ra ^'14, the removal of one or more hydrogen atoms from an aromatic hydrocarbon ring having 6 to 15 group is preferable, and more preferable group is removed more than one hydrogen atom from benzene, naphthalene, anthracene or phenanthrene, and benzene , A group in which one or more hydrogen atoms have been removed from naphthalene or anthracene is more preferred, a group in which one or more hydrogen atoms have been removed from naphthalene or anthracene is particularly preferred, and a group in which one or more hydrogen atoms have been removed from naphthalene is most preferred.

With Ra ^'14 substituents, which may have is, those similar to the substituents that may have a ⁰⁴ Ra.

Wherein Ra ^'14 when a naphthyl group, the position in combination with a tertiary carbon atom in the formula (a1-r2-4), the first position or second position of the naphthyl group in (a1-r2-4) You can be anywhere.

Equation (a1-r2-4) of Ra ^'14 when the anthryl group, the position in combination with a tertiary carbon atom in the formula (a1-r2-4) is not 1-position of casting reel group, a 2-position Alternatively, any of the 9 positions may be used.

The specific example of the group represented by said formula (a1-r2-1) is given below.

[Formula 8]

[Formula 9]

[Formula 10]

The specific example of the group represented by said formula (a1-r2-2) is given below.

[Formula 11]

[Formula 12]

[Formula 13]

The specific example of the group represented by said formula (a1-r2-3) is given below.

[Formula 14]

The specific example of the group represented by said formula (a1-r2-4) is given below.

[Formula 15]

Tertiary alkyloxycarbonyl acid dissociative groups:

As the acid dissociable group protecting the hydroxyl group among the polar groups, for example, an acid dissociable group represented by the following general formula (a1-r-3) (hereinafter referred to as "tertiary alkyloxycarbonyl acid dissociable group" for convenience) There are).

[Formula 16]

[In the formula, Ra ' ⁷ to Ra' ⁹ are each alkyl groups.]

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

Moreover, it is preferable that carbon number of the total of each alkyl group is 3-7, it is more preferable that it is 3-5 carbon atoms, and it is most preferable that it is 3-4 carbon atoms.

As the structural unit (a1), a hydrogen atom bonded to a carbon atom at the α position may be substituted with a substituent, a structural unit derived from an acrylic acid ester, a structural unit derived from acrylamide, or a component derived from hydroxystyrene or a hydroxystyrene derivative Hydrogen in -C (= O) -OH of a structural unit derived from a vinylbenzoic acid or vinylbenzoic acid derivative, wherein at least a part of the hydrogen atom in the hydroxyl group of the unit is protected by a substituent containing the acid-decomposable group And structural units protected by a substituent in which at least a part of the atoms contain the acid-decomposable group.

As the structural unit (a1), among the above, a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α position may be substituted with a substituent is preferable.

As a preferable specific example of such a structural unit (a1), the structural unit represented by the following general formula (a1-1) or (a1-2) is mentioned.

[Formula 17]

[In formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. Va ¹ is a divalent hydrocarbon group which may have an ether bond. n _a1 is an integer of 0-2. Ra ¹ is an acid dissociable group represented by the general formula (a1-r-1) or (a1-r-2). Wa ¹ is n _a2 + monovalent hydrocarbon group, n _a2 is an integer of 1 to 3, and Ra ² is an acid dissociable group represented by the above general formula (a1-r-1) or (a1-r-3). ]

In the formula (a1-1), an alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically, methyl group, ethyl group, propyl group, isopropyl Group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.

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 from the ease of industrial availability, a hydrogen atom or a methyl group is most preferred.

In the formula (a1-1), the divalent hydrocarbon group in Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

The aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is preferably saturated.

As the aliphatic hydrocarbon group, more specifically, a straight-chain or branched-chain aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure can be given.

The straight chain aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As a linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH _2- ], an ethylene group [-(CH ₂ ) _2- ], a trimethylene group [-( And CH ₂ ) _3- ], tetramethylene group [-(CH ₂ ) _4- ], and pentamethylene group [-(CH ₂ ) _5- ].

The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.

As a branched-chain aliphatic hydrocarbon group, a branched-chain alkylene group is preferable, and specifically, -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, -C (CH ₃ ) _2- , Alkyl methylene groups such as -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _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- , -C (CH ₂ CH ₃ ) alkyl ethylene groups such as ₂ -CH _2- ; Alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH _2- ; And an alkylalkylene group such as an alkyltetramethylene group such as -CH (CH ₃ ) CH ₂ CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ CH _2- , and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

As the aliphatic hydrocarbon group containing a ring in the above structure, an alicyclic hydrocarbon group (a group in which two hydrogen atoms are removed from an aliphatic hydrocarbon ring) and an alicyclic hydrocarbon group are bonded to the ends of a linear or branched chain aliphatic hydrocarbon group. And a group interposed in the middle of an alicyclic hydrocarbon group in a straight chain or branched chain aliphatic hydrocarbon group. Examples of the straight chain or branched chain aliphatic hydrocarbon group include the same as the straight chain aliphatic hydrocarbon group or the branched chain aliphatic hydrocarbon group.

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

The alicyclic hydrocarbon group may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms are removed from monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms are removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, and iso And bornan, tricyclodecane, and tetracyclododecane.

The aromatic hydrocarbon group as a divalent hydrocarbon group in Va ¹ is a hydrocarbon group having an aromatic ring.

The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 12 carbon atoms. However, it is assumed that the carbon number in the substituent is not included in the carbon number.

As an aromatic ring which an aromatic hydrocarbon group has, specifically, aromatic hydrocarbon rings, such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene; And aromatic hetero rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned.

Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms are removed from the aromatic hydrocarbon ring (arylene group); A group in which one hydrogen atom of a group (aryl group) in which one hydrogen atom has been removed from the aromatic hydrocarbon ring is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group) , A group in which one additional hydrogen atom has been removed from an aryl group in an arylalkyl group such as 1-naphthylethyl group and 2-naphthylethyl group). 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.

In the formula (a1-1), Ra ¹ is an acid dissociable group represented by the formula (a1-r-1) or (a1-r-2).

In the formula (a1-2), the n _a2 + monovalent hydrocarbon group in Wa ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, and may be saturated or unsaturated, and is preferably saturated. The aliphatic hydrocarbon group is a combination of a straight-chain or branched-chain aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, or a straight-chain or branched chain aliphatic hydrocarbon group and an aliphatic hydrocarbon group containing a ring in the structure. One can be lifted.

As for the said _a2 + 1 value, 2-4 valence is preferable and 2 or 3 valence is more preferable.

In the formula (a1-2), Ra ² is an acid dissociable group represented by the general formula (a1-r-1) or (a1-r-3).

Below, the specific example of the structural unit represented by said formula (a1-1) is shown. In the following formulas, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

[Formula 22]

[Formula 23]

[Formula 24]

[Formula 25]

[Formula 26]

[Formula 27]

[Formula 28]

Below, the specific example of the structural unit represented by said Formula (a1-2) is shown.

[Formula 29]

The structural unit (a1) possessed by the component (A1) may be one type or two or more types.

As the structural unit (a1), the structural unit represented by the formula (a1-1) is more preferable because the characteristics (sensitivity, CDU, shape, etc.) in lithography by KrF are more easily increased.

Especially, as a structural unit (a1), it is especially preferable to include the structural unit represented by the following general formula (a1-1-1).

[Formula 30]

[In the formula, Ra ^{1 "} is an acid dissociable group represented by general formulas (a1-r2-1), (a1-r2-3) or (a1-r2-4).]

In the formula (a1-1-1), R, Va n ¹ and _a1 is the same as R, ¹ and Va n _a1 in the formula (a1-1).

The description of the acid dissociable group represented by the general formulas (a1-r2-1), (a1-r2-3) or (a1-r2-4) is as described above.

The proportion of the structural unit (a1) in the component (A1) is preferably 1 to 80 mol%, more preferably 5 to 70 mol%, with respect to the total (100 mol%) of all the structural units constituting the component (A1). It is preferable, and 10 to 60 mol% is more preferable.

By setting the ratio of the structural unit (a1) to a lower limit or higher, lithography characteristics such as sensitivity, resolution, and roughness improvement are improved. Moreover, if it is below an upper limit, it can balance with other structural units, and various lithography characteristics will become favorable.

≪Constituent unit containing hydroxystyrene skeleton (a10) ≫

It is preferable that (A1) component has a structural unit (a10) containing a hydroxystyrene skeleton in addition to the structural unit (a1).

As such a structural unit (a10), the structural unit represented by the following general formula (a10-1) is mentioned preferably, for example.

[Formula 31]

[In formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. Ya ^x1 is a single bond or a divalent linking group. Wa ^x1 is a (n _ax1 + 1) valent aromatic hydrocarbon group. n _ax1 is an integer of 1-3.]

In said formula (a10-1), R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group.

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, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl Group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The halogenated alkyl group having 1 to 5 carbon atoms in R is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.

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 from the ease of industrial availability, a hydrogen atom or a methyl group is most preferred.

In the formula (a10-1), Ya ^x1 is a single bond or a divalent linking group.

Examples of the divalent linking group in Ya ^x1 include, for example, a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom.

Divalent hydrocarbon group which may have a substituent:

When Ya ^x1 is a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

・ The aliphatic hydrocarbon group in Ya ^x1

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

Examples of the aliphatic hydrocarbon group include a straight-chain or branched-chain aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure.

A straight-chain or branched-chain aliphatic hydrocarbon group

The straight-chain aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.

As a linear aliphatic hydrocarbon group, a linear alkylene group is preferable, specifically, a methylene group [-CH _2- ], an ethylene group [-(CH ₂ ) _2- ], a trimethylene group [-( And CH ₂ ) _3- ], tetramethylene group [-(CH ₂ ) _4- ], and pentamethylene group [-(CH ₂ ) _5- ].

The branched-chain aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.

As a branched-chain aliphatic hydrocarbon group, a branched-chain alkylene group is preferable, and specifically, -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, -C (CH ₃ ) _2- , Alkyl methylene groups such as -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _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- , -C (CH ₂ CH ₃ ) alkyl ethylene groups such as ₂ -CH _2- ; Alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH _2- ; And an alkylalkylene group such as an alkyltetramethylene group such as -CH (CH ₃ ) CH ₂ CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ CH _2- , and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

The linear or branched chain 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, a carbonyl group, and the like.

An aliphatic hydrocarbon group containing a ring in the structure

As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group (a group in which two hydrogen atoms are removed from an aliphatic hydrocarbon ring) which may include a substituent containing a hetero atom in the ring structure, the cyclic aliphatic The group which the hydrocarbon group couple | bonded to the terminal of the linear or branched-chain aliphatic hydrocarbon group, the group etc. which the said cyclic aliphatic hydrocarbon group interposed in the middle of a linear or branched-chain aliphatic hydrocarbon group etc. are mentioned. The thing similar to the above is mentioned as said linear or branched-chain aliphatic hydrocarbon group.

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 contribution or a monocyclic contribution. As the monocyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms are removed from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms are removed from polycycloalkane is preferable, and as the polycycloalkane, preferably 7 to 12 carbon atoms, specifically adamantane, norbornane, And isobornane, tricyclodecane, and tetracyclododecane.

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, ethyl group, propyl group, n-butyl group, or 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, an n-butoxy group, or a tert-butoxy group, Time, an 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 a group in which part or all of the hydrogen atoms of the alkyl group are substituted with the halogen atom.

The cyclic aliphatic hydrocarbon group may be partially substituted with a substituent containing a hetero atom in a part of the carbon atoms constituting the ring structure. As a substituent containing the hetero atom, -O-, -C (= O) -O-, -S-, -S (= O) _2- , -S (= O) ₂ -O- are preferable. .

Aromatic hydrocarbon group in Ya ^x1

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

The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4 n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. However, it is assumed that the carbon number in the substituent is not included in the carbon number. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; And aromatic hetero rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. A pyridine ring, a thiophene ring, etc. are mentioned specifically, as an aromatic heterocycle.

Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms are removed from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); A group in which two hydrogen atoms are removed from an aromatic compound (eg, biphenyl, fluorene, etc.) containing two or more aromatic rings; A group in which one hydrogen atom of a group (aryl group or heteroaryl group) in which one hydrogen atom is removed from the aromatic hydrocarbon ring or aromatic hetero ring is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, 1-naph And groups having one more hydrogen atom removed from an aryl group in an arylalkyl group such as a tilmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group). The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

The aromatic hydrocarbon group may be substituted with a hydrogen atom of the aromatic hydrocarbon group as a substituent. For example, the hydrogen atom bonded to the 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, ethyl group, propyl group, n-butyl group, or tert-butyl group.

As an alkoxy group, a halogen atom, and a halogenated alkyl group as said substituent, what was illustrated as a substituent which substitutes the hydrogen atom which the said cyclic aliphatic hydrocarbon group has is mentioned.

Divalent linking group containing a hetero atom:

When Ya ^x1 is a divalent linking group containing a hetero atom, preferred as the linking group are -O-, -C (= O) -O-, -C (= O)-, -OC (= O) -O -, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group.), -S-, -S ( = O) _2- , -S (= O) ₂ -O-, general 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 ) Group represented by 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 from 0 to 3.] And the like.

The divalent linking group containing the hetero atom is -C (= O) -NH-, -C (= O) -NH-C (= O)-, -NH-, -NH-C (= NH)- In that case, the H may be substituted with a substituent such as an alkyl group or an acyl. 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.

General 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 -among, Y ²¹ and Y ²² are each independently It is a divalent hydrocarbon group which may have a substituent, and the bivalent hydrocarbon group is the same as that described in the description as the divalent linking group (divalent hydrocarbon group which may have a substituent).

As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, and a C1-C5 linear alkylene group is more preferable, and a methylene group or an ethylene group is particularly preferable.

As Y ²² , a straight-chain or branched-chain aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group, or an alkylmethylene group is more preferable. The alkyl group in the alkylmethylene group is preferably a linear alkyl group 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 from 0 to 3, preferably an integer from 0 to 2, more preferably 0 or 1 And 1 is particularly preferable. In short, 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- . The group represented by the formula-(CH ₂ ) _{a '} -C (= O) -O- (CH ₂ ) _b' -is preferable, wherein a 'is an integer from 1 to 10, and is 1 to 8 An integer is preferred, an integer from 1 to 5 is more preferred, 1 or 2 is more preferred, and 1 is most preferred, b 'is an integer from 1 to 10, an integer from 1 to 8 is preferred, 1 The integer of -5 is more preferable, 1 or 2 is still more preferable, and 1 is the most preferable.

