JP4823562B2 - Resist pattern forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a negative resist composition having sensitivity to a g-line, an i-line, a KrF excimer laser and an electron beam and usable in a mix and match process where exposure is performed using at least two kinds of exposure light sources selected from a g-line, an i-line, a KrF excimer laser and an electron beam, and to provide a resist pattern forming method. <P>SOLUTION: The negative resist composition used in a process where exposure is performed using at least two kinds of exposure light sources selected from a g-line, an i-line, a KrF excimer laser and an electron beam contains an alkali-soluble resin component (A), an acid generator component (B) which generates an acid upon irradiation with a g-line, an i-line, a KrF excimer laser and an electron beam, and a crosslinker component (C). <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a negative resist composition and a resist pattern forming method used in an exposure process using at least two kinds of exposure light sources selected from g-line, i-line, KrF excimer laser and electron beam.

In the manufacture of semiconductor elements, liquid crystal display elements, and the like, a fine processing technique based on a lithography technique is used, and in recent years, the miniaturization is rapidly progressing due to the advancement of the lithography technique.
As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, as described above, ultraviolet rays typified by g-line and i-line have been used in the past, but now KrF excimer laser (248 nm) is the center of mass production, and ArF excimer laser ( 193 nm) is beginning to be introduced in mass production. Research is also being conducted on lithography technology using an F ₂ excimer laser (157 nm), extreme ultraviolet light (EUV), electron beam (EB) or the like as a light source (radiation source).

Resist materials used in lithography techniques are required to have sensitivity to an exposure light source. In general, a base resin having a film forming ability is used as a resist material. Conventionally, g-line and i-line are mainly used as an exposure light source. When these light sources are used, for example, in the case of a negative type, an alkali-soluble novolak resin as a base resin and a melamine resin or a urea resin as a crosslinking agent component Many negative resist compositions (non-chemically amplified) in combination with amino resins have been used.
With recent shortening of the wavelength of the exposure light source and miniaturization of the required dimensions, the resist material is required to further improve sensitivity and resolution with respect to the exposure light source. Therefore, in the KrF excimer laser and later, a chemically amplified resist composition containing a base resin and an acid generator that generates an acid upon exposure is mainly used as a resist material. As the chemically amplified resist, for example, in the case of the negative type, a resist containing mainly an alkali-soluble resin, an acid generator, and a crosslinking agent is mainly used. When forming a resist pattern, an acid is generated from the acid generator by exposure. When this occurs, the exposed area becomes insoluble in alkali.
In addition, the base resin used for the resist material is changing as the wavelength of the exposure light source is shortened. For example, when a KrF excimer laser is used as the light source, a polyhydroxystyrene (PHS) resin is mainly used. It has been. When an ArF excimer laser is used as a light source, a resin (acrylic resin) having a structural unit derived from (meth) acrylic acid in the main chain is generally used.

Further, as a means for forming a high-resolution pattern, studies have been made not only from materials but also from the viewpoint of processes.
For example, a three-layer resist method using a laminate in which an organic film, an intermediate film made of a silica-based inorganic film, and a resist film are stacked on a substrate, and superior in that the number of steps is smaller than the three-layer resist method. A multilayer resist method such as a two-layer resist method (see, for example, Patent Documents 1 and 2) has been proposed. In such a multilayer resist method, there is a possibility that high resolution can be realized.
However, the multilayer resist method has a problem of yield deterioration, throughput reduction, or cost due to an increase in the number of processes.

  The throughput problem is particularly serious in a lithography process using an electron beam. In such a lithography process, there is a possibility that high resolution can be realized. However, exposure is usually performed in vacuum by exposure through a desired mask pattern or direct writing. Therefore, since it is necessary to perform a decompression operation, a purge operation, etc., it takes time compared to a process using an excimer laser or the like. In particular, in direct writing using an electron beam, it takes a very long time to pattern the entire substrate.

Therefore, in recent years, a method of performing exposure using two or more kinds of light sources (hereinafter referred to as “mix and match”) has attracted attention.
In this method, for example, an entire pattern is usually formed using a light source necessary for forming a fine pattern, for example, an electron beam, and an electron beam is used for a fine pattern, and rough processing that does not require a very high resolution is required. With respect to the pattern, it is said that the throughput can be improved by using a light source other than that, for example, a KrF excimer laser, and exposing all at once through the mask pattern to shorten the time required for forming the rough pattern. .
JP-A-6-202338 JP-A-8-29987

However, generally, as described above, the composition of the resist material varies depending on the type of exposure light source used, and a plurality of light sources, for example, three or more types of light sources have no sensitivity. For example, non-chemically amplified resists used for g-line and i-line exposures usually do not have sensitivity to KrF excimer lasers or electron beams, and therefore cannot be used for mix-and-match using these light sources. . Therefore, there are limitations on the combinations of light sources that can be used for mix and match.
Therefore, there is an increasing demand for a resist material that can be used in mix and match using any of these light sources. Among them, a resist material that can be used for a mix-and-match in a combination of an electron beam capable of forming a high-resolution pattern and other light sources, especially a combination of g-line and / or i-line, which are generally widely used. Is strongly demanded.
The present invention has been made in view of the above circumstances, has sensitivity to g-line, i-line, KrF excimer laser and electron beam, and is selected from at least g-line, i-line, KrF excimer laser and electron beam. An object of the present invention is to provide a negative resist composition and a resist pattern forming method that can be used in a mix and match process in which exposure is performed using two types of exposure light sources.

［式（ＩＩＩ）中、ｍ’は０又は１；Ｘは１又は２；Ｒ_１は、１又はそれ以上のＣ_１−Ｃ_１２アルキル基が置換していてもよいフェニル基、ヘテロアリール基、又は、ｍ’が０の場合はさらにＣ_２−Ｃ_６アルコキシカルボニル基、フェノキシカルボニル基、ＣＮ（シアノ基）；Ｒ_２は、１又はそれ以上のＣ _１ −Ｃ _１２ アルキル基が置換していてもよいフェニル基、ヘテロアリール基、Ｃ _２ −Ｃ _６ アルコキシカルボニル基、フェノキシカルボニル基、又はＣＮ（シアノ基）；Ｒ_３’は、Ｘ＝１のときＣ_１−Ｃ_１８アルキル基、Ｘ＝２のときＣ_２−Ｃ_１２アルキレン基、フェニレン基；Ｒ_４，Ｒ_５は独立に水素原子、ハロゲン原子、Ｃ_１−Ｃ_６アルキル基；Ａは−Ｓ−、−Ｏ−を示す。］

［式（ＩＶ）中、Ｒ_１’はＣ_２−Ｃ_１２アルキレン基；Ｒ_２、Ｒ_４、Ｒ_５、Ａは上記と同義；Ｒ_３はＣ_１−Ｃ_１８アルキル基を示す。］
As a result of intensive studies, the present inventors have found that the above problems can be solved by selecting and using an acid generator component having a specific property, and completed the present invention.
That is, the first aspect of the present invention includes an alkali-soluble resin component (A), an g-line, i-line, KrF excimer laser and an acid generator component (B) that generates an acid upon irradiation with an electron beam, and a cross-linking agent component. A step of forming a resist film on a substrate using a negative resist composition containing (C), the resist film comprising at least one selected from g-line, i-line and KrF excimer laser, and an electron beam Using the step of selectively exposing, and the step of forming the resist pattern by alkali development of the resist film,
The acid generator component (B) is an oxime sulfonate acid generator represented by the following general formula (III) or (IV).

