TWI548936B - Photoresist composition, photoresist pattern formation method - Google Patents

Description

Photoresist composition, method for forming photoresist pattern

The present invention relates to a photoresist composition and a method for forming a photoresist pattern using the photoresist composition.

a lithography technique, for example, forming a photoresist film formed of a photoresist material on a substrate, and selectively exposing the photoresist film to a mask of a specific pattern by using radiation such as light or electron lines And a method of developing treatment, and performing a step of forming a photoresist pattern of a specific shape on the photoresist film.

A photoresist material whose refractive portion is changed to have solubility characteristics to a developing solution is referred to as a positive type, and a photoresist material whose exposed portion is changed to have no solubility property to a developing solution is referred to as a negative type.

In recent years, in the manufacture of semiconductor elements or liquid crystal display elements, with the advancement of the lithography technique, the pattern has been rapidly refining.

The method of miniaturization is generally performed in such a manner that the exposure light source is shortened (high energy). Specifically, ultraviolet rays typified by g-line and i-line have been used in the past, but currently, mass production of semiconductor elements has been started using KrF excimer lasers or ArF excimer lasers. Further, studies have been started on electron beams, EUV (extreme ultraviolet rays) or X-rays which are shorter wavelengths (high energy) than these excimer lasers.

Among the photoresist materials, lithographic etching characteristics such as the sensitivity of the exposure light sources and the resolution of the pattern of the reproducible fine size are sought.

A photoresist material which satisfies these requirements is generally composed of a chemically amplified photoresist which contains a substrate component which changes the solubility of the developer by the action of an acid, and an acid generator component which generates an acid by exposure. Things.

For example, in the case where the developing solution is an alkali developing solution (alkali developing process), a positive type chemically amplified resist composition generally uses a resin component containing an increase in solubility to an alkali developing solution by an action of an acid ( Base resin), with the acid generator component. When the photoresist film formed by the photoresist composition is selectively exposed in the formation of a photoresist pattern, an acid generator component generates an acid in the exposed portion, and the resin component is increased by the action of the acid. The solubility of the large alkali developer is such that the exposed portion is soluble in the alkali developer. Further, the unexposed portion remains as a pattern to form a positive pattern. Among them, since the base resin can increase the polarity of the resin by the action of an acid, the solubility in the alkali developer is increased, and the solubility in the organic solvent is lowered. Therefore, not only the alkali developing process, but also the process of using a developing solution (organic developing solution) containing an organic solvent (hereinafter, also referred to as a solvent developing process or a negative developing process), the exposure portion is relatively lowered. In the solvent development process, the unexposed portion of the photoresist film is dissolved and removed by the organic developer, and the exposed portion remains in a pattern to form a negative photoresist pattern. . For example, in Patent Document 1, there is a process of proposing negative development.

At present, in the ArF excimer laser lithography etching, the base resin of the photoresist composition used has excellent transparency in the vicinity of 193 nm, and generally has a (meth) acrylate (meta) in the main chain. Acrylic acid ester) A resin (Acryl resin) of a structural unit derived therefrom (for example, refer to Patent Document 2).

In recent years, with the required high-resolution photoresist pattern of 0.15 μm or less, it is necessary to improve the scum (residue) generated after development in addition to the above-mentioned lithography etching characteristics. Urgency.

In recent years, in the production of semiconductor elements, liquid crystal display elements, MEMS (Micro Electro Mechanical Systems), etc., an impurity diffusion layer is often formed on the surface of a support. The formation of the impurity diffusion layer is usually carried out in two stages, such as introduction and diffusion of impurities, and one of the methods of introduction is, for example, ionization of impurities such as phosphorus or boron in a vacuum, and acceleration of ions entering the surface of the support at a high electric frequency. Implantation process.

A photoresist pattern formed on a support using a chemically amplified photoresist composition is widely used for masking when etching a support (substrate). Recently, a photoresist pattern is used for the above ion implantation. In the process, when the impurity ions are selectively implanted on the surface of the support, they are also used as a mask for the driving.

The composition used in the ion implantation process has revealed a (meth) acrylate resin containing an acid-dissociable group which is dissociated by an acid dissociable group, and an acid generator, and contains as an acid diffusion inhibiting agent. A composition of a radiation-sensitive linear resin (novolac resin) for ion ion implantation of an amine (Patent Document 3).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] JP-A-2009-025707

[Patent Document 2] JP-A-2003-241385

[Patent Document 3] JP-A-2010-276624

In the future, as the lithography process progresses and the photoresist pattern becomes more refined, in the photoresist material, improvement of various lithography etching characteristics or reduction of scum is expected.

Further, in the ion implantation application described above, in order to prevent the antireflection film from being blocked, the antireflection film cannot be formed on the support of the photoresist pattern. Since there is no anti-reflection film, when the conventional chemical amplification type photoresist composition is used for the ion implantation process, the adhesion of the photoresist composition to the support such as the substrate is insufficient, and the photoresist composition is caused. Easy to peel off and other issues. In particular, in the case of using a base resin having a structural unit derived from (meth) acrylate, since the base resin has low adhesion to the substrate, the base resin mainly uses an ArF excimer laser or the like as an exposure light source. The problem of lithography etching will be particularly significant. On the other hand, in the composition described in Patent Document 3, there is still room for improvement in terms of the lithographic etching characteristics.

The present invention has been made in view of the above circumstances, and provides a photoresist composition having excellent lithography etching properties and adhesion, reducing scum, and a method for forming a photoresist pattern using the photoresist composition. for purpose.

In order to solve the above problems, the present invention adopts the following constitution.

That is, the first aspect of the present invention is a photoresist composition characterized by comprising a substrate component (A) which changes the solubility of a developing solution by an action of an acid, and an acid which generates an acid by exposure. a polymer component (B), a polymer compound (C) having a structural unit (c0) represented by the following formula (c0), and a compound (D1) represented by the following formula (d1), a photoreactive inhibitor (D) of one or more selected from the group consisting of the compound (D2) represented by the formula (d2) and the compound (D3) represented by the following formula (d3), Wherein R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; and R ¹ is an alcoholic hydroxyl group having one or more of the first or second order, or a chain of three Alkyl alcoholic organic group].

Wherein R ³ is a hydrocarbon group which may have a substituent, and Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (however, S is a carbon atom which is not substituted by a fluorine atom), and R ⁴ is The organic group, Y ³ is a linear, branched or cyclic alkyl or aryl group, Rf ₀ is a hydrocarbon group, and Z ⁺ is a separate ruthenium or osmium cation.

A second aspect of the present invention is a method for forming a photoresist pattern, comprising the step of forming a photoresist film on a support using the photoresist composition of the first aspect, and forming the photoresist film a step of exposing, and a step of developing the photoresist film to form a photoresist pattern.

In the present specification and the scope of the present patent application, "aliphatic" is a relative concept of aromatics, and is defined as a substance having no aromatic group or a compound.

The "alkyl group" is a linear monovalent, branched or cyclic monovalent saturated hydrocarbon group unless otherwise specified. The alkyl group in the alkoxy group is also the same.

The "alkylene group" is a linear, branched, and cyclic divalent saturated hydrocarbon group unless otherwise specified.

The "halogenated alkyl group" is a group in which a part or all of a hydrogen atom of an alkyl group is substituted by a halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like.

"Fluorinated alkyl group" or "fluorinated alkyl group" means a group in which a part or all of a hydrogen atom of an alkyl group or an alkyl group is substituted by a fluorine atom.

The "structural unit" has the meaning of a monomer unit constituting a polymer compound (resin, polymer, copolymer).

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

The "structural unit derived from acrylate" is intended to have a structural unit composed of cleavage of an ethylenic double bond of acrylate.

In the present specification, acrylic acid or acrylate which is substituted by a substituent with a hydrogen atom bonded to a carbon atom at the α-position is also referred to as an α-substituted acrylic acid or an α-substituted acrylate, respectively. Further, it includes acrylic acid and α-substituted acrylic acid, which is also referred to as "(α-substituted) acrylic acid, and includes acrylic acid and α-substituted acrylate, also referred to as "(α-substituted) acrylate".

The substituent in which the carbon atom at the α-position of the α-substituted acrylic acid or its ester is bonded, for example, a halogen atom, an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, or a hydroxyalkyl group. Further, the α-position (the carbon atom at the α-position) of the structural unit derived from the acrylate is not particularly limited, and means the carbon atom to which the carbonyl group is bonded.

The halogen atom as a substituent of the above-mentioned α-position is, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like.

The alkyl group having 1 to 5 carbon atoms as the substituent of the above α position, specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, A linear or branched alkyl group such as a pentyl group, an isopentyl group or a neopentyl group.

The halogenated alkyl group having 1 to 5 carbon atoms as the substituent of the α-position, specifically, for example, a part or all of the hydrogen atom in the above-mentioned alkyl group having 1 to 5 carbon atoms is substituted by a halogen atom. Base. The halogen atom is, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, and particularly preferably a fluorine atom.

The hydroxyalkyl group as the substituent of the above α position is preferably a hydroxyalkyl group having 1 to 5 carbon atoms, specifically, for example, a part of a hydrogen atom in the above alkyl group having 1 to 5 carbon atoms or All of the groups substituted by a hydroxyl group and the like.

In the present invention, the carbon atom bonded to the α-position of (α-substituted) acrylic acid or an ester thereof is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms. A hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferred, and a hydrogen atom or a methyl group is preferred from the viewpoint of industrial easiness.

The "organic group" is a group containing a carbon atom, and may have an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (a fluorine atom, a chlorine atom, etc.)).

The organic group of the (α-substituted) acrylate is not particularly limited, and examples thereof include a functional group such as an aromatic group, a polar group, and an acid-decomposable group described later, and a characteristic group having a characteristic group in the structure. Base and so on.

"Exposure" is the concept of full illumination containing radiation.

According to the present invention, in order to provide a photoresist composition having excellent lithography etching characteristics and adhesion, reducing scum, and using the photoresist composition The formation method of the photoresist pattern.

[Embodiment of the Invention] ≪ photoresist composition ≫

The photoresist composition of the first aspect of the present invention contains a substrate component (A) (hereinafter also referred to as "(A) component)) which changes the solubility of the developer by the action of an acid. An acid generator component (B) (hereinafter, also referred to as "(B) component)), a polymer compound (C) (hereinafter also referred to as "(C) component)), and a photoreactive type Inhibitor (D) (hereinafter also referred to as "(D) ingredient").

When the photoresist film formed by the photoresist composition is used for selective exposure in the formation of a photoresist pattern, the component (B) generates an acid which changes the solubility of the component (A) to the developer. . As a result, the solubility of the developer in the exposed portion of the photoresist film is changed, and the unexposed portion is still not changed in the solubility of the developer. When the photoresist is developed, the photoresist is composed. When the object is positive, the exposed portion will be dissolved and removed to form a positive photoresist pattern. When the photoresist composition is negative, the unexposed portion will be dissolved and removed to form a negative light. Resistance pattern.

In the present specification, the exposed portion is dissolved and removed, and the photoresist composition forming the positive resist pattern is referred to as a positive resist composition, and the unexposed portion is dissolved and removed to form a negative resist pattern resist. The composition is referred to as a negative photoresist composition. The photoresist composition of the present invention may be a positive photoresist composition or a negative photoresist composition. Moreover, the photoresist composition of the present invention can be used as a development process using an alkali developer when used in the formation of a photoresist pattern. The alkali developing process may be used in a solvent developing process for developing a developing solution (organic developing solution) containing an organic solvent in the developing process. Preferably, in the alkali developing process, a user who forms a positive resist pattern is used. In this case, the component (A) is a component which increases the solubility to the alkali developing solution by the action of an acid.

<(A) ingredient>

(A) As the component, an organic compound which is a substrate component for a chemically amplified photoresist may be used alone or in combination of two or more.

Here, the "substrate component" means 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 formation energy can be improved, and a photoresist pattern of a nanometer level can be easily formed.

The "organic compound having a molecular weight of 500 or more" used as the substrate component can be roughly classified into a non-polymer and a polymer.

The non-polymer is usually one having a molecular weight of 500 or more and less than 4,000. Hereinafter, a non-polymer having a molecular weight of 500 or more and less than 4,000 is referred to as a low molecular compound.

The polymer is usually one having a molecular weight of 1,000 or more. Hereinafter, a polymer having a molecular weight of 1,000 or more is referred to as a polymer compound. In the case of a polymer compound, "molecular weight" is a mass average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography). Hereinafter, the polymer compound is also referred to simply as "resin."

The component (A) may be used as a resin component which changes the solubility of the developer by the action of an acid, or may be used as a low molecular compound component which changes the solubility of the developer by the action of an acid. .

The component (A) may be one in which the solubility in the developer is increased by the action of an acid, and the solubility in the developer may be lowered by the action of an acid.

In the alkali developing process of the photoresist composition of the present invention, in order to form a photoresist pattern of a negative pattern (or a positive photoresist pattern in a solvent developing process), the component (A) is used as a base. The developer has a solvent component (hereinafter, also referred to as (A0') component), and a crosslinking agent component is added. When the photoresist composition generates an acid from the component (B) by exposure, crosslinking between the (A0') component and the crosslinking component is caused by the action of the acid, and as a result, the alkali developer is lowered. Solubility (the organic developer will increase its solubility). Therefore, in the formation of the photoresist pattern, when the photoresist film obtained by applying the photoresist composition on the support is selectively exposed, the exposed portion is converted to a poorly soluble alkali developer (for the organic developer) At the same time, since the unexposed portion is still soluble in the alkali developing solution (which is insoluble to the organic developing solution) and does not change, the negative resist pattern can be formed when developing through the alkali developing solution. Moreover, when an organic developing solution is used as the developing solution at this time, a positive resist pattern can be formed.

As the component (A0'), a known resin which is known to be soluble in an alkali developer (hereinafter also referred to as "alkali-soluble resin") can be used.

An alkali-soluble resin, for example, disclosed in Japanese Laid-Open Patent Publication No. 2000-206694 a resin having a unit derived from at least one selected from the group consisting of α-(hydroxyalkyl)acrylic acid, or an alkyl ester of α-(hydroxyalkyl)acrylic acid (preferably an alkyl ester having 1 to 5 carbon atoms) An acrylic resin or a polycyclic olefin resin having a carbon atom at the alpha position of a sulfonamide group capable of bonding an atom or a substituent other than a hydrogen atom, as disclosed in U.S. Patent No. 6,943,325; U.S. Patent No. 6,499,325, JP-A-2005 An acrylic resin containing a fluorinated alcohol and a carbon atom at the alpha position to bond an atom or a substituent other than a hydrogen atom, as disclosed in Japanese Laid-Open Patent Publication No. Hei. No. 2006-317803. In general, a polycyclic olefin resin having a fluorinated alcohol or the like is preferable because it can form a good photoresist pattern having less swelling.

Further, the α-(hydroxyalkyl)acrylic acid is an acrylic acid in which an atom at the α-position is bonded to an atom or a substituent other than a hydrogen atom, and a carbon atom bonded to the α-position of the carboxyl group is bonded to a hydrogen atom. Acrylic acid, one or both of the α-hydroxyalkylacrylic acid having a hydroxyalkyl group (preferably a hydroxyalkyl group having 1 to 5 carbon atoms) bonded to the carbon atom at the α-position.

The crosslinking agent component is usually an amine crosslinking agent such as acetylene urea having a methylol group or an alkoxymethyl group, or a melamine crosslinking agent, etc., so that a good photoresist pattern with less swelling can be formed. Type, but preferred. The amount of the crosslinking agent component to be added is preferably from 1 to 50 parts by mass based on 100 parts by mass of the alkali-soluble resin.

The photoresist composition of the present invention is a case where a positive pattern is formed in an alkali developing process and a photoresist pattern of a negative pattern is formed in a solvent developing process, and the component (A) is preferably via an acid. Increase the polarity of the substrate component (A0) (hereinafter also referred to as "(A0) component"). (A0) The composition changes due to the polarity before and after exposure, so that not only the alkali development process, but also a good development contrast can be obtained in the solvent development process.

That is, in the case of the alkali developing process, the component (A0) is insoluble to the alkali developing solution before the exposure, and when the acid is generated from the component (B) by exposure, the polarity is increased by the action of the acid, and the polarity is increased. Solubility of large alkali developer. Therefore, in the formation of the photoresist pattern, when the photoresist film obtained by coating the photoresist composition on the support is selectively exposed, the exposed portion is insoluble in the alkali developer, and is not exposed. The part is still under the condition that the alkali is poorly soluble, and the positive pattern can be formed by alkali development.

On the other hand, in the case of a solvent developing process, the component (A0) is highly soluble in the organic developing solution before exposure, and when the acid is generated from the component (B) by exposure, the polarity is increased by the action of the acid. Reduce the solubility of organic developer. Therefore, in the formation of the photoresist pattern, when the photoresist film obtained by applying the photoresist composition on the support is selectively exposed, the exposed portion is soluble in the organic developer and is insoluble, and is not When the exposed portion is still soluble, when the organic developing solution is used for development, a contrast can be imparted between the exposed portion and the unexposed portion, and a negative pattern can be formed.

In the photoresist composition of the present invention, the component (A) is preferably (A0). That is, the photoresist composition of the present invention can form a positive type in the alkali developing process, and a negative-type chemically amplified resist composition can be formed in the solvent developing process.

The (A0) component may be a resin component (A1) (hereinafter, also referred to as "(A1) component)) which is increased in polarity by an action of an acid, or a low molecular compound which increases polarity by an action of an acid. The component (A2) (hereinafter also referred to as "(A2) component") may also be used, or the mixture may be used.

[(A1) ingredients]

In the component (A1), a resin component (base resin) used as a substrate component for a chemically amplified photoresist may be used alone or in combination of two or more.

In the present invention, the component (A1) is preferably a structural unit (a1) having an acid-decomposable group which increases polarity by an action of an acid.

(Structural unit (a1))

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

The "acid-decomposable group" means that when at least a part of the bond of the structure of the acid-decomposable group is cleaved by the action of an acid generated by the component (B) by exposure, the acid-decomposable property is obtained. The basis.

The acid-decomposable group which increases the polarity by the action of an acid, for example, is decomposed by the action of an acid to generate a group of a polar group or the like.

The polar group constituting the acid-decomposable group is, for example, a carboxyl group, a hydroxyl group, an amine group, a sulfo group (-SO ₃ H) or the like. Among these, a carboxyl group or a hydroxyl group is preferred, and a carboxyl group is particularly preferred.

An acid-decomposable group, more specifically, for example, the aforementioned polar group is dissociated by an acid A group protected by a group (for example, a group in which a hydrogen atom of the aforementioned polar group is protected by an acid dissociable group) or the like.

The "acid dissociable group" means that, when subjected to an acid generated by the component (B) by exposure, at least the bond between the acid dissociable group and the atom adjacent to the acid dissociable group is cracked. It has the basis of acid dissociation. The acid dissociable group constituting the acid-decomposable group must be a group having a polarity lower than that of the polar group formed by dissociation of the acid dissociable group, so that the acid dissociable group is dissociated by the action of an acid. Further, a polar group having a polarity higher than the acid dissociable group is generated, and the polarity of the (A) component is increased. When the polarity of the component (A) is increased, the alkali development process increases the solubility of the exposed portion to the alkali developer, and the solvent development process reduces the solubility of the exposed portion to the organic developer.

The acid-dissociable group is not particularly limited, and an acid-dissociable group which has been proposed as a base resin for chemically amplified photoresist has been used. In general, for example, a carboxyl group in a (meth)acrylic acid or the like is formed into a cyclic or chain-like tertiary alkyl ester group, or an acetal acid dissociable group such as an alkoxyalkyl group.

Here, the "trialkyl ester" means a hydrogen atom of a carboxyl group which is substituted with a chain or a cyclic alkyl group to form an ester, and a terminal oxycarbonyl group of the carbonyloxy group (-C(=O)-O-) On the atom, the structure obtained by bonding the tertiary carbon atoms of the aforementioned chain or cyclic alkyl group means. In the tertiary alkyl ester, when an acid acts, the bond between the oxygen atom and the tertiary carbon atom is cleaved to form a carboxyl group.

The aforementioned chain or cyclic alkyl group which may have a substituent.

Hereinafter, the acid dissociable group is formed via the constitution of a carboxyl group and a tertiary alkyl ester, and it is referred to as a "tri-alkyl ester type acid dissociable group" for convenience.

The tertiary alkyl ester type acid dissociable group, for example, contains an aliphatic branched acid dissociable group, an acid dissociable group of an aliphatic cyclic group, and the like.

Here, the "aliphatic branched shape" means a group having a branched structure without aromaticity. The structure of the "aliphatic branched acid dissociable group" is not particularly limited as long as it is a group (hydrocarbon group) formed of carbon and hydrogen, and a hydrocarbon group is preferred. Further, the "hydrocarbon group" may be either saturated or unsaturated, and it is usually preferred to saturate.

An aliphatic branched acid dissociable group, for example, a group represented by -C(R ⁷¹ )(R ⁷² )(R ⁷³ ). In the formula, R ⁷¹ to R ⁷³ are each independently a linear alkyl group having 1 to 5 carbon atoms. a group represented by -C(R ⁷¹ )(R ⁷² )(R ⁷³ ), preferably having a carbon number of 4 to 8, specifically, for example, tert-butyl, 2-methyl-2-butyl, 2 -Methyl-2-pentyl, 3-methyl-3-pentyl and the like. Especially tert-butyl is preferred.

In the aliphatic branched acid dissociable group, a part of a hydrogen atom may be substituted by a fluorine atom. In this case, one of R ⁷¹ , R ⁷² and R ⁷³ represented by the above-mentioned -C(R ⁷¹ )(R ⁷² )(R ⁷³ ) is a fluorinated alkyl group, and two of them are an alkyl group. good. The fluorinated alkyl group is preferably a group represented by -(CH ₂ ) _w20 -CF ₃ . W20 is an integer from 0 to 3.

The "aliphatic cyclic group" means a monocyclic group or a polycyclic group which does not have an aromatic group.

The aliphatic cyclic group in the "acid-dissociable group containing an aliphatic cyclic group" may have a substituent or may have no substituent. Substituents, for example, An alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms, and an oxygen atom (=O).

The basic ring structure of the substituent of the aliphatic cyclic group is not particularly limited as long as it is a group (hydrocarbon group) formed of carbon and hydrogen, and a hydrocarbon group is preferred. Further, the hydrocarbon group may be either saturated or unsaturated, and it is usually preferred to saturate.

The aliphatic cyclic group may be a single ring type or a multi ring type.

The aliphatic cyclic group has a carbon number of 3 to 30, preferably 5 to 30, more preferably 5 to 20, and 6 to 15 is preferred, and 6 to 12 is the best. The monocyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from a monocyclic alkane. The monocyclic alkane is preferably a carbon number of 3 to 6, and specifically, for example, cyclobutane, cyclopentane, cyclohexane or the like. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from a polycyclic alkane, and the polycyclic alkane is preferably a carbon number of 7 to 12, specifically, for example, Adamantane, norbornane, isodecane, tricyclodecane, tetracyclododecane, and the like. Further, one of the carbon atoms constituting the ring of the aliphatic cyclic group may be substituted by an ether group (-O-).

An acid-dissociable group containing an aliphatic cyclic group, for example, an atom adjacent to the acid-dissociable group on the ring skeleton of the monovalent aliphatic ring group (for example, -C(=O)-O -中中-O-) a carbon atom-bonded substituent (atom or group other than a hydrogen atom) to form a group of a tertiary carbon atom; (ii) a monovalent aliphatic ring group; a group of a branched alkyl group having a tertiary carbon atom bonded thereto.

In the group (i) above, a substituent bonded to a carbon atom of an atom adjacent to the acid dissociable group, for example, an alkyl group or the like, is bonded to the ring skeleton of the aliphatic ring group. The alkyl group is, for example, the same as R ¹⁴ in the following formulae (1-1) to (1-9).

Specific examples of the group of the above (i) are, for example, groups represented by the following general formulae (1-1) to (1-9).