Ya ^x1 is a single bond, an ester bond [-C (= O) -O-], an ether bond (-O-), -C (= O) -NH-, a straight chain or branched chain alkylene group, Or it is preferable that it is a combination of these, and especially, a single bond is more preferable.

In the formula (a10-1), Wa ^x1 is a (n _ax1 + 1) valent aromatic hydrocarbon group.

The aromatic hydrocarbon group for Wa ^x1 includes a group in which (n _ax1 + 1) hydrogen atoms are removed from the aromatic ring. The aromatic ring here is not particularly limited as long as it is a cyclic conjugate system having 4n + 2 π electrons, and may be monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, further preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene and phenanthrene; And aromatic hetero rings in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a hetero atom. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned. A pyridine ring, a thiophene ring, etc. are mentioned specifically, as an aromatic heterocycle.

In the formula (a10-1), n _ax1 is an integer of 1 to 3, 1 or 2 is preferable, and 1 is more preferable.

Below, the specific example of the structural unit represented by said general formula (a10-1) is shown.

In the following formulae, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[Formula 32]

The structural unit (a10) of the component (A1) may be one type or two or more types.

The proportion of the structural unit (a10) in the component (A1) is, for example, 1 to 90 mol%, based on the total (100 mol%) of all the structural units constituting the component (A1), and is 10 to 85 Molar% is preferable, 20 to 80 mol% is more preferable, and 30 to 75 mol% is particularly preferable.

By setting the proportion of the structural unit (a10) to be lower than or equal to the lower limit of the preferred range, lithography characteristics such as sensitivity, resolution, and roughness improvement are improved. Moreover, if it is below an upper limit, it can balance with other structural units, and various lithography characteristics will become favorable.

≪Composition unit (a2) ≫

The component (A1), in addition to the structural unit (a1), further comprises a structural unit (a2) containing a lactone-containing cyclic group, a -SO ₂ -containing cyclic group, or a carbonate-containing cyclic group (however, the structural unit ( a1).

The lactone-containing cyclic group, -SO ₂ -containing cyclic group, or carbonate-containing cyclic group of the structural unit (a2) is used to increase the adhesion of the resist film to the substrate when the component (A1) is used to form the resist film. It is valid. Moreover, by having the structural unit (a2), for example, the acid diffusion length is appropriately adjusted, the adhesion of the resist film to the substrate is improved, and lithography characteristics and the like are good by effects such as appropriately adjusting the solubility during development. Becomes

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

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

[Formula 33]

[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 group or 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 oxygen atom (-O-) or a sulfur atom (-S-) C1-C5 alkylene group which may contain, oxygen atom or sulfur atom, n 'is an integer of 0-2, m' is 0 or 1.]

In the general formula (a2-r-1) ~ (a2-r-7), the alkyl group in Ra ^'21 is an alkyl group having 1 to 6 carbon atoms are preferred. It is preferable that the alkyl group is linear or branched chain. Specifically, a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group and the like can be mentioned. Among these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.

Ra 'The alkoxy group in ²¹ is preferably an alkoxy group having 1 to 6 carbon atoms. It is preferable that the alkoxy group is linear or branched chain. Specific examples include an alkyl group and is either an oxygen atom (-O-) in the alkyl group as the Ra ^'21 is connected.

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 the ^{Ra '21 -COOR ", -OC (} = O) R" in, R "is a hydrogen atom, an alkyl group, a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ - containing cyclic It is Ki.

As the alkyl group for R ", any of straight chain, branched chain, and cyclic may be used, and the number of carbon atoms is preferably 1 to 15.

When R "is a straight or branched chain alkyl group, it is preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and particularly preferably a methyl group or an ethyl group.

When R "is a cyclic alkyl group, it is preferably 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, substitution with a fluorine atom or a fluorinated alkyl group A group in which one or more hydrogen atoms are removed from monocycloalkanes which may or may not be used; groups in which one or more hydrogen atoms are removed from polycycloalkanes such as bicycloalkane, tricycloalkane and tetracycloalkane, etc. More specifically, a group in which one or more hydrogen atoms are removed from monocycloalkanes such as cyclopentane and cyclohexane; adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. And groups in which one or more hydrogen atoms have been removed from polycycloalkane.

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

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

R "-SO ₂ of the-containing cyclic groups include, -SO _2, which will be described later-containing the same cyclic group, and specifically, in each of formulas (a5-r-1) ~ (a5-r-4) The group represented is mentioned.

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

In the general formulas (a2-r-2), (a2-r-3) and (a2-r-5), the alkylene group having 1 to 5 carbon atoms in A "is a straight chain or branched chain. The alkylene group is preferable, and examples thereof include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, etc. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include the alkylene group. And a group in which -O- or -S- is interposed between the terminal or the carbon atom, for example, -O-CH _2- , -CH ₂ -O-CH _2- , -S-CH ₂ -,- CH ₂ -S-CH ₂ -etc. As A ", an alkylene group having 1 to 5 carbon atoms or -O- is preferable, an alkylene group having 1 to 5 carbon atoms is more preferable, and a methylene group is most preferred. .

Below, specific examples of the groups represented by the general formulas (a2-r-1) to (a2-r-7) are given.

[Formula 34]

[Formula 35]

The "-SO ₂ -containing cyclic group" refers to a cyclic group containing a ring containing -SO ₂ -in its ring skeleton, specifically, the sulfur atom (S) in -SO ₂ -is a ring It is a cyclic group forming part of the ring skeleton of the cyclic group. The ring containing -SO ₂ -in the ring skeleton is counted as the first ring, and if it is only the ring, it is referred to as a monocyclic group, and when having another ring structure, it is referred to as a polycyclic group regardless of the structure. The -SO ₂ -containing cyclic group may be a monocyclic contribution or a polycyclic contribution.

-SO ₂ - containing cyclic group, in particular, -O-SO ₂ in the ring skeleton-type ring containing group, i.e. -O-SO ₂ - -OS- a sultone (sultone which forms part of the ring skeleton of ) It is preferable that it is a cyclic group containing a ring.

As the -SO ₂ -containing cyclic group, more specifically, groups represented by the following general formulas (a5-r-1) to (a5-r-4) are mentioned.

[Formula 36]

[Wherein, Ra ^'51 is each 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" is an alkyl having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom. It is a ren group, an oxygen atom, or a sulfur atom, and n 'is an integer of 0-2.]

In the general formulas (a5-r-1) to (a5-r-2), A "is the general formulas (a2-r-2), (a2-r-3), (a2-r-5) It is the same as A "in.

As the alkyl group, alkoxy group, halogen atom, halogenated alkyl group, -COOR ", -OC (= O) R" and hydroxyalkyl group for Ra ^'51 , the above-mentioned general formulas (a2-r-1) to (a2), respectively. -r-7) it can be given in the same as in the description for all Ra ^'21.

Below, specific examples of the groups represented by general formulas (a5-r-1) to (a5-r-4) are given. "Ac" in the formula represents an acetyl group.

[Formula 37]

[Formula 38]

[Formula 39]

The "carbonate-containing cyclic group" refers to a cyclic group containing a ring (carbonate ring) containing -O-C (= O) -O- in the ring skeleton. The carbonate ring is counted as the first ring, and if it is only a carbonate ring, it is referred to as a monocyclic group, and when having another ring structure, it is referred to as a polycyclic group regardless of its structure. The carbonate-containing cyclic group may be a monocyclic contribution or a polycyclic contribution.

The carbonate ring-containing cyclic group is not particularly limited and any one can be used. Specifically, groups represented by the following general formulas (ax3-r-1) to (ax3-r-3) are exemplified.

[Formula 40]

[Wherein, Ra ' ^x31 is each 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" is an alkyl having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom. A len group, an oxygen atom or a sulfur atom, p 'is an integer from 0 to 3, and q' is 0 or 1.]

In the general formulas (ax3-r-2) to (ax3-r-3), A "is the general formulas (a2-r-2), (a2-r-3), (a2-r-5) It is the same as A "in.

Ra ^'31 alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR in ", -OC (= O) R ", a hydroxyl group, each of the above general formula (a2-r-1) ~ (a2 -r-7) it can be given in the same as in the description for all Ra ^'21.

Below, specific examples of the groups represented by the general formulas (ax3-r-1) to (ax3-r-3) are given.

[Formula 41]

Especially as a structural unit (a2), the structural unit derived from the acrylic acid ester which may be substituted with the substituent by the hydrogen atom couple | bonded with the carbon atom of the (alpha) position is preferable.

It is preferable that such a structural unit (a2) is a structural unit represented by the following general formula (a2-1).

[Formula 42]

[Wherein, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. Ya ²¹ is a single bond or a divalent linking group. La ²¹ is -O-, -COO-, -CON (R ')-, -OCO-, -CONHCO- or -CONHCS-, and R' represents a hydrogen atom or a methyl group. However, when La ²¹ is -O-, Ya ²¹ does not become -CO-. Ra ²¹ is a lactone-containing cyclic group, a carbonate-containing cyclic group, or a -SO ₂ -containing cyclic group.]

In the formula (a2-1), R is as defined above. 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 from the ease of industrial availability, a hydrogen atom or a methyl group is particularly preferable.

In the formula (a2-1), the divalent linking group of Ya ²¹ is not particularly limited, and a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a hetero atom, and the like are preferably mentioned. The description of the divalent hydrocarbon group which may have a substituent in Ya ²¹ and a divalent linking group containing a hetero atom may be obtained in Ya ^x1 in the general formula (a10-1) described above. It is the same as the description of the divalent hydrocarbon group and the divalent linking group containing a hetero atom.

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 carbonate-containing cyclic group.

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

Among them, lactone-containing cyclic groups or -SO ₂ -containing cyclic groups are preferable, and the general formulas (a2-r-1), (a2-r-2), (a2-r-6) or (a5- Each group represented by r-1) is more preferable. Specifically, the above formulas (r-lc-1-1) to (r-lc-1-7), (r-lc-2-1) to (r-lc-2-18), (r-lc -6-1), (r-sl-1-1), (r-sl-1-18) Each group represented by each is more preferable.

The structural unit (a2) of the component (A1) may be one type or two or more types.

(A1) When a component has a structural unit (a2), the ratio of the structural unit (a2) is 0-50 mol% with respect to the sum (100 mol%) of all the structural units which comprise the said (A1) component. It is preferable, it is more preferable that it is 5 to 45 mol%, it is more preferable that it is 10 to 40 mol%, and it is especially preferable that it is 10 to 30 mol%.

By setting the ratio of the structural unit (a2) to a preferable lower limit or higher, the effect by containing the structural unit (a2) is sufficiently obtained. It becomes good.

≪Composition unit (a3) ≫

The component (A1) is, in addition to the structural unit (a1), further a structural unit (a3) containing a polar group-containing aliphatic hydrocarbon group (however, except for the structural unit (a1) and structural unit (a2)) You may have When the component (A1) has the structural unit (a3), for example, the acid diffusion length is appropriately adjusted, the adhesion of the resist film to the substrate is improved, the solubility during development is appropriately adjusted, the etching resistance is improved, etc. By the effect of, lithography characteristics and the like are improved.

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

Examples of the aliphatic hydrocarbon group include a straight-chain or branched-chain hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a cyclic aliphatic hydrocarbon group (cyclic group). As the cyclic group, either a monocyclic contribution or a polycyclic contribution may be obtained, and, for example, a resin for a resist composition for an ArF excimer laser, can be suitably selected and used from among many proposed ones. The cyclic group is preferably a polycyclic group, and more preferably 7 to 30 carbon atoms.

Especially, the structural unit derived from the acrylic acid ester containing the aliphatic polycyclic group containing the hydroxyalkyl group in which a part of the hydrogen atom of a hydroxyl group, a cyano group, a carboxy group, or an alkyl group was substituted with the fluorine atom is more preferable. Examples of the polycyclic group include a group in which two or more hydrogen atoms are removed from bicycloalkane, tricycloalkane, tetracycloalkane, or the like. Specifically, groups in which two or more hydrogen atoms have been removed from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane are mentioned. Among these polycyclic groups, a group in which two or more hydrogen atoms are removed from adamantane, a group in which two or more hydrogen atoms are removed from norbornane, and a group in which two or more hydrogen atoms are removed from tetracyclododecane are industrially preferred.

As a structural unit (a3), if it contains a polar group containing aliphatic hydrocarbon group, arbitrary thing can be used without being specifically limited.

As the structural unit (a3), a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α position may be substituted with a substituent is preferably a structural unit containing a polar group-containing aliphatic hydrocarbon group.

As a structural unit (a3), when the hydrocarbon group in a polar group-containing aliphatic hydrocarbon group is a C1-C10 linear or branched-chain hydrocarbon group, the structural unit derived from hydroxyethyl ester of acrylic acid is preferable.

Moreover, as a structural unit (a3), when the hydrocarbon group in a polar group-containing aliphatic hydrocarbon group is a polycyclic group, the structural unit represented by following formula (a3-1), the structural unit represented by formula (a3-2), formula ( The structural unit represented by a3-3) is mentioned as a preferable thing.

[Formula 43]

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

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

It is preferable that j is 1, and it is especially preferable that a hydroxyl group couple | bonds with the 3 position of adamantyl group.

In formula (a3-2), it is preferable that k is 1. It is preferable that the cyano group is bonded to the 5 or 6 position of the norbornyl group.

In formula (a3-3), it is preferable that t 'is 1. It is preferable that l is 1. It is preferable that s is 1. It is preferable that 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 5 or 6 position of the norbornyl group.

The structural unit (a3) possessed by the component (A1) may be one type or two or more types.

(A1) When a component has a structural unit (a3), it is preferable that it is 1-40 mol% with respect to the total of the total structural unit which comprises the said (A1) component, 2-30 mol% is more preferable, and 5 -25 mol% is more preferable, and 5-20 mol% is particularly preferable.

By setting the ratio of the structural unit (a3) to a preferable lower limit or higher, an effect by containing the structural unit (a3) is sufficiently obtained, and if it is lower than or equal to the upper limit, it can be balanced with other structural units, and various lithographic properties It becomes good.

≪Constituent unit (st) ≫

(A1) A component may have the structural unit (st) derived from styrene or its derivative further in addition to a structural unit (a1). "Styrene" is a concept including styrene and those in which the hydrogen atom at the α-position of styrene is substituted with a substituent such as an alkyl group or a halogenated alkyl group. The alkyl group as the substituent here includes an alkyl group having 1 to 5 carbon atoms, and the halogenated alkyl group as the substituent group includes a halogenated alkyl group having 1 to 5 carbon atoms.