[In the formula (III), m ′ is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, a heteroaryl group, which may be substituted by one or more C ₁ -C ₁₂ alkyl groups, Or, when m ′ is 0, C ₂ -C ₆ alkoxycarbonyl group, phenoxycarbonyl group, CN (cyano group); R ₂ is substituted by one or more C ₁ -C ₁₂ alkyl groups A phenyl group, heteroaryl group, C ₂ -C ₆ alkoxycarbonyl group, phenoxycarbonyl group, or CN (cyano group) ; R ₃ ′ is a C ₁ -C ₁₈ alkyl group when X = 1, X = 2 R 4, _{R 5} are independently a hydrogen atom, a halogen _atom, C 1 -C _{6 alkyl;; C} 2 _{-C 12} alkylene group, a phenylene group when the a -S -, - O - shows the. ]

[In formula (IV), R ₁ ′ is a C ₂ -C ₁₂ alkylene group; R ₂ , R ₄ , R ₅ , A are as defined above; R ₃ is a C ₁ -C ₁₈ alkyl group. ]

  In the present invention, exposure includes electron beam irradiation.

  According to the present invention, there is sensitivity to g-line, i-line, KrF excimer laser and electron beam, and exposure is performed using at least two kinds of exposure light sources selected from g-line, i-line, KrF excimer laser and electron beam. A negative resist composition and a resist pattern forming method that can be used in the process can be provided. By using such a negative resist composition and a resist pattern forming method, the mix and match can be performed using any of g-line, i-line, KrF excimer laser, and electron beam.

<Negative resist composition>
The negative resist composition of the present invention is a negative resist composition used in a step of exposing using at least two exposure light sources selected from g-line, i-line, KrF excimer laser and electron beam, Soluble resin component (A) (hereinafter referred to as component (A)), g-line, i-line, KrF excimer laser and acid generator component (B) (hereinafter referred to as (B) component) that generates acid upon irradiation with electron beam And) a crosslinking agent component (C) (hereinafter referred to as component (C)).
In such a negative resist composition, when an acid generated from the component (B) by exposure acts, crosslinking occurs between the component (A) and the component (C), and the entire negative resist composition is alkali-insoluble. To change. Therefore, in the formation of a resist pattern, when a resist film made of the negative resist composition is selectively exposed or heated after exposure in addition to exposure, the exposed portion turns into alkali-insoluble while the unexposed portion is alkali-soluble. Therefore, a negative resist pattern can be formed by alkali development.

"(A) component"
The component (A) may be any component as long as it is soluble in an alkali developer and becomes insoluble in alkali by interaction with the component (C). Alkali-soluble resin of a chemically amplified negative resist composition so far It can be arbitrarily selected from those used as components.

The component (A) preferably used in the negative resist composition of the present invention is excellent in dry etching resistance, heat resistance, implantation resistance, ionic etching resistance such as ion milling, adhesion to a substrate, plating resistance, etc. Since it can be used for various applications, an alkali-soluble novolak resin (hereinafter sometimes simply referred to as a novolak resin) can be used.
The novolak resin is not particularly limited, and can be arbitrarily selected from those conventionally proposed as a film-forming substance that can be usually used in negative resist compositions, preferably aromatic. Mention may be made of novolak resins obtained by condensation reaction of hydroxy compounds with aldehydes and / or ketones.

  Examples of aromatic hydroxy compounds used for the synthesis of novolak resins include phenols; cresols such as m-cresol, p-cresol, o-cresol; 2,3-xylenol, 2,5-xylenol, 3,5-xylenol. Xylenols such as 3,4-xylenol; m-ethylphenol, p-ethylphenol, o-ethylphenol, 2,3,5-trimethylphenol, 2,3,5-triethylphenol, 4-tert-butylphenol, Alkylphenols such as 3-tert-butylphenol, 2-tert-butylphenol, 2-tert-butyl-4-methylphenol, 2-tert-butyl-5-methylphenol; p-methoxyphenol, m-methoxyphenol, p- Ethoxyphenol, -Alkoxyphenols such as ethoxyphenol, p-propoxyphenol, m-propoxyphenol; o-isopropenylphenol, p-isopropenylphenol, 2-methyl-4-isopropenylphenol, 2-ethyl-4-isopropenylphenol Isopropenyl phenols such as phenylphenol; arylphenols such as phenylphenol; polyhydroxyphenols such as 4,4′-dihydroxybiphenyl, bisphenol A, resorcinol, hydroquinone, pyrogallol and the like. These may be used alone or in combination of two or more.

Examples of aldehydes used in the synthesis of novolak resins include formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, butyraldehyde, trimethylacetaldehyde, acrolein, crotonaldehyde, cyclohexanealdehyde, furfural, furylacrolein, benzaldehyde, terephthalaldehyde, phenyl Acetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, o-chlorobenzaldehyde, m -Chlorobenzaldehyde, p-chloro Robenzaldehyde, cinnamic aldehyde and the like can be mentioned. These may be used alone or in combination of two or more.
Among these aldehydes, it is preferable to use formaldehyde because of its availability. In particular, since heat resistance is good, it is preferable to use formaldehyde in combination with hydroxybenzaldehydes such as o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, and p-hydroxybenzaldehyde.

Examples of the ketones used for the synthesis of the novolak resin include acetone, methyl ethyl ketone, diethyl ketone, and diphenyl ketone. These may be used alone or in combination of two or more.
Furthermore, the above aldehydes and ketones may be used in appropriate combination.

  The novolak resin can be produced by subjecting the aromatic hydroxy compound and aldehydes and / or ketones to a condensation reaction by a known method in the presence of an acidic catalyst. In this case, hydrochloric acid, sulfuric acid, formic acid, oxalic acid, paratoluenesulfonic acid, etc. can be used as the acidic catalyst.

  The mass average molecular weight (Mw) of the novolak resin (in terms of polystyrene by gel permeation chromatography (GPC)), that is, the Mw of the component (A) before being protected with the acid dissociable, dissolution inhibiting group is within the range of 2000 to 50000. It is preferable, 3000-20000 is more preferable, 4000-15000 is further more preferable. When the Mw is 2000 or more, the application property when the negative resist composition is dissolved in an organic solvent and applied onto the substrate is good, and when it is 50000 or less, the resolution is good.

In the present invention, the novolac resin is preferably one that has been subjected to a treatment for separating and removing the low molecular weight substance. Thereby, heat resistance improves further.
Here, the low molecular weight substance in this specification includes, for example, aromatic monomers, aldehydes, ketones, etc. used in the synthesis of novolak resin, residual monomers remaining without reaction, and 2 monomers. Molecularly bonded dimers, 3 molecularly linked trimers, etc. (monomers and 2-3 nuclei etc.) are included.
The low molecular weight fractionation method is not particularly limited. For example, a method of purifying using an ion exchange resin or a known method using a good solvent (such as alcohol) and a poor solvent (such as water) of the resin. A fractionation operation can be used. According to the former method, the acid component and the metal component can be removed together with the low molecular weight substance.
The yield in such a low molecular weight fraction removal treatment is desirably in the range of 50 to 95% by mass. If it is 50% by mass or more, the difference in dissolution rate between the exposed part and the unexposed part becomes large, and the resolution is good. Moreover, the effect by performing a separation removal is fully acquired as it is 95 mass% or less.
Further, the content of the low molecular weight substance having Mw of 500 or less is 15% or less, preferably 12% or less on the GPC chart. By setting it to 15% or less, the effect of improving the heat resistance of the resist pattern is exhibited, and at the same time, the effect of suppressing the amount of sublimate generated during the heat treatment is exhibited.