Specific examples of the group (ii) include, for example, a group represented by the following general formulae (2-1) to (2-6).

[wherein, R ¹⁴ is an alkyl group, and g is an integer of 0 to 8].

[wherein, R ¹⁵ and R ¹⁶ are each independently an alkyl group].

In the formulae (1-1) to (1-9), the alkyl group of R ¹⁴ may be any of a linear chain, a branched chain, and a cyclic chain.

The linear alkyl group preferably has a carbon number of 1 to 5, preferably 1 to 4, more preferably 1 or 2. Specifically, for example, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group or the like. Among them, a methyl group, an ethyl group or an n-butyl group is preferred, and a methyl group or an ethyl group is more preferred.

The branched alkyl group preferably has a carbon number of 3 to 10 and preferably 3 to 5. Specifically, for example, isopropyl, isobutyl, tert-butyl, isopentyl, neopentyl or the like is preferably isopropyl.

The cyclic alkyl group preferably has a carbon number of 3 to 20, more preferably 4 to 12. Specifically, for example, one monocyclic alkane such as cyclopentane or cyclohexane or one polycyclic alkane such as adamantane, norbornane, isodecane, tricyclodecane or tetracyclododecane is removed. The base obtained by the above hydrogen atom and the like. A part of the carbon atom constituting the ring of the cyclic alkyl group may be substituted by an etheric oxygen atom (-O-).

It is preferable that g is an integer of 0 to 3, preferably an integer of 1 to 3, more preferably 1 or 2.

In the formulae (2-1) to (2-6), the alkyl group of R ¹⁵ to R ¹⁶ is the same as the alkyl group of the above R ¹⁴ .

In the above formulae (1-1) to (1-9) and (2-1) to (2-6), a part of the carbon atoms constituting the ring may be substituted by an etheric oxygen atom (-O-).

Further, in the formulae (1-1) to (1-9) and (2-1) to (2-6), a hydrogen atom bonded to a carbon atom constituting the ring may be substituted with a substituent. The substituent is, for example, an alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated alkyl group or the like.

"acetal type acid dissociable group", in general, is a substituted carboxyl group or a hydroxyl group. The base or the like contains a hydrogen atom at the terminal of the polar group of OH and is bonded to the oxygen atom. Subsequently, when an acid is generated by exposure, the acetal-type acid dissociable group and the bond between the oxygen atom bonded to the acetal-type acid dissociable group are cleaved by the action of the acid to form a bond. A carboxyl group, a hydroxyl group or the like contains a polar group of OH.

The acetal type acid dissociable group is, for example, a group represented by the following formula (p1).

Wherein R ^{1 '} and R ^{2 '} each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n represents an integer of 0 to 3, and Y represents an alkyl group having 1 to 5 carbon atoms or an aliphatic cyclic group. ].

In the formula (p1), n is preferably an integer of 0 to 2, preferably 0 or 1, and most preferably 0.

The alkyl group of R ^{1 '} and R ^{2 '} , for example, in the description of the above-mentioned α-substituted acrylate, the alkyl group exemplified as the substituent at the α-position is the same, and the methyl group or the ethyl group is preferably a methyl group. For the best.

In the present invention, it is preferred that at least one of R ^{1 '} and R ^2' is a hydrogen atom. That is, the acid-dissociable group (p1) is preferably a group represented by the following formula (p1-1).

[wherein, R ^{1 '} , n, and Y are the same as described above].

The alkyl group of Y is, for example, the same as the alkyl group as the substituent of the α-position described above.

The aliphatic ring group of Y may be appropriately selected from among the monocyclic or polycyclic aliphatic ring groups which have been proposed by conventional ArF photoresists, for example, and the above-mentioned "containing aliphatic ring group" The aliphatic cyclic group exemplified as the acid dissociable group is the same content and the like.

The acetal type acid dissociable group is, for example, a group represented by the following formula (p2).

[wherein, R ¹⁷ and R ¹⁸ are each independently a linear or branched alkyl group or a hydrogen atom; and R ¹⁹ is a linear, branched or cyclic alkyl group. Or, R ¹⁷ and R ¹⁹ are each independently a linear or branched alkyl group, and R ¹⁷ and R ¹⁹ may be bonded to form a ring].

In R ¹⁷ and R ¹⁸ , the carbon number of the alkyl group is preferably from 1 to 15, which may be either a linear chain or a branched chain, and is preferably an ethyl group or a methyl group, and a methyl group is the most good.

In particular, one of R ¹⁷ and R ¹⁸ is a hydrogen atom, and the other is preferably a methyl group.

R ¹⁹ is a linear, branched or cyclic alkyl group, and the carbon number is preferably from 1 to 15, and may be any of a linear chain, a branched chain or a cyclic chain.

When R ¹⁹ is a linear or branched form, it is preferably a carbon number of 1 to 5, more preferably an ethyl group or a methyl group, and most preferably an ethyl group.

When R ¹⁹ is a ring, it is preferably 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, for example, one polycyclic alkane such as a monocyclic alkane, a bicycloalkane, a tricycloalkane or a tetracycloalkane which may be substituted by a fluorine atom or a fluorinated alkyl group or unsubstituted is removed. The base or the like obtained by the above hydrogen atom is, for example, the same as the above-mentioned "aliphatic cyclic group". Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferred.

Further, in the above formula (p2), R ¹⁷ and R ¹⁹ are each independently a linear or branched alkyl group (preferably an alkyl group having 1 to 5 carbon atoms), and further, R ¹⁹ and R. ¹⁷ can form a bond.

In this case, R ¹⁷ , an oxygen atom bonded to R ¹⁹ and R ¹⁹ , and a carbon atom bonded to the oxygen atom and R ¹⁷ may form a ring group. The ring base is preferably a 4 to 7 ring, and a 4 to 6 ring is preferred. Specific examples of the cyclic group, tetrahydropyranyl group, tetrahydrofuranyl group and the like.

The structural unit (a1) is not particularly limited as long as it is a unit having an acid-decomposable group, and an acrylate in which a hydrogen atom bonded to a carbon atom of the α-position can be substituted with a substituent is used. The structural unit derived, and the structural unit containing the acid-decomposable group (a11), the hydrogen atom bonded to the carbon atom at the α-position may be substituted by a substituent, and the hydrogen atom bonded by the benzene ring may be substituted by a hydroxyl group. The structural unit (a12) in which the hydrogen atom in the hydroxyl group of the structural unit derived from the hydroxystyrene substituted by the group is substituted by the substituent containing the acid dissociable group or the acid dissociable group, and the carbon atom in the α position are bonded thereto. The hydrogen atom may be substituted by a substituent, and the hydrogen atom to which the naphthalene ring is bonded may be A structural unit (a13) obtained by substituting a hydrogen atom in a hydroxyl group of a structural unit derived from a vinyl group (hydroxynaphthalene) substituted with a substituent other than a hydroxyl group with an acid dissociable group or a substituent containing an acid dissociable group. From the viewpoint of line edge roughness, the structural unit (a11) is preferable, and EUV or EB is used as the exposure light source in the lithography etching, and the EUV wavelength or the EB wavelength is easily absorbed, in the structural unit (a12)~(a13) ) is better.

{Structural unit (a11)}

In the structural unit (a11), a hydrogen atom to which a carbon atom of the α-position is bonded may be a structural unit derived from an acrylate substituted with a substituent, and a structural unit containing an acid-decomposable group.

The structural unit (a11) is, for example, a structural unit represented by the following general formula (a1-0-1), a structural unit represented by the following general formula (a1-0-2), and the like.

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; X ¹ is an acid dissociable group; Y ² is a divalent bond group; and X ² is an acid Dissociative base].

In the formula (a1-0-1), the alkyl group of R, the alkyl group of the halogenated group, respectively In the description of the α-substituted acrylate, the alkyl group or the halogenated alkyl group exemplified as the substituent at the α-position is the same. R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, and preferably a hydrogen atom or a methyl group.

X ¹ is not particularly limited as long as it is an acid dissociable group, and for example, the above-mentioned tertiary alkyl ester type acid dissociable group, acetal type acid dissociable group, etc., and dissociated by a tertiary alkyl ester type acid The sex base is better.

In the formula (a1-0-2), R is the same as described above.

X ² is the same as X ¹ in the formula (a1-0-1).

The bonding group of the two-valent Y ² is not particularly limited, and examples thereof include a divalent hydrocarbon group which may have a substituent, a divalent bond group containing a hetero atom, and the like.

(a divalent hydrocarbon group which may have a substituent)

The hydrocarbon group which is a divalent bond group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

The aliphatic hydrocarbon group is intended to mean a hydrocarbon group which does not have aromaticity. The aliphatic hydrocarbon group may be either saturated or unsaturated, and is usually saturated.

More specifically, the aliphatic hydrocarbon group is, for example, a linear or branched aliphatic hydrocarbon group or a hydrocarbon group having a ring in the structure.

The linear or branched aliphatic hydrocarbon group preferably has a carbon number of 1 to 10, preferably 1 to 8, more preferably 1 to 5.

a linear aliphatic hydrocarbon group, preferably a linear alkyl group, specifically, for example, a methyl group [-CH ₂ -], an extended ethyl group [-(CH ₂ ) ₂ -], a trimethyl group [-(CH ₂ ) ₃ -], tetramethyl [-(CH ₂ ) ₄ -], pentamethyl [-(CH ₂ ) ₅ -], and the like.

a branched aliphatic hydrocarbon group, preferably a branched alkyl group, specifically, for example, -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ - , -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and the like alkyl-methyl; -CH ( CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -C(CH ₂ CH _{3 2} -CH ₂ -isoalkyl extended ethyl; -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ -, etc. alkyl-extended trimethyl; -CH(CH ₃ )CH ₂ An alkyl group such as CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH ₂ - or the like extends to an alkyl group such as a tetramethyl group. The alkyl group in the alkylalkyl group is preferably a linear alkyl group having 1 to 5 carbon atoms.

The linear or branched aliphatic hydrocarbon group may have a substituent (a group other than a hydrogen atom or an atom) which substitutes a hydrogen atom, and may or may not be. The substituent is, for example, a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted by a fluorine atom, a ketone group (=O) or the like.

The aliphatic hydrocarbon group having a ring in the above structure, for example, a cyclic aliphatic hydrocarbon group which may have a substituent containing a hetero atom in the ring structure (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring), the aforementioned cyclic aliphatic group The hydrocarbon group is bonded to the terminal group of the linear or branched aliphatic hydrocarbon group, and the cyclic aliphatic hydrocarbon group is in the middle of the linear or branched aliphatic hydrocarbon group. The linear or branched aliphatic hydrocarbon group is, for example, the same as described above.

The cyclic aliphatic hydrocarbon group preferably has a carbon number of 3 to 20 and preferably 3 to 12.

The cyclic aliphatic hydrocarbon group may be a polycyclic ring or a monocyclic ring. The monocyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocyclic alkane. The monocyclic alkane is preferably a carbon number of 3 to 6, and specifically, for example, cyclopentane or cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycyclic alkane, and the polycyclic alkane is preferably a carbon number of 7 to 12, specifically, for example, adamantane or a descending Decane, isodecane, tricyclodecane, tetracyclododecane, and the like.

The cyclic aliphatic hydrocarbon group may have a substituent (a group other than a hydrogen atom or an atom) which substitutes a hydrogen atom, or may have no. The substituent is, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a ketone group (=O) or the like.

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

The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert group. - Butoxy is preferred, and methoxy and ethoxy are preferred.

The halogen atom as the substituent, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

The halogenated alkyl group as the substituent is, for example, a group in which a part or all of the hydrogen atom of the alkyl group is substituted by the halogen atom.

In the cyclic aliphatic hydrocarbon group, a part of the carbon atom constituting the ring structure may be substituted by a substituent containing a hetero atom. The hetero atom-containing substituent is preferably -O-, -C(=O)-O-, -S-, -S(=O) ₂ -, -S(=O) ₂ -O-.

The aromatic hydrocarbon group as the divalent hydrocarbon group has at least one aromatic ring A divalent hydrocarbon group which may have a substituent. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be either a monocyclic ring or a polycyclic ring. The carbon number of the aromatic ring is preferably 5 to 30, preferably 5 to 20, more preferably 6 to 15, and particularly preferably 6 to 12. However, among the carbon numbers, those having no carbon number in the substituent are included. The aromatic ring is, for example, an aromatic hydrocarbon ring such as benzene, naphthalene, anthracene or phenanthrene; an aromatic heterocyclic ring which is a part of a carbon atom constituting the aromatic hydrocarbon ring and is substituted with a hetero atom; The hetero atom in the aromatic hetero ring is, for example, an oxygen atom, a sulfur atom, a nitrogen atom or the like. The aromatic heterocyclic ring is specifically, for example, a pyridine ring, a thiophene ring or the like.

Specific examples of the aromatic hydrocarbon group of the divalent hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or the aromatic heterocyclic ring (such as an aryl group or a heteroaryl group); An aromatic compound (for example, biphenyl, anthracene, etc.) of an aromatic ring obtained by removing two hydrogen atoms; and an aryl or heteroaryl group obtained by removing one hydrogen atom from the above aromatic hydrocarbon ring or aromatic heterocyclic ring a group in which one hydrogen atom is substituted by an alkyl group (for example, benzyl, phenylethyl, 1-naphthylmethyl, 2-naphthylmethyl, 1-naphthylethyl, 2-naphthalene) A group obtained by removing one hydrogen atom from an aryl group in an aralkyl group such as a ethyl group; The carbon number of the alkyl group bonded to the aryl group or the heteroaryl group is preferably from 1 to 4, more preferably from 1 to 2, particularly preferably from 1 to 1.

The aromatic hydrocarbon group may have a substituent or may have no substituent. For example, a hydrogen atom bonded to an aromatic ring of the aromatic group may be substituted with a substituent. The substituent is, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a ketone group (=O) or the like.

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

The alkoxy group as a substituent is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert group. - Butoxy is preferred, and methoxy and ethoxy are preferred.

The halogen atom as the substituent, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

The halogenated alkyl group as the substituent is, for example, a group in which a part or all of the hydrogen atom of the alkyl group is substituted by the halogen atom.

(containing a divalent bond of a divalent atom)

The hetero atom in the divalent bond group containing a hetero atom means an atom other than a carbon atom and a hydrogen atom, for example, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom or the like.

a divalent bond group containing a hetero atom, specifically, for example, -O-, -C(=O)-, -C(=O)-O-, -OC(=O)-O-, -S -, -S(=O) ₂ -, -S(=O) ₂ -O-, -NH-, -NH-C(=O)-, -NH-C(=NH)-, =N-, etc. A non-hydrocarbon-based bonding group, a combination of at least one of these non-hydrocarbon-based bonding groups, and a divalent hydrocarbon group. The divalent hydrocarbon group is, for example, the same as the above-mentioned divalent hydrocarbon group which may have a substituent, and is preferably a linear or branched aliphatic hydrocarbon group.

Among the above, H in -NH-, -NH-, -NH-C(=NH)- in -C(=O)-NH- may be substituted by a substituent such as an alkyl group or a fluorenyl group. The carbon number of the substituent is preferably from 1 to 10, more preferably from 1 to 8 carbon atoms, and from 1 to 5 carbon atoms. It is especially good.

Y ^{2 is} particularly preferably a linear or branched alkyl group, a divalent alicyclic hydrocarbon group, or a divalent bond group containing a hetero atom.

Y ² is a linear or branched alkyl group. The alkyl group is preferably a carbon number of 1 to 10, preferably a carbon number of 1 to 6, and a carbon number of 1 to 4. The carbon number of 1 to 3 is the best. Specifically, for example, in the description of the two-valent bond group in the above R ¹ , a linear alkyl group or a branched alkyl group as exemplified in the linear or branched aliphatic hydrocarbon group For the same content and so on.

In the case where Y ² is a divalent alicyclic hydrocarbon group, for example, in the description of the two-valent bond group in the above R ^0-1 , "the aliphatic hydrocarbon group having a ring in the structure" is listed. The alicyclic hydrocarbon group is the same content and the like.

The alicyclic hydrocarbon group is further obtained by removing two or more hydrogen atoms from cyclopentane, cyclohexane, norbornane, isodecane, adamantane, tricyclodecane or tetracyclododecane. good.

Y ² is a case of a divalent bond group containing a hetero atom, and a preferred one of the bond groups, for example, -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH- (H can be substituted by a substituent such as an alkyl group or a fluorenyl group), -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, general formula -Y ²¹ -OY ²² -, -[Y ²¹ -C(=O)-O] _m' -Y ²² - or -Y ²¹ -OC(= O)-Y ²² - a group represented by the formula [wherein Y ²¹ and Y ²² are each independently a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m' is an integer of 0 to 3].

In the case where Y ² is -NH-, the H may be substituted with a substituent such as an alkyl group or an aromatic group (for example, an aryl group). In the substituent (alkyl group, aromatic group, etc.), the number of carbon atoms is preferably from 1 to 10, more preferably from 1 to 8, and particularly preferably from 1 to 5.

Formula -Y ²¹ -OY ²² -, -[Y ²¹ -C(=O)-O] _m' -Y ²² - or -Y ²¹ -OC(=O)-Y ²² -, Y ²¹ and Y ²² are Each of them is independently a divalent hydrocarbon group which may have a substituent. The divalent hydrocarbon group is the same as those listed in the "divalent hydrocarbon group which may have a substituent" in the above Y ² .

Y ^{21 is} preferably a linear aliphatic hydrocarbon group, preferably a linear alkyl group, and preferably a linear alkyl group having 1 to 5 carbon atoms. Ethyl is especially good.

Y ^{22 is} preferably a linear or branched aliphatic hydrocarbon group, and more preferably a methyl group, an ethyl group or an alkyl group. The alkyl group in the methyl 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 base 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, with 0 or 1 as the Good, with 1 is especially good. That is, the group represented by the formula -[Y ²¹ -C(=O)-O] _m' -Y ²² - is particularly preferably a group represented by the formula -Y ²¹ -C(=O)-OY ²² -. Among them, the group represented by the formula -(CH ₂ ) _a' -C(=O)-O-(CH ₂ ) _b' - is preferred. In the formula, a' is an integer of 1 to 10, preferably an integer of 1 to 8, preferably an integer of 1 to 5, more preferably 1 or 2, and most preferably 1. b' is an integer from 1 to 10, preferably from 1 to 8 integers, preferably from 1 to 5, more preferably from 1 or 2, and most preferably from 1.

The divalent bond group containing a hetero atom in Y ² is preferably an organic group formed by combining at least one non-hydrocarbon group and a divalent hydrocarbon group. Further, it is preferably a linear group having an oxygen atom as a hetero atom, for example, a group having an ether bond or an ester bond, and the above formula -Y ²¹ -OY ²² -, -[Y ²¹ -C (=O)-O] _m' -Y ²² - or -Y ²¹ -OC(=O)-Y ²² - is preferably a group represented by the above formula - [Y ²¹ -C(=O)-O The base represented by _m' -Y ²² - or -Y ²¹ -OC(=O)-Y ²² - is preferred.

Y ² , in the above, further a linear or branched alkyl group, or a divalent bond group containing a hetero atom, preferably a linear or branched alkyl group, the foregoing a group represented by the formula -Y ²¹ -OY ²² -, a group represented by the above formula -[Y ²¹ -C(=O)-O] _m' -Y ²² - or the above formula -Y ²¹ -OC(=O )-Y ²² - The base represented is better.

The structural unit (a11) is more specifically, for example, a structural unit represented by the following general formulae (a1-1) to (a1-4).

[wherein, R, R ^{1 '} , R ^{2 '} , n, Y and Y ² are each the same as defined above, and X' represents a tertiary alkyl ester type acid dissociable group]. In the formula, X' is the same as the above-mentioned tertiary alkyl ester type acid dissociable group.

^{R 1 ', R 2',} n, Y, respectively, with the above-described "acetal-type acid dissociable group" as exemplified in the description of general formula (p1) in the ^{R 1 ', R 2',} n, Y is the same The content and so on.

Y ² is the same as Y ² in the above formula (a1-0-2).

The following is a specific example of the structural unit represented by the above general formulae (a1-1) to (a1-4).

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

In the present invention, the structural unit (a11) has a structural unit represented by the following general formula (a1-0-11), a structural unit represented by the following general formula (a1-0-12), and the following It is preferred that at least one selected from the group consisting of the structural unit represented by the formula (a1-0-13) and the structural unit represented by the following formula (a1-0-2). In addition, it is represented by the structural unit represented by the formula (a1-0-11), the structural unit represented by the following general formula (a1-0-12), and the following general formula (a1-0-2). It is preferred that at least one of the selected groups of structural units is selected.

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; R ²¹ is an alkyl group; and R ²² is a carbon atom bonded to the R ²² to form a fat a group of a monocyclic group, R ²³ is a branched alkyl group, and R ²⁴ is a group having an aliphatic polycyclic group together with the carbon atom bonded to the R ²⁴ , and R ²⁵ is a carbon number of 1 to 5. a linear alkyl group. Y ² is a divalent bond group, and X ² is an acid dissociable group].

In the respective formulas, the descriptions of R, Y ² and X ² are the same as those described above.

In the formula (a1-0-11), the alkyl group of R ²¹ is the same as the alkyl group of R ^{14 in} the above formulae (1-1) to (1-9), and is a methyl group or an ethyl group. The isopropyl group or a group obtained by removing one or more hydrogen atoms from a norbornane which may have a substituent is preferred.

R ²² , an aliphatic monocyclic group formed by the carbon atom bonded to the R ²² , for example, in the aliphatic cyclic group exemplified in the above-mentioned tertiary alkyl ester type acid dissociable group, as a monocyclic ring The basis of the base is the same content and the like. Specifically, for example, a group obtained by removing one or more hydrogen atoms from a monocyclic alkane or the like. The monocyclic alkane is preferably a 3 to 11 member ring, preferably a 3 to 8 member ring, preferably a 4 to 6 member ring, and a 5 or 6 member ring.

In the monocyclic alkane, a part of the carbon atoms constituting the ring may be substituted by an ether group (-O-) or may be unsubstituted.

Further, in the monocyclic alkane, the substituent may have an alkyl group having 1 to 5 carbon atoms, a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms.

R ²² constituting an aliphatic monocyclic group, for example, a linear alkyl group having an ether group (-O-) interposed between carbon atoms.

Specific examples of the structural unit represented by the formula (a1-0-11), for example, the above formulas (a1-1-16) to (a1-1-23), (a1-1-27), (a1-1-) 31), the structural unit represented by (a1-1-37), and the like. Among these, it includes equations (a1-1-16)~(a1-1-17), (a1-1-20)~(a1-1-23), (a1-1-27), ( The structural unit represented by the following (a1-1-02) of the structural unit represented by a1-1-31) and (a1-1-37) is preferable. Further, the structural unit represented by the following (a1-1-02') is also preferable.

In each formula, h is preferably 1 or 2.

[wherein R and R ²¹ are the same as described above, and h is an integer of 1 to 4].

In the formula (a1-0-12), a branched alkyl group of R ²³ and a branched alkyl group exemplified by the alkyl group of R ^{14 in} the above formula (1-1) to (1-9) For the same content, etc., isopropyl is the best.

R ^24, an aliphatic polycyclic group formed jointly with the carbon atom which R ²⁴ is bonded, the aforementioned three alkyl ester-type acid solution of the aliphatic cyclic group enumerated dissociable group, as the polycyclic group of The base is the same content and so on.

Specific examples of the structural unit represented by the formula (a1-0-12) include, for example, structural units represented by the above formulas (a1-1-26), (a1-1-28) to (a1-1-30), and the like. .

In the structural unit represented by the formula (a1-0-12), it is preferred that R ²⁴ and the aliphatic polycyclic group formed by the carbon atom bonded to the R ²⁴ are 2-adamantyl groups, particularly The structural unit represented by the above formula (a1-1-26) is preferred.

In the formula (a1-0-13), R and R ²⁴ are the same as those described above.

The linear alkyl group of R ²⁵ is the same as the linear alkyl group exemplified for the alkyl group of R ^{14 in} the above formulae (1-1) to (1-9), and is a methyl group or an ethyl group. For the best.