Examples of the "styrene derivative" include a substituent bonded to a benzene ring of styrene in which the hydrogen atom at the α position may be substituted with a substituent.

Note that the α position (the carbon atom at the α position) refers to a carbon atom to which the benzene ring is attached, unless otherwise specified.

"Structural units derived from styrene" and "structural units derived from styrene derivatives" refer to structural units formed by cleavage of ethylenic double bonds of styrene or styrene derivatives.

The structural unit (st) possessed by the component (A1) may be one type or two or more types.

(A1) When a component has a structural unit (st), the ratio of the structural unit (st) is 1-50 mol% with respect to the total (100 mol%) of all the structural units which comprise the (A1) component It is preferable, and it is more preferable that it is 3-40 mol%.

≪Other structural units≫

(A1) A component may have other structural units other than the structural unit (a1), structural unit (a10), structural unit (a2), structural unit (a3), and structural unit (st) mentioned above.

As other structural unit, for example, the structural unit (a9) represented by general formula (a9-1) mentioned later, the structural unit derived from styrene, and the structural unit derived from a styrene derivative (however, to structural unit (a10)) And the structural unit containing an acid non-aliphatic aliphatic cyclic group.

Constituent unit (a9):

The structural unit (a9) is a structural unit represented by the following general formula (a9-1).

[Formula 44]

[In formula, R is a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 halogenated alkyl group. Ya ⁹¹ is a single bond or a divalent linking group. Ya ⁹² is a divalent linking group. R ⁹¹ is a hydrocarbon group which may have a substituent.]

In the formula (a9-1), R is as defined above.

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 from the ease of industrial availability, a hydrogen atom or a methyl group is particularly preferable.

In the formula (a9-1), the divalent linking group in Ya ⁹¹ may be the same as the divalent linking group in Ya ^x1 in the general formula (a10-1) described above. Especially, it is preferable that it is a single bond as Ya ⁹¹ .

In the formula (a9-1), the divalent linking group in Ya ⁹² may be the same as the divalent linking group in Ya ^{x1 in} the general formula (a10-1) described above.

In the divalent linking group for Ya ⁹² , the divalent hydrocarbon group which may have a substituent is preferably a linear or branched aliphatic hydrocarbon group.

Moreover, in the divalent linking group in Ya ⁹² , as a divalent linking group containing a hetero atom, -O-, -C (= O) -O-, -C (= O)-, -OC (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group.), -S- , -S (= O) _2- , -S (= O) ₂ -O-, -C (= S)-, general 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 -or -Y ²¹ -OC (= O) -Y ^Groups represented by ^22- [wherein, Y ²¹ and Y ²² each independently represent a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m 'is an integer from 0 to 3]. have. Especially, -C (= O)-and -C (= S)-are preferable.

In the formula (a9-1), examples of the hydrocarbon group for R ⁹¹ include an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, and an aralkyl group.

The alkyl group for R ⁹¹ preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and may be either linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, etc. are mentioned as a preferable thing.

The monovalent alicyclic hydrocarbon group for R ⁹¹ is preferably 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms, and may be polycyclic or monocyclic. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms are removed from monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclobutane, cyclopentane, and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms are removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, And isobornane, tricyclodecane, and tetracyclododecane.

The aryl group for R ⁹¹ is preferably 6 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, and particularly preferably a phenyl group.

To an aralkyl group in R ⁹¹ is an "aryl group in R ^91," an aralkyl group is bonded alkylene group and the group having 1 to 8 carbon atoms is preferable, according to an alkylene group wherein the "R ⁹¹ having 1 to 6 carbon atoms The aralkyl group to which the "aryl group of" is bonded is more preferable, and the aralkyl group to which the alkylene group having 1 to 4 carbon atoms and the "aryl group in R ⁹¹ " are bonded is particularly preferable.

The hydrocarbon group for R ⁹¹ preferably has some or all of the hydrogen atoms of the hydrocarbon group substituted with fluorine atoms, and more preferably 30 to 100% of the hydrogen atoms of the hydrocarbon group substituted with fluorine atoms. Especially, it is especially preferable that all the hydrogen atoms of the above-mentioned alkyl group are perfluoroalkyl groups substituted with fluorine atoms.

The hydrocarbon group for R ⁹¹ may have a substituent. Examples of the substituent include halogen atom, oxo group (= O), hydroxyl group (-OH), amino group (-NH ₂ ), -SO ₂ -NH ₂ and the like. Moreover, a part of the carbon atoms constituting the hydrocarbon group may be substituted with a substituent containing a hetero atom. As a substituent containing the hetero atom, -O-, -NH-, -N =, -C (= O) -O-, -S-, -S (= O) _2- , -S (= O ) ₂ -O-.

In R ⁹¹ , examples of the hydrocarbon group having a substituent include lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), respectively.

In addition, in R ^91, the hydrocarbon group having a substituent, -SO ₂ each represent by the general formula (a5-r-1) ~ (a5-r-4) - containing cyclic group; Substituted aryl groups represented by the following formula, monovalent heterocyclic groups, and the like can also be mentioned.

[Formula 45]

Among the structural units (a9), structural units represented by the following general formula (a9-1-1) are preferable.

[Formula 46]

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

In general formula (a9-1-1), description of Ya ⁹¹ , R ⁹¹ , and R is the same as described above. Moreover, R ⁹² is an oxygen atom or a sulfur atom.

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

[Formula 47]

[Formula 48]

[Formula 49]

The structural unit (a9) contained in the component (A1) may be one type or two or more types.

(A1) When a component has a structural unit (a9), the ratio of the structural unit (a9) is 1-40 mol% with respect to the total (100 mol%) of all the structural units which comprise the (A1) component It is preferable, 3 to 30 mol% is more preferable, 5 to 25 mol% is more preferable, and 10 to 20 mol% is particularly preferable.

By setting the ratio of the structural unit (a9) to the lower limit or higher, for example, the acid diffusion length is appropriately adjusted, the adhesion of the resist film to the substrate is improved, the solubility during development is appropriately adjusted, and the etching resistance is improved. When is obtained and is equal to or less than the upper limit, it can be balanced with other structural units, and various lithographic characteristics are improved.

Constituent unit (a4):

The structural unit (a4) is a structural unit containing an acid non-aliphatic aliphatic cyclic group. (A1) A component may have a structural unit (a4) in addition to a structural unit (a1).

When the component (A1) has a structural unit (a4), the dry etching resistance of the resist pattern to be formed is improved. Moreover, the hydrophobicity of (A) component becomes high. It is thought that the improvement of hydrophobicity contributes to the improvement of resolution, resist pattern shape, etc., especially in the case of a solvent development process.

The "acid-non-cyclic cyclic group" in the structural unit (a4) is the acid when the acid is generated in the resist composition by exposure (for example, when the acid is generated from the component (B) described later). It is a cyclic group that remains in the structural unit without dissociation even if it acts.

As the structural unit (a4), for example, a structural unit derived from an acrylic acid ester containing an acid non-aliphatic aliphatic cyclic group or the like is preferable. The cyclic group is used for a resin component of a resist composition such as for an ArF excimer laser, for a KrF excimer laser (preferably for an ArF excimer laser), and a number of conventionally known ones can be used.

Particularly, at least one species selected from tricyclodecyl group, adamantyl group, tetracyclododecyl group, isobornyl group, norbornyl group is preferable in view of being easy to obtain industrially. These polycyclic groups may have a C1-C5 linear or branched chain alkyl group as a substituent.

As the structural unit (a4), specifically, structural units represented by the following general formulas (a4-1) to (a4-7) can be exemplified.

[Formula 50]

[Wherein, R ^α is as defined above.]

(A1) The structural unit (a4) which a component has may be 1 type, or 2 or more types may be sufficient as it.

(A1) When a component has a structural unit (a4), it is preferable that the ratio of the structural unit (a4) is 1-30 mol% with respect to the total of all the structural units which comprise the component (A1), and is 3- 20 mol% is more preferable.

By setting the ratio of the structural unit (a4) to a preferable lower limit or higher, the effect by containing the structural unit (a4) is sufficiently obtained, while by setting the ratio to the lower limit or higher, it is easy to balance the other structural units.

As the component (A1) contained in the resist composition, one type may be used alone, or two or more types may be used in combination.

It is preferable that (A1) component contains the high molecular compound (A1-1) which has a structural unit (a1) (it is also hereafter referred to as "(A1-1) component").

As a preferable (A1-1) component, For example, the polymer compound which has a repeating structure of a structural unit (a1) and a structural unit (a10), and a polymer which has a repeating structure of a structural unit (a1) and a structural unit (st) And compounds.

In addition to the combination of the above two respective structural units, as the third or three or more structural units, the above-described structural units may be appropriately combined according to desired effects. Examples of the combination of three or more structural units include a combination of the structural unit (a1), the structural unit (a10), and the structural unit (st).

In the component (A1), a monomer inducing each structural unit is dissolved in a polymerization solvent, and, for example, azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate (for example, V-601, etc.) It can be produced by adding a radical polymerization initiator such as) to polymerize. Alternatively, such a component (A1) polymerizes a monomer (a monomer in which functional groups of the monomer are protected) of a monomer inducing a structural unit (a1) and a monomer inducing a structural unit other than the structural unit (a1) as necessary. It can be produced by dissolving in a solvent, adding a radical polymerization initiator as described above to polymerize, and then performing a deprotection reaction. Further, during polymerization, for example, by using a chain transfer agent such as HS-CH ₂ -CH ₂ -CH ₂ -C (CF ₃ ) ₂ -OH in combination, -C (CF ₃ ) ₂ -OH at the terminal. You may introduce a flag. As described above, the copolymer in which a hydroxyalkyl group in which a part of the hydrogen atom of the alkyl group is substituted with a fluorine atom is introduced is effective in reducing development defects and reducing LER (line edge roughness: uneven irregularities on the line sidewalls).

The mass average molecular weight (Mw) of the component (A1) (based on polystyrene conversion by gel permeation chromatography (GPC)) is not particularly limited, preferably from 1000 to 50000, more preferably from 2000 to 30000, and 3000 -20000 is more preferable.

When the Mw of the component (A1) is equal to or less than the preferred upper limit of this range, there is sufficient solubility in the resist solvent for use as a resist, and if it is equal to or higher than the preferred lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good .

The dispersion degree (Mw / Mn) of the component (A1) is not particularly limited, and 1.0 to 4.0 is preferable, 1.0 to 3.0 is more preferable, and 1.1 to 2.0 is particularly preferable. In addition, Mn represents the number average molecular weight.

・ About (A2) ingredient

The resist composition of the present embodiment is a component (A), which does not correspond to the component (A1), and a base component whose solubility in a developer is changed by the action of an acid (hereinafter referred to as "(A2) component"). You may use together.

(A2) As a component, it is not specifically limited, As a base component for chemically amplified resist compositions, you may select and use arbitrarily from many conventionally known ones.

(A2) As a component, you may use individually by 1 type of a high molecular compound or a low molecular compound, or you may use it in combination of 2 or more type.

The proportion of the component (A1) in the component (A) is preferably 25% by mass or more, more preferably 50% by mass or more, even more preferably 75% by mass or more, with respect to the total mass of the component (A), 100 It may be mass%. When the ratio is 25% by mass or more, a resist pattern excellent in various lithography characteristics such as high sensitivity, resolution, and roughness improvement is liable to be formed.

<Component (Z)>

In the resist composition of the present embodiment, the component (Z) is a dissolution preventing agent that suppresses solubility in a developer.

The component (Z) has a mass average molecular weight of 3000 or less, a compound having a phenolic hydroxyl group or a carboxyl group in the molecule (Z1) (hereinafter also referred to as a "(Z1) component"), and a mass average molecular weight of 3000 or less, Moreover, the compound (Z2) represented by General formula (z2) mentioned later (it is also hereafter referred to as "(Z2) component") is included.

・ About (Z1) component

The (Z1) component is not particularly limited as long as the compound has a mass average molecular weight of 3000 or less and has a phenolic hydroxyl group or a carboxyl group in the molecule.

The mass average molecular weight of the (Z1) component is preferably 150 to 3000, more preferably 200 to 2500, and even more preferably 250 to 2000.

When the mass average molecular weight of the (Z1) component is equal to or more than the lower limit of the preferred range, substrate adhesion performance is improved.

As a component (Z1), the compound represented by the following general formula (z1-1) or (z1-2) is preferable.

[Formula 51]

[In formula (z1-1), V _z ¹ is a divalent linking group. In the formula (z1-2), R _z ¹⁰ is a polycyclic alicyclic hydrocarbon group which may have a substituent or an aromatic hydrocarbon group which may have a substituent. n11 and n12 are each independently an integer of 1-3. In the formula (z2-1), Rz ² is a hydrocarbon group. n21 is 1 or 2. n22 is an integer of 2-5. However, n21 + n22 ≤ 6.]

In the formula (z1-1), examples of the divalent linking group of V _z ^{1 include} the same as the divalent linking group in Ya ^x1 in the general formula (a10-1) described above. Moreover, as the divalent linking group of V _z ¹ , a part of the hydrogen atoms constituting the straight-chain or branched-chain aliphatic hydrocarbon group as the divalent linking group in Ya ^x1 in the general formula (a10-1) described above is used. And groups substituted with aromatic hydrocarbon groups.

The linear or branched-chain aliphatic hydrocarbon group in the "group in which a part of the hydrogen atoms constituting the straight-chain or branched-chain aliphatic hydrocarbon group is substituted with an aromatic hydrocarbon group" is a methylene group [-CH _2- ] , Ethylene group [-(CH ₂ ) _2- ], -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, -C (CH ₃ ) _2- , -C (CH ₃ ) (CH ₂ CH _{And 3} )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, and -C (CH ₂ CH ₃ ) _2- .

The aromatic hydrocarbon group in the "group in which a part of hydrogen atoms constituting a linear or branched chain aliphatic hydrocarbon group is substituted with an aromatic hydrocarbon group" includes benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and the like. And groups in which one hydrogen atom has been removed from the aromatic ring.

The aromatic hydrocarbon group in the "group in which a part of hydrogen atoms constituting a linear or branched chain aliphatic hydrocarbon group is substituted with an aromatic hydrocarbon group" may 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 an arylalkyl group.

The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, ethyl group, propyl group, n-butyl group, or tert-butyl group.

