JP2002236364A - Negative type resist composition for electron beam or x-ray - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a negative type resist composition for electron beam or X-rays excellent in uniformity of coating on the surface of a substrate and suppressing the occurrence of defects in development. SOLUTION: The negative type resist composition for electron beam and X-rays contains a crosslinker which causes a crosslinking reaction under the action of an acid and a mixed solvent containing at least one selected from the group (a) comprising propylene glycol monoalkyl ether carboxylates and at least one selected from the group (b) comprising propylene glycol monoalkyl ethers, alkyl lactates and alkyl alkoxypropionates and the group (c) comprising γ-butyrolactone, ethylene carbonate and propylene carbonate. The crosslinker is a phenol derivative containing 3-10 benzene ring forming atomic groups and the molecular weight is <=2,000. The derivative has one or more hydroxymethyl groups and one or more alkoxymethyl groups in one molecule and these groups bond to at least one of the benzene ring forming atomic groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative resist composition suitable for use in ultra microlithography processes such as the production of ultra LSIs and high capacity microchips, and other photofabrication processes. More specifically, X including an excimer laser beam
The present invention relates to a negative-type chemically amplified resist composition capable of forming a high-definition pattern using an electron beam, an electron beam or the like, and is particularly preferably used for fine processing of a semiconductor element using a high energy beam such as an electron beam. The present invention relates to a negative chemically amplified resist composition which can be used.

[0002]

2. Description of the Related Art The degree of integration of integrated circuits is increasing, and in the manufacture of semiconductor substrates such as VLSI, processing of ultrafine patterns having a line width of less than half a micron is required. Have been. In order to meet the need, the wavelength of an exposure apparatus used for photolithography is becoming shorter and shorter, and now far ultraviolet light and excimer laser light (XeCl, KrF, ArF, etc.) have been studied. . Further, formation of finer patterns by electron beams or X-rays has been studied.

In particular, electron beams or X-rays are positioned as a next-generation or next-next-generation pattern forming technology, and development of a negative resist capable of achieving a high sensitivity, a high resolution and a rectangular profile is desired. In electron beam lithography, accelerated electron beams emit energy in the process of causing collision and scattering with atoms constituting a resist material, thereby exposing the resist material to light. The use of a highly accelerated electron beam increases the straightness, reduces the effects of electron scattering, and makes it possible to form a high-resolution rectangular pattern.On the other hand, the electron beam permeability increases, The sensitivity decreases. As described above, in electron beam lithography, there is a trade-off between sensitivity and resolution / resist shape, and there has been a problem of how to achieve both.

Conventionally, various proposals have been made for an acid generator for a chemically amplified negative resist. Japanese Patent Publication No. 8-3635 discloses an organic halogen compound, JP-A-2-150848, and JP-A-6-1997770 discloses an iodonium salt and a sulfonium salt.
8, JP-A-4-366864, JP-A-4-366865
An acid generator containing Cl and Br in JP-A-4-210
960, diazodisulfone in JP-A-4-217249,
Diazosulfone compounds, triazine compounds described in JP-A-4-226454, JP-A-3-87746, JP-A-4-29
1259, JP-A-6-236024, U.S. Pat.
742 each disclose a sulfonate compound. Also, as for the crosslinking agent, methylol melamine, resol resin, epoxidized novolak resin,
Urea resins and the like have been used. However, the conventional resist has problems of insufficient coating uniformity on the substrate and generation of defects during development.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a negative resist composition for an electron beam or an X-ray which has excellent coating uniformity on a substrate surface and reduces occurrence of defects during development. It is in.

[0006]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that in a negative-type chemical amplification system, the above objects of the present invention depend on the type of the photosensitive composition, The present invention has been found to be attained by using a mixed solvent. That is, the present invention is achieved by the following configurations. (1) At least the following (A), (B), (C1),
A negative resist composition for electron beam or X-ray, comprising (D) and (E). (A) an alkali-soluble resin (B) an acid generator (C1) a phenol derivative containing 3 to 10 benzene ring atoms in the molecule, a molecular weight of 2000 or less, and a hydroxymethyl group and an alkoxymethyl group in the molecule each having 1 (D) Organic basic compound (E) At least one of the solvents in the following group a: Seed and b below
Group A: mixed solvent containing at least one of the following Group c solvents: Group a: propylene glycol monoalkyl ether carboxylate Group b: propylene glycol monoalkyl ether, alkyl lactate and alkyl alkoxypropionate Group c: γ- Butyrolactone, ethylene carbonate and propylene carbonate (2) The negative resist composition for electron beam or X-ray according to (1), further comprising (C2) and / or (C3) below. (C2) a phenol derivative containing 3 to 10 benzene ring groups in the molecule, having a molecular weight of 2,000 or less, containing no hydroxymethyl group, and having two or more alkoxymethyl groups in the molecule, and having at least one of them (C3) A phenol derivative containing 3 to 10 benzene ring atoms in the molecule, having a molecular weight of 2,000 or less and containing an alkoxymethyl group. A crosslinking agent which has two or more hydroxymethyl groups in a molecule and is bonded to at least one of the benzene ring groups, and which exhibits a crosslinking reaction by the action of an acid (3) (B) an acid generator The following general formulas (I) to (II)
The negative resist composition for electron beams or X-rays according to (1) or (2), which is a compound represented by any one of (I).