The structural unit represented by the formula (a1-0-13), specifically, for example, the formula (a1-1-1) to (a1-1-3) exemplified in the specific example of the above formula (a1-1) , the structural unit represented by (a1-1-7)~(a1-1-15), and the like.

In the structural unit represented by the formula (a1-0-13), it is preferred that R ²⁴ and the aliphatic polycyclic group formed by the carbon atom bonded to the R ²⁴ are 2-adamantyl groups, particularly The structural unit represented by the above formula (a1-1-1) or (a1-1-2) is preferred.

The structural unit represented by the formula (a1-0-2), for example, the structural unit represented by the above formula (a1-3) or (a1-4), particularly preferably the structural unit represented by the formula (a1-3) .

The structural unit represented by the formula (a1-0-2), in particular, Y ² in the formula is a group represented by the above formula -Y ²¹ -OY ²² -, the above formula - [Y ²¹ -C(=O)- The base represented by O] _{m' -} Y ²² - or the base represented by the above formula -Y ²¹ -OC(=O)-Y ²² - is preferred.

In the structural unit, for example, a structural unit represented by the following general formula (a1-3-01); a structural unit represented by the following general formula (a1-3-02); and the following general formula (a1- 3-03) The structural unit represented by etc.

[wherein R is the same as the above, R ¹³ is a hydrogen atom or a methyl group, R ¹⁴ is an alkyl group, y is an integer of 1 to 10, and n' is an integer of 0 to 3].

[wherein, R is the same as the above, and Y ^{2 '} and Y ^2" are each a two-valent bond group independently, and X' is an acid dissociable group, and w is an integer of 0 to 3].

In the formulae (a1-3-01) to (a1-3-02), R ¹³ is preferably a hydrogen atom.

R ¹⁴ is the same as R ¹⁴ in the above formulae (1-1) to (1-9).

Y is preferably an integer from 1 to 8, preferably from 1 to 5, and preferably 1 or 2.

n' is preferably 1 or 2, and 2 is most preferred.

Specific examples of the structural unit represented by the formula (a1-3-01) are, for example, structural units represented by the above formulas (a1-3-25) to (a1-3-26).

Specific examples of the structural unit represented by the formula (a1-3-02) are, for example, structural units represented by the above formulas (a1-3-27) to (a1-3-28).

In the formula (a1-3-03), the divalent bond group in Y ^{2 '} and Y ^{2 '} is, for example, the same as Y ² in the above formula (a1-0-2).

Y ^{2 ' is} preferably a divalent hydrocarbon group which may have a substituent, and a linear aliphatic hydrocarbon group is preferred, and a linear alkyl group is more preferred. Among them, a linear alkyl group having a carbon number of 1 to 5 is preferred, and a methyl group and an ethyl group are preferred.

Y ^{2" is} preferably a divalent hydrocarbon group which may have a substituent, preferably a linear aliphatic hydrocarbon group, more preferably a linear alkyl group, and a carbon number of 1 to 5. The chain-like alkyl group is preferred, and the methyl group and the ethyl group are most preferred.

The acid dissociable group in X' is the same as the above, and is preferably a tertiary alkyl ester type acid dissociable group, and the acid is on the ring skeleton of the above (i) monovalent aliphatic ring group. A group of a tertiary carbon atom formed by a carbon atom-bonded substituent bonded to an atom adjacent to the dissociable group is preferred, and a group represented by the above formula (1-1) is preferred.

w is an integer of 0~3, w, preferably an integer of 0~2, preferably 0 or 1, and 1 is the best.

The structural unit represented by the formula (a1-3-03) is preferably a structural unit represented by the following general formula (a1-3-03-1) or (a1-3-03-2), wherein The structural unit represented by a1-3-03-1) is preferred.

[wherein R and R ¹⁴ are respectively the same as described above, a' is an integer of 1 to 10, b' is an integer of 1 to 10, and t is an integer of 0 to 3].

In the formula (a1-3-03-1)~(a1-3-03-2), a' is preferably an integer from 1 to 8, preferably an integer from 1 to 5, preferably 1 or 2. good.

b' is preferably an integer of 1 to 8, preferably an integer of 1 to 5, and particularly preferably 1 or 2.

It is preferable that t is an integer of 1 to 3, and 1 or 2 is particularly preferable.

Specific examples of the structural unit represented by the formula (a1-3-03-1) or (a1-3-03-2), for example, represented by the above formulas (a1-3-29) to (a1-3-32) The structural unit and so on.

{Structural unit (a12)}

The structural unit (a12) is a structural unit in which a hydrogen atom bonded to a carbon atom in the alpha position can be substituted by a substituent, and a hydrogen atom bonded to the benzene ring can be replaced by a hydroxystyrene substituted with a substituent other than a hydroxyl group. A structural unit obtained by substituting a hydrogen atom in a hydroxyl group with an acid dissociable group or a substituent containing an acid dissociable group.

"Hydroxystyrene" is a compound obtained by bonding a vinyl group to at least one hydroxyl group. The number of hydroxyl groups bonded to the benzene ring is preferably from 1 to 3, with 1 being particularly preferred. The bonding position of the hydroxyl group in the benzene ring is not particularly limited. In the case where the number of hydroxyl groups is one, it is preferable that the bonding position of the vinyl group is four. In the case where the number of hydroxyl groups is an integer of 2 or more, it may be a combination of any bonding positions.

An acid-dissociable group of a substituted hydrogen atom in a hydroxyl group, for example, the same as described above, a tertiary alkyl ester type acid dissociable group or an acetal type acid dissociable group Preferably, the acetal acid dissociable group is more preferred.

The substituent containing an acid dissociable group is, for example, a group composed of an acid dissociable group and a divalent bond group. The divalent bond group is, for example, the same as the two-valent bond group in Y ² in the above formula (a1-0-2), and particularly the terminal structure of the acid dissociable base side is carbonyl. The base of the oxy group is preferred. In this case, it is preferred that the acid-dissociable group is bonded to the oxygen atom (-O-) of the carbonyloxy group.

The substituent having an acid-cleavable group is preferably a group represented by R ^{11 '} -OC(=O)- or a group represented by R ^{11 '} -OC(=O)-R ^12' -. In the formula, R ^{11 '} is an acid-dissociable group, and R ^{12 '} is a linear or branched alkylene group.

The acid dissociable group in R ^{11 '} is preferably a tertiary alkyl ester type acid dissociable group or an acetal type acid dissociable group, and more preferably a tertiary alkyl ester type acid dissociable group. A preferred example of the tertiary alkyl ester type acid dissociable group is an aliphatic branched acid dissociable group represented by -C(R ⁷¹ )(R ⁷² )(R ⁷³ ), and the formula (1-1) ) The base represented by ~(1-9), the base represented by the formula (2-1) to (2-6), and the like.

The alkyl group in R ^{12 '} , for example, a methyl group, an ethyl group, a trimethyl group, a tetramethyl group, a 1,1-dimethylmethyl group, and the like. R ^{12 ' is} preferably a linear alkyl group.

{Structural unit (a13)}

The structural unit (a13) is a vinyl group (hydroxynaphthalene) in which a hydrogen atom to which a carbon atom of the α-position is bonded may be substituted by a substituent, and a hydrogen atom to which a naphthalene ring is bonded may be substituted with a substituent other than a hydroxyl group ( Following, (α substituted) B The structural unit in which a hydrogen atom in a hydroxyl group of a structural unit derived from an alkenyl group (hydroxynaphthalene) is substituted with a substituent containing an acid dissociable group or an acid dissociable group.

"Vinyl (hydroxynaphthalene)" is a compound in which a naphthalene ring is bonded to one vinyl group and at least one hydroxyl group. The vinyl group may be bonded to the 1 position of the naphthalene ring or may be bonded to the 2 position. The number of hydroxyl groups bonded to the naphthalene ring is preferably from 1 to 3, and particularly preferably from 1. The bonding position of the hydroxyl group in the naphthalene ring is not particularly limited. In the case where the vinyl group is bonded to the 1 or 2 position of the naphthalene ring, it is preferred to bond to any of the 5 to 8 positions of the naphthalene ring. In particular, in the case where the number of hydroxyl groups is one, it is preferred to bond to any of the 5 to 7 positions of the naphthalene ring, and it is preferably 5 or 6 positions. In the case where the number of hydroxyl groups is an integer of 2 or more, it may be a combination of any bonding positions.

In the structural unit (a13), the acid-dissociable group of the substituted hydrogen atom in the hydroxyl group and the substituent containing the acid-dissociable group are, for example, the same as those described in the description of the structural unit (a12).

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

In the component (A1), the ratio of the structural unit (a1) is preferably 15 to 70 mol%, more preferably 15 to 60 mol%, and 20 to 20% of the total structural unit constituting the component (A1). 55% of the moles is better. When it is more than the lower limit value, when it is a photoresist composition, the pattern can be easily obtained, and the lithographic etching characteristics such as sensitivity, resolution, and pattern shape can be improved. Moreover, when it is less than the upper limit, the balance with other structural units can be acquired.

(Structural unit (a2))

The component (A1) may have, in addition to the structural unit (a1), a structural unit (a2) containing a ring group containing -SO ₂ - or a ring group containing a lactone.

The structural unit (a2) contains a ring group of a -SO ₂ - or a lactone ring group, and in the case where the component (A1) is used as a photoresist film, the adhesion between the photoresist film and the substrate is improved. The view is valid. In addition, it is effective in an alkali development process from the viewpoint of improving the affinity with a developer containing water such as an alkali developer.

Further, the structural unit (a1) has a ring-form group containing -SO ₂ - or a ring-form group containing a lactone in the structure, and the structural unit corresponds to the structural unit (a2), but in this case, These structural units are considered to correspond to the structural unit (a1) and not to the structural unit (a2).

Here, the "cyclic group containing -SO ₂ -" means that the ring skeleton contains a ring group containing a ring of -SO ₂ -, specifically, a sulfur atom in -SO ₂ - (S) A ring group formed as a part of a ring skeleton of a ring group. Counting the ring containing -SO ₂ - in the ring skeleton as a ring of one unit, and only the case of the ring is called a monocyclic group, and other ring structures are used, regardless of the structure. It is called a polycyclic group. The ring group containing -SO ₂ - may be a single ring type or a multiple ring type.

Containing -SO ₂ - of cyclic groups, especially the cyclic skeleton containing -O-SO ₂ - group of cyclic, i.e., containing -O-SO ₂ - in the -OS- to form a skeleton of the ring The ring group of the sultone ring is preferred.

The ring group containing -SO ₂ - has a carbon number of 3 to 30, preferably 4 to 20, more preferably 4 to 15, and 4 to 12 is particularly preferred. However, the carbon number is the number of carbon atoms constituting the ring skeleton, and is the number of carbon atoms in the substituent.

Containing -SO ₂ - group of cyclic, may contain -SO ₂ - of the aliphatic cyclic group may contain -SO ₂ - group of the aromatic ring also. It is preferably an aliphatic cyclic group containing -SO ₂ -.

An aliphatic cyclic group containing -SO ₂ -, for example, at least one hydrogen is removed from an aliphatic hydrocarbon ring in which one of the carbon atoms constituting the ring skeleton is substituted by -SO ₂ - or -O-SO ₂ - The basis of the atom, etc. More specifically, for example, a group obtained by removing at least one hydrogen atom from an aliphatic hydrocarbon ring in which -CH ₂ - which is a ring skeleton is substituted by -SO ₂ - is formed, and -CH ₂ -CH ₂ - which constitutes a ring thereof A group obtained by removing at least one hydrogen atom from an aliphatic hydrocarbon ring substituted by -O-SO ₂ -.

The alicyclic hydrocarbon ring preferably has a carbon number of 3 to 20, more preferably 3 to 12.

The alicyclic hydrocarbon ring may be a multi-ring type or a single-ring type. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocyclic alkane having 3 to 6 carbon atoms, and examples of the monocyclic alkane such as cyclopentane and cyclohexane are exemplified. The polycyclic alicyclic hydrocarbon ring is preferably a group obtained by removing two hydrogen atoms from a cycloalkane having 7 to 12 carbon atoms, specifically, for example, adamantane or rhodium. Alkane, isodecane, tricyclodecane, tetracyclododecane, and the like.

The cyclic group containing -SO ₂ - may have a substituent. The substituent is, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O), -COOR", -OC(=O)R", a hydroxyalkyl group, a cyano group or the like.

The alkyl group as the substituent is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a hexyl group and the like. Among them, a methyl group or an ethyl group is preferred, and a methyl group is particularly preferred.

The alkoxy group as the substituent is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specifically, for example, the group obtained by the alkyl group-bonded oxygen atom (-O-) exemplified as the alkyl group as the substituent is used.

As the halogen atom of the substituent, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like is preferably a fluorine atom.

The halogenated alkyl group of the substituent is, for example, a group in which a part or all of a hydrogen atom of the alkyl group is substituted by the aforementioned halogen atom.

The halogenated alkyl group as the substituent is, for example, a group in which a part or all of hydrogen atoms in the alkyl group exemplified as the alkyl group as the substituent is substituted by the halogen atom. The halogenated alkyl group is preferably a fluorinated alkyl group, particularly preferably a perfluoroalkyl group.

Any of R-" in the above -COOR" and -OC(=O)R" is a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms.

When R" is a linear or branched alkyl group, the carbon number is preferably from 1 to 10, more preferably from 1 to 5 carbon atoms, and particularly preferably methyl or ethyl.

When R" is a cyclic alkyl group, the carbon number is preferably from 3 to 15, and the carbon number is preferably from 4 to 12, and the carbon number is preferably from 5 to 10. Specifically, for example, it may be fluorine. a single-ring chain substituted with an atom or a fluorinated alkyl group, or unsubstituted A group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as a dicycloalkane, a tricycloalkane or a tetracycloalkane is exemplified. More specifically, for example, a monocyclic alkane such as cyclopentane or cyclohexane, or a polycyclic alkane such as adamantane, norbornane, isodecane, tricyclodecane or tetracyclododecane is removed. The base obtained by more than one hydrogen atom, and the like.

The hydroxyalkyl group as the substituent is preferably a carbon number of 1 to 6. Specifically, for example, at least one hydrogen atom of the alkyl group exemplified by the alkyl group as the substituent is substituted by a hydroxyl group. Base.

The ring group containing -SO ₂ -, more specifically, for example, a group represented by the following general formulae (3-1) to (3-4).

[wherein A' is an alkylene group, an oxygen atom or a sulfur atom having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, z is an integer of 0 to 2, and R ²⁷ is an alkyl group, an alkoxy group, or a halogenated group. Alkyl, hydroxy, -COOR", -OC(=O)R", hydroxyalkyl or cyano, R" is a hydrogen atom or an alkyl group].

In the above formula (3-1) to (3-4), A' is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom (-O-) or a sulfur atom (-S-), or an oxygen atom or Sulfur atom.

The alkyl group having 1 to 5 carbon atoms in A' is preferably a linear or branched alkyl group, and is a methyl group, an ethyl group, an n-propyl group, an iso-propyl group or the like.

The alkylene group contains an oxygen atom or a sulfur atom, and specifically, for example, a terminal derived from the alkyl group or a group in which a carbon atom is interposed with -O- or -S-, for example, -O-CH ₂ -, -CH ₂ -O-CH ₂ -, -S-CH ₂ -, -CH ₂ -S-CH ₂ -, and the like.

A' is preferably an alkylene group having a carbon number of 1 to 5 or -O-, and preferably an alkylene group having 1 to 5 carbon atoms, and preferably a methyl group.

z can be any of 0~2, and 0 is the best.

In the case where z is 2, the plural R ²⁷ may be the same or different.

In R ²⁷ the alkyl, alkoxy, halogenated alkyl group, -COOR ", - OC (= O) R", a hydroxyl group, respectively, and the -SO ₂ - group containing the cyclic group may have the substituent The alkyl group, alkoxy group, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group are the same contents.

The following are specific examples of the ring group represented by the above formulas (3-1) to (3-4). Further, "Ac" in the formula represents an ethyl group.

The cyclic group containing -SO ₂ -, in the above, is preferably a group represented by the above formula (3-1), and is used by the above chemical formula (3-1-1), (3-1) At least one selected from the group consisting of -18), (3-3-1) and (3-4-1) is preferably selected from the above chemical formula (3-1-1) The basis indicated is the best.

The "per lactone-containing cyclic group" means a cyclic group containing a ring containing -O-C(=O)- (lactone) in the ring skeleton. When the lactone ring is counted as the first ring, the case where only the lactone ring is called a monocyclic group, and the case of other ring structures, regardless of the structure, is called a polycyclic group. The cyclic group containing a lactone may be a monocyclic group or a polycyclic group.

The lactone ring group in the structural unit (a2) is not particularly limited, and any content can be used. Specifically, the monocyclic group containing a lactone is a group obtained by removing one hydrogen atom from 4 to 6 membered ring lactones, for example, a group obtained by removing one hydrogen atom from β-propiolactone, and γ. a group obtained by removing one hydrogen atom from butyrolactone, a group obtained by removing one hydrogen atom from δ-valerolactone, and the like. Further, the polycyclic group having a lactone is, for example, a group obtained by removing one hydrogen atom from a bicycloalkane having a lactone ring, a tricycloalkane or a tetracycloalkane.

The structural unit (a2), as long as it has a ring group containing -SO ₂ - or a ring group containing a lactone, the structure of the other part is not particularly limited, and the carbon atom of the alpha position The bonded hydrogen atom may be a structural unit derived from an acrylate substituted with a substituent, and has a structural unit (a2 ^S ) containing a ring group of -SO ₂ -, and a carbon atom bonded at the α position The hydrogen atom may be a structural unit derived from an acrylate substituted with a substituent, and at least one structural unit selected from the group consisting of a structural unit (a2 ^L ) containing a lactone-containing cyclic group is preferred.

‧Structural unit (a2 ^S ):

An example of the structural unit (a2 ^S ) is more specifically, for example, a structural unit represented by the following general formula (a2-0).

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; R ²⁸ is a cyclic group containing -SO ₂ -, and R ²⁹ is a single bond or a divalent group. Bond base].

In the formula (a2-0), R is the same as the above.

R ²⁸ is the same as the above-mentioned ring-form group containing -SO ₂ -.

R ²⁹ may be either a single bond or a divalent bond group. In view of making the effect of the present invention more excellent, a divalent bond group is preferred.

The divalent bond group in R ²⁹ is not particularly limited, and for example, it is the same as the bond group of the two valences in Y ² in the above formula (a1-0-2). Among them, those having an alkyl group or an ester bond (-C(=O)-O-) are preferred.

The alkyl group is preferably a linear or branched alkyl group. Specifically, for example, the linear alkyl group and the branched alkyl group which are exemplified in the aliphatic hydrocarbon group in the above Y ² are the same.

a divalent bond group containing an ester bond, particularly preferably a group represented by the formula: -R ³⁰ -C(=O)-O-[wherein R ³⁰ is a divalent bond group] . That is, the structural unit (a2 ^S ) is preferably a structural unit represented by the following general formula (a2-0-1).

[wherein R and R ²⁸ are each the same as described above, and R ³⁰ is a divalent bond group].

R ^{30 is} not particularly limited, and for example, it is the same as the two-valent bond group in Y ² in the above formula (a1-0-2).

a two-valent bond group of R ³⁰ , preferably a linear or branched alkyl group, an aliphatic hydrocarbon group having a ring in the structure, or a divalent bond group containing a hetero atom, preferably in a linear form It is preferably a branched alkyl group or a divalent bond group containing an oxygen atom as a hetero atom.

a linear alkyl group, preferably methyl or ethyl, to methyl It is especially good.

a branched alkyl group, preferably an alkyl methyl group or an alkyl group ethyl group, with -CH(CH ₃ )-, -C(CH ₃ ) ₂ - or -C(CH ₃ ) ₂ CH ₂ - Very good.

The divalent bond group containing an oxygen atom is preferably a divalent bond group containing an ether bond or an ester bond, and the above -Y ²¹ -OY ²² -, -[Y ²¹ -C(=O) -O] _m' -Y ²² - or -Y ²¹ -OC(=O)-Y ²² - is more preferred. Y ²¹ , Y ²² , and m' are the same as those described above.

The structural unit (a2 ^S ) is particularly preferably a structural unit represented by the following formula (a2-0-11) or (a2-0-12), and a structural unit represented by the formula (a2-0-12) For better.

[wherein, R, A', R ²⁷ , z and R ³⁰ are respectively the same as described above].

In the formula (a2-0-11), A' is preferably a methyl group, an oxygen atom (-O-) or a sulfur atom (-S-).

R ^{30 is} preferably a linear or branched alkyl group or a divalent bond group containing an oxygen atom. a linear or branched alkyl group in R ³⁰ and a divalent linking group containing an oxygen atom, respectively, and a linear or branched alkyl group as described above, containing an oxygen atom The bond base of the price is the same content and the like.

The structural unit represented by the formula (a2-0-12) is particularly preferably a structural unit represented by the following formula (a2-0-12a) or (a2-0-12b).

[wherein, R and A' are the same as described above, and c~e are independent integers of 1 to 3 respectively].

‧Structural unit (a2 ^L ):

In the example of the structural unit (a2 ^L ), for example, R ²⁸ in the above formula (a2-0) is exemplified by a lactone-containing cyclic group, and the like, more specifically, for example, the following formula (a2- 1) The structural unit represented by ~(a2-5).

Wherein R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; and R' is a hydrogen atom independently selected from the group consisting of an alkyl group, an alkoxy group, an alkyl halide group, and a hydroxyl group. -COOR", -OC(=O)R", hydroxyalkyl or cyano, R" is a hydrogen atom or an alkyl group; R ²⁹ is a single bond or a divalent bond group, and s" is an integer from 0 to 2 ; A" is an alkyl, oxygen or sulfur atom having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom; m is 0 or 1].

R in the general formulae (a2-1) to (a2-5) is the same as described above.

An alkyl group, an alkoxy group, an alkyl halide group, a -COOR", -OC(=O)R", a hydroxyalkyl group in R', and a substituent which may be present in the above-mentioned ring-form group containing -SO ₂ - The alkyl group, the alkoxy group, the alkyl halide group, the -COOR", the -OC(=O)R", and the hydroxyalkyl group are the same contents. R" is also the same as the foregoing.

R' is preferably a hydrogen atom when it is considered to be industrially easy to obtain.

A" is, for example, the same as A' in the above formula (3-1). A", an alkyl group having 1 to 5 carbon atoms, an oxygen atom (-O-) or a sulfur atom (-S) -) is preferable, and an alkyl group or -O- having a carbon number of 1 to 5 is more preferable. The alkyl group having 1 to 5 carbon atoms is preferably a methyl group or a dimethyl group, and the methyl group is most preferred.

R ²⁹ is the same as R ²⁹ in the above formula (a2-0).

In the formula (a2-1), s" is preferably 1 or 2.

The following is a specific example of the structural unit represented by the above formulas (a2-1) to (a2-5). In the following formulae, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit (a2 ^L ) is preferably at least one selected from the group consisting of the structural units represented by the above formulas (a2-1) to (a2-5), and is represented by the general formula (a2-1) At least one selected from the group consisting of structural units represented by ~(a2-3) is preferably a group formed by the structural unit represented by the above formula (a2-1) or (a2-3) At least one of the selected ones is particularly good.

Among them, by the above formula (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-7), (a2-2-12), (a2- It is preferable that at least one selected from the group consisting of structural units represented by 2-14) and (a2-3-1) and (a2-3-5) is preferable.

Further, the structural unit (a2 ^L ) is preferably a structural unit represented by the following formulas (a2-6) to (a2-7).

[wherein, R and R ²⁹ are the same as those described above].

(A1) The structural unit (a2) of the component may be one type or two or more types. For example, the structural unit (a2) may be used only in the structural unit (a2 ^S ), or only in the structural unit (a2 ^L ), or may be used in combination. Further, the structural unit (a2 ^S ) or the structural unit (a2 ^L ) may be used singly or in combination of two or more.