In the negative resist composition of the present invention, as the component (A), a resin having a structural unit derived from hydroxystyrene (hereinafter sometimes referred to as polyhydroxystyrene (PHS) resin) is also preferably used. By using such a resin, a high-resolution pattern can be formed. Further, since fine processing can be performed even in the case of a thick film, a pattern with a high aspect ratio can be formed, and as a result, resistance to dry etching and the like is improved.
Here, the term “hydroxystyrene” refers to hydroxystyrene and a hydrogen atom bonded to the α-position carbon atom of hydroxystyrene substituted with another substituent such as a halogen atom, an alkyl group, a halogenated alkyl group, And a derivative thereof (preferably, one having the above-described substituent bonded to a benzene ring or the like). The number of hydroxyl groups bonded to the benzene ring of hydroxystyrene is preferably an integer of 1 to 3, and more preferably 1. The α-position (α-position carbon atom) of hydroxystyrene is a carbon atom to which a benzene ring is bonded unless otherwise specified.
The “structural unit derived from hydroxystyrene” means a structural unit formed by cleavage of the ethylenic double bond of hydroxystyrene.
In the PHS resin, the proportion of structural units derived from hydroxystyrene is preferably 50 to 100 mol%, more preferably 80 to 100 mol%, based on the total of all structural units constituting the PHS resin.

Specific examples of the PHS resin include polyhydroxystyrene and hydroxystyrene-styrene copolymer.
Examples of the hydroxystyrene-styrene copolymer include a copolymer having a structural unit (a1) represented by the following general formula (I) and a structural unit (a2) represented by the following general formula (II). It is done.

（式中、Ｒは水素原子またはメチル基を表し、ｍは１〜３の整数を表す。）

(In the formula, R represents a hydrogen atom or a methyl group, and m represents an integer of 1 to 3.)

（式中、Ｒは水素原子又はメチル基を表し、Ｒ_１は炭素数１〜５のアルキル基を表し、ｎは０または１〜３の整数を表す。）

(In the formula, R represents a hydrogen atom or a methyl group, R ₁ represents an alkyl group having 1 to 5 carbon atoms, and n represents 0 or an integer of 1 to 3).

In the structural unit (a1) represented by the general formula (I), R is a hydrogen atom or a methyl group, and is preferably a hydrogen atom.
m is an integer of 1-3. Of these, m is preferably 1.
The position of the hydroxyl group may be any of the o-position, the m-position, and the p-position. However, since it is readily available and inexpensive, m is 1 and has a hydroxyl group at the p-position. preferable. When m is 2 or 3, arbitrary substitution positions can be combined.

In the structural unit (a2) represented by the general formula (II), R is a hydrogen atom or a methyl group, and is preferably a hydrogen atom.
R ₁ is a linear or branched alkyl group having 1 to 5 carbon atoms, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group. Group, neopentyl group and the like. Industrially, a methyl group or an ethyl group is preferable.
The n is 0 or an integer of 1 to 3. Of these, n is preferably 0 or 1, and is particularly preferably 0 industrially.
When n is 1, the substitution position of R ₁ may be any of the o-position, m-position, and p-position, and when n is 2 or 3, any substitution position is selected. Can be combined.

Moreover, as PHS-type resin, you may use what the 3-40 mol% of the hydrogen atom of the hydroxyl group of polyhydroxystyrene is substituted by the alkali-insoluble group, and, thereby, alkali solubility is reduced.
Moreover, as a PHS resin, 5 to 30 mol% of the hydrogen atoms of the hydroxyl group of the structural unit (a1) in the copolymer having the structural unit (a1) and the structural unit (a2) are substituted with an alkali-insoluble group. Those having reduced alkali solubility may be used.
Here, the “alkali insoluble group” is a substituent that lowers the alkali solubility of the unsubstituted alkali-soluble resin. For example, a tertiary alkoxycarbonyl group such as a tert-butoxycarbonyl group or a tert-amyloxycarbonyl group. Groups, lower alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and the like.

  The mass average molecular weight of the PHS-based resin is preferably 1000 to 10,000, and more preferably 2000 to 4000 when using at least a KrF excimer laser and / or an electron beam for mix-and-match.

  The content of the component (A) in the negative resist composition of the present invention may be adjusted according to the resist film thickness to be formed.

[Component (B)]
The component (B) may be any component that generates an acid upon irradiation with g-line, i-line, KrF excimer laser, or electron beam, and has been proposed as an acid generator for chemically amplified resists. Can be arbitrarily selected from the above.
Here, “generation of acid by irradiation with g-line, i-line, KrF excimer laser and electron beam” means that acid is generated when any of these is used as an exposure light source.
Whether or not the acid generator is an acid generator that generates an acid upon irradiation with g-line, i-line, KrF excimer laser and electron beam is, for example, a negative type containing the acid generator and component (A). When a resist composition was prepared and the resist film formed using the negative resist composition was selectively exposed and developed using g-line, i-line, KrF excimer laser, and electron beam, Whether the resist pattern is formed can be determined.

Acid generators that have been proposed for chemically amplified resists include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, poly ( There are various known diazomethane acid generators such as bissulfonyl) diazomethanes, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, and disulfone acid generators.
Among these, the oxime sulfonate-based acid generator has high transparency with respect to g-line, i-line, KrF excimer laser, and the like. For example, even when the resist film is a thick film having a film thickness of 100 nm to 5.0 μm, the exposure light is not emitted. This is preferable because it can sufficiently penetrate the resist film and form a high-resolution resist pattern.
Here, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), or a compound represented by the following general formula (III) or (IV). Thus, it has the property of generating an acid upon irradiation with radiation.

（式（Ｂ−１）中、Ｒ^２１、Ｒ^２２はそれぞれ独立に有機基を表す。）

(In formula (B-1), R ²¹ and R ²² each independently represents an organic group.)

The organic group of R ²¹ and R ^{22 is} a group containing a carbon atom, and 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.)) You may have.
The organic group for R ²¹ is preferably a linear, branched or cyclic alkyl group or aryl group. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.
As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.
The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R ²¹ is particularly preferably a C 1-4 alkyl group having no substituent or a C 1-4 fluorinated alkyl group.

As the organic group for R ²² , a linear, branched, or cyclic alkyl group, aryl group, or cyano group is preferable. As the alkyl group and aryl group for R ^22, the same alkyl groups and aryl groups as those described above for R ²¹ can be used.
R ²² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  As the oxime sulfonate acid generator, a compound represented by the following general formula (III) or (IV) (see USP 6004724) is preferably used because of its high acid generation efficiency with respect to electron beam irradiation.

［式（ＩＩＩ）中、ｍ’は０又は１；Ｘは１又は２；Ｒ_１は、１又はそれ以上のＣ_１−Ｃ_１２アルキル基が置換していてもよいフェニル基、ヘテロアリール基、又は、ｍ’が０の場合はさらにＣ_２−Ｃ_６アルコキシカルボニル基、フェノキシカルボニル基、ＣＮ（シアノ基）；Ｒ_２はＲ_１と同義；Ｒ_３’は、Ｘ＝１のときＣ_１−Ｃ_１８アルキル基、Ｘ＝２のときＣ_２−Ｃ_１２アルキレン基、フェニレン基；Ｒ_４，Ｒ_５は独立に水素原子、ハロゲン原子、Ｃ_１−Ｃ_６アルキル基；Ａは−Ｓ−、−Ｏ−、−Ｎ（Ｒ_６）−を示す。］

[In the formula (III), m ′ is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, a heteroaryl group, which may be substituted by one or more C ₁ -C ₁₂ alkyl groups, Or when m ′ is 0, C ₂ -C ₆ alkoxycarbonyl group, phenoxycarbonyl group, CN (cyano group); R ₂ is synonymous with R ₁ ; R ₃ ′ is C _1- when X = 1 C ₁₈ alkyl group, when X = 2, C ₂ -C ₁₂ alkylene group, phenylene group; R ₄ and R ₅ are independently hydrogen atom, halogen atom, C ₁ -C ₆ alkyl group; A is —S—, — _{O -, - N (R 6} ) - indicates a. ]

［式（ＩＶ）中、Ｒ_１’はＣ_２−Ｃ_１２アルキレン基；Ｒ_２、Ｒ_４、Ｒ_５、Ａは上記と同義；Ｒ_３はＣ_１−Ｃ_１８アルキル基を示す。］

[In formula (IV), R ₁ ′ is a C ₂ -C ₁₂ alkylene group; R ₂ , R ₄ , R ₅ , A are as defined above; R ₃ is a C ₁ -C ₁₈ alkyl group. ]

  As such a compound, a thiolene-containing oxime sulfonate represented by the following formula (V) is particularly preferable.