Examples of the alkoxy group, the halogen atom, and the halogenated alkyl group as the substituent include a divalent linking group in Ya ^x1 in the general formula (a10-1) described above, as a substituent that substitutes a hydrogen atom in a cyclic aliphatic hydrocarbon group. What was illustrated is mentioned.

Examples of the arylalkyl group as the substituent include a benzyl group, a phenethyl group, a phenyl-t-butyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, and a 2-naphthylethyl group. The arylalkyl group may have a substituent such as an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, or an arylalkyl group.

As the compound represented by the formula (z1-1), a compound represented by the following general formula (z1-1-1) is preferable.

[Formula 52]

[Wherein, R _z ¹¹ and R _z ¹² are each independently a hydrogen atom or a hydrocarbon group which may have a substituent. R _z ¹¹ and R _z ¹² may combine with each other to form a ring. n11 and n12 are each independently an integer of 1-3.]

In the formula (z1-1-1), examples of the hydrocarbon group for R _z ¹¹ and R _z ¹² include a linear or branched chain alkyl group, an aromatic hydrocarbon group which may have a substituent, and the like.

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. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned. Among these, methyl group, ethyl group or n-butyl group is preferable, and methyl group or ethyl group is more preferable.

The branched chain alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned, and it is an isopropyl group It is preferred.

Examples of the aromatic hydrocarbon group for R _z ¹¹ and R _z ¹² include a group in which one hydrogen atom has been removed from aromatic rings such as benzene, fluorene, naphthalene, anthracene, phenanthrene, and biphenyl.

The aromatic hydrocarbon group for R _z ¹¹ and R _z ¹² may have a substituent. The substituent is the same as the substituent which the aromatic hydrocarbon group may have in the above-mentioned "group in which a part of hydrogen atoms constituting a straight-chain or branched-chain aliphatic hydrocarbon group is substituted with an aromatic hydrocarbon group".

In the formula (z1-1-1), R _z ¹¹ and R _z ¹² may combine with each other to form a ring. Examples of the formed ring include aliphatic rings such as cyclopentane ring, cyclohexane ring, and cycloheptane ring.

In the formula (z1-1-1), R _z ¹¹ and R _z ¹² are an aromatic hydrocarbon group which may have a C1-C5 linear alkyl group or a substituent, or R _z ¹¹ and R _z ¹² It is preferable to combine with each other to form an aliphatic ring, or a methyl group, a phenyl group, or a 4- (4-hydroxyphenyl-t-butyl) phenyl group, or R _z ¹¹ and R _z ¹² may combine with each other to form a cyclopentane ring. It is more preferable to form.

In the formula (z1-2), examples of the hydrocarbon group of Rz ² include those exemplified as the hydrocarbon groups of R _z ¹¹ and R _z ¹² in the formula (z1-1-1). Of these, roneun Rz ^2, the aromatic hydrocarbon group is preferable, and a phenyl or benzyl group is more preferred, and more preferred is phenyl group.

In the formula (z1-2), n21 is 1 or 2, and 1 is preferable. n22 is an integer of 2-5, 2 or 3 is preferable, and 2 is more preferable.

As the compound represented by the formula (z1-2), a compound represented by the following general formula (z1-2-1) is preferable.

[Formula 53]

[In the formula, Rz ²¹ and Rz ²² are each independently an aromatic hydrocarbon group.]

In the formula (z1-2-1), examples of the hydrocarbon group of Rz ² include those exemplified as the hydrocarbon groups of R _z ¹¹ and R _z ¹² in the formula (z1-1-1). Among them, roneun Rz ^2, or a phenyl group, and benzyl group is preferable, more preferably a phenyl group.

Below, the specific example of (Z1) component is given.

[Formula 54]

(Z1) As another specific example of the component, the compound described in paragraph [0158] of JP 2008-122932 A, the compound described in paragraphs [0036]-[0055] of JP 10-097075 A And compounds.

As the component (Z1) contained in the resist composition, one type may be used alone, or two or more types may be used in combination.

・ About (Z2) component

(Z2) A component is a compound whose mass average molecular weight is 3000 or less, and is represented by the following general formula (z2).

[Formula 55]

[Wherein, R _z ²⁰ is an acid dissociative group. R _z ³⁰ is a hydrogen atom or an organic group. n1 is an integer of 1-6, n2 is an integer of 0-5. However, n1 + n2 = 6.]

The mass average molecular weight of the (Z2) component is preferably 150 to 3000, more preferably 200 to 2500, further preferably 250 to 2000.

When the mass average molecular weight of the (Z2) component is within the above-mentioned preferred range, the amount of reduction in the resist film made of the radiation-sensitive resin composition can be reduced.

In the formula (z2), examples of the acid dissociable group of R _z ²⁰ include groups represented by the following general formulas (z2-r-1) to (z2-r-4).

[Formula 56]

[Wherein, R _z ²⁰¹ to R _z ²⁰⁶ are each independently a straight or branched alkyl group, a straight or branched alkoxy group, a straight or branched alkoxyalkyl group, a straight chain or It is a branched alkenyl group or an aryl group, and these groups may contain a carbonyl group in the chain. Alternatively, R _z ²⁰¹ and R _z ²⁰² , R _z ²⁰⁴ and R _z ²⁰⁵ may be bonded to each other to form a ring. R _z ²⁰⁷ and R _z ²⁰⁸ are each independently a hydrogen atom, a straight-chain or branched alkyl group, a straight-chain or branched alkoxy group, a straight-chain or branched alkoxyalkyl group, a straight-chain or branched It is an alkenyl group or an aryl group. R _z ²⁰⁹ is a straight-chain or branched alkyl group, a straight-chain or branched alkoxyalkyl group, a straight-chain or branched alkenyl group, or an aryl group, and these groups may contain a carbonyl group in the chain. Alternatively, R _z ²⁰⁹ may be bonded to R _z ²⁰⁸ to form a ring. R _z ²¹⁰ is a divalent aliphatic, alicyclic or aromatic group, and R _z ²¹¹ is an acid dissociable group. q is 0 or 1.]

In the formulas (z2-r-1) to (z2-r-2), R _z ²⁰¹ to R _z ²⁰⁶ are each independently a straight-chain or branched alkyl group, a straight-chain or branched alkoxy group. , A straight-chain or branched alkoxyalkyl group, a straight-chain or branched alkenyl group, or an aryl group, and these groups may contain a carbonyl group in the chain.

Examples of the alkyl group for R _z ²⁰¹ to R _z ²⁰⁶ include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, hexyl and cyclohexyl groups , Adamantyl groups, and the like, preferably having 1 to 10 carbon atoms, and among them, methyl group, ethyl group, isopropyl group, and tert-butyl group are more preferably used.

Examples of the alkoxy group in R _z ²⁰¹ to R _z ²⁰⁶ include, for example, methoxy group, ethoxy group, propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, and hexyloxy group. , Cyclohexyloxy groups, etc., preferably having 1 to 8 carbon atoms, among them, methoxy groups, ethoxy groups, isopropoxy groups, and tert-butoxy groups are more preferably used.

As the alkoxyalkyl group for R _z ²⁰¹ to R _z ²⁰⁶ , for example, those having 2 to 10 carbon atoms such as methoxymethyl group, ethoxypropyl group, propoxyethyl group, and tert-butoxyethyl group are preferable, and among them, A methoxymethyl group, methoxyethyl group, ethoxypropyl group, propoxyethyl group, etc. are preferable.

As the alkenyl group in R _z ²⁰¹ to R _z ²⁰⁶ , those having 2 to 4 carbon atoms such as vinyl group, propenyl group, allyl group and butenyl group are preferable.

The aryl group in R _z ²⁰¹ to R _z ²⁰⁶ preferably has 6 to 14 carbon atoms such as a phenyl group, a xylyl group, a toluyl group, and a cumenyl group.

In the formulas (z2-r-1) to (z2-r-2), R _z ²⁰¹ and R _z ²⁰² , R _z ²⁰⁴ and R _z ²⁰⁵ may be bonded to each other to form a ring.

As a ring formed by R ^z201 and R _z ²⁰² being bonded to each other, for example, a carbon number of 4 to 4 such as cyclohexylidene group, cyclopentylidene group, 3-oxocyclohexylidene group, 4-methylcyclohexylidene group, etc. There are 10 things.

Examples of the ring formed by R _z ²⁰⁴ and R _z ²⁰⁵ bonding with each other include, for example, 1-silacyclohexylidene group, 1-silacyclopentylidene group, 3-oxo-1-silacyclopentylidene group, 4- And 3 to 9 carbon atoms such as methyl-1-silacyclopentylidene group.

In the formula (z2-r-3), R _z ²⁰⁷ and R _z ²⁰⁸ are each independently a hydrogen atom, a straight-chain or branched alkyl group, a straight-chain or branched alkoxy group, a straight-chain or It is a branched alkoxyalkyl group, a linear or branched alkenyl group, or an aryl group. R _z ²⁰⁹ is a straight-chain or branched alkyl group, a straight-chain or branched alkoxyalkyl group, a straight-chain or branched alkenyl group, or an aryl group, and these groups may contain a carbonyl group in the chain.

The alkyl group, alkoxy group, alkoxyalkyl group, alkenyl group and aryl group in R _z ²⁰⁷ to R _z ²⁰⁹ are used for R _z ²⁰¹ to R _z ²⁰⁶ in the formulas (z2-r-1) to (z2-r-2). It is the same as the alkyl group, alkoxy group, alkoxyalkyl group, alkenyl group and aryl group.

In the formula (z2-r-3), R _z ²⁰⁹ may combine with R _z ²⁰⁸ to form a ring.

As a ring formed by R _z ²⁰⁹ bonding with R _z ²⁰⁸ , for example, carbon number 4 such as 2-oxacyclohexylidene group, 2-oxacyclopentylidene group, 2-oxa-4-methylcyclohexylidene group, etc. The thing of -10 is mentioned.

In the formula (z2-r-4), R _z ²¹⁰ is a divalent aliphatic, alicyclic or aromatic group.

The divalent aliphatic group for R _z ²¹⁰ is preferably 1 to 8 carbon atoms such as methylene group, ethylene group, propylene group, butylene group, 2-methylpropylene group, and 2-methyl-3-ethoxybutylene group. , Especially, a methylene group, an ethylene group, and a propylene group are more preferably used.

Examples of the divalent alicyclic group in R _z ²¹⁰ include those having 5 to 10 carbon atoms such as cyclohexylene group.

Examples of the divalent aromatic group for R _z ²¹⁰ include those having 6 to 14 carbon atoms such as a phenylene group, a xylylene group, a toluylene group, and a cumenylene group.

In the formula (z2-r-4), examples of the acid dissociable group for R _z ²¹¹ include groups represented by the formulas (z2-r-1) to (z2-r-3).

In the formula (z2), R _z ³⁰ is a hydrogen atom or an organic group.

The organic group of R _z ³⁰ includes a hydrocarbon group which may have a substituent.

Examples of the hydrocarbon group for R _z ³⁰ include a linear or branched chain alkyl group or a cyclic hydrocarbon group.

The straight-chain alkyl group in R _z ³⁰ preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specifically, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, etc. are mentioned.

The branched chain alkyl group for R _z ³⁰ preferably has 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms. Specifically, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, 1,1-diethylpropyl group, 2,2-dimethylbutyl group, etc. are mentioned.

The cyclic hydrocarbon group in R _z ³⁰ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may also be polycyclic or monocyclic.

As a monocyclic aliphatic hydrocarbon group, a group in which one hydrogen atom is removed from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane.

As the aliphatic hydrocarbon group having a polycyclic group, a group in which one hydrogen atom is removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically adamantane, norbornane, and iso And bornan, tricyclodecane, and tetracyclododecane.

Examples of the aromatic hydrocarbon group for R _z ³⁰ include a group in which one hydrogen atom is removed from aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; A group in which one hydrogen atom is removed from an aromatic heterocycle such as a pyridine ring or a thiophene ring; A group in which one hydrogen atom has been removed from an aromatic compound (eg, biphenyl, fluorene, etc.) containing two or more aromatic rings; A group in which one of the hydrogen atoms of the aromatic hydrocarbon ring or aromatic hetero ring is substituted with an alkyl group (for example, a benzyl group, a phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2- Arylalkyl groups such as naphthylethyl group) and the like. The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

As a substituent which the hydrocarbon group in R _z ³⁰ may have, a straight-chain, branched-chain or cyclic alkyl group, aromatic hydrocarbon group, straight-chain or branched-chain alkoxy group, hydroxyl group, carboxy group, halogen atom And groups represented by the formulas (z2-r-1) to (z2-r-4). The aromatic hydrocarbon group as a substituent which the hydrocarbon group in R _z ³⁰ may have is a linear, branched chain, or cyclic alkyl group, or the formulas (z2-r-1) to (z2-r-4) described above. ).

As the component (Z2), at least one member selected from the group consisting of groups represented by the following general formulas (z2-1) to (z2-2) is preferable.

[Formula 57]

[Wherein, V _z ² is a divalent linking group. R _z ²⁰ and R _z ³³ are each independently an acid dissociative group. R _z ³¹ and R _z ³² are each independently a hydrogen atom or an organic group. R _z ²⁵ and R _z ²⁶ are each independently a hydrogen atom or a hydrocarbon group which may have a substituent. n11 is an integer of 1-5. n12 is an integer of 0-4. However, n11 + n12 = 5. n13 is an integer of 1-5. n14 is an integer of 0-4. However, n11 + n12 = 5.]

In the formula (z2-1), the divalent linking group in V _z ² is the same as the divalent linking group in Ya ^x1 in the formula (a10-1). Among them, as the divalent linking group in V _z ² , a straight chain alkylene group having 1 to 10 carbon atoms is preferable, and a methylene group [-CH _2- ], an ethylene group [-(CH ₂ ) _2- ], A trimethylene group [-(CH ₂ ) _3- ], a tetramethylene group [-(CH ₂ ) _4- ], a pentamethylene group [-(CH ₂ ) _5- ] is more preferable, and a methylene group is more preferable. .

In the formulas (z2-1) to (z2-2), the acid dissociable group in R _z ²⁰ and R _z ³³ is the same as the acid dissociable group in R _z ²⁰ in the formula (z2). Among them, R _z ^20, R _z with an acid-dissociable group in the ^33, the expression (z2-r-4) group is preferably represented by the above formula (z2-r-4) in the in the R _z ²¹¹ It is more preferable that the acid dissociable group is a group represented by the formula (z2-r-1).