(A1) The composition has the structural unit (a2), and the ratio of the structural unit (a2) is preferably 1 to 80 mol%, and 10 to 70 mol, based on the total of the structural units constituting the (A1) component. The ear % is preferably, preferably from 10 to 65 mol %, and particularly preferably from 10 to 60 mol %. When it is more than the lower limit value, when the structural unit (a2) is contained, a sufficient effect can be obtained. When the value is less than the limit, a balance with other structural units can be obtained, and various fine lithographic etching characteristics and pattern shapes such as DOF and CDU can be obtained.

(Structural unit (a3))

The component (A1) may have a structural unit (a3) containing a polar group in addition to the structural unit (a1) or the structural units (a1) and (a2). When the component (A1) has a structural unit (a3), the polarity of the (A1) component after exposure can be increased upward. In the case of an increase in polarity, particularly in the case of an alkali developing process, the ability to improve the resolution can be imparted.

The polar group is, for example, -OH, -COOH, -CN, -SO ₂ NH ₂ , -CONH ₂ or the like. A group comprising -COOH, which also comprises a structural unit of (alpha substituted) acrylic acid.

The structural unit (a3) preferably has a structural unit of a hydrocarbon group in which a part of a hydrogen atom is substituted by a polar group. The hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Among them, the hydrocarbon group is more preferably an aliphatic hydrocarbon group.

An aliphatic hydrocarbon group in the hydrocarbon group, for example, a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group), or an aliphatic cyclic group (monocyclic group or polycyclic group) Wait.

The aliphatic cyclic group (monocyclic group or polycyclic group) can be suitably selected from most of the proposed components, for example, a resin which can be used for a resist composition for an ArF excimer laser. The carbon number of the aliphatic ring group is preferably from 3 to 30, preferably from 5 to 30, more preferably from 5 to 20, most preferably from 6 to 15, and most preferably from 6 to 12. Specifically, for example, removed by a monocyclic alkane A group obtained by two or more hydrogen atoms; a group obtained by removing two or more hydrogen atoms from a polycyclic alkane such as a bicycloalkane, a tricycloalkane or a tetracycloalkane. More specifically, for example, a group obtained by removing two or more hydrogen atoms from a monocyclic alkane such as cyclopentane or cyclohexane; from adamantane, norbornane, isodecane, tricyclodecane, tetracyclic A group obtained by removing two or more hydrogen atoms from a polycyclic alkane such as dodecane. The aliphatic cyclic group may have a substituent or may have no substituent. The substituent is, for example, an alkyl group having 1 to 5 carbon atoms, a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms.

The aromatic hydrocarbon group in the 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 4n+2 π electrons, and may be either a monocyclic ring or a polycyclic ring. The carbon number of the aromatic ring is preferably 5 to 30, preferably 5 to 20, more preferably 6 to 15, and particularly preferably 6 to 12. However, among the carbon numbers, those having no carbon number in the substituent are included. The aromatic ring is, for example, an aromatic hydrocarbon ring such as benzene, naphthalene, anthracene or phenanthrene; an aromatic heterocyclic ring which is a part of a carbon atom constituting the aromatic hydrocarbon ring and is substituted with a hetero atom; The hetero atom in the aromatic hetero ring is, for example, an oxygen atom, a sulfur atom, a nitrogen atom or the like. The aromatic heterocyclic ring is specifically, for example, a pyridine ring, a thiophene ring or the like.

Specific examples of the aromatic hydrocarbon group of the divalent hydrocarbon group include a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring or the aromatic heterocyclic ring (such as an aryl group or a heteroaryl group); and two or more aromatic rings. a group obtained by removing two hydrogen atoms from an aromatic compound (for example, biphenyl group, hydrazine, etc.); a group in which one hydrogen atom in the above aromatic ring is substituted by an alkyl group (for example, benzyl group, phenylethyl group) , 1-naphthylmethyl, 2-naphthylmethyl, 1- a group obtained by removing one hydrogen atom from an aromatic ring in an aralkyl group or a heteroarylalkyl group such as a naphthylethyl group or a 2-naphthylethyl group; The carbon number of the alkyl group of the substituted hydrogen atom of the aromatic hydrocarbon ring or the aromatic hetero ring is preferably from 1 to 4, more preferably from 1 to 2, particularly preferably from 1 to 1.

The aromatic hydrocarbon group may have a substituent. For example, a hydrogen atom bonded to an aromatic ring of the aromatic hydrocarbon group may be substituted by a substituent or the like. The substituent is, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O) or the like.

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

The halogen atom as the substituent of the aromatic hydrocarbon group, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

The halogenated alkyl group as the substituent is, for example, a group obtained by substituting a part or all of a hydrogen atom of the alkyl group with the halogen atom.

The structural unit (a3) is preferably a structural unit represented by the following general formula (a3-1).

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. L ⁰ is -C(=O)-O-, -C(=O)-NR ⁿ - (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or a single bond. R ⁰ is -COOH or has a group consisting of -OH, -COOH, -CN, -SO ₂ NH ₂ , -C(R ^r1 )(R ^r2 )(OH) and -CONH ₂ as substituents. The hydrocarbon group of at least one selected may have an oxygen atom or a sulfur atom at any position. R ^r1 and R ^r2 are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.

In the above formula (a3-1), the alkyl group of R is preferably a linear or branched alkyl group, specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group or an n-butyl group. Base, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, and the like.

The halogenated alkyl group of R, for example, a group obtained by substituting a part or all of a hydrogen atom in the alkyl group of R in the above with a halogen atom. The halogen atom is, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, and particularly preferably a fluorine atom.

R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms, particularly preferably a hydrogen atom or a methyl group.

In the above formula (a3-1), L ⁰ is -C(=O)-O-, -C(=O)-NR ⁿ - (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) or single bond. The alkyl group of R ⁿ is the same as the alkyl group of R.

In the above formula (a3-1), R ⁰ is, having -OH, -COOH, -CN, -SO ₂ NH ₂ , -C(R ^r1 )(R ^r2 )(OH) and -CONH as substituents The hydrocarbon group of at least one selected from the group of ₂ may have an oxygen atom or a sulfur atom at any position.

The "hydrocarbon group having a substituent" means that at least a part of a hydrogen atom bonded to a hydrocarbon group is substituted with a substituent.

The hydrocarbon group in R ⁰ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

The aliphatic hydrocarbon group in R ⁰ , a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkyl group), or an aliphatic cyclic group (monocyclic group or polycyclic group) For better illustration, the descriptions are the same as described above.

The aromatic hydrocarbon group in R ⁰ is a hydrocarbon group having an aromatic ring, and the description is the same as described above.

In the case of -C(R ^r1 )(R ^r2 )(OH) as a substituent in R ⁰ , R ^r1 and R ^r2 are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a carbon number of 1 to 5. Halogenated alkyl. The alkyl group having 1 to 5 carbon atoms and the halogenated alkyl group having 1 to 5 carbon atoms are the same as the alkyl group having 1 to 5 carbon atoms and the halogenated alkyl group having 1 to 5 carbon atoms as the substituent at the α position. .

However, R ⁰ may have an oxygen atom or a sulfur atom at any position. The "having an oxygen atom or a sulfur atom at any position thereof" means a hydrocarbon group or a part of a carbon atom (a carbon atom containing a substituent moiety) constituting a hydrocarbon group having a substituent, respectively, which can be oxygenated. The meaning of the substitution of an atom or a sulfur atom, or the hydrogen atom to which a hydrocarbon group is bonded, may be replaced by an oxygen atom or a sulfur atom.

The following exemplification is an illustration of R ⁰ which still has an oxygen atom (O) at an arbitrary position.

[wherein, W ⁰⁰ is a hydrocarbon group, and R ^m is an alkylene group having 1 to 5 carbon atoms].

In the above formula, W ⁰⁰ is a hydrocarbon group, and is, for example, the same as R ⁰ in the above formula (a3-1). W ^{00 is} preferably an aliphatic hydrocarbon group, more preferably an aliphatic cyclic group (monocyclic group or polycyclic group).

R ^{m is} preferably a linear chain or a branched chain, and preferably an alkylene group having 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group.

More suitable in the structural unit (a3), more specifically, for example, a structural unit derived from (α-substituted) acrylic acid, or any one of the following general formulae (a3-11) to (a3-13) The structural unit and so on.

The structural unit derived from (α-substituted) acrylic acid, for example, L ⁰ in the above formula (a3-1) is a single bond, and R ⁰ is a structural unit of -COOH.

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. W ⁰¹ is at least one selected from the group consisting of -OH, -COOH, -CN, -SO ₂ NH ₂ , -C(R ^r1 )(R ^r2 )(OH), and -CONH ₂ as substituents. An aromatic hydrocarbon group based on it. P ⁰² and P ⁰³ are each -C(=O)-O- or -C(=O)-NR ⁿ - (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). W ⁰² is at least one selected from the group consisting of -OH, -COOH, -CN, -SO ₂ NH ₂ , -C(R ^r1 )(R ^r2 )(OH) and -CONH ₂ as substituents. The cyclic hydrocarbon group may have an oxygen atom or a sulfur atom at any position. W ⁰³ is at least one selected from the group consisting of -OH, -COOH, -CN, -SO ₂ NH ₂ , -C(R ^r1 )(R ^r2 )(OH) and -CONH ₂ as substituents. a linear hydrocarbon group based on a base. R ^r1 and R ^r2 are the same as described above].

[Structural unit represented by the general formula (a3-11)]

In the above formula (a3-11), R is the same as the description of R in the above formula (a3-1).

The aromatic hydrocarbon group in W ⁰¹ is, for example, the same as the description of the aromatic hydrocarbon group in R ⁰ in the above formula (a3-1).

The following is a preferred specific example of the structural unit represented by the general formula (a3-11). In the following formulae, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[Structural unit represented by the general formula (a3-12)]

In the above formula (a3-12), R is the same as the description of R in the above formula (a3-1).

P ⁰² , -C(=O)-O- or -C(=O)-NR ⁿ - (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -C(=O)-O- It is better. The alkyl group of R ⁿ is the same as the alkyl group of R.

The cyclic hydrocarbon group in W ⁰² is the same as the aliphatic cyclic group (monocyclic group, polycyclic group) or aromatic hydrocarbon group exemplified in the description of R ⁰ in the above formula (a3-1). The content.

W ⁰² may have an oxygen atom or a sulfur atom at any position, and the description is the same as the description of R ⁰ in the above formula (a3-1).

The following is a preferred specific example of the structural unit represented by the general formula (a3-12). In the following formulae, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

[Structural unit represented by the general formula (a3-13)]

In the above formula (a3-13), R is the same as the description of R in the above formula (a3-1).

P ⁰³ , -C(=O)-O- or -C(=O)-NR ⁿ - (R ⁿ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -C(=O)-O- It is better. The alkyl group of R ⁿ is the same as the alkyl group of R.

The linear hydrocarbon group in W ⁰³ preferably has a carbon number of from 1 to 10, preferably a carbon number of from 1 to 5, more preferably a carbon number of from 1 to 3.

The linear hydrocarbon group in W ⁰³ may further have a substituent (a) other than -OH, -COOH, -CN, -SO ₂ NH ₂ and -CONH ₂ . The substituent (a) is, for example, an alkyl group having 1 to 5 carbon atoms, an aliphatic cyclic group (monocyclic group or polycyclic group), a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. The aliphatic ring group (monocyclic group, polycyclic group) in the substituent (a) preferably has 3 to 30 carbon atoms, preferably 5 to 30, more preferably 5 to 20 carbon atoms. 6~15 is especially good, and 6~12 is the best. Specifically, for example, a group obtained by removing two or more hydrogen atoms from a monocyclic alkane; and removing one or more hydrogen atoms from a polycyclic alkane such as a bicycloalkane, a tricycloalkane or a tetracycloalkane; Base and so on. More specifically, for example, a group obtained by removing two or more hydrogen atoms from a monocyclic alkane such as cyclopentane or cyclohexane; from adamantane, norbornane, isodecane, tricyclodecane, tetracyclic A group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as dodecane.

Further, the linear hydrocarbon group in W ⁰³ may, for example, be a structural unit represented by the following general formula (a3-13-a), and may have a plurality of substituents (a) or a plurality of substituents (a) They can also be bonded to each other to form a ring.

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. R ^a1 and R ^a2 are each independently an alkyl group having 1 to 5 carbon atoms, an aliphatic cyclic group (monocyclic group or polycyclic group), a fluorine atom, or a fluorinated alkyl group having 1 to 5 carbon atoms. However, R ^a1 and R ^a2 may be bonded to each other to form a ring. q ⁰ is an integer from 1 to 4].

In the above formula (a3-13-a), R is the same as the description of R in the above formula (a3-1).

The aliphatic cyclic group (monocyclic group or polycyclic group) in R ^a1 and R ^a2 and the aliphatic cyclic group (monocyclic group or polycyclic group) in the above substituent (a) are The same content.

Further, R ^a1 and R ^a2 may be bonded to each other to form a ring. In this case, R ^a1 , and R ^a2 , and a carbon atom to which R ^a1 and R ^a2 are bonded together form a ring group. The cyclic group may be a monocyclic group or a polycyclic group, and specifically, for example, an aliphatic cyclic group (monocyclic group or polycyclic group) in the above substituent (a) The monocyclic alkane or polycyclic alkane exemplified in the description is a group obtained by removing one or more hydrogen atoms.

It is preferable that q ⁰ is 1 or 2, and 1 is more preferable.

The following is a preferred specific example of the structural unit represented by the general formula (a3-13). In the following formulae, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

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

(A1) The composition has the structural unit (a3), and the proportion of the structural unit (a3) is preferably 0 to 85 mol%, and 0 to 80 mol, relative to the total structural unit constituting the (A1) component. % is better. When the ratio of the structural unit (a3) is equal to or greater than the lower limit value, when the structural unit (a3) is contained, sufficient effects (analytical properties, lithographic etching characteristics, and pattern shape enhancement effects) can be obtained, and when the ratio is equal to or less than the upper limit value It is easy to obtain a balance with other structural units.

(other structural units)

The component (A1) may further contain other structural units (hereinafter also referred to as structural units (a4)) other than the structural units (a1) to (a3) insofar as the effects of the present invention are not impaired.

The structural unit (a4) is not limited to any other structural unit that is not classified into the structural units (a1) to (a3) described above, and may be used in an ArF excimer laser or a KrF excimer. A plurality of conventionally known structural units used for resistive resins such as shots (preferably for ArF excimer lasers).

The structural unit (a4), for example, a structural unit derived from an acrylate in which a hydrogen atom bonded to a carbon atom of the α-position can be substituted by a substituent, and a structure containing a non-acid dissociable aliphatic polycyclic group The unit, the structural unit derived from the styrene monomer, and the structural unit derived from the vinyl naphthalene monomer are preferred. The polycyclic group is, for example, the same as exemplified in the case of the structural unit (a1) described above, and can be used for a conventionally known ArF excimer laser or KrF excimer laser (preferably ArF excimer laser Most of the components used in the resin composition of the photoresist composition.

In particular, when at least one selected from the group consisting of a tricyclic fluorenyl group, an adamantyl group, a tetracyclododecyl group, an isodecyl group, and a fluorenyl group is preferable, it is preferable from the viewpoint of industrial availability. The polycyclic group may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.

The structural unit (a4) may specifically be, for example, a structural unit of the following general formulae (a4-1) to (a4-5).

[wherein R is the same as the above].

The structural unit (a4) may be used singly or in combination of two or more.

(A1) In the case where the component contains the structural unit (a4), the ratio of the structural unit (a4) is preferably 1 to 20 mol%, and 1 to 15 mol, based on the total of the total structural units constituting the component (A1). The ear % is preferably, preferably 1 to 10 mol%.

The component (A1) is preferably a copolymer having a structural unit (a1).

The copolymer, for example, a copolymer formed of structural unit (a1) and structural unit (a3); a copolymer formed of structural units (a1) and (a2); and structural units (a1), (a2) And the copolymer formed by (a3); by structural units (a1), (a2), (a3) and (a4) The copolymer formed and the like are exemplified.

The component (A1) in the present invention is particularly preferably a combination of structural units (a11), (a2 ^L ) and (a3), and the above formulae (a1-0-12), (a2-1) and (a3). -12) The combination of the structural units indicated; the combination of the structural units represented by the above formulas (a1-0-13), (a2-1), (a2-3) and (a3-12) is more preferable.

(A1) The mass average molecular weight (Mw) of the component (the polystyrene conversion standard of the gel permeation chromatography analyzer) is not particularly limited, and is generally preferably from 1,000 to 50,000, preferably from 1,500 to 30,000. It is better to use 2500~20000, and 2500~15000 is the best. When the amount is less than or equal to the upper limit of the range, when used as a photoresist, sufficient solubility is obtained for the photoresist solvent. When the value is at least the lower limit of the range, good dry etching resistance or photoresist pattern can be obtained. Section shape.

Further, the degree of dispersion (Mw/Mn) of the component (A1) is not particularly limited, and is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

Further, Mn represents a number average molecular weight.

In the component (A), the component (A1) may be used singly or in combination of two or more.

The ratio of the component (A1) in the component (A) is preferably 25% by mass or more based on the total mass of the component (A), preferably 50% by mass, more preferably 75% by mass, or more preferably 100% by mass. When the ratio is 25% by mass or more, effects such as lithography characteristics can be improved.

[(A2) ingredients]

The component (A2) is, for example, an acid dissociable group having a molecular weight of 500 or more and less than 4,000 and having the above-mentioned (A1) component, and a hydrophilic group-based low molecular compound. Specifically, for example, a part of a hydrogen atom in a hydroxyl group of a compound having a plural phenol skeleton is substituted by the above acid dissociable group.

(A2) component, for example, a sensitizer in a g-line or i-line photoresist known as a non-chemically amplified type, or a part of a hydrogen atom in a hydroxyl group of a low molecular weight phenol compound as a heat-resistant enhancer It is preferred to be replaced by the above acid-dissociable group, and any of these components may be used arbitrarily.

The low molecular weight phenol compound, for example, bis(4-hydroxyphenyl)methane, bis(2,3,4-trihydroxyphenyl)methane, 2-(4-hydroxyphenyl)-2-(4'-hydroxyl Phenyl)propane, 2-(2,3,4-trihydroxyphenyl)-2-(2',3',4'-trihydroxyphenyl)propane, tris(4-hydroxyphenyl)methane, double (4-hydroxy-3,5-dimethylphenyl)-2-hydroxyphenylmethane, bis(4-hydroxy-2,5-dimethylphenyl)-2-hydroxyphenylmethane, bis (4 -hydroxy-3,5-dimethylphenyl)-3,4-dihydroxyphenylmethane, bis(4-hydroxy-2,5-dimethylphenyl)-3,4-dihydroxyphenylmethane , bis(4-hydroxy-3-methylphenyl)-3,4-dihydroxyphenylmethane, bis(3-cyclohexyl-4-hydroxy-6-methylphenyl)-4-hydroxyphenylmethane , bis(3-cyclohexyl-4-hydroxy-6-methylphenyl)-3,4-dihydroxyphenylmethane, 1-[1-(4-hydroxyphenyl)isopropyl]-4-[ 1,2-bis(4-hydroxyphenyl)ethyl]benzene, phenol, m-cresol, p-cresol or xylenol, phenolic valerine condensate 2-6 nucleus, and the like. Of course, it is not limited to this content. In particular, phenolic compounds having 2 to 6 triphenylmethane skeletons It is preferred that it has excellent resolution, LWR, and the like.

The acid dissociable group is also not particularly limited, and can be, for example, the above.

The component (A2) may be used singly or in combination of two or more.

In the photoresist composition of the present invention, the component (A) may be used singly or in combination of two or more.

Among the above, the component (A) preferably contains the component (A1).

In the photoresist composition of the present invention, the content of the component (A) may be appropriately adjusted in accordance with the thickness of the photoresist film to be formed.

<(B) ingredients>

The component (B) is not particularly limited, and those which have been proposed so far as acid generators for chemically amplified photoresists can be used. These acid generators have heretofore been known as sulfonium-based acid generators such as sulfonium salts or phosphonium salts, sulfonate-based acid generators, dialkyl or bisarylsulfonyldiazomethanes, and poly (disulfonyl) diazomethane acid generator such as diazomethane, nitrobenzyl sulfonate acid generator, iminosulfonate acid generator, diterpenoid acid generator and the like .

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

[wherein, R ^1" to R ^3" and R ^5" to R ^6" represent an aryl group, an alkyl group or an alkenyl group which may independently have a substituent. Among the R ^1" to R ^3" in the formula (b-1), any two of them may be bonded to each other and may form a ring together with the sulfur atom in the formula. R ^4" represents an alkyl group, a halogenated alkyl group, an aryl group, or an alkenyl group which may have a substituent.

In the formula (b-1), R ^1" to R ^3" represent an aryl group, an alkyl group or an alkenyl group which may independently have a substituent. Any one of R ^1" to R ^{3 "} may be bonded to each other and may form a ring together with a sulfur atom in the formula.

Further, even the viewpoint of improving the lithography characteristics of the resist pattern shape, among R ^{1 "~} R ^3", at least one aryl group is preferable, and R ^{1 "~} R ^3" in order to Two or more aryl groups are preferred, and all of R ^1" to R ^3" are particularly preferably aryl groups.

The aryl group of R ^1" to R ^3" may be an unsubstituted aryl group having 6 to 20 carbon atoms; a part or all of a hydrogen atom of the unsubstituted aryl group may be an alkyl group, an alkoxy group or a halogen atom. , hydroxy, keto (=O), aryl, alkoxyalkyloxy, alkoxycarbonylalkyloxy, -C(=O)-OR ^6' , -OC(=O)-R ^7' , a substituted aryl group or the like substituted by -OR ^8' or the like. R ^{6 '} , R ^{7 '} , and R ^{8 '} each represent a linear, branched or cyclic hydrocarbon group having a carbon number of 1 to 25 or a linear chain having a carbon number of 2 to 5; A branched or branched aliphatic unsaturated hydrocarbon group.

In the case of R ^1" to R ^3" , an unsubstituted aryl group can be inexpensively synthesized, and an aryl group having 6 to 10 carbon atoms is preferred. Specifically, for example, a phenyl group, a naphthyl group or the like.

The alkyl group as a substituent in the substituted aryl group of R ^1" to R ^3" is preferably an alkyl group having 1 to 5 carbon atoms, and a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group. For the best.

The alkoxy group as a substituent in the substituted aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, and an n-butoxy group. The base and tert-butoxy group are the most preferred.

The halogen atom as a substituent in the substituted aryl group is preferably a fluorine atom.

The aryl group as a substituent in the substituted aryl group is, for example, the same as the aryl group of the above R ^1" to R ^3" , and preferably an aryl group having 6 to 20 carbon atoms, and a carbon number of 6 to 10 The aryl group is preferred, and the phenyl group and the naphthyl group are more preferred.

Substituting an alkoxyalkyloxy group in the aryl group, for example, the formula: -OC(R ⁴⁷ )(R ⁴⁸ )-OR ⁴⁹

In the formula, R ⁴⁷ and R ⁴⁸ are each a hydrogen atom or a linear or branched alkyl group, and R ⁴⁹ is an alkyl group.

In R ⁴⁷ and R ⁴⁸ , the alkyl group preferably has 1 to 5 carbon atoms, and may be either linear or branched, preferably ethyl or methyl, and preferably methyl. .

R ⁴⁷ and R ⁴⁸ are preferably at least one of hydrogen atoms. In particular, one is a hydrogen atom, and the other is preferably a hydrogen atom or a methyl group.

The alkyl group of R ⁴⁹ is preferably one having a carbon number of from 1 to 15, and may be any of a linear chain, a branched chain, and a cyclic group.

The linear or branched alkyl group in R ⁴⁹ is preferably a carbon number of 1 to 5, and examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, and a tert-butyl group.