  In addition to these, the component (B) includes a triazine compound (VI) represented by the following formula (VI) [bis (trichloromethyl) triazine], the triazine compound (VI) and the following formula (VII). A triazine compound (VII) represented by [bis (trichloromethyl) triazine] in combination as desired (see JP-A-6-289614 and JP-A-7-34412), the following formula (VIII) And a compound represented by the following formula (IX).

（式中、Ｒ^６、Ｒ^７は、それぞれ炭素数１〜３のアルキル基を示す。）

(In formula, R < ⁶ >, R < ⁷ > shows a C1-C3 alkyl group, respectively.)

（式中、Ｚは、４−アルコキシフェニル基等を示す。）

(In the formula, Z represents a 4-alkoxyphenyl group or the like.)

（式中、Ａｒは置換又は未置換のフェニル基またはナフチル基；Ｒは炭素原子数１〜９のアルキル基；ｎは２又は３の整数を示す。）

(In the formula, Ar represents a substituted or unsubstituted phenyl group or naphthyl group; R represents an alkyl group having 1 to 9 carbon atoms; and n represents an integer of 2 or 3.)

  Specific examples of the triazine compound (VI) include 2- [2- (3,4-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [ 2- (3-methoxy-4-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-methoxy-4-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-ethoxy-4-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3 , 5-triazine, 2- [2- (3,4-diethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-ethoxy- 4-propoxy Enyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-4-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-4-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-dipropoxyphenyl) ethenyl] -4,6-bis (trichloromethyl)-, 3,5-triazine and the like. These triazine compounds may be used alone or in combination of two or more.

  Examples of the triazine compound (VII) used in combination with the triazine compound (VI) as desired include 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5- Triazine, 2- (4-ethoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-propoxyphenyl) -4,6-bis (trichloromethyl) -1, 3,5-triazine, 2- (4-butoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxynaphthyl) -4,6-bis (trichloromethyl) ) -1,3,5-triazine, 2- (4-ethoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-propoxynaphthyl) ) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-butoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- ( 4-methoxy-6-carboxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxy-6-hydroxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (5-methyl-) 2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (5-ethyl-2-furyl) ethenyl] -4,6-bis (trichloromethyl) ) -1,3,5-triazine, -[2- (5-propyl-2-furyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,5-dimethoxyphenyl) ethenyl]- 4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-methoxy-5-ethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3 5-triazine, 2- [2- (3-methoxy-5-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-ethoxy- 5-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,5-diethoxyphenyl) ethenyl] -4,6-bis (trichloro Methyl) -1,3,3 5-triazine, 2- [2- (3-ethoxy-5-propoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy- 5-methoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3-propoxy-5-ethoxyphenyl) ethenyl] -4,6-bis ( Trichloromethyl) -1,3,5-triazine, 2-2 (3,5-dipropoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (3 , 4-methylenedioxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [2- (3,4-methylenedioxyphenyl) ethenyl] -4,6-bis (Trichrome Methyl) -1,3,5-triazine. These triazine compounds may be used alone or in combination of two or more.

  These compounds may be used alone or in combination of two or more. Among the compounds exemplified above, in particular, the compound represented by the formula (V) and the compound represented by the formula (IX) are preferably used because of excellent acid generation efficiency with respect to an electron beam.

In the present invention, as the component (B), the oxime sulfonate acid generator and an onium salt acid generator may be used in combination.
Examples of the onium salt acid generator include compounds represented by the following general formula (b-1) or (b-2).

［式中、Ｒ^１”〜Ｒ^３”，Ｒ^５”〜Ｒ^６”は、それぞれ独立に、アリール基またはアルキル基を表し；Ｒ^４”は、直鎖、分岐または環状のアルキル基またはフッ素化アルキル基を表し；Ｒ^１”〜Ｒ^３”のうち少なくとも１つはアリール基を表し、Ｒ^５”〜Ｒ^６”のうち少なくとも１つはアリール基を表す。］

[Wherein R ¹ ″ to R ³ ″ and R ⁵ ″ to R ⁶ ″ each independently represents an aryl group or an alkyl group; R ⁴ ″ represents a linear, branched or cyclic alkyl group or fluorinated group. Represents an alkyl group; at least one of R ¹ ″ to R ³ ″ represents an aryl group, and at least one of R ⁵ ″ to R ⁶ ″ represents an aryl group.]

In formula (b-1), R ¹ ″ to R ³ ″ each independently represents an aryl group or an alkyl group. At least one of R ¹ ″ to R ³ ″ represents an aryl group. Of R ¹ ″ to R ³ ″, two or more are preferably aryl groups, and most preferably all R ¹ ″ to R ³ ″ are aryl groups.
The aryl group for R ¹ ″ to R ³ ″ is not particularly limited, and is, for example, an aryl group having 6 to 20 carbon atoms, in which part or all of the hydrogen atoms are alkyl groups, alkoxy groups It may or may not be substituted with a group, a halogen atom or the like. The aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.
The alkyl group that may be substituted for the hydrogen atom of the aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and is a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Is most preferred.
The alkoxy group that may be substituted for the hydrogen atom of the aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and most preferably a methoxy group or an ethoxy group.
The halogen atom that may be substituted for the hydrogen atom of the aryl group is preferably a fluorine atom.
The alkyl group for R 1 ^{"~R 3",} is not particularly limited, for example, a straight, include alkyl groups such as branched or cyclic. It is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decanyl group. A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.
Among these, it is most preferable that all of R ¹ ″ to R ³ ″ are phenyl groups.

R ⁴ ″ represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group.
The linear alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group is a cyclic group as indicated by R ¹ ″ and preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and more preferably 6 carbon atoms. Most preferably, it is -10.
The fluorinated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms. Also. The fluorination rate of the fluorinated alkyl group (ratio of fluorine atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%, and particularly those in which all hydrogen atoms are substituted with fluorine atoms. Since the strength of the acid is increased, it is preferable.
R ⁴ ″ is most preferably a linear or cyclic alkyl group or a fluorinated alkyl group.

In formula (b-2), R ⁵ ″ to R ⁶ ″ each independently represents an aryl group or an alkyl group. At least one of R ⁵ ″ to R ⁶ ″ represents an aryl group. Of R ⁵ ″ to R ⁶ ″, two or more are preferably aryl groups, and all of R ⁵ ″ to R ⁶ ″ are most preferably aryl groups.
As the aryl group for R ⁵ ″ to R ⁶ ″, the same as the aryl groups for R ¹ ″ to R ³ ″ can be used.
Examples of the alkyl group for R ⁵ ″ to R ⁶ ″ include the same as the alkyl group for R ¹ ″ to R ³ ″.
Among these, it is most preferable that all of R ⁵ ″ to R ⁶ ″ are phenyl groups.
"As ^{R 4} in the formula (b-1)" ^{R 4} in the In the formula (b-2) include the same as.