In the formulas (z2-1) to (z2-2), the organic group in R _z ³¹ and R _z ³² is the same as the organic group in R _z ³⁰ in the formula (z2). Among them, the organic group in R ³¹ _{z, z} R ^32, it is more preferably a group shown to preferably an aromatic hydrocarbon which may have a substituent, and by the general formula (z2-r-5).

[Formula 58]

[Wherein, R _z ²⁰¹ is an acid dissociative group. R _z ³⁰¹ is a hydrogen atom or an alkyl group. n15 is an integer of 1-6, n16 is an integer of 0-5. However, n15 + n16 = 6. n17 is 0 or 1. * Represents a bonding hand.]

In the formula (z2-r-5), the acid dissociable group in R _z ²⁰¹ is the same as the acid dissociable group in R _z ²⁰ in formula (z2). Among them, the acid-dissociable group in the R _z ²⁰¹ is preferably a represented by the formula (z2-r-4), and the above formula (z2-r-4) acid-dissociable group in the in the R _z ²¹¹ It is more preferable that it is a group represented by said Formula (z2-r-1).

In the formula (z2-r-5), R _z ³⁰¹ is preferably a methyl group, an ethyl group, or a cyclohexyl group, and more preferably a methyl group or a cyclohexyl group.

In said formula (z2-r-5), 1 or 2 is preferable and 1 is more preferable in n15.

In said formula (z2-r-5), 4 or 5 is preferable and, as for n16, 5 is more preferable.

In the formula (z2-2), the hydrocarbon group in R _z ²⁵ and R _z ²⁶ is the same as the hydrocarbon group as the organic group in R _z ³⁰ in the formula (z2). Especially, as R _z ²⁵ and R _z ²⁶ , an aromatic hydrocarbon group which may have a hydrogen atom or a substituent is preferable, and a hydrogen atom or a group represented by the formula (z2-r-5) is more preferable.

In the formulas (z2-1) to (z2-2), n11 and n13 are preferably 1 or 2, and more preferably 1.

In said formula (z2-1)-(z2-2), 4 or 5 is preferable and, as for n16, 5 is more preferable.

Hereinafter, specific examples of the component (Z2) include compounds represented by the following formulas (Z2-1) and (Z2-2), as described in paragraphs [0046]-[0050] of JP 2005-122097 A. And compounds.

[Formula 59]

(Z2) As another specific example of the component, the compound described in paragraphs [0034], [0036] and [0037] of JP 9-278699 A, paragraphs [0119] of JP 10-097075 A ]-[0122] and the like.

As the (Z2) component contained in the resist composition, one type may be used alone, or two or more types may be used in combination.

In the resist composition of the present embodiment, the content of the (Z) component is preferably 30 parts by mass or less, and more preferably 10 to 30 parts by mass with respect to 100 parts by mass of the component (A).

When the proportion of the (Z) component is within the range of the above-mentioned preferred range, etching resistance is good, and it is easy to form a pattern of good shape.

Moreover, in the resist composition of this embodiment, it is preferable that the compounding ratio (mass ratio) of the (Z1) component and the (Z2) component in the (Z) component is Z1: Z2 = 75: 25 to 25:75, and Z1: Z2 = 70: 30 to 40: 60 is more preferable, and Z1: Z2 = 67: 33 to 45: 55 is more preferable.

When the compounding ratio (mass ratio) of the (Z1) component and the (Z2) component in the (Z) component is within the range of the above-described preferred range, etching resistance is good and a pattern having a good shape is easily formed.

<Random ingredients>

≪ (B) component: acid generator component≫

It is preferable that the resist composition of this embodiment contains the acid generator component ((B) component) which generates an acid by exposure in addition to (A) component and (Z) component.

(B) As a component, it is not specifically limited, So far, what has been proposed as an acid generator for chemically amplified resist compositions can be used.

Examples of such acid generators include onium salt-based acid generators such as iodonium salts and sulfonium salts, and oxime sulfonate-based acid generators; Diazomethane-based acid generators such as bisalkyl or bisarylsulfonyldiazomethanes and poly (bissulfonyl) diazomethanes; And nitrobenzyl sulfonate-based acid generators, iminosulfonate-based acid generators, and disulfone-based acid generators.

Examples of the onium salt-based acid generator include compounds represented by the following general formula (b-1) (hereinafter also referred to as "(b-1) component") and compounds represented by the general formula (b-2) (hereinafter "( b-2) component ”or a compound represented by general formula (b-3) (hereinafter also referred to as“ (b-3) component ”).

[Formula 60]

[Wherein, R ¹⁰¹ , R ¹⁰⁴ to R ¹⁰⁸ are each independently a cyclic group which may have a substituent, a chained alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. R ¹⁰⁴ and R ¹⁰⁵ may be bonded to each other to form a ring. R ¹⁰² is a fluorine atom or a C1-C5 fluorinated alkyl group. 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 are each independently a single bond or an oxygen atom. L ¹⁰³ to L ¹⁰⁵ are each independently a single bond, -CO- or -SO _2- . m is an integer greater than or equal to 1, and M'm ⁺ is an orthovalent cation of m value.]

{Noonbu}

・ (B-1) Anion part of component

In formula (b-1), R ¹⁰¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

Cyclic groups 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. Moreover, aliphatic hydrocarbon group may be saturated or unsaturated, and it is preferable that it is usually saturated.

The aromatic hydrocarbon group for R ¹⁰¹ is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. . However, it is assumed that the carbon number in the substituent is not included in the carbon number.

As an aromatic ring of the aromatic hydrocarbon group in R ¹⁰¹ , specifically, benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocycle in which a part of the carbon atoms constituting these aromatic rings is substituted with a hetero atom And the like. As a hetero atom in an aromatic heterocyclic ring, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned.

Specifically as the aromatic hydrocarbon group for R ¹⁰¹ , a group in which one hydrogen atom is removed from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, etc.), and one of the hydrogen atoms in the aromatic ring is an alkylene group And substituted groups (eg, arylalkyl groups such as benzyl, phenethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, and 2-naphthylethyl). 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 carbon atoms, and particularly preferably 1 carbon atom.

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

As the aliphatic hydrocarbon group containing a ring in this structure, an alicyclic hydrocarbon group (a group in which one hydrogen atom is removed from an aliphatic hydrocarbon ring) and an alicyclic hydrocarbon group are bonded to the ends of a straight-chain or branched-chain aliphatic hydrocarbon group. And a group interposed in the middle of an alicyclic hydrocarbon group in a straight chain or branched chain aliphatic hydrocarbon group.

The alicyclic hydrocarbon group preferably has 3 to 30 carbon atoms, more preferably 3 to 20 carbon atoms.

The alicyclic hydrocarbon group may be a polycyclic contribution or a monocyclic contribution. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms are removed from monocycloalkane is preferable. As the monocycloalkane, those having 3 to 6 carbon atoms are preferable, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms are removed from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, the polycycloalkanes include polycycloalkanes having a polycyclic skeleton of a crosslinked ring system such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane; A polycycloalkane having a condensed cyclic polycyclic skeleton such as a cyclic group having a steroid skeleton is more preferable.

Especially, as the cyclic aliphatic hydrocarbon group for R ¹⁰¹ , a group in which one or more hydrogen atoms are removed from monocycloalkane or polycycloalkane is preferable, and a group in which one hydrogen atom is removed from polycycloalkane is more preferable, Adamantyl group, norbornyl group, cyclic group having a steroid skeleton is particularly preferred, adamantyl group, cyclic group having a steroid skeleton is most preferred.

The straight-chain or branched-chain aliphatic hydrocarbon group, which may be bonded to an alicyclic hydrocarbon group, preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and more preferably 1 carbon atom. -3 is particularly preferable.

As a linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [-CH _2- ], an ethylene group [-(CH ₂ ) _2- ], a trimethylene group [-( And CH ₂ ) _3- ], tetramethylene group [-(CH ₂ ) _4- ], and pentamethylene group [-(CH ₂ ) _5- ].

As a branched-chain aliphatic hydrocarbon group, a branched-chain alkylene group is preferable, and specifically, -CH (CH ₃ )-, -CH (CH ₂ CH ₃ )-, -C (CH ₃ ) _2- , Alkyl methylene groups such as -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _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- , -C (CH ₂ CH ₃ ) alkyl ethylene groups such as ₂ -CH _2- ; Alkyltrimethylene groups such as -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH _2- ; And an alkylalkylene group such as an alkyltetramethylene group such as -CH (CH ₃ ) CH ₂ CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ CH _2- , and the like. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Moreover, the cyclic hydrocarbon group in R ¹⁰¹ may contain a hetero atom like a heterocycle. Specifically, the lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), respectively, as the general formulas (a5-r-1) to (a5-r-4). And -SO ₂ -containing cyclic groups, respectively, and heterocyclic groups represented by the following formulas (r-hr-1) to (r-hr-16), respectively.

[Formula 61]

As a substituent in the cyclic group of R ¹⁰¹ , an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, etc. are mentioned, for example.

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

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, an n-butoxy group, or a tert-butoxy group, , Ethoxy group is most preferred.

A fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned as a halogen atom as a substituent, 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, for example, a group in which part or all of hydrogen atoms such as methyl group, ethyl group, propyl group, n-butyl group and tert-butyl group are substituted with the halogen atom. have.

The carbonyl group as a substituent is a group that substitutes a methylene group (-CH _2- ) constituting a cyclic hydrocarbon group.

Chain type alkyl group which may have a substituent:

The chain alkyl group of R ¹⁰¹ may be either straight chain or branched chain.

As a linear alkyl group, it is preferable that it has 1-20 carbon atoms, it is more preferable that it is 1-15 carbon atoms, and most preferably 1-10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group , Tetradecyl group, pentadecyl group, hexadecyl group, isohexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, henicosyl group, docosyl group and the like.

The branched chain alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2 -Ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, and the like.

Chain type alkenyl group which may have a substituent:

The chain alkenyl group of R ¹⁰¹ may be either a straight chain or a branched chain, preferably 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, and even more preferably 2 to 4 carbon atoms. And 3 carbon atoms is particularly preferable. As a linear alkenyl group, vinyl group, propenyl group (allyl group), butynyl group etc. are mentioned, for example. As a branched chain alkenyl group, 1-methylvinyl group, 2-methylvinyl group, 1-methylpropenyl group, 2-methylpropenyl group, etc. are mentioned, for example.

As the chain-type alkenyl group, among the above, a straight-chain alkenyl group is preferable, a vinyl group and a propenyl group are more preferable, and a vinyl group is particularly preferable.

Examples of the substituent in the chained alkyl group or alkenyl group of R ¹⁰¹ include, for example, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and a cyclic group in R ¹⁰¹ above. Can be lifted.

Especially, R ¹⁰¹ is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, a group in which one or more hydrogen atoms are removed from a phenyl group, a naphthyl group, or polycycloalkane; Lactone-containing cyclic groups represented by the general formulas (a2-r-1), (a2-r-3) to (a2-r-7), respectively; The -SO ₂ -containing cyclic groups represented by the general formulas (a5-r-1) to (a5-r-4), respectively, are preferred.

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

If the Y ¹⁰¹ 2-valent connecting group containing an oxygen atom, and Y is ^101, it may contain an atom other than an oxygen atom. As an atom other than an oxygen atom, a carbon atom, a hydrogen atom, a sulfur atom, a nitrogen atom, etc. are mentioned, for example.

Examples of the bivalent linking group containing such an oxygen atom include linking groups represented by the general formulas (y-al-1) to (y-al-8), respectively.

As Y ¹⁰¹ , a divalent linking group containing an ester bond or a divalent linking group containing an ether bond is preferable, and linking groups represented by the general formulas (y-al-1) to (y-al-5) are more preferred. desirable.

In the formula (b-1), V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group. It is preferable that the alkylene group and fluorinated alkylene group in V ¹⁰¹ 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. Especially, it is preferable that V ¹⁰¹ is a single bond or a C1-C4 fluorinated alkylene group.

In said formula (b-1), R ¹⁰² is a fluorine atom or a C1-C5 fluorinated alkyl group. R ¹⁰² is preferably a fluorine atom or a C 1 to C 5 perfluoroalkyl group, and more preferably a fluorine atom.

(b-1) As a specific example of the anion part of a component, when Y ¹⁰¹ becomes a single bond, fluorinated alkyl sulfo, such as trifluoromethanesulfonate anion and perfluorobutanesulfonate anion, for example Nate anion; When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, anions represented by any of the following formulas (an-1) to (an-3) can be exemplified.

[Formula 62]

[Wherein, R " ¹⁰¹ has an aliphatic cyclic group which may have a substituent, a monovalent heterocyclic group represented by the above formulas (r-hr-1) to (r-hr-6), or a substituent R < ¹⁰² is an aliphatic cyclic group which may have a substituent, and is represented by the general formulas (a2-r-1) and (a2-r-3) to (a2-r-7). represent each a lactone-containing cyclic group, or the formula (a5-r-1) ~ (a5-r-4) each represent -SO ₂ -, a group containing a cyclic. R " ¹⁰³ is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl group which may have a substituent.

V " ¹⁰¹ is a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. V" is each independently 0 ∼ 3, q "is each independently an integer of 1 to 20, and n" is 0 or 1.]

To R ^"101, R" ¹⁰² and R "import ¹⁰³ the substituent in Fig cyclic that group, the group exemplified as the aliphatic hydrocarbon group of annular in the R ¹⁰¹ are preferable. In the above substituents, R ¹⁰¹ The same thing as the substituent which may substitute the cyclic aliphatic hydrocarbon group in the above is mentioned.

R ^"103 aromatic cyclic which may have a substituent in the groups, it is preferred that due exemplified as the aromatic hydrocarbon group in groups hydrocarbons, cyclic in the above-mentioned R ^101. As the substituent of the R ¹⁰¹ The same thing as the substituent which may substitute the aromatic hydrocarbon group is mentioned.

R "group of the chain which may have a substituent in the ^101, is due exemplified as the alkyl group of the chain-like in the above-mentioned R ¹⁰¹ is preferable. R" ¹⁰⁴ Al of chain which may have a substituent in the it is alkenyl group, a group exemplified as the alkenyl group of chain-like in the above-mentioned R ¹⁰¹ is preferred.

V " ¹⁰¹ is preferably a single bond or a fluorinated alkylene group, more preferably a single bond or a fluorinated alkylene group having 1 to 3 carbon atoms. When V" ¹⁰¹ is a fluorinated alkylene group, -V " ¹⁰¹ -C (F ) (R " ¹⁰² ) -SO ₃ -in V" ¹⁰¹ is -CF _2- , -CHF-, -CF ₂ CF _2- , -CHFCF _2- , -CF (CF ₃ ) CF ₂ -,- It is preferable that CH (CF ₃ ) CF _2- , and -CF _2- , -CHF- are more preferable.