The cyclic alkyl group in R ⁴⁹ is preferably a carbon number of 4 to 15, preferably a carbon number of 4 to 12, and a carbon number of 5 to 10. Specifically, for example, it is substituted by an alkyl group having 1 to 5 carbon atoms, a fluorine atom or a fluorinated alkyl group, or an unsubstituted monocyclic alkane, a bicycloalkane, a tricycloalkane, or a tetra A group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as a cycloalkane. Monocyclic alkane is, for example, cyclopentane, cyclohexane or the like. Polycyclic alkanes are, for example, adamantane, norbornane, isodecane, tricyclodecane, tetracyclododecane, and the like. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferred.

Substituting an alkoxycarbonylalkyloxy group in the aryl group, for example, the formula: -OR ⁵⁰ -C(=O)-OR ⁵⁶

[wherein, R ⁵⁰ is a linear or branched alkyl group, and R ⁵⁶ is a tertiary alkyl group].

a linear or branched alkyl group in R ⁵⁰ having a carbon number of 1 to 5, for example, a methyl group, an ethyl group, a trimethyl group, a tetramethyl group, a 1,1-di group. Methyl extended ethyl and the like.

A tertiary alkyl group in R ⁵⁶ , for example, 2-methyl-2-adamantyl, 2-ethyl-2-adamantyl, 1-methyl-1-cyclopentyl, 1-ethyl-1 -cyclopentyl, 1-methyl-1-cyclohexyl, 1-ethyl-1-cyclohexyl, 1-(1-adamantyl)-1-methylethyl, 1-(1-adamantyl) -1-methylpropyl, 1-(1-adamantyl)-1-methylbutyl, 1-(1-adamantyl)-1-methylpentyl; 1-(1-cyclopentyl) 1-methylethyl, 1-(1-cyclopentyl)-1-methylpropyl, 1-(1-cyclopentyl)-1-methylbutyl, 1-(1-cyclo Pentyl)-1-methylpentyl; 1-(1-cyclohexyl)-1-methylethyl, 1-(1-cyclohexyl)-1-methylpropyl, 1-(1-cyclohexyl -1-methylbutyl, 1-(1-cyclohexyl)-1-methylpentyl, tert-butyl, tert-pentyl, tert-hexyl, and the like.

Further, for example, the above formula: -OR ⁵⁰ -C(=O)-OR ⁵⁶ is a group in which R ⁵⁶ is substituted by R ^56' . R ^{56 'is,} may contain a hydrogen atom, an alkyl group, fluorinated alkyl, hetero atoms or aliphatic cyclic group.

The alkyl group in R ^{56 '} is, for example, the same as the alkyl group of the above R ⁴⁹ and the like.

The fluorinated alkyl group in R ^56' is a group in which a part or the whole of a hydrogen atom in the alkyl group of R ⁴⁹ is substituted by a fluorine atom.

In R ^{56 '} , an aliphatic cyclic group which may contain a hetero atom, for example, an aliphatic cyclic group which does not contain a hetero atom, an aliphatic cyclic group which contains a hetero atom in a ring structure, and hydrogen in an aliphatic cyclic group The atom is replaced by a hetero atom.

In R ^{56 '} , an aliphatic cyclic group which does not contain a hetero atom, for example, one or more hydrogen atoms are removed from a monocyclic alkane, a polycyclic alkane such as a bicycloalkane, a tricycloalkane or a tetracycloalkane. The basis of the atom, etc. Monocyclic alkane is, for example, cyclopentane, cyclohexane or the like. Polycyclic alkanes are, for example, adamantane, norbornane, isodecane, tricyclodecane, tetracyclododecane, and the like. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferred.

In R ^{56 '} , the ring structure contains an aliphatic ring group of a hetero atom, and specifically, for example, a group represented by the formulas (L1) to (L6), (S1) to (S4) which will be described later.

In R ^{56 '} , a hydrogen atom in the aliphatic cyclic group is substituted by a hetero atom, and specifically, for example, a hydrogen atom in the aliphatic cyclic group is replaced by an oxygen atom (=O).

^{-C (= O) -OR 6 '} , -OC (= O) -R 7', -OR 8 ' in the ^{R 6', R 7 ',} R 8', each represents a straight-chain carbon atoms of 1 to 25 a saturated hydrocarbon group having a cyclic or branched shape or a carbon number of 3 to 20, or a linear or branched aliphatic unsaturated hydrocarbon group having 2 to 5 carbon atoms.

a linear or branched saturated hydrocarbon group having a carbon number of 1 to 25 in terms of carbon number 1~15 is better, 4~10 is better.

A linear saturated hydrocarbon group, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a decyl group or the like.

Branched saturated hydrocarbon group, in addition to tertiary alkyl group, for example, 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl , 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, etc. .

The aforementioned linear or branched saturated hydrocarbon group may have a substituent. The substituent is, for example, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O), a cyano group, a carboxyl group or the like.

The alkoxy group as a substituent of the above-mentioned linear or branched saturated hydrocarbon group is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, an ethoxy group, an n-propoxy group, or an iso- A propoxy group, an n-butoxy group, and a tert-butoxy group are preferred, and a methoxy group and an ethoxy group are preferred.

The halogen atom as a substituent of the linear or branched saturated hydrocarbon group, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like is preferably a fluorine atom.

a halogenated alkyl group as a substituent of the above-mentioned linear or branched saturated hydrocarbon group, for example, a part or all of a hydrogen atom of the above-mentioned linear or branched saturated hydrocarbon group is substituted by the aforementioned halogen atom Wait.

The cyclic saturated hydrocarbon group having 3 to 20 carbon atoms in R ^{6 '} , R ^{7 '} and R ^{8 '} may be any of a polycyclic group or a monocyclic group, for example, a monocyclic alkane. A group obtained by removing one hydrogen atom; a group obtained by removing one hydrogen atom from a polycyclic alkane such as a bicycloalkane, a tricycloalkane or a tetracycloalkane. More specifically, for example, a monocyclic alkane such as cyclopentane, cyclohexane, cycloheptane or cyclooctane, or adamantane, norbornane, isodecane, tricyclodecane or tetracyclic A group obtained by removing one hydrogen atom such as a polycyclic alkane such as an alkane.

The cyclic saturated hydrocarbon group may have a substituent. For example, a part of a carbon atom constituting a ring of the cyclic alkyl group may be substituted by a hetero atom, and a hydrogen atom bonded to a ring of the cyclic alkyl group may be substituted with a substituent.

In the former example, for example, one or more of the carbon atoms constituting the ring of the monocyclic alkane or the polycyclic alkane are substituted with one or more heterocycloalkanes substituted with a hetero atom such as an oxygen atom, a sulfur atom or a nitrogen atom. The base obtained by the hydrogen atom or the like. Further, the structure of the ring may have an ester bond (-C(=O)-O-). Specifically, for example, a lactone-containing monocyclic group such as a group obtained by removing one hydrogen atom from γ-butyrolactone, or a bicycloalkane having a lactone ring, a tricycloalkane or a tetracyclic chain A polycyclic group containing a lactone such as a group obtained by removing one hydrogen atom from an alkane.

The substituent in the latter example may be the same as the substituent exemplified as the substituent which the linear or branched alkyl group may have, and may be, for example, a lower alkyl group.

Further, R ^6' , R ^7' and R ^8' may be a linear or branched alkyl group in combination with a cyclic alkyl group.

a combination of a linear or branched alkyl group and a cyclic alkyl group, for example, a linear or branched alkyl group bonded to a cyclic alkyl group as a substituent, a cyclic alkyl group A group obtained by bonding a linear or branched alkyl group as a substituent.

A linear aliphatic unsaturated hydrocarbon group in R ^{6 '} , R ^{7 '} or R ^{8 '} , for example, a vinyl group, a propenyl group, a butenyl group or the like.

A branched aliphatic unsaturated hydrocarbon group in R ^{6 '} , R ^{7 '} and R ^8' , for example, a 1-methylpropenyl group, a 2-methylpropenyl group or the like.

The linear or branched aliphatic unsaturated hydrocarbon group may have a substituent. The substituent is the same as those exemplified for the substituent which the linear or branched alkyl group may have.

Among the above, R ^{7 '} and R ^{8 '} are a linear or branched saturated hydrocarbon group having a carbon number of 1 to 15 from the viewpoint of further improving the lithographic etching property and the photoresist pattern shape. Or a cyclic saturated hydrocarbon group having a carbon number of 3 to 20 is preferred.

The aryl group of R ^1" to R ^3" is preferably a phenyl group or a naphthyl group.

The alkyl group of R ^1" to R ^3" is, for example, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms. Among them, the viewpoint of excellent resolution is preferably 1 to 5 carbon atoms. Specifically, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, cyclopentyl, hexyl, cyclohexyl, decyl, decyl, etc. Further preferred substituents having excellent analytical properties or inexpensive synthesis can be exemplified by a methyl group.

The alkenyl group of R ^1" to R ^3" is preferably 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, and still more preferably 2 to 4 carbon atoms. Specifically, for example, a vinyl group, a propenyl group (allyl group), a butenyl group, a 1-methylpropenyl group, a 2-methylpropenyl group, or the like.

The alkyl or alkenyl group of R ^1" to R ^3" may be an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, a keto group (=O), an aryl group, an alkoxyalkyloxy group or an alkoxycarbonyl group. A substituted alkyl group or a substituted alkenyl group substituted with an alkyloxy group, -C(=O)-OR ^6' , -OC(=O)-R ^7' or -OR ^8' may be used. These substituents have, for example, the substituents which the above substituted aryl group may have the same content.

Among R ^1" to R ^3" , any two of them are bonded to each other and form a ring together with the sulfur atom in the formula, and include a sulfur atom to form a 3 to 10 member ring to form a 5 to 7 member. The ring is especially good.

Among R ^1" to R ^3" , any two of them are bonded to each other and form a ring together with the sulfur atom in the formula, and one of them remains, and an aryl group is preferred. The aryl group is the same as the aryl group of the above R ^1" to R ^3" .

Specific examples of the cation moiety in the compound represented by the above formula (b-1), for example, triphenylsulfonium, (3,5-dimethylphenyl)diphenylphosphonium, (4-(2-adamantane) Oxymethylmethyl)-3,5-dimethylphenyl)diphenylanthracene, (4-(2-adamantyloxymethyloxy)phenyl)diphenylphosphonium, (4-( Tert-butoxycarbonylmethyloxy)phenyl)diphenylphosphonium, (4-(tert-butoxycarbonylmethyloxy)-3,5-dimethylphenyl)diphenylphosphonium, (4-(2-Methyl-2-adamantyloxycarbonylmethyloxy)phenyl)diphenylphosphonium, (4-(2-methyl-2-adamantyloxycarbonylmethyloxy)) -3,5-dimethylphenyl)diphenylanthracene, tris(4-methylphenyl)anthracene, dimethyl(4-hydroxynaphthyl)anthracene, monophenyldimethylhydrazine, diphenyl Monomethyl hydrazine, (4-methylphenyl) diphenyl fluorene, (4-methoxyphenyl) diphenyl fluorene, tris(4-tert-butyl)phenyl fluorene, diphenyl (1 -(4-methoxy)naphthyl)anthracene, bis(1-naphthyl)phenylanthracene, 1-phenyltetrahydrothiophene, 1-(4-methylphenyl)tetrahydrothiophene, 1- (3,5-Dimethyl-4-hydroxyphenyl)tetrahydrothiophene oxime, 1-(4-methoxynaphthalen-1-yl)tetrahydrothiophene oxime, 1-(4-ethoxynaphthalene-1 -yl)tetrahydrothiophene, 1-(4-n-butoxynaphthalene-1- Tetrahydrothiophene oxime, 1-phenyltetrahydrothiopyranium, 1-(4-hydroxyphenyl)tetrahydrothiopyran, 1-(3,5-dimethyl-4-hydroxyphenyl)tetra Hydrothiazolidine, 1-(4-methylphenyl)tetrahydrothiopyrene, and the like.

In addition, as for the more suitable one of the cations in the compound represented by the formula (b-1), specifically, the contents shown below are as follows.

[wherein, g1 represents a repeating unit, an integer of 1 to 5].

[wherein, g2 and g3 represent repeating units, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20].

In the formula (b-1), R ^4" represents an alkyl group, a halogenated alkyl group, an aryl group or an alkenyl group which may have a substituent.

The alkyl group in R ^4" may be any of a linear chain, a branched chain or a cyclic chain.

The linear or branched alkyl group is preferably a carbon number of 1 to 10, preferably a carbon number of 1 to 8, and preferably a carbon number of 1 to 4.

The cyclic alkyl group is preferably a carbon number of 4 to 15, preferably a carbon number of 4 to 10, and a carbon number of 6 to 10.

The halogen atom R ⁴ halogenated alkyl group ^"in the, for example, the linear, a part of hydrogen atoms of branched or cyclic alkyl group of or all group substituted with the halogen atom and the like, e.g., fluoro An atom, a chlorine atom, a bromine atom, an iodine atom, etc., preferably a fluorine atom.

In the halogenated alkyl group, the ratio of the number of halogen atoms (halogenation ratio (%)) to the total number of halogen atoms and hydrogen atoms contained in the halogenated alkyl group is preferably from 10 to 100%, and from 50 to 100%. Good, 100% is the best. When the halogenation rate is higher, the stronger the strength of the acid, the more preferable.

The aryl group in the above R ^4" is preferably an aryl group having 6 to 20 carbon atoms.

The alkenyl group in the above R ^4" is preferably an alkenyl group having 2 to 10 carbon atoms.

In the above R ^4" , "may have a substituent" means a part or all of a hydrogen atom in the above linear, branched or cyclic alkyl group, halogenated alkyl group, aryl group or alkenyl group. It may also be substituted by a substituent (other than a hydrogen atom or a base).

The number of the substituents in R ^4" may be one or two or more.

The above substituent, for example, a halogen atom, a hetero atom, an alkyl group, a hydroxyl group, a formula: X ³ -Q ¹ - [wherein, Q ¹ is a divalent bond group containing an oxygen atom, and X ³ may have a substituent. The base represented by the hydrocarbon group of 3 to 30 carbon atoms.

The halogen atom or the alkyl group is the same as the halogen atom or the alkyl group in the halogenated alkyl group in R ^4" .

The aforementioned hetero atom is, for example, an oxygen atom, a nitrogen atom, a sulfur atom or the like.

In the group represented by X ³ -Q ¹ -, Q ¹ is a divalent bond group containing an oxygen atom.

Q ¹ may contain atoms other than oxygen atoms. An atom other than an oxygen atom, for example, a carbon atom, a hydrogen atom, an oxygen atom, a sulfur atom, a nitrogen atom or the like.

a divalent bond group containing an oxygen atom, for example, an oxygen atom (ether bond; -O-), an ester bond (-C(=O)-O-), a guanamine bond (-C(=O) a non-hydrocarbon oxygen atom-containing bond group such as -NH-), a carbonyl group (-C(=O)-), a carbonate bond (-OC(=O)-O-); a combination of a bonding group of an oxygen atom and an alkyl group.

The combination, for example, -R ⁹¹ -O-, -R ⁹² -OC(=O)-, -C(=O)-OR ⁹³ -OC(=O)- (wherein, R ⁹¹ to R ⁹³ are each Independent alkyl group) and the like.

The alkylene group in R ⁹¹ to R ⁹³ is preferably a linear or branched alkyl group. The carbon number of the alkyl group is preferably from 1 to 12, preferably from 1 to 5, and is 1 ~3 is especially good.

The alkylene group, specifically, for example, methyl [-CH ₂ -]; -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C (CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, -C(CH ₂ CH ₃ ) ₂ - and the like alkyl-extension methyl; ex-ethyl [-CH ₂ CH ₂ -]; -CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -isoalkyl extended ethyl; trimethyl (n-propyl)[-CH ₂ CH ₂ CH ₂ -]; -CH(CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ -isoalkyl extended trimethyl; tetramethyl [-CH ₂ CH ₂ CH ₂ CH ₂ -]; -CH(CH ₃ )CH ₂ CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ CH ₂ -Isoalkylalkyltetramethyl; pentamethyl [-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -] and the like.

Q ¹ , preferably a divalent bond group containing an ester bond or an ether bond, wherein -R ⁹¹ -O-, -R ⁹² -OC(=O)- or -C(=O)- OR ⁹³ -OC(=O)- is preferred.

In the group represented by X ³ -Q ¹ -, the hydrocarbon group of X ³ may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group.

The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring. The carbon number of the aromatic hydrocarbon group is preferably from 3 to 30, preferably from 5 to 30, more preferably from 5 to 20, most preferably from 6 to 15, and most preferably from 6 to 12. However, among the carbon numbers, those having no carbon number in the substituent are included.

The aromatic hydrocarbon group is specifically obtained, for example, by removing one hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group or a phenanthryl group. An aralkyl group such as an aryl group, a benzyl group, a phenylethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group or a 2-naphthylethyl group. The number of carbon atoms in the alkyl chain in the aralkyl group is preferably from 1 to 4, more preferably from 1 to 2, particularly preferably from 1 to 1.

The aromatic hydrocarbon group may have a substituent. For example, a part of a carbon atom constituting an aromatic ring of the aromatic hydrocarbon group may be substituted by a hetero atom, and a hydrogen atom bonded to an aromatic ring of the aromatic hydrocarbon group may be substituted by a substituent or the like.

In the former, for example, a heteroaryl group in which a part of a carbon atom constituting the ring of the aryl group is substituted with a hetero atom such as an oxygen atom, a sulfur atom or a nitrogen atom, and a carbon constituting a ring of an aromatic hydrocarbon in the aralkyl group; A heteroarylalkyl group in which a part of an atom is substituted by the aforementioned hetero atom.

The latter exemplifies a substituent of the aromatic hydrocarbon group in the latter, for example, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O), or the like.

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

The alkoxy group as a substituent of the aromatic hydrocarbon group is preferably an alkoxy group having 1 to 5 carbon atoms, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, and an n-butyl group. The oxy group and the tert-butoxy group are preferred, and the methoxy group and the ethoxy group are preferred.

The halogen atom as the substituent of the aromatic hydrocarbon group, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

The halogenated alkyl group as a substituent of the aromatic hydrocarbon group is, for example, a group in which a part or all of a hydrogen atom of the alkyl group is substituted by the halogen atom.

The aliphatic hydrocarbon group in X ³ may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. Further, the aliphatic hydrocarbon group may be any of a linear chain, a branched chain, and a cyclic chain.

In X ³ , in the aliphatic hydrocarbon group, a part of a carbon atom constituting the aliphatic hydrocarbon group may be substituted by a substituent containing a hetero atom, and a part or all of hydrogen atoms constituting the aliphatic hydrocarbon group may be contained in a hetero atom. Substituents can also be substituted.

The "hetero atom" in X ³ is not particularly limited as long as it is an atom other than a carbon atom or a hydrogen atom, and examples thereof include a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom. A halogen atom, for example, a fluorine atom, a chlorine atom, an iodine atom, a bromine atom or the like.

The substituent containing a hetero atom may be a group consisting of only the above-mentioned hetero atom, and may contain a group other than the above-mentioned hetero atom or an atom.

Substituting a substituent of a part of carbon atoms, specifically, for example, -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, -C (=O)-NH-, -NH- (H can be substituted by a substituent such as an alkyl group or a fluorenyl group), -S-, -S(=O) ₂ -, -S(=O) ₂ -O- Wait. In the case where the aliphatic hydrocarbon group is cyclic, the substituents may be included in the ring structure.

A substituent which substitutes a part or all of a hydrogen atom, specifically, for example, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxyl group, an oxygen atom (=O), a cyano group or the like.

The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, and is a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group or a tert-butoxy group. Preferably, methoxy and ethoxy groups are preferred.

The halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom.

The halogenated alkyl group is an alkyl group having 1 to 5 carbon atoms, for example, a part or all of hydrogen atoms in an alkyl group such as a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group. A group substituted by a halogen atom or the like.

The aliphatic hydrocarbon group is preferably a linear or branched saturated hydrocarbon group, a linear or branched monovalent unsaturated hydrocarbon group, or a cyclic aliphatic hydrocarbon group (aliphatic cyclic group).

The linear saturated hydrocarbon group (alkyl group) preferably has a carbon number of 1 to 20, preferably 1 to 15, and preferably 1 to 10. Specifically, for example, A Base, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, decyl, undecyl, dodecyl, tridecyl, isotridecyl, ten Tetraalkyl, pentadecyl, hexadecyl, isohexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, icosyl, docosane Base.

The branched saturated hydrocarbon group (alkyl group) preferably has a carbon number of 3 to 20, preferably 3 to 15 and most preferably 3 to 10. Specifically, for example, 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1- Ethyl butyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, and the like.

The unsaturated hydrocarbon group preferably has a carbon number of 2 to 10, preferably 2 to 5, preferably 2 to 4, and particularly preferably 3. A linear monovalent unsaturated hydrocarbon group, for example, a vinyl group, a propenyl group, a butenyl group or the like. A branched monovalent unsaturated hydrocarbon group, for example, a 1-methylpropenyl group, a 2-methylpropenyl group or the like.

The unsaturated hydrocarbon group is particularly preferably an propylene group among the above.

The aliphatic cyclic group may be a monocyclic group or a polycyclic group. The carbon number is preferably 3 to 30, preferably 5 to 30, more preferably 5 to 20, and 6 to 15 is preferred, and 6 to 12 is the best.

Specifically, for example, a group obtained by removing one or more hydrogen atoms from a monocyclic alkane; and removing one or more hydrogen atoms from a polycyclic alkane such as a bicycloalkane, a tricycloalkane or a tetracycloalkane; Base and so on. More specifically, for example, a group obtained by removing one or more hydrogen atoms from a monocyclic alkane such as cyclopentane or cyclohexane; adamantane, norbornane, isodecane, tricyclodecane, tetracyclic twelve A group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as an alkane.

An aliphatic cyclic group having no ring-containing substituents in the ring structure, and the aliphatic ring group is preferably a polycyclic group, and one or more hydrogen atoms are removed from the polycyclic alkane. The base is preferably a group obtained by removing one or more hydrogen atoms from adamantane.

An aliphatic cyclic group having a substituent containing a hetero atom in the ring structure, the substituent containing a hetero atom, -O-, -C(=O)-O-, -S-, -S( =O) ₂ -, -S(=O) ₂ -O- is preferred. Specific examples of the aliphatic cyclic group include, for example, the following formulae (L1) to (L6), (S1) to (S4), and the like.

[wherein Q" is an alkylene group having 1 to 5 carbon atoms, -O-, -S-, -OR ⁹⁴ - or -SR ⁹⁵ -, and R ⁹⁴ and R ⁹⁵ are each independently a carbon number of 1 to 5 An alkyl group, m is an integer of 0 or 1.

Wherein, Q ", R ⁹⁴ and R ⁹⁵ in the alkylene group, respectively, and the R ⁹¹ ~ R ⁹³ in the alkylene group is of the same content.

In the aliphatic cyclic group, a part of a hydrogen atom to which a carbon atom constituting the ring structure is bonded may be substituted with a substituent. The substituent, for example, An alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O), or the like.

The alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, particularly preferably a methyl group, an ethyl group, a propyl group, an n-butyl group or a tert-butyl group.

The alkoxy group and the halogen atom respectively have the same contents as those of the substituent of the aliphatic hydrocarbon group of the above X ³ which may be substituted for a part or all of the hydrogen atoms.

In the present invention, X ^{3 is} preferably a cyclic group which may have a substituent. The cyclic group may be an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, and an aliphatic cyclic group which may have a substituent.

The aromatic hydrocarbon group is preferably a naphthyl group which may have a substituent or a phenyl group which may have a substituent.

The aliphatic cyclic group which may have a substituent is preferably a polycyclic aliphatic ring group which may have a substituent. The polycyclic aliphatic cyclic group is preferably a group obtained by removing one or more hydrogen atoms from the polycyclic alkane, and the above (L2) to (L6), (S3) to (S4), and the like.

In the present invention, R ^{4" is} preferably one having X ³ -Q ¹ - as a substituent. In this case, R ^{4" is} represented by X ³ -Q ¹ -Y ¹⁰ -[wherein, Q ¹ and X ³ is the same as the above, and Y ¹⁰ is preferably a group represented by a C 1-4 alkyl group which may have a substituent or a fluorinated alkyl group having 1 to 4 carbon atoms which may have a substituent.