  Specific examples of the onium salt-based acid generator include diphenyliodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, bis (4-tert-butylphenyl) iodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, and triphenylsulfonium trifluoromethane. Sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, tri (4-methylphenyl) sulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethane Sulfonate, its heptafluoropropane sulphonate or its Nafluorobutane sulfonate, trifluoromethane sulfonate of monophenyldimethylsulfonium, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, trifluoromethane sulfonate of diphenylmonomethylsulfonium, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, (4- Trifluoromethanesulfonate of methylphenyl) diphenylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of (4-methoxyphenyl) diphenylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, tri (4 -Tert-bu E) phenylsulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or nonafluorobutanesulfonate, diphenyl (1- (4-methoxy) naphthyl) sulfonium trifluoromethanesulfonate, heptafluoropropanesulfonate or nonafluorobutanesulfonate Is mentioned. In addition, onium salts in which the anion portion of these onium salts is replaced with methanesulfonate, n-propanesulfonate, n-butanesulfonate, or n-octanesulfonate can also be used.

  Moreover, what replaced the anion part with the anion part represented by the following general formula (b-3) or (b-4) in the said general formula (b-1) or (b-2) can also be used. (The cation moiety is the same as (b-1) or (b-2)).

［式中、Ｘ”は、少なくとも１つの水素原子がフッ素原子で置換された炭素数２〜６のアルキレン基を表し；Ｙ”、Ｚ”は、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を表す。］

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with

X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, Preferably it is C3.
Y ″ and Z ″ are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 to 10 carbon atoms, preferably It is C1-C7, More preferably, it is C1-C3.
The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of Y ″ and Z ″ is preferably as small as possible because the solubility in the resist solvent is good within the above carbon number range.
In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, as the number of hydrogen atoms substituted with fluorine atoms increases, the strength of the acid increases, and high-energy light or electron beam of 200 nm or less The ratio of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all. Are a perfluoroalkylene group or a perfluoroalkyl group in which a hydrogen atom is substituted with a fluorine atom.
These can be used alone or in combination.

  (B) As for the compounding quantity of a component, 1-30 mass parts is preferable with respect to 100 mass parts of (A) component, and 1-20 mass parts is especially preferable.

"(C) component"
The component (C) is not particularly limited, and can be arbitrarily selected from cross-linking agents used in chemically amplified negative resist compositions known so far.
Specifically, for example, 2,3-dihydroxy-5-hydroxymethylnorbornane, 2-hydroxy-5,6-bis (hydroxymethyl) norbornane, cyclohexanedimethanol, 3,4,8 (or 9) -trihydroxytrimethyl Aliphatic cyclic carbonization having a hydroxyl group or a hydroxyalkyl group or both such as cyclodecane, 2-methyl-2-adamantanol, 1,4-dioxane-2,3-diol, 1,3,5-trihydroxycyclohexane Examples thereof include hydrogen or oxygen-containing derivatives thereof.

In addition, amino group-containing compounds such as melamine, acetoguanamine, benzoguanamine, urea, ethylene urea, propylene urea, glycoluril are reacted with formaldehyde or formaldehyde and a lower alcohol, and the hydrogen atom of the amino group is converted into a hydroxymethyl group or a lower alkoxymethyl. And a compound substituted with a group.
Of these, those using melamine are melamine-based crosslinking agents, those using urea are urea-based crosslinking agents, those using alkylene ureas such as ethylene urea and propylene urea are alkylene urea-based crosslinking agents, and glycoluril is used. This was called a glycoluril-based crosslinking agent.
The component (C) is preferably at least one selected from the group consisting of melamine-based crosslinking agents, urea-based crosslinking agents, alkylene urea-based crosslinking agents, and glycoluril-based crosslinking agents, and melamine-based crosslinking agents are particularly preferable. .

  Melamine-based crosslinking agents include compounds in which melamine and formaldehyde are reacted to replace the amino group hydrogen atom with a hydroxymethyl group, and melamine, formaldehyde and lower alcohol are reacted to convert the amino group hydrogen atom into a lower alkoxy group. Examples include compounds substituted with a methyl group. Specific examples include hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxybutyl melamine, and the like, among which hexamethoxymethyl melamine is preferable.

  Urea-based crosslinking agents include compounds in which urea and formaldehyde are reacted to replace amino group hydrogen atoms with hydroxymethyl groups, and urea, formaldehyde and lower alcohols are reacted to convert amino group hydrogen atoms into lower alkoxy groups. Examples include compounds substituted with a methyl group. Specific examples include bismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, bisbutoxymethylurea, etc. Among them, bismethoxymethylurea is preferable.

  Examples of the alkylene urea-based crosslinking agent include compounds represented by the following general formula (III).

（式中のＲ^１’とＲ^２’はそれぞれ独立に水酸基または低級アルコキシ基であり、Ｒ^３’とＲ^４’はそれぞれ独立に水素原子、水酸基または低級アルコキシ基であり、ｖは０または１〜２の整数である。）

(In the formula, R ^{1 ′} and R ^{2 ′} are each independently a hydroxyl group or a lower alkoxy group, R ^{3 ′} and R ^{4 ′} are each independently a hydrogen atom, a hydroxyl group or a lower alkoxy group, and v is 0 or 1) It is an integer of ~ 2.)

When R ^{1 ′} and R ^{2 ′} are lower alkoxy groups, they are preferably alkoxy groups having 1 to 4 carbon atoms, and may be linear or branched. R ^{1 ′} and R ^{2 ′} may be the same or different from each other. More preferably, they are the same.
When R ^{3 ′} and R ^{4 ′} are lower alkoxy groups, they are preferably alkoxy groups having 1 to 4 carbon atoms, and may be linear or branched. R ^{3 ′} and R ^{4 ′} may be the same or different from each other. More preferably, they are the same.
v is 0 or an integer of 1 to 2, preferably 0 or 1.
As the alkylene urea crosslinking agent, a compound in which v is 0 (ethylene urea crosslinking agent) and / or a compound in which v is 1 (propylene urea crosslinking agent) are particularly preferable.

  The compound represented by the general formula (III) can be obtained by condensation reaction of alkylene urea and formalin, and by reacting this product with a lower alcohol.

  Specific examples of the alkylene urea-based crosslinking agent include, for example, mono and / or dihydroxymethylated ethylene urea, mono and / or dimethoxymethylated ethylene urea, mono and / or diethoxymethylated ethylene urea, mono and / or dipropoxy Ethylene urea-based crosslinking agents such as methylated ethylene urea, mono and / or dibutoxymethylated ethylene urea; mono and / or dihydroxymethylated propylene urea, mono and / or dimethoxymethylated propylene urea, mono and / or diethoxymethyl Propylene urea crosslinkers such as propylene urea, mono and / or dipropoxymethylated propylene urea, mono and / or dibutoxymethylated propylene urea; 1,3-di (methoxymethyl) 4,5-dihydroxy-2- Imidazolidinone 1,3-mentioned and (methoxymethyl) -4,5-dimethoxy-2-imidazolidinone.

Examples of the glycoluril-based crosslinking agent include glycoluril derivatives in which the N position is substituted with one or both of a hydroxyalkyl group and an alkoxyalkyl group having 1 to 4 carbon atoms. Such a glycoluril derivative can be obtained by a condensation reaction between glycoluril and formalin and by reacting this product with a lower alcohol.
Specific examples of the glycoluril-based crosslinking agent include, for example, mono, di, tri and / or tetrahydroxymethylated glycoluril, mono, di, tri and / or tetramethoxymethylated glycoluril, mono, di, tri and / or Examples include tetraethoxymethylated glycoluril, mono, di, tri and / or tetrapropoxymethylated glycoluril, mono, di, tri and / or tetrabutoxymethylated glycoluril.