R ¹⁰² is a fluorine atom or a C 1 to C 5 fluorinated alkyl group. R ¹⁰² is preferably a fluorine atom or a C 1 to C 5 perfluoroalkyl group, and more preferably a fluorine atom.

v "is an integer of 0-3, Preferably it is 0 or 1. q" is an integer of 1-20, Preferably it is an integer of 1-10, More preferably, it is an integer of 1-5 , More preferably 1, 2 or 3, particularly preferably 1 or 2. n "is 0 or 1.

・ (B-2) Anion part of component

In formula (b-2), R ¹⁰⁴ and R ¹⁰⁵ are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. , Respectively, the same as R ¹⁰¹ in the formula (b-1). However, R ¹⁰⁴ and R ¹⁰⁵ may combine with each other to form a ring.

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

The chain-like alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7, and more preferably 1 to 3 carbon atoms. The carbon number of the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible, for the reason that the solubility in the solvent for resist is good within the range of the carbon number. Moreover, in the chain alkyl group of R ¹⁰⁴ and R ^105, the more the number of hydrogen atoms substituted with fluorine atoms, the stronger the strength of the acid, so it is preferable. The proportion of fluorine atoms in the chain-type alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably, a perfluoroalkyl group in which all hydrogen atoms are replaced with fluorine atoms. to be.

In 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 ones as V ¹⁰¹ in formula (b-1) can be mentioned.

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

・ (B-3) Anion part of component

In formula (b-3), R ¹⁰⁶ to R ¹⁰⁸ are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent. , Respectively, the same as R ¹⁰¹ in the formula (b-1) can be mentioned.

L ¹⁰³ to L ¹⁰⁵ are each independently a single bond, -CO- or -SO _2- .

{Cation Part}

In formulas (b-1), (b-2) and (b-3), m is an integer of 1 or more, M ' ^{m +} is an m-valent onium cation, and sulfonium cation and iodonium cation are preferred. Examples thereof include organic cations represented by the general formulas (ca-1) to (ca-4).

[Formula 63]

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

Examples of the aryl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² include an aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.

The alkyl group in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² is a chain or cyclic alkyl group, and preferably has 1 to 30 carbon atoms.

The alkenyl groups in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² are preferably 2 to 10 carbon atoms.

As the substituent which R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² may have, for example, an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, the following general formula (ca-r-1) )-(Ca-r-7).

[Formula 64]

[In the formula, R ' ²⁰¹ is each independently a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.]

The cyclic group which may have a substituent of R ' ²⁰¹ , a chained alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent is the same as R ¹⁰¹ in the formula (b-1) described later. In addition to the above, examples of the cyclic group which may have a substituent or the chain-like alkyl group which may have a substituent include the same acid-dissociable group represented by the formula (a1-r-2) described above.

When R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , R ²¹¹ to R ²¹² are bonded to each other to form a ring together with the sulfur atom in the formula, a hetero atom such as a sulfur atom, an oxygen atom or a nitrogen atom, or a carbonyl group, -SO-, -SO _2- , -SO _3- , -COO-, -CONH- or -N (R _N )-(The R _N is an alkyl group having 1 to 5 carbon atoms.) You may do it. As the ring to be formed, one ring containing a sulfur atom in the formula in its ring skeleton, including a sulfur atom, is preferably a 3 to 10 membered ring, and particularly preferably a 5 to 7 membered ring. Specific examples of the formed ring include, for example, thiophene ring, thiazole ring, benzothiophene ring, thiantrene ring, benzothiophene ring, dibenzothiophene ring, 9H-thioxanthene ring, and thioxanthone Rings, thiantrene rings, phenoxatine rings, tetrahydrothiophenium rings, tetrahydrothiopyranium rings, and the like.

R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when forming an alkyl group, they may combine with each other to form a ring.

R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a -SO ₂ -containing cyclic group which may have a substituent.

Examples of the aryl group for R ²¹⁰ include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.

The alkyl group for R ²¹⁰ is a chain or cyclic alkyl group, and preferably has 1 to 30 carbon atoms.

The alkenyl group for R ²¹⁰ is preferably 2 to 10 carbon atoms. In R ²¹⁰ , as the -SO ₂ -containing cyclic group which may have a substituent, "-SO ₂ -containing polycyclic group" is preferable, and the group represented by the general formula (a5-r-1) is more preferable. Do.

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

The arylene group in Y ²⁰¹ includes a group in which one hydrogen atom is removed from the aryl group exemplified as an aromatic hydrocarbon group in R ¹⁰¹ in the formula (b-1) described later.

Examples of the alkylene group and the alkenylene group for Y ²⁰¹ include a group in which one hydrogen atom is removed from the group exemplified as a chain alkyl group or a chain alkenyl group in R ¹⁰¹ in the formula (b-1) described later. have.

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

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

As the divalent linking group in W ²⁰¹ , a divalent hydrocarbon group which may have a substituent is preferable, and a divalent hydrocarbon group which may have a substituent similar to Ya ²¹ in the general formula (a2-1) described above is exemplified. Can be. The divalent linking group in W ²⁰¹ may be any of a straight chain, a branched chain, and a cyclic form, and is preferably cyclic. Especially, a group in which two carbonyl groups are combined at both ends of an arylene group is preferable. A phenylene group, a naphthylene group, etc. are mentioned as an arylene group, and a phenylene group is especially 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.

As a preferable cation represented by said formula (ca-1), specifically, following formula (ca-1-1)-(ca-1-78), (ca-1-101)-(ca-1-149) Cation represented by each is mentioned.

In the following formula, g1 represents a repetition number, and g1 is an integer of 1-5. g2 represents the number of repetitions, and g2 is an integer of 0-20. g3 represents the number of repetitions, and g3 is an integer of 0-20.

[Formula 65]

[Formula 66]

[Formula 67]

[Formula 68]

[Formula 69]

[Formula 70]

[Formula 71]

[Formula 72]

[Formula 73]

[Formula 74]

[Wherein, R " ²⁰¹ is a hydrogen atom or a substituent. As the substituent, an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, or a carbonyl group as the substituents which R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² may have. And a group represented by a general group, an amino group, an aryl group, and general formulas (ca-r-1) to (ca-r-7).]

As a preferable cation represented by said formula (ca-2), specifically, cation, diphenyl iodonium cation, bis (4) represented by following formula (ca-2-1)-(ca-2-3), respectively. -tert-butylphenyl) iodonium cation.

[Formula 75]

As a preferable cation represented by said formula (ca-3), cation represented by following formula (ca-3-1)-(ca-3-7) respectively is specifically, mentioned.

[Formula 76]

As a preferable cation represented by said formula (ca-4), cation represented by following formula (ca-4-1)-(ca-4-2) specifically, is mentioned.

[Formula 77]

Among the above, the cation moiety ((M ^{m +} ) _{1 / m} ) is preferably a cation represented by the general formula (ca-1) or (ca-2), and the formulas (ca-1-1) to (ca-1) -78), (ca-1-101) to (ca-1-149) and cations represented by formulas (ca-2-1) to (ca-2-3), respectively, are more preferable.

As an imino sulfonate type acid generator, the compound represented by the following general formula (b-4) (it is also hereafter referred to as "(b-4) component") is mentioned.

[Formula 78]

[Wherein, R ²¹³ is an alkyl group which may have a substituent or an aryl group which may have a substituent. A is an alkylene group which may have a substituent, an alkenylene group which may have a substituent, or an arylene group which may have a substituent.]

Specific examples of the component (b-4) include compounds represented by the following formula (B1-1), compounds described in paragraphs [0089]-[0091] of JP 10-097075 A, and the like. .

[Formula 79]

In the resist composition of the present embodiment, as the component (B), one type may be used alone, or two or more types may be used in combination.

When the resist composition contains the component (B), the content of the component (B) in the resist composition is preferably 50 parts by mass or less, more preferably 0.1 to 40 parts by mass, relative to 100 parts by mass of the component (A). , 0.1 to 30 parts by mass are more preferable, and 0.1 to 20 parts by mass are particularly preferred.

Pattern formation is fully performed by making content of (B) component into the said range.

≪ (D) component≫

In addition to the (A) component and the (Z) component, the resist composition in the present embodiment may further contain an acid diffusion control agent component (hereinafter referred to as "(D) component"). The component (D) acts as a trap (acid diffusion control agent) for trapping the acid generated by exposure in the resist composition.

As the component (D), for example, a nitrogen-containing organic compound (D1) (hereinafter referred to as "(D1) component", photodecay decomposed by exposure that does not correspond to the component (D1) to lose acid diffusion controllability Sex base (D2) (hereinafter referred to as "(D2) component"); and the like.

By using the resist composition containing the component (D), when forming a resist pattern, the contrast between the exposed portion and the unexposed portion of the resist film can be further improved.

・ About (D1) ingredient

(D1) A component is a base component and is a nitrogen-containing organic compound component which acts as an acid diffusion control agent in a resist composition.

(D1) As a component, if it acts as an acid diffusion control agent, it will not specifically limit, For example, an aliphatic amine, an aromatic amine, etc. are mentioned.

The aliphatic amine is particularly preferably a secondary aliphatic amine or a tertiary aliphatic amine.

The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.

Examples of the aliphatic amine include amines (alkylamines or alkylalcoholamines) or cyclic amines 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.

Specific examples of the alkylamine and alkylalcoholamine include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; Dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; Trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri trialkylamines such as -n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; And alkyl alcohol amines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, trialkylamines having 5 to 10 carbon atoms are more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

As a cyclic amine, the heterocyclic compound containing a nitrogen atom as a hetero atom is mentioned, for example. 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, piperazine and the like.

The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and specifically, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.4.0] And -7-undecene, hexamethylenetetramine, and 1,4-diazabicyclo [2.2.2] octane.

As other aliphatic amines, tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} Amine, tris {2- (1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, Tris [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] amine, triethanolamine triacetate, and the like, and triethanolamine triacetate is preferred.

Examples of aromatic amines include 4-dimethylaminopyridine, pyrrole, indole, pyrazole, imidazole or derivatives thereof, tribenzylamine, aniline compounds, and N-tert-butoxycarbonylpyrrolidine.

(D1) A component may be used individually by 1 type, and may be used in combination of 2 or more type.

(D1) As a component, an aromatic amine is preferable among the above, and an aniline compound is more preferable. As an aniline compound, 2,6-diisopropylaniline, N, N-dimethylaniline, N, N-dibutylaniline, N, N-dihexylaniline etc. are mentioned, for example.

・ About (D2) ingredient

The component (D2) is not particularly limited as long as it is decomposed by exposure to lose acid diffusion controllability, and is a compound represented by the following general formula (d2-1) (hereinafter referred to as "(d2-1) component"). , Compound represented by the following general formula (d2-2) (hereinafter referred to as "(d2-2) component") and compounds represented by the following general formula (d2-3) (hereinafter referred to as "(d2-3) component" .) Is preferably at least one compound selected from the group consisting of.

The components (d2-1) to (d2-3) do not act as a solution because they decompose in the exposed portion of the resist film and lose acid diffusion controllability (basicity), and act as a measure in the unexposed portion of the resist film. do.

[Formula 80]

[Wherein, Rd ¹ to Rd ⁴ are cyclic groups which may have a substituent, chained alkyl groups which may have a substituent, or chained alkenyl groups which may have a substituent. However, in Rd ² in the general formula (d2-2), a fluorine atom is not bound to a carbon atom adjacent to the S atom. Yd ¹ is a single bond or a divalent linking group. m is an integer of 1 or more, and ^{M'm +} are each independently an m-valent onium cation.]

{Component (d2-1)}

· Anion

In formula (d2-1), Rd ¹ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and each of the above formula (b- The same thing as R ¹⁰¹ in 1) is mentioned.

Among these, 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 alkyl group which may have a substituent. Substituents which these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a fluorinated alkyl group, and lactone-containing cyclic groups represented by the general formulas (a2-r-1) to (a2-r-7), respectively. Groups, ether bonds, ester bonds, or combinations thereof. When an ether bond or an ester bond is included as a substituent, an alkylene group may be interposed, and as the substituent in this case, a linking group represented by the formulas (y-al-1) to (y-al-5), respectively, is preferable. Do.

The aromatic hydrocarbon group preferably includes a polycyclic structure containing a phenyl group, a naphthyl group, and a bicyclooctane skeleton (eg, a polycyclic structure composed of a bicyclooctane skeleton and a ring structure other than this). Can be.

The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

The chain alkyl group preferably has 1 to 10 carbon atoms, specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, etc. Straight-chain alkyl group; 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1-methyl And branched chain alkyl groups such as pentyl group, 2-methylpentyl group, 3-methylpentyl group, and 4-methylpentyl group.

When the chain-like alkyl group is a fluorine atom or a fluorinated alkyl group having a fluorinated alkyl group as a substituent, the number of carbon atoms of the fluorinated alkyl group is preferably 1 to 11, more preferably 1 to 8, and even more preferably 1 to 4. The fluorinated alkyl group may contain atoms other than fluorine atoms. As an atom other than a fluorine atom, an oxygen atom, a sulfur atom, a nitrogen atom, etc. are mentioned, for example.

As Rd ¹ , it is preferable that some or all of the hydrogen atoms constituting the linear alkyl group are fluorinated alkyl groups substituted with fluorine atoms, and all of the hydrogen atoms constituting the linear alkyl group are fluorinated alkyl groups substituted with fluorine atoms. It is particularly preferable that it is a (linear perfluoroalkyl group).

Preferred specific examples of the anion portion of the (d2-1) component are shown below.

[Formula 81]

· Cation

In formula (d2-1), M'm ⁺ is an m-valent onium cation.

As the onium cation of M'm ^{+, those similar to} the cations represented by the general formulas (ca-1) to (ca-4) are preferably mentioned, and the cation represented by the general formula (ca-1) is mentioned. More preferably, cations represented by the formulas (ca-1-1) to (ca-1-78) and (ca-1-101) to (ca-1-149) are more preferred.

(d2-1) A component may be used individually by 1 type, or may be used in combination of 2 or more type.

{Component (d2-2)}

· Anion

In formula (d2-2), Rd ² is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the formula (b-1) ) R ¹⁰¹ and the like.

However, in Rd ² , the fluorine atom is not bound to the carbon atom adjacent to the S atom (not fluorine substituted). Thereby, the anion of the (d2-2) component becomes an appropriate weak acid anion, and the quenching ability as the (D2) component is improved.