In the group represented by X ³ -Q ¹ -Y ¹⁰ -, the alkylene group of Y ¹⁰ is, for example, the same as the carbon number of 1 to 4 in the alkylene group of the above-mentioned Q ¹ .

A fluorinated alkyl group, for example, a group in which a part or all of a hydrogen atom of the alkyl group is substituted by a fluorine atom.

Y ¹⁰ , specifically, for example, -CF ₂ -, -CF ₂ CF ₂ -, -CF ₂ CF ₂ CF ₂ -, -CF(CF ₃ )CF ₂ -, -CF(CF ₂ CF ₃ )-, - C(CF ₃ ) ₂ -, -CF ₂ CF ₂ CF ₂ CF ₂ -, -CF(CF ₃ )CF ₂ CF ₂ -, -CF ₂ CF(CF ₃ )CF ₂ -, -CF(CF ₃ )CF (CF ₃ )-, -C(CF ₃ ) ₂ CF ₂ -, -CF(CF ₂ CF ₃ )CF ₂ -, -CF(CF ₂ CF ₂ CF ₃ )-, -C(CF ₃ )(CF ₂ CF ₃ )-;-CHF-, -CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ -, -CH ₂ CF ₂ CF ₂ -, -CH(CF ₃ )CH ₂ -, -CH(CF ₂ CF ₃ )-, -C(CH ₃ )(CF ₃ )-, -CH ₂ CH ₂ CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ CF ₂ -, -CH(CF ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CF ₃ )CH ₂ -, -CH(CF ₃ )CH(CF ₃ )-, -C(CF ₃ ) ₂ CH ₂ -; -CH ₂ -, -CH ₂ CH ₂ -, -CH ₂ CH ₂ CH ₂ -, -CH(CH ₃ )CH ₂ -, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -CH ₂ CH ₂ CH ₂ CH ₂ -, -CH ( CH ₃ )CH ₂ CH ₂ -, -CH ₂ CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, -CH(CH ₂ CH ₃ )CH ₂ -, -CH(CH ₂ CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₃ )-, and the like.

Y ^{10 is} preferably a fluorinated alkyl group, and particularly preferably a fluorinated alkyl group obtained by fluorinating a carbon atom bonded to a sulfur atom adjacent thereto. The fluorinated alkyl groups, for example, -CF ₂ -, -CF ₂ CF ₂ -, -CF ₂ CF ₂ CF ₂ -, -CF(CF ₃ )CF ₂ -, -CF ₂ CF ₂ CF ₂ CF ₂ -, -CF(CF ₃ )CF ₂ CF ₂ -, -CF ₂ CF(CF ₃ )CF ₂ -, -CF(CF ₃ )CF(CF ₃ )-, -C(CF ₃ ) ₂ CF ₂ -, -CF(CF ₂ CF ₃ )CF ₂ -; -CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ -, -CH ₂ CF ₂ CF ₂ -; -CH ₂ CH ₂ CH ₂ CF ₂ -, -CH ₂ CH ₂ CF ₂ CF ₂ -, -CH ₂ CF ₂ CF ₂ CF ₂ -, and the like.

Among the more so, on _{-CF 2 -, - CF 2 CF} 2 -, - CF 2 CF 2 CF 2 -, or CH ₂ CF ₂ CF ₂ - preferably to _{-CF 2 -, - CF 2 CF} 2 - or -CF ₂ CF ₂ CF ₂ - is preferred, and -CF ₂ - is particularly preferred.

The aforementioned alkylene or fluorinated alkyl group may have a substituent. The alkyl group or the fluorinated alkyl group has a "substituent group" means that a part or all of a hydrogen atom or a fluorine atom in the alkyl group or the fluorinated alkyl group is a hydrogen atom and an atom other than a fluorine atom. Or the meaning of the base.

The substituent which the alkyl group or the fluorinated alkyl group may have, for example, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group or the like.

In the above formula (b-2), R ^5" to R ^6" represent an aryl group, an alkyl group or an alkenyl group which may independently have a substituent.

Further, even the viewpoint of improving the lithography characteristics of the resist pattern shape, in R ^{5 "~} R ^6", at least one aryl group is preferable, and any one of R ^{5 "~} R ^6" of a person Those who are all aryl are better.

The aryl group of R ^5" to R ^6" is the same as the aryl group of R ^1" to R ^3" .

The alkyl group of R ^5" to R ^6" is the same as the alkyl group of R ^1" to R ^3" .

The alkenyl group of R ^5" to R ^6" is the same as the alkenyl group of R ^1" to R ^3" .

Among these, R ^5" to R ^6" are all preferred as the phenyl group.

Specific examples of the cation moiety in the compound represented by the above formula (b-2) include diphenylphosphonium, bis(4-tert-butylphenyl)fluorene and the like.

(B-2) in the above formula R ^{4 ",} and (b-1) in the above formula R ^4" of the same content.

Specific examples of the sulfonium-based acid generator represented by the formulae (b-1) and (b-2), for example, diphenyl sulfonium trifluoromethanesulfonate or nonafluorobutane sulfonate, bis (4- Tert-butylphenyl) guanidine trifluoromethane sulfonate or nonafluorobutane sulfonate, triphenylsulfonium trifluoromethane sulfonate, heptafluoropropane sulfonate or its nonafluorobutane sulfonate , tris(4-methylphenyl)phosphonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, dimethyl(4-hydroxynaphthyl)phosphonium trifluoromethanesulfonate An acid ester, a heptafluoropropane sulfonate or a nonafluorobutane sulfonate thereof, a triphenylmethanesulfonate of monophenyldimethylhydrazine, a heptafluoropropane sulfonate or a nonafluorobutane sulfonate thereof; Trifluoromethanesulfonate of monomethylhydrazine, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, trifluoromethanesulfonate of (4-methylphenyl)diphenylphosphonium, and heptafluoropropane a sulfonate or a nonafluorobutanesulfonate thereof, a (4-methoxyphenyl)diphenylphosphonium trifluoromethanesulfonate, a heptafluoropropanesulfonate or a nonafluorobutanesulfonate thereof, (4-tert-butyl)phenylhydrazine trifluoromethanesulfonate, Fluoropropane sulfonate or its nonafluorobutane sulfonate, diphenyl(1-(4-methoxy)naphthyl)phosphonium trifluoromethanesulfonate, heptafluoropropane sulfonate or its nonafluorobutane Alkanesulfonate, tris(1-naphthyl)phenylphosphonium trifluoromethanesulfonate, heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1-phenyltetrahydrothiophene trifluoromethane Sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; trifluoromethanesulfonate of 1-(4-methylphenyl)tetrahydrothiophene, its heptafluoropropane sulfonate or its nonafluoro Butane sulfonate; trifluoromethanesulfonate of 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophene, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1-(4-methoxynaphthalen-1-yl) Trifluoromethanesulfonate of tetrahydrothiophene, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; trifluoromethanesulfonate of 1-(4-ethoxynaphthalen-1-yl)tetrahydrothiophene An acid ester, a heptafluoropropane sulfonate or a nonafluorobutane sulfonate thereof; a trifluoromethanesulfonate of 1-(4-n-butoxynaphthalen-1-yl)tetrahydrothiophene hydride, and a heptafluoropropane sulfonic acid Ester or its nonafluorobutane sulfonate; triphenylmethanesulfonate of 1-phenyltetrahydrothiopyrene, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1-(4-hydroxybenzene) Trifluorothiamethane trifluoromethanesulfonate, heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophene A trifluoromethanesulfonate, a heptafluoropropane sulfonate or a nonafluorobutane sulfonate thereof; a trifluoromethanesulfonate of 1-(4-methylphenyl)tetrahydrothiopyranium, a heptafluoropropane thereof a sulfonate or a nonafluorobutane sulfonate thereof.

Further, an anthracene salt in which the anion portion of the onium salt is replaced by an anion portion represented by any one of the following formulas (b1) to (b9) may be used.

[wherein, q1~q2 are independent integers of 1~5, q3 is an integer from 1 to 12, t3 is an integer from 1 to 3, r1~r2 are independent integers of 0~3, g is 1~ An integer of 20, R ⁷ is a substituent, n1~n6 are independent 0 or 1, v0~v6 are independent integers of 0~3, and w1~w6 are independent integers of 0~3, Q" and The foregoing is the same content].

The substituent of R ⁷ is, for example, the same as the substituent which the aliphatic hydrocarbon group may have in the above X ³ and the substituent which the aromatic hydrocarbon group may have.

When the symbol (r1 to r2, w1 to w6) attached to R ⁷ is an integer of 2 or more, the plural R ^{7 of} the compound may be the same or different.

Further, in the above-described general formula (b-1) or (b-2), the anion moiety may be represented by the following formula (b-3) or (b-4). The sulfonium-based acid generator (the cation portion is the same as (b-1) or (b-2)) in which the anion portion is substituted.

[wherein, X" represents a C 2~6 alkyl group in which at least one hydrogen atom is replaced by a fluorine atom; Y", Z" means that at least one hydrogen atom independently substituted by a fluorine atom Alkyl group having 1 to 10 carbon atoms].

X" is a linear or branched alkyl group in which at least one hydrogen atom is replaced by a fluorine atom, and the alkyl group has a carbon number of 2 to 6, preferably a carbon number of 3 to 5, preferably It has a carbon number of 3.

Y", Z" are straight-chain or branched alkyl groups in which at least one hydrogen atom is independently substituted by a fluorine atom, and the alkyl group has a carbon number of 1 to 10, preferably a carbon number of 1~. 7, better for carbon number 1~3.

When the carbon number of the alkyl group of X" or the carbon number of the alkyl group of Y" or Z" is in the range of the above carbon number, the solubility in the resist solvent is further improved, and the smaller the better .

Further, in the alkyl group of X" or the alkyl group of Y" or Z", the more the number of hydrogen atoms substituted by the fluorine atom, the stronger the strength of the acid, and the higher the energy of light of 200 nm or less or The viewpoint of transparency of an electronic wire is preferable.

The ratio of the fluorine atom in the alkyl group or the alkyl group, that is, the fluorination rate, is preferably from 70 to 100%, more preferably from 90 to 100%, and most preferably the total fluorine extension in which all hydrogen atoms are replaced by fluorine atoms. Alkyl or perfluoroalkyl.

Further, the onium salt-based acid generator may be a phosphonium salt having a cation represented by the following formula (b-5) or (b-6) in the cation portion.

Wherein R ⁸¹ to R ⁸⁶ are each independently an alkyl group, an ethyl group, an alkoxy group, a carboxyl group, a hydroxyl group or a hydroxyalkyl group; n ₁ to n ₅ are each an integer of 0 to 3 independently, and n ₆ is An integer from 0 to 2.].

In R ⁸¹ to R ⁸⁶ , the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, wherein a linear or branched alkyl group is preferred, and a methyl group, an ethyl group, a propyl group and an isopropyl group are preferred. , n-butyl, or tert-butyl is particularly preferred.

The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, and a linear or branched alkoxy group is preferred, and a methoxy group or an ethoxy group is particularly preferred.

The hydroxyalkyl group is preferably a group obtained by substituting one of the above alkyl groups or a plurality of hydrogen atoms with a hydroxyl group, for example, a methylol group, a hydroxyethyl group, a hydroxypropyl group or the like.

When the symbols n ₁ to n ₆ attached to R ⁸¹ to R ⁸⁶ are integers of 2 or more, the plural numbers R ⁸¹ to R ⁸⁶ may be the same or different.

n _{1 is} preferably 0 to 2, more preferably 0 or 1, more preferably 0.

n ₂ and n _{3 are} preferably each independently 0 or 1, more preferably 0.

n _{4 is} preferably 0 to 2, more preferably 0 or 1.

n _{5 is} preferably 0 or 1, more preferably 0.

n _{6 is} preferably 0 or 1, more preferably 1.

The preferred one of the cations represented by the above formula (b-5) or formula (b-6), for example, the contents shown below.

Further, an onium salt having a cation represented by the following general formulae (I-2) to (I-5) in the cationic portion can also be used.

In the formulae (I-2) to (I-5), u is an integer of 1 to 3, and 1 or 2 is optimal.

In the formulae (I-2) to (I-4), R ^6a to R ^8a are a stretching alkyl group which may have a substituent or a stretching phenyl group which may have a substituent, and R ^6b to R ^8b are a hydrogen atom and may have a substitution. An alkyl group, a phenyl group or a naphthyl group which may have a substituent.

In the formula (I-5), R ⁹ is an alkyl group which may have a substituent, a phenyl group or a naphthyl group which may have a substituent.

The alkyl group in R ^6a to R ^8a is preferably a linear or branched alkyl group. The carbon number of the alkylene group is preferably from 1 to 12, preferably from 1 to 5, more preferably from 1 to 3, and particularly preferably from 1 or 2.

The substituent which the alkylene group may have is, for example, an alkoxy group, a halogen atom, a hydroxyl group, a keto group (=O), a cyano group, an aryl group, an alkoxyalkyloxy group, an alkoxycarbonylalkyloxy group, C(=O)-OR ^6' , -OC(=O)-R ^7' , -OR ^8', and the like. Alkoxy, halogen atom, aryl, alkoxyalkyloxy, alkoxycarbonylalkyloxy, -C(=O)-OR ^6' , -OC(=O)-R ^7' , -OR ^{8 '} , and in the description of R ^1" to R ^{3" in} the above formula (b-1), the substituents which the substituted aryl group may have are the same.

In the formula, an alkyl group which may have a substituent in R ^6b to R ^8b and R ⁹ is, for example, a substituted alkyl group as exemplified in the description of R ^1" to R ^{3" in} the above formula (b-1). The same content and so on.

The substituent which the phenyl group or the naphthyl group in R ^6b to R ^8b and R ⁹ may have, for example, the substituted aryl group as exemplified in the description of R ^1" to R ^{3" in} the above formula (b-1) The substituents which may be included are the same contents and the like.

The preferred ones of the cations represented by the above formulae (I-2) to (I-5) are, for example, the contents shown below. In the formula, R ^C is a substituent exemplified in the description of the above substituted aryl group (alkoxy group, alkoxyalkyloxy group, alkoxycarbonylalkyloxy group, halogen atom, hydroxyl group, keto group (=O), Aryl, -C(=O)-OR ^6' , -OC(=O)-R ^7' , -OR ^8' ).

The following is a specific illustration.

The anion portion of the cation salt having a cation represented by the formula (I-2) to (I-5) in the cation portion is not particularly limited, and an anion of the currently proposed sulfonium acid generator can be used. The same content. The anion portion is, for example, a fluorinated alkylsulfonic acid ion such as an anion portion (R ^{4 "} SO ₃ ^- ) of the phosphonium salt generator represented by the above formula (b-1) or (b-2); An anion represented by the formula (b-3) or (b-4), an anion represented by any one of the above formulas (b1) to (b9), and the like.

In the present specification, the oxime sulfonate-based acid generator is a compound having at least one group represented by the following formula (B-1), and has characteristics of generating acid by irradiation (exposure) by radiation. . These sulfonate-based acid generators have been widely used in chemically amplified photoresist compositions, and can be arbitrarily selected and used.

[In the formula (B-1), R ³¹ and R ³² each represent an independently-organic group].

The organic group of R ³¹ and R ³² is a group containing a carbon atom, and may have an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (a fluorine atom, a chlorine atom, etc.), etc.) ).

The organic group of R ³¹ is preferably a linear, branched or cyclic alkyl or aryl group. The alkyl group and the aryl group may have a substituent. The substituent is not particularly limited, and examples thereof include a fluorine atom, a linear chain having 1 to 6 carbon atoms, a branched or cyclic alkyl group, and the like. Here, the "having a substituent" means that a part or the whole of a hydrogen atom in an alkyl group or an aryl group is substituted with a substituent.

The alkyl group has a carbon number of 1 to 20, preferably a carbon number of 1 to 10, a carbon number of 1 to 8, preferably a carbon number of 1 to 6, and a carbon number of 1 to 4. good. The alkyl group is particularly preferably an alkyl group which is partially or completely halogenated (hereinafter, also referred to as a halogenated alkyl group). Further, a partially halogenated alkyl group means that an alkyl group in which a part of a hydrogen atom is replaced by a halogen atom is completely represented by a halogenated alkyl group, and an alkyl group in which all hydrogen atoms are replaced by a halogen atom means . The halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, is preferably a fluorine atom. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.

The aryl group preferably has a carbon number of 4 to 20, a carbon number of 4 to 10, and a carbon number of 6 to 10. The aryl group is particularly preferably an aryl group which is partially or completely halogenated. Further, a partially halogenated aryl group means that an aryl group in which a part of a hydrogen atom is replaced by a halogen atom is completely represented by an aryl group which is halogenated, and an aryl group in which all hydrogen atoms are replaced by a halogen atom.

R ^{31 is} particularly preferably an alkyl group having 1 to 4 carbon atoms or a fluorinated alkyl group having 1 to 4 carbon atoms which has no substituent.

The organic group of R ³² is preferably a linear, branched or cyclic alkyl group, an aryl group or a cyano group. The alkyl group and the aryl group of R ^{32 are} , for example, the same as those of the alkyl group and the aryl group exemplified in the above R ³¹ .

R ^{32 is} particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms which has no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

The oxime sulfonate-based acid generator is more preferably, for example, a compound represented by the following formula (B-2) or (B-3).

[In the formula (B-2), R ³³ is a cyano group, an alkyl group having no substituent or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ is an alkyl group or a halogenated alkyl group having no substituent.

[In the formula (B-3), R ³⁶ is a cyano group, an alkyl group having no substituent or a halogenated alkyl group. R ³⁷ is a 2 or 3 valent aromatic hydrocarbon group. R ³⁸ is an alkyl group or a halogenated alkyl group having no substituent. p" is 2 or 3].

In the above formula (B-2), the alkyl group or the halogenated alkyl group having no substituent of R ³³ is preferably a carbon number of 1 to 10, preferably a carbon number of 1 to 8, and a carbon number of 1 to 6. For the best.

R ^{33 is} preferably a halogenated alkyl group or more preferably a fluorinated alkyl group.

The fluorinated alkyl group in R ³³ is preferably one in which the hydrogen atom in the alkyl group is fluorinated by 50% or more, the fluorinated one in 70% or more, and the fluorinated one in 90% or more.

The aryl group of R ³⁴ is, for example, a group obtained by removing one hydrogen atom from a ring of an aromatic hydrocarbon such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group or a phenanthryl group. And a heteroaryl group in which a part of a carbon atom constituting the ring of the group is substituted with a hetero atom such as an oxygen atom, a sulfur atom or a nitrogen atom. Among them, the base is better.

The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group or an alkoxy group. The alkyl group or the halogenated alkyl group in the substituent is preferably a carbon number of 1 to 8, and more preferably a carbon number of 1 to 4. Further, the halogenated alkyl group is preferably a fluorinated alkyl group.

The alkyl group or the halogenated alkyl group having no substituent of R ³⁵ is preferably a carbon number of 1 to 10, preferably a carbon number of 1 to 8, and preferably a carbon number of 1 to 6.

R ^{35 is} preferably a halogenated alkyl group or more preferably a fluorinated alkyl group.

The fluorinated alkyl group in R ³⁵ is preferably one in which the hydrogen atom in the alkyl group is fluorinated by 50% or more, the fluorinated one in 70% or more, and the fluorinated one in 90% or more. The strength of the acid produced is particularly good. The most preferred is a perfluorinated alkyl group in which a hydrogen atom is replaced by 100% fluorine.

In the above formula (B-3), the alkyl group or the halogenated alkyl group having no substituent of R ³⁶ is, for example, the same as the alkyl group or the halogenated alkyl group having no substituent of R ³³ described above.

The 2 or 3 valent aromatic hydrocarbon group of R ³⁷ is, for example, a group obtained by further removing 1 or 2 hydrogen atoms from the aryl group of the above R ³⁴ .

The alkyl group or the halogenated alkyl group having no substituent of R ³⁸ is the same as the alkyl group or the halogenated alkyl group having no substituent of R ³⁵ described above.

p", preferably 2.

Specific examples of the sulfonate-based acid generator include, for example, α-(p-toluenesulfonyloxyimido)-cyanide (cyanide) and α-(p-chlorophenylsulfonyloxyimino). -benzyl cyanide, α-(4-nitrophenylsulfonyloxyimido)-benzyl cyanide, α-(4-nitro-2-trifluoromethylbenzenesulfonyloxyimido)-benzamide Compound, α-(phenylsulfonyloxyimido)-4-chlorobenzyl cyanide, α-(benzene Sulfonoxyimino)-2,4-dichlorobenzyl cyanide, α-(phenylsulfonyloxyimino)-2,6-dichlorobenzyl cyanide, α-(phenylsulfonate) Amino)-4-methoxybenzyl cyanide, α-(2-chlorophenylsulfonyloxyimido)-4-methoxybenzyl cyanide, α-(phenylsulfonyloxyimino)- Thien-2-ylacetonitrile, α-(4-dodecylbenzenesulfonyloxyimino)-benzyl cyanide, α-[(p-toluenesulfonyloxyimino)-4-methoxy Phenyl]acetonitrile, α-[(dodecylbenzenesulfonyloxyimino)-4-methoxyphenyl]acetonitrile, α-(toluenesulfonyloxyimino)-4-thiol Cyanide, α-(methylsulfonyloxyimido)-1-cyclopentenylacetonitrile, α-(methylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(methyl Sulfonoxyimino)-1-cycloheptenylacetonitrile, α-(methylsulfonyloxyimino)-1-cyclooctenylacetonitrile, α-(trifluoromethylsulfonyloxyimino) )-1-cyclopentenylacetonitrile, α-(trifluoromethylsulfonyloxyimido)-cyclohexylacetonitrile, α-(ethylsulfonyloxyimino)-ethylacetonitrile, α-(propyl Alkylsulfonyloxyimido)-propylacetonitrile, α-(cyclohexylsulfonyloxyimino)-cyclopentylacetonitrile, α-(cyclohexylsulfonyloxyimine )-cyclohexylacetonitrile, α-(cyclohexylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(ethylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(n-butylsulfonyloxyimino)-1-cyclopentenylacetonitrile, α-(ethylsulfonate Oxyimido)-1-cyclohexenylacetonitrile, α-(isopropylsulfonyloxyimino)-1-cyclohexenylacetonitrile, α-(n-butylsulfonyloxyimino) 1-cyclohexenylacetonitrile, α-(methylsulfonyloxyimino)-phenylacetonitrile, α-(methylsulfonyloxyimino)-p-methoxyphenylacetonitrile, α- (trifluoromethylsulfonyloxyimino)-phenylacetonitrile, α-(trifluoromethylsulfonyloxyimido)-p-methoxy Phenyl acetonitrile, α-(ethylsulfonyloxyimido)-p-methoxyphenylacetonitrile, α-(propylsulfonyloxyimino)-p-methylphenylacetonitrile, α- (Methylsulfonyloxyimido)-p-bromophenylacetonitrile or the like.

Further, the oxime sulfonate-based acid generator disclosed in JP-A-H09-208554 (paragraphs [0012] to [0014] [Chem. 18] to [Chem. 19], International Publication No. 04/074242 ( The sulfonate-based acid generators disclosed in Examples 1 to 40 of 65 to 86 pages are also suitable for use.

Further, preferred examples are as exemplified below.

Among the diazomethane acid generators, specific examples of the dialkyl or bisarylsulfonyldiazomethanes, for example, bis(isopropylsulfonyl)diazomethane, bis(p-toluenesulfonate) Diazomethane, bis(1,1-dimethylethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(2,4-dimethylphenylsulfonate) Base) diazomethane and the like.

Further, the diazomethane-based acid generator disclosed in Japanese Laid-Open Patent Publication No. Hei 11-035551, No. Hei 11-035552, and No. Hei 11-035573 is also suitably used.