As the component (C), one type may be used alone, or two or more types may be used in combination.
(C) As for the compounding quantity of a component, 3-30 mass parts is preferable with respect to 100 mass parts of (A) component, 3-15 mass parts is more preferable, and 5-10 mass parts is the most preferable. When the content of the component (C) is at least the lower limit value, the crosslinking formation proceeds sufficiently and a good resist pattern can be obtained. Moreover, when it is below this upper limit, the storage stability of the resist coating solution is good, and the deterioration of sensitivity with time is suppressed.

"Optional ingredients"
The negative resist composition of the present invention may further contain a nitrogen-containing organic compound (D) (hereinafter referred to as “component (D)”) in order to improve the resist pattern shape, the stability over time, and the like. preferable.
The component (D) is not particularly limited as long as it has compatibility with other components in the negative resist composition. For example, it is described in JP-A-9-6001. A compound can be mentioned.
In particular, the amount of an acid component that may be by-produced in the negative resist composition over time by blending a relatively bulky specific basic compound (d1) represented by the following general formula (X) The long-term storage stability of the negative resist composition can be improved.

In the general formula (X), one or more (preferably two or more, most preferably three) of X, Y and Z are (1) linear or branched alkyl having 4 or more carbon atoms. And (2) at least one group selected from the group consisting of a cyclic alkyl group having 3 or more carbon atoms, (3) a phenyl group, and (4) an aralkyl group.
In the alkyl group having 4 or more carbon atoms of (1), having 4 or more carbon atoms is effective in improving the temporal stability. The number of carbon atoms is preferably 5 or more, particularly 8 or more. The upper limit of the number of carbon atoms is not particularly limited, but is preferably 20 or less, particularly preferably 15 or less, from the viewpoint that a time-stable effect is recognized and it is commercially available. In addition, when it exceeds 20, basic strength will become weak and there exists a possibility that the effect of storage stability may not fully be acquired.
The alkyl group of (1) may be linear or branched. A straight chain is particularly preferable, and specifically, for example, an n-decyl group, an n-octyl group, an n-pentyl group, and the like are preferable.
In the (2) cyclic alkyl group having 3 or more carbon atoms, a cycloalkyl group having 4 to 8 carbon atoms is particularly commercially available, and is excellent in the effect of improving the temporal stability. Particularly preferred is a cyclohexyl group having 6 carbon atoms.
The aralkyl group of (4) is a group obtained by removing one hydrogen atom from the side chain of an aromatic hydrocarbon having a side chain, and is represented by the general formula -R'-P (R 'is an alkylene group, and P is an aryl group). Can be expressed as Examples of the aryl group of P include a phenyl group and a naphthyl group, and a phenyl group is preferable. The alkylene group for R ′ may have 1 or more carbon atoms, preferably 1 to 3 carbon atoms.
As the aralkyl group of (4), a benzyl group, a phenylethyl group and the like are preferable.

One or two of X, Y, and Z may be groups or atoms other than the above (1) to (4). As the group or atom other than (1) to (4), (1 ′) a group or atom selected from the group consisting of a linear or branched alkyl group having 3 or less carbon atoms and (2 ′) a hydrogen atom It is preferable that
The alkyl group having 3 or less carbon atoms (1 ′) may be either linear or branched. In particular, a methyl group and an ethyl group are preferable.

  X, Y and Z may be the same or different from each other, but when two or more of X, Y and Z are groups selected from the above (1) to (4), The groups corresponding to these are preferably the same from the viewpoint of the stability of the effect.

As the basic compound (d1), those constituting a tertiary amine are preferable, and among X, Y, and Z, those other than (1) to (4) are selected from (1 ′). Is preferred. Specific examples include tri-n-decylamine, methyl-di-n-octylamine, tri-n-pentylamine, N, N-dicyclohexylmethylamine, tribenzylamine and the like.
Among these, at least one selected from tri-n-decylamine, methyl-di-n-octylamine, and tri-n-pentylamine is preferable, and tri-n-decylamine is particularly preferable.

  As the component (D), a pyridine compound can also be used. In particular, 2,6-lutidine is preferable because it is excellent in the stability of holding after exposure.

As the component (D), any one of these may be used alone, or two or more may be mixed and used.
(D) component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

In addition, the negative resist composition of the present invention includes an organic carboxylic acid as an optional component for the purpose of preventing sensitivity deterioration due to the blending of the component (D), and improving the resist pattern shape and the stability of placement. Acid or phosphorus oxo acid or its derivative (E) (hereinafter referred to as component (E)) can be contained. In addition, (D) component and (E) component can also be used together, and any 1 type can also be used.
As the organic carboxylic acid, for example, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Phosphorus oxoacids or derivatives thereof include phosphoric acid, phosphoric acid di-n-butyl ester, phosphoric acid diphenyl ester and other phosphoric acid or derivatives thereof such as phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid- Like phosphonic acids such as di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid dibenzyl ester and derivatives thereof, phosphinic acids such as phosphinic acid, phenylphosphinic acid and their esters Among these, phosphonic acid is particularly preferable.
(E) A component is used in the ratio of 0.01-5.0 mass parts per 100 mass parts of (A) component.

It is preferable to add a storage stabilizer to the negative resist composition of the present invention because the decomposition reaction of the organic solvent can be suppressed as described later.
The storage stabilizer is not particularly limited as long as it has an action of suppressing the decomposition reaction of the organic solvent, and examples thereof include an antioxidant as described in JP-A No. 58-94834. Can do. As the antioxidant, phenolic compounds and amine compounds are known, and phenolic compounds are particularly preferable, and 2,6-di (tert-butyl) -p-cresol and derivatives thereof are ester solvents. It is effective in terms of deterioration of the ketone solvent, is commercially available, is inexpensive, and is preferable in view of excellent storage stability. In particular, the effect of preventing deterioration of propylene glycol monoalkyl ether acetate and 2-heptanone is extremely excellent.

The negative resist composition of the present invention preferably further contains a dye.
The dye in the present invention has absorption for at least one of the light sources used for mix-and-match among g-line, i-line and KrF excimer laser. The sensitivity to i-line or KrF excimer lasers can be controlled and the balance with the sensitivity to at least one other light source (eg, electron beam) can be adjusted. In addition, the influence of standing waves by g-line, i-line, or KrF excimer lasers is reduced, line edge roughness (LER) is reduced, uniformity of the pattern dimensions to be formed, and depth of focus are improved. Achieved.

  The negative resist composition of the present invention may further contain miscible additives as desired, for example, additional resins for improving the performance of the resist film, surfactants for improving applicability, dissolution inhibitors, A plasticizer, a colorant, an antihalation agent, and the like can be appropriately added and contained.

The negative resist composition of the present invention can be produced by dissolving the material in an organic solvent.
Any organic solvent may be used as long as it can dissolve each component to be used to form a uniform solution, and one or two kinds of conventionally known solvents for chemically amplified resists can be used. These can be appropriately selected and used.
For example, lactones such as γ-butyrolactone, ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, 2-heptanone, ethylene glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate Polyhydric alcohols such as dipropylene glycol or dipropylene glycol monoacetate monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether and derivatives thereof, cyclic ethers such as dioxane, Methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, Methyl Kishipuropion acid, esters such as ethyl ethoxypropionate can be exemplified.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
A mixed solvent obtained by mixing propylene glycol monomethyl ether acetate (PGMEA) and a polar solvent is preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
Although the amount of the organic solvent used is not particularly limited, it is a concentration that can be applied to a substrate or the like and is appropriately set according to the coating film thickness. Generally, the solid content concentration of the resist composition is 2 to 60. It is used so that it may become in the range of 5 mass%, Preferably it is 5-50 mass%, More preferably, it is 5-40 mass%.