As Rd ² , it is preferable that it is a chain alkyl group which may have a substituent, or an aliphatic cyclic group which may have a substituent. The chain alkyl group is preferably 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. Examples of the aliphatic cyclic group include a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, etc. (may have a substituent); It is more preferable that the group is one or more hydrogen atoms removed from a camper or the like.

The hydrocarbon group of Rd ² may have a substituent, and as the substituent, a hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in Rd ¹ of the formula (d2-1) may be included. The thing same as a substituent is mentioned.

Preferred specific examples of the anion portion of the (d2-2) component are shown below.

[Formula 82]

· Cation

In formula (d2-2), M'm ⁺ is m-valent onium cation, and is the same as M'm ⁺ in formula (d2-1).

(d2-2) A component may be used individually by 1 type, or may be used in combination of 2 or more type.

{(d2-3) component}

 · Anion

In formula (d2-3), Rd ³ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the formula (b-1) is The same thing as R <^101> in this is mentioned, It is preferable that it is a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group. Especially, a fluorinated alkyl group is preferable, and the same thing as the fluorinated alkyl group of Rd ¹ is more preferable.

In formula (d2-3), Rd ⁴ is a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent, and the formula (b-1) ) R ¹⁰¹ and the like.

Especially, it is preferable that it is an alkyl group, an alkoxy group, an alkenyl group, and a cyclic group which may have a substituent.

The alkyl group for Rd ⁴ is preferably a linear or branched chain alkyl group having 1 to 5 carbon atoms, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. A part of the hydrogen atom of the alkyl group of Rd ⁴ may be substituted with a hydroxyl group, a cyano group, or the like.

The alkoxy group for Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and specifically, as the alkoxy group having 1 to 5 carbon atoms, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- And a butoxy group and a tert-butoxy group. Especially, a methoxy group and an ethoxy group are preferable.

The alkenyl group in Rd ⁴ includes the same as R ¹⁰¹ in the formula (b-1), and vinyl groups, propenyl groups (allyl groups), 1-methylpropenyl groups, and 2-methylpropenyl groups are preferred. . These groups may further have a C1-C5 alkyl group or a C1-C5 halogenated alkyl group as a substituent.

The cyclic group in Rd ⁴ includes the same as R ¹⁰¹ in the formula (b-1), and cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, and tetracyclo An alicyclic group in which one or more hydrogen atoms are removed from cycloalkanes such as dodecane 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 favorably dissolved in an organic solvent, whereby lithography properties are improved.

In formula (d2-3), Yd ¹ is a single bond or a divalent linking group.

Although it does not specifically limit as a bivalent linking group in Yd ¹ , Divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent, divalent linking group containing hetero atom, etc. are mentioned. Among these, in the description of the bivalent linking group in Ya ^x1 in the formula (a10-1), the same may be mentioned as the divalent hydrocarbon group which may have a substituent, or a divalent linking group containing a hetero atom.

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 straight chain or branched chain alkylene group, and more preferably a methylene group or an ethylene group.

Preferred specific examples of the anion portion of the (d2-3) component are shown below.

[Formula 83]

[Formula 84]

 · Cation

In formula (d2-3), M'm ⁺ is m-valent onium cation, and is the same as M'm ⁺ in formula (d2-1).

(d2-3) A component may be used individually by 1 type, or may be used in combination of 2 or more type.

As the component (D2), any one of the components (d2-1) to (d2-3) may be used, or two or more of them may be used in combination.

When the resist composition contains the component (D2), the content of the component (D2) in the resist composition is preferably 0.5 to 35 parts by mass, more preferably 1 to 25 parts by mass, relative to 100 parts by mass of the component (A) , 2 to 20 parts by mass are more preferable, and 3 to 15 parts by mass are particularly preferred.

When the content of the component (D2) is greater than or equal to a preferable lower limit, particularly good lithography properties and resist pattern shapes are likely to be obtained. On the other hand, if it is less than or equal to the upper limit, balance with other components can be achieved, and various lithography characteristics are improved.

(D2) Method of preparing the component:

The manufacturing method of the said (d2-1) component and (d2-2) component is not specifically limited, It can be manufactured by a well-known method.

Moreover, the manufacturing method of (d2-3) component is not specifically limited, For example, it manufactures by carrying out similarly to the method described in US2012-0149916.

≪Component (E): at least one compound selected from the group consisting of organic carboxylic acids and phosphorus oxo acids and derivatives thereof≫

In the resist composition of the present embodiment, for the purpose of preventing deterioration in sensitivity, improving resist pattern shape, delayed time-lapse stability, and the like, as an optional component, in the group consisting of organic carboxylic acid and phosphorus oxo acid and derivatives thereof At least one selected compound (E) (hereinafter referred to as "(E) component") can be contained.

As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are preferable.

As the oxo acid of phosphorus, phosphoric acid, phosphonic acid, phosphinic acid, etc. are mentioned, and among these, phosphonic acid is particularly preferable.

Examples of the derivative of oxo acid of phosphorus include, for example, an ester in which the hydrogen atom of oxo acid is substituted with a hydrocarbon group, and examples of the hydrocarbon group include an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 15 carbon atoms, and the like. Can be heard.

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

Examples of the 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.

As a derivative of phosphinic acid, a phosphinic acid ester, phenylphosphinic acid, etc. are mentioned.

In the resist composition of this embodiment, (E) component may be used individually by 1 type and may use 2 or more types together.

When the resist composition contains the component (E), the content of the component (E) is usually used in a range of 0.01 to 5 parts by mass relative to 100 parts by mass of the component (A).

≪ (F) component: Fluorine additive component≫

The resist composition of the present embodiment may contain a fluorine additive component (hereinafter referred to as "(F) component") in order to impart water repellency to the resist film or to improve lithography characteristics.

As the component (F), for example, Japanese Patent Application Publication No. 2010-002870, Japanese Patent Application Publication No. 2010-032994, Japanese Patent Application Publication No. 2010-277043, Japanese Patent Application Publication No. 2011-13569, Japanese Patent Application The fluorine-containing polymer compound described in 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) is exemplified. As this polymer, the polymer (homopolymer) which consists only of the structural unit (f1) represented by following formula (f1-1); A copolymer of the structural unit (f1) and the structural unit (a1); It is preferable that it is a copolymer of the structural unit (f1) and the structural unit derived from acrylic acid or methacrylic acid and the structural unit (a1). Here, as said structural unit (a1) copolymerized with the structural unit (f1), the structural unit derived from 1-ethyl-1-cyclooctyl (meth) acrylate, 1-methyl-1-adamantyl (meth) The structural unit derived from acrylate is preferred.

[Formula 85]

[Wherein, R is as defined above, 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 are the same It may be different. nf ¹ is an integer from 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 α 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 for 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 for Rf ¹⁰² and Rf ^{103 include} the same as the alkyl group having 1 to 5 carbon atoms for R, and a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ include a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. Especially, as Rf ¹⁰² and Rf ¹⁰³ , a hydrogen atom, a fluorine atom, or a C1-C5 alkyl group is preferable, and a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group is preferable.

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

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

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

Moreover, as for the hydrocarbon group containing a fluorine atom, it is preferable that 25% or more of the hydrogen atom in the said hydrocarbon group is fluorinated, it is more preferable that 50% or more is fluorinated, and that 60% or more is fluorinated, It is particularly preferable from the viewpoint of increasing the hydrophobicity of the resist film during immersion exposure.

Among them, Rf ¹⁰¹ is more preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, 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 are particularly preferred.

The mass average molecular weight (Mw) of the component (F) (based on polystyrene conversion by gel permeation chromatography) is preferably 1000 to 50000, more preferably 5000 to 40000, and most preferably 10000 to 30000. If it is less than or equal to the upper limit in this range, sufficient solubility in the solvent for resist is used for use as a resist, and if it is greater than or equal to the lower limit in this range, the water repellency of the resist film is good.

The dispersity (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.

In the resist composition of this embodiment, (F) component may be used individually by 1 type and may use 2 or more types together.

When the resist composition contains the component (F), the content of the component (F) is usually used in a proportion of 0.5 to 10 parts by mass relative to 100 parts by mass of the component (A).

≪ (S) component: Organic solvent component≫

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

As the component (S), any component to be used may be used as long as it is capable of dissolving each component to be used, and any of those known as solvents for conventional chemically amplified resist compositions can be appropriately selected and used.

(S) As a component, For example, lactones, such as γ-butyrolactone; Ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; Polyhydric alcohols such as ethylene glycol, 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, monomethyl ether, monoethyl ether of the polyhydric alcohols or compounds having the ester bond, Derivatives of polyhydric alcohols such as monoalkyl ethers such as monopropyl ether and monobutyl ether or compounds having ether bonds such as monophenyl ether [among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) is preferable]; Cyclic ethers such as dioxane, esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate and ethyl ethoxypropionate; Anisole, ethylbenzyl ether, cresylmethyl ether, diphenyl ether, dibenzyl ether, phenitol, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cement, mesitylene And aromatic organic solvents such as dimethyl sulfoxide (DMSO).

In the resist composition of this embodiment, (S) component may be used individually by 1 type and may be used as 2 or more types of mixed solvents.

Among them, PGMEA, PGME, γ-butyrolactone, EL, and cyclohexanone are preferable.

Further, a mixed solvent in which PGMEA and a polar solvent are mixed is also preferable. The compounding ratio (mass ratio) may be appropriately determined in consideration of the compatibility of PGMEA and a 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 blending EL or cyclohexanone as a polar solvent, the mass ratio of PGMEA: EL or cyclohexanone is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8 : 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME is preferably 1: 9-9: 1, More preferably 2: 8-8: 2, More preferably 3: 7- It is 7: 3. Also, a mixed solvent of PGMEA, PGME and cyclohexanone is preferred.

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

The amount of the (S) component is not particularly limited, and is appropriately set according to the thickness of the coating film at a concentration applicable to a substrate or the like. In general, the (S) component is used so that the solid content concentration of the resist composition is in the range of 0.1 to 50% by mass, preferably 10 to 50% by mass.

In the resist composition of the present embodiment, additionally miscible additives, for example, additional resins for improving the performance of the resist film, dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like, are suitably used. , Can be added.

In the resist composition of the present embodiment, after dissolving the resist material in the component (S), impurities such as a polyimide porous film, a polyamideimide porous film, or the like may be removed. For example, the resist composition may be filtered using a filter made of a porous polyimide film, a filter made of a polyamide-imide porous film, a filter made of a polyimide porous film or a polyamide-imide porous film, or the like. Examples of the porous polyimide film and the porous polyamideimide film include, for example, those described in Japanese Unexamined Patent Publication No. 2016-155121.

The resist composition of this embodiment contains a base component (A) and a dissolution preventing agent (Z). The dissolution preventing agent (Z) contains the compound (Z1) and the compound (Z2).

In general, in the resist film formed using the resist composition, a space is formed between the molecules constituting the base component. When the molecular weight of the base component increases, the molecules constituting the base component also increase, so that the space between the molecules increases. The space formed in such a resist film may lower the adhesion of the resist film to the substrate.

In the resist composition of the present embodiment, both the compound (Z1) and the compound (Z2) have a mass average molecular weight of 3000 or less, so the molecular size is relatively small. Therefore, in the resist film formed using the resist composition of the present embodiment, the compound (Z1) and the compound (Z2) tend to be suitably dispersed in a space formed between molecules constituting the base component (A).

Since the compound (Z1) has a phenolic hydroxyl group or a carboxyl group in the molecule, it tends to segregate in the lower layer in the resist film. Therefore, it is presumed that the compound (Z1) contributes to improving the adhesion between the resist film and the substrate interface, and improves the etching resistance (especially wet etching resistance).

On the other hand, since the compound (Z1) has a phenolic hydroxyl group or a carboxyl group in the molecule, there is a concern that the film may be reduced in the resist film, especially in the alkali developing process. However, compound (Z2) has higher hydrophobicity than compound (Z1). Therefore, it is presumed that the compound (Z2) contributes to the suppression of the film reduction of the resist film which may be caused by the compound (Z1).

It is presumed that, by the synergistic effect of the compound (Z1) and the compound (Z2), a resist pattern having good etching resistance and a good shape is obtained.

(How to form a resist pattern)

The second aspect of the present invention includes a step (i) of forming a resist film on the support using the resist composition according to the first aspect described above, a step (ii) of exposing the resist film, and a resist film after the exposure. It is a resist pattern formation method which has the process (iii) of developing and forming a resist pattern.

As one embodiment of such a resist pattern forming method, for example, a resist pattern forming method performed in the following manner is exemplified.

Process (i):

First, on the support, the resist composition of the above-described embodiment is coated with a spinner or the like and subjected to a bake (post-applied bake (PAB)) treatment, for example, at a temperature condition of 80 to 160 ° C. for 40 to 200 seconds. , Preferably, it is carried out for 60 to 150 seconds to form a resist film.

Process (ii):

Next, the resist film is subjected to selective exposure by exposure or the like through a mask (mask pattern) on which a predetermined pattern is formed using, for example, an exposure apparatus such as a KrF exposure apparatus, and then bake (post exposure bake ( PEB)) treatment is carried out, for example, at a temperature condition of 80 to 150 ° C for 40 to 150 seconds, preferably 60 to 120 seconds.

Process (iii):

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

After the developing treatment, rinsing treatment is preferably performed. For the rinse treatment, in the case of the alkali developing process, a rinse using pure water is preferable, and in the case of the solvent developing process, it is preferable to use a rinse liquid containing an organic solvent.

In the case of the solvent developing process, after the developing treatment or the rinsing treatment, a treatment in which the developing solution or the rinsing liquid adhered to the pattern is removed with a supercritical fluid may be performed.

After developing treatment or rinsing treatment, drying is performed. Further, in some cases, a baking treatment (post-baking) may be performed after the developing treatment. The baking treatment (post-baking) is carried out for 10 to 120 seconds, preferably 300 to 90 seconds, for example, at a temperature condition of 80 ° C or higher, preferably 90 to 120 ° C.

In this way, a resist pattern can be formed.

It does not specifically limit as a support body, A conventionally well-known thing can be used, For example, the board | substrate for electronic components, the thing in which a predetermined wiring pattern was formed in this, etc. are mentioned. More specifically, a silicon wafer, a metal substrate such as copper, chromium, iron, or aluminum, a glass substrate, or the like can be cited. As the material of the wiring pattern, copper, aluminum, nickel, gold, and the like can be used, for example.