Further, poly(disulfonyl)diazomethane, as disclosed in JP-A-H11-322707, 1,3-bis(phenylsulfonyldiazide) Sulfosyl)propane, 1,4-bis(phenylsulfonyldiazomethylsulfonyl)butane, 1,6-bis(phenylsulfonyldiazomethylsulfonyl)hexane 1,10-bis(phenylsulfonyldiazomethylsulfonyl)decane, 1,2-bis(cyclohexylsulfonyldiazomethylsulfonyl)ethane, 1,3-double (cyclohexylsulfonyldiazomethylsulfonyl)propane, 1,6-bis(cyclohexylsulfonyldiazomethylsulfonyl)hexane, 1,10-bis(cyclohexylsulfonyl) Nitromethylsulfonyl) decane and the like.

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

The component (B) is preferably a sulfonium acid generator containing a fluorinated alkylsulfonic acid ion as an anion.

The content of the component (B) in the photoresist composition of the present invention is preferably 0.5 to 50 parts by mass, more preferably 1 to 40 parts by mass, per 100 parts by mass of the component (A). When it is in the above range, the formation of the pattern can be sufficiently performed. Further, it is preferred to obtain a homogeneous solution, good storage stability, and the like.

<(C) ingredients>

The photoresist composition of the present invention may contain a polymer compound (C) (component (C)) having a structural unit (c0) represented by the following formula (c0).

Wherein R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms; and R ¹ is an alcoholic hydroxyl group having one or more of the first or second order, or a chain of three Alcoholic hydroxyl organic group].

(Structural unit (c0))

In the formula (c0), R is the same as the above.

In the formula (c0), R ¹ is an alcoholic hydroxyl group having one or more of the first or second stages, or a chain-like tertiary alcoholic hydroxyl group.

In the present invention, the alcoholic hydroxyl group means a hydroxyl group bonded to a carbon atom of a chain or cyclic hydrocarbon group.

The "chain-like tertiary alcoholic hydroxyl group" means a hydroxyl group bonded to a tertiary carbon atom constituting a chain hydrocarbon group. The chain hydrocarbon group is, for example, a linear or branched alkyl group as exemplified as R ^{14 in} the structural unit (a1).

Further, the structural unit (c0) may have a primary or secondary alcoholic hydroxyl group, and the hydrocarbon group to which the primary or secondary alcoholic hydroxyl group is bonded may be a chain or a ring. The chain-like or cyclic hydrocarbon group is, for example, a linear or branched alkyl group as recited in R ^{14 of} the structural unit (a1), and an "aliphatic cyclic group" as exemplified in the structural unit (a1).

The organic group of R ¹ is a group having an alcoholic hydroxyl group as described above, that is, it is not particularly limited as long as it has an alcoholic hydroxyl group and a hydrocarbon group bonded to the alcoholic hydroxyl group.

The organic group of R ¹ is specifically, for example, an alkyl group, a divalent aliphatic ring group or a terminal group of a divalent bond group containing a hetero atom bonded to an alcoholic hydroxyl group. An alkyl group, a divalent aliphatic ring group, a divalent bond group containing a hetero atom, an alkylene group and a divalent aliphatic ring in the description of a two-valent bond group of the above Y ² The base and the divalent bond group containing a hetero atom are the same.

The structural unit (c0) is a structural unit represented by the following general formula (c0-11) or (c0-12), a structural unit represented by the following general formula (c0-21) or (c0-22), and The structural unit represented by the general formula (c0-3) is preferred.

The structural unit (c0) having a first-order alcoholic hydroxyl group is preferably a structural unit represented by the following general formula (c0-11) or (c0-12), and has a structural unit (c0) of a secondary alcoholic hydroxyl group, The structural unit represented by the following general formula (c0-21) or (c0-22), or the structural unit represented by the following general formula (c0-12) in the case where the alcohol of the first stage does not have a hydroxyl group is preferable, and has The structural unit (c0) of the chain-like tertiary alcoholic hydroxyl group is preferably a structural unit represented by the following formula (c0-3).

[wherein, R is the same as the above, and Q is an independent single bond, or an alkyl group, a divalent aliphatic ring group or a divalent bond group containing a hetero atom, and A ⁰¹ is A divalent hydrocarbon group having a substituent, and R ⁰ is an independently substituted alkyl group having 1 to 5 carbon atoms. The R ⁰ of the plural in the formula may be the same or different, respectively. P0 is an integer from 0 to 3, p1 is an integer from 1 to 3, and p2 is an integer from 0 to 3.

In the above formula, Q is a single bond, or an alkyl group, a divalent aliphatic ring group or a divalent bond group containing a hetero atom. The alkyl group, the divalent aliphatic ring group, and the divalent bond group containing a hetero atom are the same as those in the above description of the "organic group".

In the above formula, A ⁰¹ is a hydrocarbon group which may have a substituent.

A ⁰¹ in the hydrocarbon group, preferably an aliphatic hydrocarbon group, for example, the description (A) ingredient in the formula (a1-0-2) of the Y ² Y ^{21 is} described in the divalent hydrocarbon group of the divalent aliphatic The hydrocarbon group is the same content and the like.

Among them, the hydrocarbon group in A ⁰¹ is more preferably an alkyl group having 1 to 10 carbon atoms. Further, the alcoholic hydroxyl group bonded to A ⁰¹ is based on a first- or second-order alcoholic hydroxyl group, or a chain-like tertiary alcoholic hydroxyl group, so that the alkyl group of A ⁰¹ is linear or branched. The shape is better.

In the aliphatic hydrocarbon group in A ⁰¹ , a part of a hydrogen atom constituting the aliphatic hydrocarbon group may be substituted with a substituent. a substituent replacing a part of a hydrogen atom, for example, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, a fluorine atom, a fluorinated alkyl group, a hydroxyl group, an oxygen atom (=O), a cyano group, etc., and a hydroxyl group or an alkane The base is good. In the case of having a hydroxyl group as a substituent, the hydroxyl group is preferably a primary or secondary alcoholic hydroxyl group.

In the above formula, R ⁰ is an alkyl group having 1 to 5 carbon atoms, and may be linear or branched, and preferably methyl or ethyl.

In the above formula, p0 is an integer of 0 to 3, preferably 0 to 2, and more preferably 1 to 2. P1 is an integer from 1 to 3, preferably 1 or 2, and more preferably 1. P2 is an integer from 0 to 3, and an integer from 0 to 1 is preferred.

The following is a specific illustration of the structural unit (c0). In the following formulas, R is the same as the above.

In the component (C), the structural unit (c0) may be used singly or in combination of two or more.

In the component (C), the ratio of the structural unit (c0) is not more limited as long as it is 1 mol% or more with respect to the total structural unit constituting the component (C), and may be 100 mol. %. The combination with the structural unit other than the structural unit (c0) is preferably 3 to 95 mol%, preferably 5 to 90 mol%, and more preferably 20 to 85 mol%, and 45 to 45. 75% of the moles is better. When it is more than the lower limit value, the adhesion of the photoresist composition to a support such as a substrate can be improved, and when it is at most the upper limit value, the balance with other structural units can be obtained.

In the present invention, the component (C) is in addition to the above structural unit (c0). It is preferable to further contain a structural unit (c1) containing an acid-decomposable group which increases polarity by an action of an acid. (C) When the composition contains structural unit (c1), the occurrence of scum can be greatly reduced.

The structural unit (c1) is, for example, the same content as the above-described structural unit (a1). Wherein, the structural unit (c1) is preferably the same as the above structural unit (a11), and the structural unit represented by the above formula (a1-1) is preferred, and the above formula (a1-0-11) The structural unit represented by the above is more preferable, and the structural unit represented by the above formula (a1-1-23) is particularly preferable.

In the component (C), the structural unit (c1) may be used singly or in combination of two or more.

Among the components (C), the ratio of the structural unit (c1) is preferably from 1 to 70 mol%, preferably from 3 to 60 mol%, more preferably from 5 to 55 mol%. When it is more than the lower limit value, the occurrence of dross can be greatly reduced, and when it is at most the upper limit value, the balance with other structural units can be obtained, and the adhesion of the photoresist composition to the support such as the substrate can be improved.

The component (C) may contain structural units other than the structural units (c0) and (c1) (hereinafter also referred to as "structural unit (c2)") insofar as the effects of the present invention are not impaired.

The structural unit (c2) is not particularly limited as long as it is another structural unit that is not classified into the structural units (c1) and (c2) described above, and can be used as an ArF excimer laser or KrF A known majority of components for resistive resins such as molecular lasers, EUVs, and EBs.

Structural unit (c2), for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, (meth)acrylic acid 2 -methylpropyl, 1-methylpropyl (meth)acrylate, t-butyl (meth)acrylate, cyclopropyl (meth)acrylate, cyclopentyl (meth)acrylate, (methyl) Cyclohexyl acrylate, 4-methoxycyclohexyl (meth) acrylate, 2-cyclopentyloxycarbonylethyl (meth) acrylate, 2-cyclohexyloxycarbonylethyl (meth) acrylate, (methyl) a chain-like alkyl group such as 2-(4-methoxycyclohexyl)oxycarbonylethyl acrylate, an alkoxy group, or a (meth) acrylate having a monocyclic cycloalkyl group, etc., preferably further The structural unit represented by the formula (c2-1) and the like. In the formula (c2-1), R ⁹⁸ is an alkyl group or alkoxy group having 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, a methoxy group, and an ethoxy group.

[wherein R is the same as described above, and R ⁹⁸ is an alkyl group having 1 to 5 carbon atoms or an alkoxy group].

In the component (C), the structural unit (c2) may be used singly or in combination of two or more.

The proportion of the structural unit (c2) in the component (C) is preferably 0 to 95 mol%, preferably 5 to 90 mol%, more preferably 10 to 50 mol%. When it is above the lower limit value, the lithography etching characteristics can be improved, and the upper limit value is In the next case, the adhesion of the photoresist composition to a support such as a substrate can be improved.

In the present invention, the component (C) is preferably a polymer compound containing a combination of structural units represented by the following formula (C-1). In the following general formula, R, Q, R ²¹ and h are the same as described above, and in the formula, the plural R may be the same or different.

(C) The mass average molecular weight (Mw) of the component (the polystyrene conversion standard of the gel permeation chromatography analyzer) is not particularly limited, and is preferably 20,000 to 500,000, and is 25,000 to 450,000. For better, it is better to use 30,000 to 400,000, and 50,000 to 350,000 is especially good. When the amount is less than or equal to the upper limit of the range, the occurrence of dross can be particularly reduced. When the value is equal to or greater than the lower limit of the range, the adhesion of the photoresist composition to a support such as a substrate can be particularly improved.

Further, the dispersion degree (Mw/Mn) of the component (C) is not particularly limited, and is preferably 1.0 to 5.0, preferably 1.0 to 3.0, and preferably 1.2 to 2.5. Further, Mn represents a number average molecular weight.

The component (C) can be obtained by polymerizing a monomer derived from each structural unit, for example, a radical polymerization initiator such as azobisisobutyronitrile (AIBN) by a known radical polymerization or the like.

The structure of the compound synthesized by a known method can be determined by ¹ H-nuclear magnetic resonance (NMR) spectroscopy, ¹³ C-NMR spectroscopy, ¹⁹ F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass analysis (MS). General organic analysis methods such as method, elemental analysis, and X-ray crystal diffraction are confirmed.

In the photoresist composition of the present invention, the content of the component (C) is less than 25 parts by mass, and preferably 0.05 to 20 parts by mass, and 0.1 to 5 parts by mass, based on 100 parts by mass of the component (A). Preferably, it is more preferably 0.1 to 1 part by mass. When the range is less than or equal to the upper limit, the occurrence of scum can be reduced, and the lithographic etching characteristics can be improved. When the range is at least the lower limit, the adhesion to a support such as a substrate can be improved.

<(D) ingredient>

The photoresist composition of the present invention may contain, as the component (A), the component (B) and the component (C), a photoreactive inhibitor (Quencher) as the component (D).

The "inhibitor" is an acid which is an acid diffusion controlling agent, that is, an acid produced by the above-mentioned (B) component by exposure.

The "photoreactive inhibitor" has an action as an inhibitor before exposure (or in an unexposed portion), and does not have an inhibitor function after exposure (irradiation by radiation such as EB or EUV).

As the component (D), a component known as a photoreactive inhibitor, for example, a basic compound formed of a cationic moiety and an anion moiety, or the like can be used. The basic compound can capture the aforementioned (B) component by alkali exchange The acid produced (strong acid).

Further, the "basic compound" in the present invention means a compound which is relatively basic with respect to the acid produced by the component (B).

(D) component, more specifically, for example, the compound (D1) represented by the following formula (d1) (hereinafter, also referred to as (D1) component), or the compound represented by the following formula (d2) (D2) (hereinafter, also referred to as (D2) component), the compound (D3) represented by the following formula (d3) (hereinafter, also referred to as (D3) component).

Wherein R ³ is a hydrocarbon group which may have a substituent, and Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (however, S is a carbon atom which is not substituted by a fluorine atom), and R ⁴ is The organic group, Y ³ is a linear, branched or cyclic alkyl or aryl group, Rf ₀ is a hydrocarbon group, and Z ⁺ is a separate ruthenium or osmium cation.

[(D1) ingredients] ‧ anion

In the formula (d1), R ³ is a hydrocarbon group which may have a substituent.

The hydrocarbon group which may have a substituent of R ³ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be the same as the aliphatic hydrocarbon group or the aromatic hydrocarbon group of X ^{3 in} the component (B).

Wherein R ³ may have a hydrocarbon group of a substituent, and may be an aromatic hydrocarbon group which may have a substituent, or an aliphatic ring group which may have a substituent, preferably a phenyl group or a naphthyl group which may have a substituent; More preferably, a group obtained by removing one or more hydrogen atoms from a polycyclic alkane such as adamantane, norbornane, isodecane, tricyclodecane or tetracyclododecane is more preferable.

Further, a hydrocarbon group which may have a substituent of R ³ may be a linear, branched or alicyclic alkyl group, or a fluorinated alkyl group is also preferred.

The carbon number of the linear, branched or alicyclic alkyl group of R ³ is preferably from 1 to 10, specifically, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group or a hexyl group. a linear alkyl group such as heptyl, octyl, decyl or decyl, 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methyl Butyl, 3-methylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl An alicyclic alkyl group such as a branched alkyl group, a thiol group or an adamantyl group.

The fluorinated alkyl group of R ³ may be in the form of a chain or a ring, and is preferably a linear or branched chain.

The carbon number of the fluorinated alkyl group is preferably from 1 to 11, more preferably from 1 to 8, and more preferably from 1 to 4. Specifically, for example, a hydrogen atom constituting a part or all of a linear alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group or a fluorenyl group. a group substituted by a fluorine atom, or a composition of 1-methylethyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl A group in which a part or all of a hydrogen atom of a branched alkyl group is substituted by a fluorine atom or the like.

Further, the fluorinated alkyl group of R ³ may contain an atom other than a fluorine atom. An atom other than a fluorine atom, for example, an oxygen atom, a carbon atom, a hydrogen atom, an oxygen atom, a sulfur atom, a nitrogen atom or the like.

Wherein, the fluorinated alkyl group of R ³ is preferably a group in which a part or all of a hydrogen atom constituting one of the linear alkyl groups is substituted by a fluorine atom, so that all hydrogen atoms constituting the linear alkyl group are fluorine-containing. The group substituted by an atom (perfluoroalkyl group) is preferred.

The following is a preferred specific example of the anion portion of the component (D1).

‧Catalyst

In the formula (d1), Z ⁺ is a ruthenium or osmium cation.

The ruthenium or ruthenium cation of Z ⁺ is not particularly limited, and for example, it may be the same as the cation of the above formula (b-1) or (b-2).

The component (D1) may be used singly or in combination of two or more.

[(D2) ingredients] ‧ anion

In the formula (d2), Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent.

Z ^2c may have a hydrocarbon group having 1 to 30 carbon atoms, may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be, for example, the same as the aliphatic hydrocarbon group or aromatic hydrocarbon group of X ^{3 in} the component (B). The content and so on.

Wherein, the hydrocarbon group which may have a substituent of Z ^2c is preferably an aliphatic cyclic group which may have a substituent, and is adamantane, norbornane, isodecane, tricyclodecane, tetracyclododecane More preferably, the base (which may have a substituent) obtained by removing one or more hydrogen atoms from camphor alkane is preferable.

The hydrocarbon group of Z ^2c may have a substituent, and the substituent is, for example, the same as X ³ in the component (B). However, in Z ^2c , the carbon adjacent to the S atom in SO ₃ ^- is not replaced by fluorine. When the SO ₃ ^- is not adjacent to the fluorine atom, the anion of the (d2) component forms a suitable weak acid anion, and the ability to suppress the (D) component can be improved.

The following is a preferred specific example of the anion portion of the component (d2).

‧Catalyst

In the formula (d2), Z ⁺ is the same as Z ⁺ in the above formula (d1).

The component (D2) may be used singly or in combination of two or more.

[(D3) ingredients] ‧ anion

In the formula (d3), R ⁴ is an organic group.

The organic group of R ⁴ is not particularly limited, and for example, an alkyl group, an alkoxy group, -OC(=O)-C(R ^C2 )=CH ₂ (R ^C2 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms a group or a halogenated alkyl group having 1 to 5 carbon atoms, or -OC(=O)-R ^C3 (R ^C3 is a hydrocarbon group).

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

The alkoxy group of R ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms and an alkoxy group having 1 to 5 carbon atoms, specifically, for example, a methoxy group, an ethoxy group, an n-propoxy group, or the like. -propoxy, n-butoxy, tert-butoxy and the like. Among them, methoxy and ethoxy groups are preferred.

When R ⁴ is -OC(=O)-C(R ^C2 )=CH ₂ , R ^C2 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms.

The alkyl group having 1 to 5 carbon atoms in R ^C2 is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, specifically, for example, methyl group, ethyl group, propyl group or isopropyl group. Base, n-butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, and the like.

The halogenated alkyl group in R ^C2 is, for example, a group in which a part or all of a hydrogen atom in the alkyl group having 1 to 5 carbon atoms is substituted by a halogen atom. The halogen atom is, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or the like, and particularly preferably a fluorine atom.

R ^C2, hydrogen atoms, or alkyl having 1 to 3 carbon atoms of the fluorinated alkyl group preferably having 1 to 3, it is easy to obtain and the like of the industrial viewpoints, the hydrogen atom or a methyl groups.

In the case where R ⁴ is -OC(=O)-R ^C3 , R ^C3 is a hydrocarbon group.

The hydrocarbon group of R ^C3 may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The hydrocarbon group of R ^C3 is, for example, the same as the hydrocarbon group of X ^{3 in} the component (B).

Wherein, the hydrocarbon group of R ^{C3 further} removes one or more hydrogen atoms by a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isodecane, tricyclodecane or tetracyclododecane. The obtained alicyclic group or an aromatic group such as a phenyl group or a naphthyl group is preferred. In the case where R ^C3 is an alicyclic group, the photoresist composition can be well dissolved in an organic solvent with good lithographic etching characteristics. Further, in the case where R ^C3 is an aromatic group, in the lithography etching using EUV or the like as an exposure light source, the photoresist composition has excellent light absorption efficiency and has good sensitivity or lithographic etching characteristics.

Wherein R ^{4 is} again -OC(=O)-C(R ^C2' )=CH ₂ (R ^C2' is a hydrogen atom or a methyl group), or, -OC(=O)-R ^C3' (R ^C3' It is preferably an aliphatic cyclic group).

In the formula (d3), Y ³ is a linear, branched or cyclic alkyl group or an extended aryl group.

a linear, branched or cyclic alkyl or aryl group of Y ³ and a linear chain of Y ² of the above formula (a1-0-2), "linear" The branched aliphatic hydrocarbon group, the "cyclic aliphatic hydrocarbon group", and the "aromatic hydrocarbon group" are the same contents.

Among them, Y ^{3 is} preferably an alkylene group, and a linear or branched alkyl group is preferred, and a methyl group or an ethyl group is more preferred.

In the formula (d3), Rf ₀ is a hydrocarbon group containing a fluorine atom.

The hydrocarbon group containing a fluorine atom of Rf ₀ is preferably a fluorinated alkyl group, and more preferably the same as the above-mentioned fluorinated alkyl group of R ³ .

The following is a preferred specific example of the anion portion of the component (D3).

‧Catalyst

In the formula (d3), Z ⁺ is the same as Z ⁺ in the above formula (d1).

The component (D3) may be used singly or in combination of two or more.

The component (D) may be any one of the above (D1) to (D3) components, and may be contained in combination of two or more.

The total content of the components (D1) to (D3) is preferably 0.5 to 10.0 parts by mass, and 0.5 to 8.0 by mass based on 100 parts by mass of the component (A). The portion is preferably used, and more preferably 1.0 to 5.0 parts by mass. When the value is at least the lower limit of the above range, in particular, good lithographic etching characteristics and a resist pattern shape can be obtained. When it is below the upper limit of the above range, it can maintain good sensitivity and also has excellent yield.

{(D) ingredient manufacturing method}

The method for producing the component (D1) and the component (D2) in the present invention is not particularly limited, and it can be produced by a known method.

Further, the method for producing the component (D3) is not particularly limited. For example, R ⁴ in the above formula (d3) is a case where the terminal of the Y ³ bond has a group of an oxygen atom, and the following formula can be used. The compound (i-1) represented by the formula (i-1) is reacted with the compound (i-2) represented by the following formula (i-2) to obtain the following formula (i-3). The compound (i-3) is represented by reacting the compound (i-3) with A ^- Z ⁺ (i-4) having the desired cation Z ⁺ to obtain the formula (d3). The compound (D3) is indicated.

^{[Wherein, R 4, Y 3, Rf} 0, Z +, respectively, with the general formula (d3) of the _{^{R 4, Y 3, Rf 0}} , Z + is the same. R ^4a is a group obtained by removing an oxygen atom at the terminal from R ⁴ , and A ^- is a pair of anions].

First, the compound (i-1) is reacted with the compound (i-2) to obtain a compound (i-3).

In the formula (i-1), R ⁴ is the same as the above, and R ^4a is a group obtained by removing the oxygen atom at the terminal end from the above R ⁴ . In the formula (i-2), Y ³ and Rf ₀ are the same as those described above.

The compound (i-1) and the compound (i-2) may be used commercially or in combination.

The compound (i-1) is reacted with the compound (i-2) to produce the compound (i-3), which is not particularly limited, for example, as appropriate In the presence of an acid catalyst, the compound (i-2) and the compound (i-1) are reacted in an organic solvent, and then the reaction mixture is washed and recovered.

The acid catalyst in the above reaction is not particularly limited, and for example, toluenesulfonic acid or the like is used in an amount of about 0.05 to 5 moles per mole of the compound (i-2).

The organic solvent in the above reaction may be an organic solvent which can dissolve the compound (i-1) and the compound (i-2) as a raw material, specifically, for example, toluene or the like, which is used in an amount relative to the compound (i) -1), preferably 0.5 to 100 parts by mass, more preferably 0.5 to 20 parts by mass. The solvent may be used singly or in combination of two or more.

The amount of the compound (i-2) to be used in the above reaction is usually preferably from 0.5 to 5 mols, more preferably from about 0.8 to 4 mols, per mol of the compound (i-1).

The reaction time in the above reaction varies depending on the reactivity of the compound (i-1) and the compound (i-2), or the reaction temperature, etc., and usually, it is preferably 1 to 80 hours, and 3 to 60 hours. For better.

The reaction temperature in the above reaction is preferably from 20 ° C to 200 ° C, more preferably from about 20 ° C to 150 ° C.

Subsequently, the obtained compound (i-3) is reacted with the compound (i-4) to give a compound (d1-3).

In the formula (i-4), Z ⁺ is the same as the above, and A ^- is a counter anion.

The compound (i-3) is reacted with the compound (i-4) to obtain The method of the compound (D3) is not particularly limited. For example, the compound (i-3) is dissolved in a suitable organic solvent and water in the presence of a suitable alkali metal hydroxide, and a compound is added ( I-4) It is carried out by stirring and reacting it.