In addition, some of these organic solvents may decompose with time to generate acid as a by-product, but in the presence of the component (D) or in the presence of a storage stabilizer, the decomposition reaction may occur. Is suppressed. In particular, among the organic solvents described above, the effect is remarkable in ester solvents such as PGMEA and esters such as butyl acetate. Therefore, in the presence of the component (D) and / or the storage stabilizer, an ester solvent is preferable as the organic solvent, and PGMEA is particularly preferable.
In addition, as an acid component byproduced by the said decomposition | disassembly, in the case of 2-heptanone, formic acid, acetic acid, propionic acid, etc. are confirmed to be produced.

The negative resist composition of the present invention described above is used for the exposure process using at least two kinds of exposure light sources selected from g-line, i-line, KrF excimer laser and electron beam.
Since the negative resist composition of the present invention has sensitivity to any of g-line, i-line, KrF excimer laser and electron beam, the exposure light source is g-line, i-line, KrF excimer laser. Either electron beam or electron beam may be selected.
In the present invention, it is particularly preferable to use at least an electron beam as an exposure light source because a fine pattern can be formed. That is, the step is preferably a step of performing exposure using at least one selected from g-line, i-line and KrF excimer laser and an electron beam. In this case, a fine pattern, for example, a fine pattern having a dimension of 200 nm or less is formed using an electron beam, and a rougher pattern, for example, a pattern having a dimension exceeding 200 nm, is formed by g-line, i-line or KrF excimer laser. Use to form. Thereby, compared with the case where only an electron beam is used, for example, the throughput can be greatly improved.
Furthermore, considering that the exposure apparatus is inexpensive and the cost can be reduced, it is preferable to use g-line and / or i-line. That is, the step is preferably a step of exposing using g-line and / or i-line and electron beam.
In particular, when two types of exposure light sources are used as the exposure light source, it is preferable to use i-line and electron beam.

  The negative resist composition of the present invention is suitable for the resist pattern forming method of the present invention described below including a step of exposing using at least two kinds of exposure light sources selected from g-line, i-line, KrF excimer laser and electron beam. Used.

<Resist pattern formation method>
The resist pattern forming method of the present invention includes a step of forming a resist film on a substrate using the negative resist composition of the present invention, and the resist film is selected from g-line, i-line, KrF excimer laser, and electron beam The step of selectively exposing using at least two types of exposure light sources, and the step of forming the resist film by alkali development of the resist film.

The resist pattern forming method of the present invention can be performed, for example, as follows.
That is, first, the negative resist composition of the present invention is applied onto a substrate such as a silicon wafer with a spinner or the like, and prebaked at a temperature of 60 to 180 ° C. for 10 to 600 seconds, preferably 60 to 90 seconds. And a resist film is formed. The film thickness of the resist film is not particularly limited. In particular, the resist film has a thickness of 100 nm to 10 μm, more preferably 200 nm to 5 μm.
The resist film is selectively exposed with or without a desired mask pattern using one type (first exposure light source) selected from g-line, i-line, KrF excimer laser and electron beam. . That is, exposure is performed through the mask pattern, or drawing is performed by direct irradiation with an electron beam without using the mask pattern.
Next, a desired mask pattern is formed on the resist film using one type (second exposure light source) other than the first exposure light source selected from g-line, i-line, KrF excimer laser, and electron beam. Selectively expose with or without.
After the selective exposure, heat treatment (post-exposure baking (PEB)) is performed for 40 to 120 seconds, preferably 60 to 90 seconds, at a temperature of 80 to 150 ° C. Subsequently, a resist pattern can be formed by developing this using an alkali developing solution, for example, 0.1-10 mass% tetramethylammonium hydroxide (TMAH) aqueous solution.
An organic or inorganic antireflection film can be provided between the substrate and the coating layer of the resist composition.

The combination of the first exposure light source and the second exposure light source is not particularly limited, and can be arbitrarily selected from g-line, i-line, KrF excimer laser, and electron beam.
In the present invention, as described above, a combination of at least one selected from g-line, i-line and KrF excimer laser and an electron beam is preferable, and a combination of g-line and / or i-line and electron beam. Is more preferable, and a combination of i-line and electron beam is most preferable.

  The resist pattern thus formed can be used for etching using the resist pattern as a mask, plating using the resist pattern as a frame, and the like. Therefore, it can be used for manufacturing MEMS (Micro Electro Mechanical Systems) in which these steps are performed. MEMS is an advanced small system in which various fine structures (functional elements such as sensors, conductor structures such as wiring and connection terminals) are integrated on a substrate by micromachining technology. Specifically, as a MEMS, a magnetic head of a magnetic recording medium, a perpendicular magnetic head, an MRAM [(Magnetic Random Access Memory): a magneto-resistive GMR (giant magnetoresistive) film or a TMR (tunnel magnetoresistive) film as a memory element. Non-volatile memory used. ] Etc. can be illustrated.

EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited to a following example.
Examples 1-2 and Comparative Examples 1-2
Each component shown in Table 1 below was mixed and dissolved to prepare a negative resist composition solution.
In Table 1, the numerical value in [] indicates the blending amount (part by mass). Moreover, the symbol in Table 1 has the following meaning.
(A) -2: Mw = 2500 polyhydroxystyrene (trade name: VPS-2520, manufactured by Nippon Soda Co., Ltd.)
(A) -4: A novolak resin with Mw = 4000 synthesized by a conventional method using m-cresol and mixed aldehydes of formaldehyde / salicylaldehyde = 1 / 0.3 (molar ratio).
(B) -1: Compound (B) -2: Triphenylsulfonium nonafluorobutanesulfonate (C) -1: Melamine-based crosslinking agent (trade name: MW100LM, manufactured by Sanwa Chemical Co., Ltd.) represented by the above formula (V) )
(D) -2: tri-n-decylamine (D) -3: tri-n-pentylamine (E) -1: salicylic acid Add2: surfactant (trade name: XR-104, manufactured by Dainippon Ink & Chemicals, Inc. )
Add3: Dye (trade name: HHBP, manufactured by Daitokemix)
(S) -2: PGMEA

Subsequently, the following evaluation was performed about the obtained negative resist composition.
[Sensitivity to electron beam]
The obtained negative resist composition solution was uniformly applied onto an 8-inch silicon substrate that had been subjected to hexamethyldisilazane treatment, and was baked (PAB) at 130 ° C. for 90 seconds to form a film. A resist film having a thickness of 500 nm was obtained.
The resist film was drawn by an electron beam drawing machine (Hitachi HL-800D, 70 kV acceleration voltage), and then baked (PEB) at 110 ° C. for 90 seconds to obtain 2.38 mass% TMAH. Developed with an aqueous solution (23 ° C.) for 60 seconds.
Thereafter, whether or not a pattern was formed on the substrate was observed with a scanning electron microscope (SEM).
As a result, it was found that both Example 1 and Comparative Example 1 had a pattern, and had sensitivity to electron beams.

  Further, in the evaluation of the sensitivity to the electron beam, the limit resolution (nm) at the optimum exposure amount Eop at which a trench pattern with a width of 80 nm is formed was obtained. The results are shown in Table 2 as “resolution”.