Moreover, as a support body, an inorganic type and / or organic type film may be formed on the substrate as mentioned above. An inorganic antireflection film (inorganic BARC) is mentioned as an inorganic film. Examples of the organic film include organic antireflection films (organic BARC) and organic films such as lower layer organic films in the multilayer resist method.

Here, with the multilayer resist method, at least one layer of an organic film (lower layer organic film) and at least one layer of a resist film (upper layer resist film) are formed on a substrate, and a resist pattern formed on the upper layer resist film is used as a mask. This is a method of patterning the lower organic film, and it is said that a pattern with a high aspect ratio can be formed. That is, according to the multilayer resist method, since the required thickness can be ensured by the lower layer organic film, the resist film can be thinned, and fine pattern formation with a high aspect ratio can be achieved.

As a multilayer resist method, basically, a method having a two-layer structure of an upper resist film and a lower organic film (two-layer resist method), and one or more intermediate layers (metal thin film, etc.) between the upper resist film and the lower organic film The method is divided into a method of forming a multilayer structure of three or more layers (three-layer resist method).

The method for forming a resist pattern in the embodiment is a method useful when forming a thick film resist film. Even if the thickness of the resist film formed in the step (i) is, for example, 1 to 10 μm, the resist pattern can be stably formed in a good shape.

The wavelength used for exposure is not particularly limited, and ultraviolet rays such as g-ray and i-ray, ArF excimer laser light, KrF excimer laser light, F ₂ excimer laser light, EUV (extreme ultraviolet light), VUV (vacuum ultraviolet light), EB (Electron beam), X-rays, soft X-rays or the like can be used.

The resist composition according to the first aspect described above has high usefulness for ultraviolet rays such as g-rays and i-rays, KrF excimer laser light, ArF excimer laser light, EB or EUV, and ultraviolet rays such as g-rays and i-rays, KrF It is more useful for excimer laser light and ArF excimer laser light, and particularly useful for ultraviolet rays such as g-ray and i-ray, and KrF excimer laser light. The method for forming a resist pattern according to the second aspect is a particularly preferable method in the step (ii), when the resist film is irradiated with ultraviolet rays such as g-rays or i-rays or KrF excimer laser light.

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

The immersion exposure is an exposure method in which the resist film and the lens at the lowest position of the exposure apparatus are previously filled with a solvent (immersion medium) having a refractive index greater than the refractive index of air, and exposure (immersion exposure) is performed in that state.

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

Examples of the solvent having a refractive index greater than the refractive index of air and smaller than the refractive index of the resist film include water, fluorine-based inert liquids, silicon-based solvents, and hydrocarbon-based solvents.

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 , and C ₅ H ₃ F ₇ as a main component. The boiling point is preferably 70 to 180 ° C, more preferably 80 to 160 ° C. If the fluorine-based inert liquid has a boiling point in the above range, it is preferable because the medium used for immersion can be removed by a simple method after the completion of exposure.

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

Further, specifically, as the perfluoroalkyl ether compound, perfluoro (2-butyl-tetrahydrofuran) (boiling point 102 deg. C) may be mentioned. As the perfluoroalkylamine compound, perfluoro Rotributylamine (boiling point 174 ° C).

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

As an alkali developing solution used for image development process in an alkali developing process, 0.1-10 mass% tetramethylammonium hydroxide (TMAH) aqueous solution is mentioned, for example.

As the organic solvent contained in the organic developing solution used for the developing treatment in the solvent developing process, the component (A) (the component (A) before exposure) may be used as long as it can dissolve, and can be appropriately selected from known organic solvents. Specifically, polar solvents, such as a ketone solvent, an ester solvent, an alcohol solvent, a nitrile solvent, an amide solvent, and an ether solvent, a hydrocarbon solvent, etc. are mentioned.

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 alcohol-based solvent is an organic solvent containing an alcoholic hydroxyl group in the structure. "Alcoholic hydroxyl group" means a hydroxyl group bonded to a carbon atom of an aliphatic hydrocarbon group. The nitrile-based solvent is an organic solvent containing a nitrile group in the structure. The amide-based solvent is an organic solvent containing an amide group in the structure. The ether-based solvent is an organic solvent containing C-O-C in the structure.

Among the organic solvents, there are also organic solvents containing a plurality of functional groups that characterize each of the solvents in the structure, but in that case, it is also applicable to any solvent species containing functional groups of the organic solvent. For example, diethylene glycol monomethyl ether shall be applicable to either the alcohol-based solvent or the ether-based solvent in the above classification.

The hydrocarbon-based solvent is a hydrocarbon solvent composed of hydrocarbons which may be halogenated and does not have a 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 developer, a polar solvent is preferable, and a ketone solvent, an ester solvent, a nitrile solvent, and the like are preferable.

As a ketone solvent, for example, 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl Ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, acetonyl acetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methylnaphthyl ketone, Isophorone, propylene carbonate, γ-butyrolactone, methyl amyl ketone (2-heptanone), and the like. Among these, methyl amyl ketone (2-heptanone) is preferable as the ketone solvent.

As the ester solvent, for example, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxy acetate, ethyl ethoxy acetate, 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 monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3 -Methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl Acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl Acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, Ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, 2 -Ethyl hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, and the like. . Among these, butyl acetate is preferable as the ester solvent.

Examples of the nitrile solvent include acetonitrile, propionyl 2 tolyl, valeronitrile, and butyro 2 tolyl.

Known additives can be added to the organic developer, if necessary. Examples of the additives include surfactants. Although it does not specifically limit as surfactant, For example, ionic or nonionic fluorine type and / or silicone type surfactant, etc. can be used. As the surfactant, a nonionic surfactant is preferable, and a nonionic fluorine-based surfactant or nonionic silicone-based surfactant is more preferable.

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

The developing treatment can be carried out by a known developing method, for example, a method of immersing a support in a developer for a certain time (dip method), a method of suspending a developer on the surface of the support by surface tension, and stopping for a certain time (puddle) Method), a method of spraying a developer on the surface of a support (spray method), a method of continuously drawing a developer while scanning a nozzle for drawing a developer at a constant speed on a support rotating at a constant speed (dynamic dispensing method), and the like. .

As the organic solvent contained in the rinse liquid used for the rinse treatment after the developing treatment in the solvent developing process, for example, among the organic solvents used as the organic solvent used for the organic developer, a resist pattern that is difficult to dissolve is suitably selected and used. Can be. Usually, at least one solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents is used. Among them, at least one selected from hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, alcohol-based solvents and amide-based solvents is preferable, and at least one selected from alcohol-based solvents and ester-based solvents is more preferable, and alcohol-based solvents are preferred. Solvents are particularly preferred.

The alcohol-based solvent used for the rinse liquid is preferably a monohydric alcohol having 6 to 8 carbon atoms, and the monohydric alcohol may be any of linear, branched or cyclic. Specifically, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4 -Octanol, benzyl alcohol, and the like. Among these, 1-hexanol, 2-heptanol, and 2-hexanol are preferable, and 1-hexanol and 2-hexanol are more preferable.

Any one of these organic solvents may be used alone, or two or more of them may be used in combination. Moreover, you may use it, mixing with the organic solvent other than the above and water. However, considering the development characteristics, the blending amount of water in the rinse liquid is preferably 30% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less, 3 Particularly preferred is mass% or less.

Known additives can be added to the rinse liquid as necessary. Examples of the additives include surfactants. As the surfactant, the same ones described above can be used, and nonionic surfactants are preferred, and nonionic fluorine-based surfactants or nonionic silicone-based surfactants are more preferred.

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

The rinse treatment (washing treatment) using a rinse liquid can be performed by a known rinse method. As a method of the rinsing treatment, for example, a method of continuously drawing a rinse liquid on a support that is rotating at a constant speed (rotation coating method), a method of immersing the support in a rinse liquid for a certain time (dip method), on the surface of the support The method of spraying a rinse liquid (spray method), etc. are mentioned.

In the resist pattern forming method of the present embodiment described above, since the resist composition according to the first aspect described above is used, it is presumed that a resist pattern having good etching resistance and a good shape is obtained.

Such a resist composition and a method for forming a resist pattern are useful, for example, in applications in which a thick resist film is required. In addition, such a resist composition and a method for forming a resist pattern are useful for the purpose of processing a multi-stage stepped structure, and by applying the present invention, it is possible to realize stacking of a memory film (three-dimensionalization, production of a large-capacity memory) with high precision. have.

Example

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

<Preparation of resist composition>

(Examples 1 to 10, Comparative Examples 1 to 3)

Each component shown in Table 1 was mixed and dissolved to prepare a resist composition (solid content concentration: 30% by mass) in each example.

In Table 1, each symbol has the following meaning. The value in [] is the blending amount (parts by mass).

(A) -1: A polymer compound represented by the following formula (A1-1). The mass average molecular weight (Mw) of standard polystyrene conversion calculated by GPC measurement was 10000, and the molecular weight dispersion degree (Mw / Mn) was 2.14. ^{13 The} composition ratio of the copolymer obtained by C-NMR (the ratio (molar ratio) of each structural unit in the structural formula) is l / m / n = 61/14/25.

[Formula 86]

(B1) -1: A compound represented by the following formula (B1-1).

[Formula 87]

(Z1) -1: A compound represented by the following formula (Z1-1). The mass average molecular weight (Mw) is 268.35.

(Z1) -2: A compound represented by the following formula (Z1-2). The mass average molecular weight (Mw) was 424.53.

(Z1) -3: A compound represented by the following formula (Z1-3). The mass average molecular weight (Mw) is 352.43.

(Z1) -4: A compound represented by the following formula (Z1-4). The mass average molecular weight (Mw) is 246.31.

(Z1) -5: A compound represented by the following formula (Z1-5). The mass average molecular weight (Mw) was 292.29.

[Formula 88]

(Z2) -1: A compound represented by the following formula (Z2-1). The mass average molecular weight (Mw) was 953.21.

(Z2) -2: A compound represented by the following formula (Z2-2). The mass average molecular weight (Mw) is 827.1.

[Formula 89]

(S) -1: Mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether (mass ratio 50/50).

<How to form a resist pattern>

Process (i):

On the silicon substrate subjected to the hexamethyldisilazane (HMDS) treatment, the resist compositions of each example were respectively applied using a spinner, and subjected to a prebaking (PAB) treatment at 90 ° C. for 120 seconds at 90 ° C., By drying, a resist film having a thickness of 5.0 µm was formed.

Process (ii):

Subsequently, a high-pressure mercury lamp (365 nm) was masked on the resist film by an i-line stepper (reduction projection exposure apparatus: NSR-2205i14E (manufactured by Nikon Corporation; NA (number of apertures) = 0.57, σ = 0.67)). It was selectively irradiated through a pattern (6% halftone).

Subsequently, a heating (PEB) treatment was performed after exposure at 110 ° C. for 60 seconds.

Process (iii):

Subsequently, as a developing solution, 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Oka Industries Co., Ltd.) was used, and alkali development was performed at 23 ° C for 60 seconds.

Thereafter, a baking treatment (post-baking) was performed at 100 ° C for 60 seconds.

As a result, isolated line patterns (hereinafter referred to as "IS patterns") having a space width of 3 µm and a pitch of 15 µm were formed.

<Evaluation of dry etching>

The IS pattern formed by the above-described method for forming a resist pattern was dry-etched under the following conditions using an etching apparatus manufactured by Tokyo Oka Industries.

Condition :

Type and flow rate of etching gas; Tetrafluoromethane 30 cc / min. And trifluoromethane 30 cc / min. And helium 100 cc / min. Mixed gas

pressure ; 300 mmTorr

Print ; 600 w

time ; 120 seconds

The cross-sectional shape of the IS pattern after dry etching was observed with a scanning electron microscope (Product name: S4500; manufactured by Hitachi, Ltd.) to evaluate the presence or absence of undercut (etching under the pattern). Table 2 shows the results.

<Evaluation of wet etching>

A part of the substrate on which the IS pattern was formed was cut out by the above-described method for forming a resist pattern, and immersed in 23% buffered hydrofluoric acid for 12 minutes.

The cross-sectional shape of the IS pattern after immersion was observed with a scanning electron microscope (product name: S4500; manufactured by Hitachi, Ltd.) to evaluate the side etching amount (µm). Table 2 shows the results.

(Evaluation of pattern film reduction)

The resist composition of each example was applied onto an 8-inch silicon wafer by using a spinner, and a pre-baking (PAB) treatment at 120 ° C for 90 seconds was performed on a hot plate, followed by drying to obtain a film thickness of 5.0 µm. A resist film was formed.

Subsequently, the resist film was alkali-developed by using a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution "NMD-3" (trade name, manufactured by Tokyo Oka Industries Co., Ltd.) as a developing solution at 23 ° C for 60 seconds. Was carried out.

Thereafter, whisk drying was performed by spin coating, and the film thickness (nm) of the resist film was measured by using Nanospec 6100A (manufactured by Nanometrics). Table 2 shows the results.

From the results shown in Table 2, when a resist pattern was formed using the resist compositions of Examples 1 to 10 to which the present invention was applied, the film reduction of the pattern was suppressed, and both dry etching resistance and wet etching resistance were good. Was confirmed.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. Addition, omission, substitution, and other changes to the configuration are possible without departing from the spirit of the present invention. The present invention is not limited by the above description, but only by the scope of the attached claims.

Claims (4)

As a resist composition which generates an acid by exposure and the solubility in a developer is changed by the action of an acid,
Substrate component (A) whose solubility in developer changes by the action of an acid, and
Solubility inhibitor (Z) that inhibits solubility in developer
Containing,
The dissolution inhibitor (Z),
Compound (Z1) having a mass average molecular weight of 3000 or less and having a phenolic hydroxyl group or a carboxyl group in the molecule,
Compound (Z2) having a mass average molecular weight of 3000 or less and represented by the following general formula (z2)
The resist composition comprising a.

[Wherein, R _z ²⁰ is an acid dissociative group. R _z ³⁰ is a hydrogen atom or an organic group. n1 is an integer of 1-6, n2 is an integer of 0-5. However, n1 + n2 = 6.] According to claim 1,
The resist composition whose content of the said dissolution preventive agent (Z) is 30 mass parts or less with respect to 100 mass parts of the said base material component (A). According to claim 1,
The compounding ratio (mass ratio) of the compound (Z1) and the compound (Z2) is
Z1: Z2 = 75:25 to 25:75 phosphorus, resist composition. A step of forming a resist film on the support using the resist composition according to any one of claims 1 to 3 (i), a step of exposing the resist film (ii), and developing the resist film after the exposure to resist A method of forming a resist pattern, which has a step (iii) of forming a pattern.