The alkali metal hydroxide in the above reaction is not particularly limited, and is, for example, sodium hydroxide, potassium hydroxide or the like, and is used in an amount of about 0.3 to 3 mol per mol of the compound (i-3). It is better.

The organic solvent in the above reaction, for example, a solvent such as dichloromethane, chloroform or ethyl acetate, is preferably used in an amount of 0.5 to 100 parts by mass, more preferably 0.5 to 20 parts by mass, based on the compound (i-3). good. The solvent may be used singly or in combination of two or more.

The amount of the compound (i-4) to be used in the above reaction is usually preferably from 0.5 to 5 mols, more preferably from about 0.8 to 4 mols, per mol of the compound (i-3).

The reaction time in the above reaction is different depending on the reactivity of the compound (i-3) and the compound (i-4), or the reaction temperature, etc., and usually, it is preferably 1 to 80 hours, and 3 to 60 hours is used. Better.

The reaction temperature in the above reaction is preferably from 20 ° C to 200 ° C, more preferably from about 20 ° C to 150 ° C.

After completion of the reaction, the compound (D3) in the reaction mixture may be isolated and purified. For the method of separation and purification, a conventionally known method can be used. For example, any one of concentration, solvent extraction, distillation, crystallization, recrystallization, and chromatography can be used alone, or two or more of them can be used in combination. can.

The structure of the compound (D3) obtained by the above method can be determined by ¹ H-nuclear magnetic resonance (NMR) spectroscopy, ¹³ C-NMR spectroscopy, ¹⁹ F-NMR spectroscopy, infrared absorption (IR) spectroscopy, mass analysis. General organic analysis methods such as (MS) method, elemental analysis method, and X-ray crystal diffraction method are confirmed.

<arbitrary ingredients> [(D’) ingredients]

The photoresist composition of the present invention may contain a basic compound component (D') which is not equivalent to the above component (D) (hereinafter, also referred to as "(D') component" as long as the effect of the present invention is not impaired. ) as an optional ingredient. The component (D') has the same function as the above-mentioned component (D), and has an action of trapping an acid (Quencher) which is exposed to the acid produced by the component (B).

The component (D') is a member which is relatively basic to the component (B) and has an action as an acid diffusion controlling agent, and is not particularly limited as long as it does not correspond to the component (D). Any of the known ingredients can be used arbitrarily. For example, an amine such as an aliphatic amine or an aromatic amine is preferably an aliphatic amine, particularly a secondary aliphatic amine or a tertiary aliphatic amine.

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

The aliphatic amine refers to an amine (alkylamine or alkanolamine) or a cyclic amine which is substituted with at least one of hydrogen atoms of ammonia NH ₃ and substituted with an alkyl group having 12 or less carbon atoms or a hydroxyalkyl group.

Specific examples of the alkylamine and the alkanolamine, such as n-hexylamine, n-heptylamine, n-octylamine, n-decylamine, n-decylamine and the like, monoalkylamine; diethylamine, di-n-propylamine, a dialkylamine such as di-n-heptylamine, di-n-octylamine or dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, a trialkylamine such as tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-decylamine, tri-n-decylamine or tri-n-dodecylamine; diethanolamine An alkanolamine such as triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine or tri-n-octanolamine. Among them, a trialkylamine having 5 to 10 carbon atoms is more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

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

The aliphatic monocyclic amine is specifically, for example, piperidine, hexahydropyrazine or the like.

Aliphatic polycyclic amines preferably having a carbon number of 6 to 10, specifically 1,5-diazabicyclo[4.3.0]-5-decene, 1,8-diaza Ring [5.4.0]-7-undecene, hexamethylenetetramine, 1,4-diazabicyclo[2.2.2]octane, and the like.

Other aliphatic amines, for example, tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxy Ethylethoxymethoxy)ethyl}amine, tris{2-(1-methoxyethoxy)ethyl}amine, tris{2-(1-ethoxyethoxy)ethyl}amine , three {2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-(2-hydroxyethoxy)ethoxy}ethyl] Amine, triethanolamine triacetate, etc., and triethanolamine triacetate are preferred.

Aromatic amines, for example, aniline, pyridine, 4-dimethylaminopyridine, pyrrole, hydrazine, pyrazole, imidazole or such derivatives, diphenylamine, triphenylamine, tribenzylamine, 2,6-diisopropyl Aniline, N-tert-butoxycarbonylpyrrolidine, and the like.

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

The component (D') is usually in the range of 0.01 to 5.0 parts by mass based on 100 parts by mass of the component (A). When it is in the above range, the shape of the resist pattern, the stability over time of storage, and the like can be improved.

[(E) ingredients]

The photoresist composition may contain a group of organic carboxylic acids and phosphorus oxyacids and derivatives thereof for the purpose of preventing sensitivity deterioration, improving the shape of the photoresist pattern, and the stability over time of storage. At least one compound (E) (hereinafter also referred to as "(E) component)) is selected.

The organic carboxylic acid is preferably, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid or the like.

Phosphorus oxyacids, for example, phosphoric acid, phosphonic acid, phosphinic acid, etc., and among these, phosphonic acid is particularly preferred.

The derivative of the oxyacid of phosphorus, for example, an ester in which the hydrogen atom of the oxyacid is substituted with a hydrocarbon group, and the hydrocarbon group is, for example, an alkyl group having 1 to 5 carbon atoms or an aryl group having 6 to 15 carbon atoms.

Derivatives of phosphoric acid, for example, di-n-butyl phosphate, diphenyl phosphate, etc. Phosphate esters, etc.

A derivative of a phosphonic acid, for example, a phosphonate such as dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate or dibenzyl phosphonate.

A derivative of phosphinic acid, for example, a phosphinate such as phenylphosphinic acid.

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

(E) Ingredients, organic carboxylic acids are preferred, and salicylic acid is preferred.

The component (E) is used in an amount of 0.01 to 5.0 parts by mass based on 100 parts by mass of the component (A).

In the photoresist composition of the present invention, a surfactant containing a mixture of additives such as a resin added to improve the performance of the photoresist film and a coating property for improving the coating property may be appropriately added in combination with the intended purpose. , dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like.

[(S) ingredients]

The photoresist composition can be produced by dissolving a component added to the photoresist composition in an organic solvent (hereinafter also referred to as "(S) component").

The (S) component is not particularly limited as long as it can dissolve the components to be used, and a suitable solution can be used as the solvent of the conventional chemically amplified resist, and one or two or more of them can be appropriately selected. Ingredients.

(S) components, for example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-hexanone, methyl isohexanone, and 2-heptanone Polyols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol; ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate a compound having an ester bond, a polyalkylene or a monoalkyl ether such as monoethyl ether, monoethyl ether, monopropyl ether or monobutyl ether or a monophenyl ether having the above ester-bonded compound a derivative of a polyol such as an ether-bonded compound [in which propylene glycol monomethyl ether acetate (PGMEA) or propylene glycol monomethyl ether (PGME) is preferred]; a cyclic ether such as dioxane , or methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxy propionate Ester, anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenethyl ether, butyl phenyl ether, ethyl benzene, diethyl benzene, pentyl benzene, isopropyl An aromatic organic solvent such as benzene, toluene, xylene, cumene or trimethylbenzene.

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

Among them, γ-butyrolactone, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and ethyl lactate (EL) are preferred.

Further, a mixed solvent obtained by mixing PGMEA with a polar solvent is also preferable. The addition ratio (mass ratio) can be appropriately determined after considering the compatibility of PGMEA with a polar solvent, and preferably in the range of 1:9 to 9:1, and 2:8 to 8:2. The range is better.

More specifically, in the case of adding EL as a polar solvent, the mass ratio of PGMEA:EL is preferably 1:9 to 9:1, more preferably 2:8. ~8:2. Further, in the case of adding PGME as a polar solvent, the mass ratio of PGMEA:PGME is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, still more preferably 3:7 to 7:3. .

Further, as the (S) component, for example, a mixed solvent obtained by at least one selected from PGMEA and EL and γ-butyrolactone may be preferably used. In this case, the mixing ratio is preferably 70:30 to 95:5 in terms of the mass ratio of the former to the latter.

Further, the (S) component may be, for example, a mixed solvent of PGMEA and cyclohexanone, or a mixed solvent of PGMEA and PGME and cyclohexanone. In this case, the mixing ratio of the former is preferably, the mass ratio is PGMEA: cyclohexanone = 95 to 5: 10 to 90, and the mixing ratio of the latter is preferred, and the mass ratio is PGMEA: PGME: ring. Hexanone = 35~55:25~45:10~30.

According to the present invention, it is possible to obtain a photoresist composition which can improve the adhesion to the support such as a substrate and the lithographic etching property, and reduce the occurrence of scum.

The reason why the above effects can be obtained is still unclear, but it is presumed that the structural unit (c0) having a primary or secondary alcoholic hydroxyl group or a chain-like tertiary alcoholic hydroxyl group can be used as a polar group. The hydroxyl group is strongly bonded to a support such as a substrate, and the photoresist composition is less likely to be peeled off by the developer or the like (lifting adhesion). Further, when the adhesion is improved, the occurrence of scum due to the peeled photoresist composition can be reduced, and the lithographic etching characteristics can be improved.

Further, since the photoresist composition of the present invention contains the component (D), the acid can be diffused to the unexposed portion, and in the exposed portion, Since the component (D) loses its ability to suppress, the contrast of the acid concentration between the exposed portion and the unexposed portion can be increased, and the lithographic etching property or the pattern shape can be further improved. Moreover, it is expected that the increase in contrast is also expected to reduce the occurrence of scum.

How to form a photoresist pattern?

The photoresist pattern can be formed by using the above-described photoresist composition, for example, according to the formation method of the photoresist pattern below.

First, the photoresist composition is applied onto a support using a spin coater or the like, and subjected to pre-baking at a temperature of 80 to 150 ° C for 40 to 120 seconds, preferably 60 to 90 seconds. (Post Apply Bake (PAB)), for example, using an electron beam drawing machine, etc., selectively exposing the electron beam (EB) to the desired mask pattern, and then operating at 80 to 150 ° C. Apply PEB (heating after exposure) for 40 to 120 seconds, preferably 60 to 90 seconds. Subsequently, it is subjected to development processing.

In the case of the alkali developing process, an alkali developing solution, for example, an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH) is used for alkali development treatment.

Further, in the case of the solvent developing process, development treatment is carried out using an organic solvent. The organic solvent is not particularly limited as long as it can dissolve the component (A) (component (A) before exposure), and can be appropriately selected from known organic solvents. Specifically, for example, a ketone solvent, an ester solvent, an alcohol solvent, a guanamine solvent, a polar solvent such as an ether solvent, a hydrocarbon solvent, or the like, and an ester solvent is preferable. The ester solvent is preferably butyl acetate. As described above, the photoresist composition of the present invention is formed in a contact hole pattern In the case of a negative resist composition for a solvent developing process which is repeatedly used, the contact hole pattern can be effectively prevented from forming an inverse pyramid shape, and therefore it is preferably used in a solvent developing process.

After the development treatment, it is preferred to carry out a washing treatment. In the case of the alkali development process, it is preferred to use pure water for water washing. In the case of the solvent developing process, it is preferred to use the organic solvent described above as the washing liquid.

It is then dried. Further, depending on the case, the baking treatment may be performed after the above development treatment (post-baking; PostBake). In this way, a photoresist pattern that is faithful to the mask pattern can be produced.

The support is not particularly limited, and a conventionally known one can be used, for example, a substrate for an electronic component, or a person who forms a specific wiring pattern thereon. More specifically, for example, a substrate made of a metal such as germanium wafer, copper, chromium, iron, or aluminum, or a glass substrate. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold, or the like can be used. Moreover, when the photoresist composition of the present invention is used, even on a stepped substrate having a high step of about several tens to several hundreds of nm, excellent lithographic etching characteristics and adhesion can be formed without scumming. The pattern can also be used on a stepped substrate as a substrate.

Further, the support may be provided with an inorganic or/or organic film on the substrate. An inorganic film, for example, an inorganic antireflection film (inorganic BARC) or the like. Organic film, for example, organic anti-reflective film (organic BARC).

The wavelength used for the exposure is not particularly limited, and an ArF excimer laser, a KrF excimer laser, an F2 excimer laser, an EUV (very ultraviolet ray), a VUV (vacuum ultraviolet ray), an EB (electron line) can be used. ), X Radiation lines such as lines and soft X lines are used.

The photoresist composition of the present invention is more effective for KrF excimer lasers, ArF excimer lasers, EB or EUV, and is particularly effective for ArF excimer lasers.

The exposure of the photoresist film may be a normal exposure (dry exposure) or an immersion exposure in an inert gas such as air or nitrogen.

Infiltrating exposure refers to a portion of a lens that is filled with an inert gas such as air or nitrogen and a photoresist film on a wafer during exposure, and is filled with a solvent having a refractive index higher than that of air (infiltration medium). Exposure is performed in the state of ).

More specifically, the immersion exposure is such that, between the photoresist film obtained in the above manner and the lens at the lowest position of the exposure device, a solvent (infiltration medium) having a refractive index greater than that of air is filled. In this state, exposure (immersion exposure) is performed by the desired mask pattern.

The immersion medium is preferably a solvent having a refractive index larger than that of air and having a refractive index smaller than that of the resist film exposed by the immersion exposure. The refractive index of the solvent is not particularly limited as long as it is within the above range.

A solvent having a refractive index larger than that of air and having a refractive index smaller than that of the photoresist film, for example, water, a fluorine-based inert liquid, an oxime-based solvent, a hydrocarbon-based solvent, or the like.

Specific examples of the fluorine-based inert liquid include, for example, a liquid containing a fluorine-based compound such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ or C ₅ H ₃ F ₇ as a main component. It is better to have a boiling point of 70 to 180 ° C, and preferably 80 to 160 ° C. When the fluorine-based inert liquid is a liquid having a boiling point within the above range, it is more preferable to remove the medium used for the wetting in a simple manner after the completion of the exposure.

The fluorine-based inert liquid is particularly preferably a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are replaced by fluorine atoms. Specific examples of the perfluoroalkyl group include a perfluoroalkyl ether compound or a perfluoroalkylamine compound.

More specifically, the perfluoroalkyl ether compound may, for example, be perfluoro(2-butyl-tetrahydrofuran) (boiling point: 102 ° C), and the perfluoroalkylamine compound may be, for example, perfluorotributylamine (boiling point: 174 ° C). .

Infiltration of the medium, in terms of cost, safety, environmental issues, and versatility, it is preferred to use water.

[Examples]

In the following, the invention will be described in more detail by way of examples, but the invention is not limited by the examples.

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

The components shown in Table 1 were mixed and dissolved to prepare a positive photoresist composition.

Each of the abbreviations in Table 1 has the following meanings. Further, the value in [ ] is the added amount (parts by mass).

(A)-1: The following polymer compound (A)-1 [l/m/n = 40/40/20 (mole ratio), Mw = 8000, Mw/Mn = 1.67].

(B)-1: The following compound (B)-1.

(B)-2: The following compound (B)-2.

(C)-1: The following polymer compound (C)-0 [l/m = 60/40 (mole ratio), Mw = 100,000, Mw/Mn = 242].

(D)-1: The following compound (D)-1.

(D)-2: The following compound (D)-2.

(D)-3: The following compound (D)-3.

(D')-4: Tri-n-pentylamine.

(E)-1: Salicylic acid.

(S)-1: a mixed solvent of PGMEA/PGME=60/40 (mass ratio).

[Formation of photoresist pattern 1]

The photoresist composition was applied onto a 8-inch substrate using a spin coater, and subjected to pre-baking (PAB) treatment on a hot plate at 130 ° C for 60 seconds to form a film thickness. 240 nm photoresist film.

Next, an ArF exposure apparatus NSR-S308F (manufactured by Nikon Corporation; NA (number of openings) = 0.80, σ = 0.85) was used for the above-mentioned photoresist film, and an ArF excimer laser (193 nm) was selected through a mask pattern. Sexual photo Shoot. Subsequently, post-exposure heating (PEB) treatment was carried out at 110 ° C for 60 seconds, and at 23 ° C, 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) was used. NMD-3 (Tokyo Yinghua Industrial Co., Ltd.) The company was developed under the conditions of 30 seconds, and then washed with pure water for 30 seconds, vibrated and dried, and then baked at 100 ° C for 45 seconds.

As a result, in Examples 1 to 3 and Comparative Example 1, a 1:1 line and a space (LS) pattern having a line width of 160 nm and a pitch of 320 nm (having good adhesion) were formed on the photoresist film. On the other hand, in Comparative Example 2, the photoresist film was peeled off from the substrate during development, and the pattern was not formed (adhesion deteriorated). The results are shown in Table 2 as "adhesiveness".

Further, after the treatment with hexamethyldioxane (HMDS) at 110 ° C for 25 seconds, the formation of the LS pattern was carried out according to the same operation as the pattern formation, and the formation of the above-mentioned line width of 161 nm was 1:1. In the optimum exposure amount at the time of the LS pattern, a 1:1 LS pattern having a line width of 140 nm and a pitch of 280 nm was formed. As a result, in Examples 1 to 3, a 1:1 LS pattern having a line width of 140 nm was formed, and on the other hand, Comparative Example 1 failed to form a pattern. The results are shown in Table 2 as "analytical".

From the results of Table 2, it was found that the photoresist compositions of Examples 1 to 3 had good adhesion when compared with the photoresist composition of Comparative Example 2. Therefore, a photoresist pattern can be formed. Further, when the photoresist compositions of Examples 1 to 3 were compared with the photoresist composition of Comparative Example 1, it was confirmed that the photoresist etching characteristics such as excellent resolution were obtained.

[Example 4, Comparative Example 3]

The components shown in Table 3 were mixed and dissolved to prepare a positive photoresist composition.

In each of the abbreviations in Table 3, (B)-2, (C)-1, (D)-1, (D')-4, (E)-1, (S)-1 are the same as the above. content. Further, the value in [ ] is the added amount (parts by mass).

(A)-2: l/m/n/o=5/40/40/15 (mole ratio), Mw=5000, Mw/Mn=1.69, the following polymer compound (A)-0.

(B)-3: The following compound (B)-3.

[Formation of photoresist pattern 2]

The photoresist compositions were applied to a 8-inch step substrate treated with hexamethyldioxane (HMDS) at 90 ° C for 36 seconds using a spin coater, and compared on a hot plate. In Example 3, prebaking (PAB) treatment was carried out at 130 ° C in Example 4 at 140 ° C for 60 seconds, and as a result of drying, a photoresist film having a film thickness of 333 nm was formed. The step substrate is a substrate having a line-shaped step pattern (high step: 300 nm) having a line width of 160 nm and a pitch of 320 nm on the surface of the substrate.

Next, an ArF exposure apparatus NSR-S308F (manufactured by Nikon Corporation; NA (number of openings) = 0.75, σ = 0.60) was used, and an ArF excimer laser (193 nm) was used to have a line pattern and a mask pattern having a step difference. The mask pattern of the vertical cross configuration selectively irradiates the photoresist film. Subsequently, post-exposure heating (PEB) treatment was performed at 115 ° C for 60 seconds. Further, at 23 ° C, development was carried out for 30 seconds using a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) in NMD-3 (manufactured by Tokyo Ohka Kogyo Co., Ltd.), followed by 30 seconds. The mixture was washed with water using pure water, vibrated and dried, and then baked at 100 ° C for 45 seconds.

As a result, in any of the examples, the photoresist film was formed with a 1:1 line and space (LS) pattern having a line width of 200 nm and a pitch of 400 nm (having good adhesion).

[Evaluation of development defects]

The surface development defect of the photograph was visually observed by using a length measuring SEM (manufactured by Hitachi, Ltd., product name: S-9220) on a 1:1 LS pattern of 350 nm obtained by the above method. The evaluation was carried out on the basis of the following criteria, and the results are shown in Table 2.

◎: No development defects were observed by visual observation.

×: Development defects were observed by visual observation.

As is apparent from the results of Table 4, when the photoresist composition of Example 4 was compared with the photoresist composition of Comparative Example 3, it was confirmed that there were few development defects.

[Example 5, Comparative Example 4]

The components shown in Table 5 were mixed and dissolved to prepare a positive photoresist composition.

In each of the abbreviations in Table 5, (C)-1, (D)-1, (E)-1, and (S)-1 are the same as the above, and the others have the following meanings. Further, the value in [ ] is the added amount (parts by mass).

(B)-4: The following compound (B)-4.

(A)-3: The above polymer compound (A)-0 having l/m/n/o=5/40/40/15 (mole ratio), Mw=14000, and Mw/Mn=170.

(D')-5: 2,6-diisopropylaniline.

[Formation of photoresist pattern 3]

The photoresist compositions were applied to an 8-inch substrate treated with hexamethyldioxane (HMDS) at 90 ° C for 36 seconds using a spin coater, and placed on a hot plate at 140 ° C. The pre-baking (PAB) treatment was carried out for 60 seconds, and as a result of drying, a thick film photoresist film having a film thickness of 900 nm was formed.

Next, using the ArF exposure apparatus NSR-S308F (manufactured by Nikon Corporation; NA (number of openings) = 0.75, σ = 0.95), the resist film was selectively irradiated with a mask pattern by an ArF excimer laser. Subsequently, Example 5 was subjected to post-exposure heating (PEB) treatment at 125 ° C, Comparative Example 4 at 120 ° C for 60 seconds, and at 23 ° C, using 2.38 mass % tetramethylammonium hydroxide (TMAH). )Aqueous solution NMD-3 (Tokyo Chemical The product was developed under the conditions of 30 seconds, and then washed with water using pure water for 30 seconds, vibrated and dried, and then baked at 100 ° C for 45 seconds.

As a result, it was found that the 1:1 line and space (LS) pattern (having good adhesion) having a line width of 300 nm and a pitch of 600 nm was formed on any of the photoresist films in any of the examples. The results of the adhesion are shown in Table 6.

[Micro-etching characteristics evaluation]

The 300 nm 1:1 LS photoresist pattern obtained by the above method was observed using a length measuring SEM (manufactured by Hitachi, Ltd., product name: S-9220), and it was confirmed that the pattern was partially peeled off or the shape of the line was generated. . The evaluation results based on the following benchmarks are shown in Table 6.

◎: Highly rectangular shape and excellent pattern shape.

×: Head shape, the shape of the figure is inferior.

As is apparent from the results of Table 6, when the photoresist composition of Example 5 was compared with the photoresist composition of Comparative Example 4, it was confirmed that it had excellent lithographic etching characteristics.

Claims (5)

A photoresist composition comprising a substrate component (A) which changes solubility in a developing solution by an action of an acid, an acid generator component (B) which generates an acid by exposure, and has the following The polymer compound (C) of the structural unit (c0) represented by the formula (c0), and the compound (D1) represented by the following formula (d1) and the compound represented by the following formula (d2) ( a photoreactive inhibitor (D) of one or more selected from the group consisting of the compound (D3) represented by the following formula (d3), [wherein, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms, and R ¹ is an alcoholic hydroxyl group having one or more of the first or second order, or a chain of three Alcoholic hydroxyl organic group] Wherein R ³ is a hydrocarbon group which may have a substituent, and Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent, but S is an adjacent carbon which is not substituted by a fluorine atom, and R ⁴ is an organic group. Further, Y ³ is a linear, branched or cyclic alkyl or aryl group, Rf ₀ is a hydrocarbon group, and Z ⁺ is a separate ruthenium or osmium cation. The photo-resist composition of claim 1, wherein the polymer compound (C) further has a structural unit (c1) containing an acid-decomposable group which increases polarity by an action of an acid. The photoresist composition according to claim 1 or 2, wherein the polymer compound (C) has a mass average molecular weight of 20,000 to 500,000. The photoresist composition of claim 1, wherein the substrate component (A) is a resin component (A1) which increases polarity by an action of an acid. A method for forming a photoresist pattern, comprising the steps of forming a photoresist film using a photoresist composition according to any one of claims 1 to 4, and exposing the photoresist film to a support. And a step of developing the photoresist film to form a photoresist pattern.