[Sensitivity to KrF excimer laser]
A resist film having a thickness of 500 nm was formed in the same manner as described above, and a KrF excimer was applied to the resist film using a KrF exposure apparatus FPA3000EX3 (manufactured by Canon; NA (numerical aperture) = 0.55, σ = 0.55). After selectively irradiating with a laser (248 nm) through a mask pattern, the substrate was baked (PEB) at 110 ° C. for 90 seconds, and developed with a 2.38 mass% TMAH aqueous solution (23 ° C.) for 60 seconds.
As a result of observing whether or not a pattern was formed on the substrate by SEM, it was found that the pattern was formed in both Example 1 and Comparative Example 1, and it had sensitivity to a KrF excimer laser.

[Sensitivity to g-line]
In the same manner as described above, a resist film having a thickness of 500 nm was formed, and the resist film was selectively irradiated with g-rays (436 nm) through a mask pattern by NSR-1505G7E (manufactured by Nikon Corporation). The substrate was baked (PEB) at 110 ° C. for 90 seconds, and developed with a 2.38 mass% TMAH aqueous solution (23 ° C.) for 60 seconds.
As a result, it was found that the pattern was formed for Example 1 and it had sensitivity to g-line. On the other hand, in Comparative Example 1, it was found that no pattern was formed and there was no sensitivity to g-line.

[Sensitivity to i-line]
A resist film having a thickness of 500 nm is formed in the same manner as described above, and the resist film is selectively irradiated with i-line (365 nm) through a mask pattern by NSR2205i14E (manufactured by Nikon), and then 110 ° C. The substrate was baked for 90 seconds (PEB) and developed with a 2.38 mass% TMAH aqueous solution (23 ° C.) for 60 seconds.
As a result, it was found that a pattern was formed in Example 1 and sensitivity to i-line was obtained. On the other hand, in Comparative Example 1, it was found that no pattern was formed and there was no sensitivity to i-line.

As is clear from these results, the negative resist compositions of Examples 1 and 2 have sensitivity to all exposure light sources of g-line, i-line, KrF excimer laser, and electron beam. Mix and match can be performed by arbitrarily selecting two or more of them. Moreover, the resist pattern formed also had high resolution.
On the other hand, the negative resist compositions of Comparative Examples 1 and 2 using only (B) -2 as the component (B) have sensitivity to the KrF excimer laser and the electron beam. Although a resolution pattern could be formed, the g-line and i-line had no sensitivity. Therefore, the negative resist compositions of Comparative Examples 1 and 2 cannot be used to arbitrarily mix and match two or more of g-line, i-line, KrF excimer laser, and electron beam. Is clear.

Next, an actual mix and match was performed. That is, using the negative resist composition of Example 1, a resist pattern was formed by mix and match using i-line and electron beam according to the procedure shown in FIGS. The i-line and electron beam exposure conditions are the same as those used in the above evaluation. 1 to 3 are illustrated by partially changing the scale from the actual dimensions for convenience of explanation.
First, a resist film was formed in the same manner as described above on a base film of a laminate in which a magnetic film was stacked on a substrate and a base film was further stacked thereon. The base film was formed using TBLC-100 manufactured by Tokyo Ohka Kogyo Co., Ltd.
Next, as shown in FIG. 1, large-area patterns 11 and 11 of 5 μm square were formed at 1 μm intervals with i line. Next, as shown in FIG. 2, a line pattern 12 having a width of 100 nm was formed by an electron beam so as to connect the large area patterns 11 and 11. In this way, a resist pattern 13 having a shape in which the large area patterns 11 and 11 are connected by the line pattern 12 was formed. A perspective view of the resist pattern 13 is shown in FIG.
At this time, the underlying film located under the removed portion of the resist film was removed by over-etching, and the underlying pattern 3 was formed. FIG. 4 shows a longitudinal sectional view of the line pattern 12 portion. As shown in FIG. 4, a cross-sectional wing plate-like pattern 5 including a base pattern 3 and a line pattern 12 was formed on the magnetic film 2 ′ laminated on the substrate 1.

Next, using the pattern 5, the lead portion of the magnetic head was formed by the procedure shown in FIG.
First, using the pattern 5 as a mask, ion milling was performed using an IML series ion beam milling device manufactured by Hitachi, Ltd. As shown in FIG. The magnetic film 2 ′ below the pattern 5 remains and the magnetic film pattern 2 is printed.
Further, when sputtering was performed using a sputtering apparatus ISM-2200 manufactured by Hitachi, Ltd., as shown in FIG. 5B, the pattern 5 and the substrate 1 around the magnetic film pattern 2 were An electrode film 6 was formed.
Finally, the base pattern 3 is etched by dry etching to remove the pattern 5 (lift-off), whereby as shown in FIG. 5C, the substrate 1 and the magnetic film pattern 2 formed thereon, A lead portion 10 of a magnetic head comprising the electrode film 6 formed around the periphery was manufactured.

It is a figure for demonstrating the process of forming a resist pattern by the mix and match using i line | wire and an electron beam. It is a figure for demonstrating the process of forming a resist pattern by the mix and match using i line | wire and an electron beam. It is a perspective view which shows the resist pattern formed by the mix and match using i line | wire and an electron beam. It is sectional drawing of the pattern formed by the mix and match using i line | wire and an electron beam. It is a figure for demonstrating the process of forming the lead part of a magnetic head using the pattern formed by the mix and match using i line | wire and an electron beam.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 '... Magnetic film, 2 ... Magnetic film pattern, 3 ... Base pattern, 5 ... Pattern, 6 ... Electrode film, 10 ... Magnetic head (lead part), 11 ... Large area pattern, 12 ... Line pattern, 13 ... resist pattern

Claims (4)

Negative resist composition containing an alkali-soluble resin component (A), an acid generator component (B) that generates an acid upon irradiation with g-line, i-line, KrF excimer laser, and electron beam, and a crosslinking agent component (C) A step of forming a resist film on a substrate using the method, a step of selectively exposing the resist film using at least one selected from g-line, i-line and KrF excimer laser and an electron beam, and Including a step of alkali-developing the resist film to form a resist pattern,
The method for forming a resist pattern, wherein the acid generator component (B) is an oxime sulfonate acid generator represented by the following general formula (III) or (IV).

[In the formula (III), m ′ is 0 or 1; X is 1 or 2; R ₁ is a phenyl group, a heteroaryl group, which may be substituted by one or more C ₁ -C ₁₂ alkyl groups, Or, when m ′ is 0, C ₂ -C ₆ alkoxycarbonyl group, phenoxycarbonyl group, CN (cyano group); R ₂ is substituted by one or more C ₁ -C ₁₂ alkyl groups A phenyl group, heteroaryl group, C ₂ -C ₆ alkoxycarbonyl group, phenoxycarbonyl group, or CN (cyano group) ; R ₃ ′ is a C ₁ -C ₁₈ alkyl group when X = 1, X = 2 R 4, _{R 5} are independently a hydrogen atom, a halogen _atom, C 1 -C _{6 alkyl;; C} 2 _{-C 12} alkylene group, a phenylene group when the a -S -, - O - shows the. ]

[In formula (IV), R ₁ ′ is a C ₂ -C ₁₂ alkylene group; R ₂ , R ₄ , R ₅ , A are as defined above; R ₃ is a C ₁ -C ₁₈ alkyl group. ]   The resist pattern forming method according to claim 1, wherein the alkali-soluble resin component (A) is an alkali-soluble novolak resin.   The resist pattern forming method according to claim 1, wherein the alkali-soluble resin component (A) is a resin having a structural unit derived from hydroxystyrene.   The resist pattern forming method according to claim 1, wherein the negative resist composition further contains a nitrogen-containing organic compound (D).

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