[0007]

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[In the general formulas (I) to (III), R _{1 to} R
₃₇ is each independently a hydrogen atom, an alkyl group, an alkoxyl group, a hydroxyl group, a halogen atom, or -SR ₃₈
Represents a group represented by R ₃₈ represents an alkyl group or an aryl group. In the case of R _{1 to} R ₁₅ , two or more selected from R _{1 to} R ₁₅ may be directly bonded to each other at the terminal, or may be bonded to each other via an element selected from oxygen, sulfur and nitrogen to form a ring structure. Good. In the case of R _{16 to} R ₂₇ , a ring structure may be similarly formed. In the case of R _{28 to} R ₃₇ ,
Similarly, a ring structure may be formed. X ^- represents an anion of an organic sulfonic acid. (4) In the acid generators of the general formulas (I) to (III),
X ^- is benzenesulfonic acid, naphthalenesulfonic acid,
Or an anion of an organic sulfonic acid selected from anthracene sulfonic acid, and part or all of hydrogen atoms are substituted with fluorine atoms, or part or all of hydrogen atoms are substituted with fluorine atoms The negative resist composition for electron beam or X-ray according to (3), which is substituted with an organic group.

Embodiments of the negative resist composition of the present invention include the following. A negative resist containing an alkali-soluble resin, an acid generator, a cross-linking agent, an organic basic compound, and an organic solvent, wherein the cross-linking agent has a benzene ring atom group of 3 to 1 in the molecule.
It is a phenol derivative containing 0, having a molecular weight of 2,000 or less, having at least one hydroxymethyl group and at least one alkoxymethyl group in the molecule, and linking them to at least one of the benzene ring atoms. Is a cross-linking agent. Alkali-soluble resin, general formula (I) to general formula (III)
An acid generator, a cross-linking agent, an organic basic compound, a negative resist containing an organic solvent, the cross-linking agent is a phenol derivative containing 3 to 10 benzene ring atoms in the molecule, The molecular weight is 2000 or less, and a hydroxymethyl group and an alkoxymethyl group are each 1 in the molecule.
And is a cross-linking agent cross-linked by an acid. In the present invention, of the above and the above embodiments, the embodiment in which the effect of the present invention is further improved is preferable.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The compounds used in the present invention will be described below. (A) Alkali-soluble resin used in the present invention In the present invention, an alkali-soluble resin is used together with an acid generator and the like. The alkali-soluble resin used together with the acid generator or the like is a resin that is insoluble in water and soluble in an aqueous alkali solution.
Examples of the alkali-soluble resin used together with the acid generator and the like include novolak resin, hydrogenated novolak resin, acetone-pyrogallol resin, poly-o-hydroxystyrene, poly-m-hydroxystyrene, poly-p
-Hydroxystyrene, hydrogenated polyhydroxystyrene, halogen- or alkyl-substituted polyhydroxystyrene, hydroxystyrene-N-substituted maleimide copolymer, o / p- and m / p-hydroxystyrene copolymer, for the hydroxyl group of polyhydroxystyrene Some O-
Alkyl compounds (for example, 5 to 30 mol% of O-methyl compound, O- (1-methoxy) ethyl compound, O- (1-ethoxy) ethyl compound, O-2-tetrahydropyranyl compound, O- (t- Butoxycarbonyl) methylated product) or O-acylated product (for example, 5 to 30 mol% o-
Acetylated product, O- (t-butoxy) carbonylated product, etc.), styrene-maleic anhydride copolymer, styrene-
Examples thereof include, but are not limited to, hydroxystyrene copolymers, α-methylstyrene-hydroxystyrene copolymers, carboxyl group-containing methacrylic resins and derivatives thereof. Among the above alkali-soluble resins, particularly preferred alkali-soluble resins are novolak resins and poly-o-hydroxystyrene, poly-
m-hydroxystyrene, poly-p-hydroxystyrene and copolymers thereof, alkyl-substituted polyhydroxystyrene, partially O-alkylated or O-acylated product of polyhydroxystyrene, styrene-hydroxystyrene copolymer, α -Methylstyrene-hydroxystyrene copolymer.

The above-mentioned novolak resin is obtained by subjecting a predetermined monomer as a main component to addition condensation with an aldehyde in the presence of an acidic catalyst. As the predetermined monomer, phenol, m-cresol, p-cresol,
Cresols such as o-cresol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol,
Xylenols such as 2,3-xylenol, alkylphenols such as m-ethylphenol, p-ethylphenol, o-ethylphenol, pt-butylphenol, p-octylphenol, 2,3,5-trimethylphenol, p -Methoxyphenol, m-methoxyphenol, 3,5-dimethoxyphenol, 2-methoxy-4-methylphenol, m-ethoxyphenol, p-ethoxyphenol, m-propoxyphenol, p-propoxyphenol, m-butoxyphenol, Alkoxyphenols such as p-butoxyphenol, bisalkylphenols such as 2-methyl-4-isopropylphenol, m-chlorophenol, p-chlorophenol, o-chlorophenol, dihydroxybiphenyl, bisphenol Nord A, phenylphenol,
Hydroxy aromatic compounds such as resorcinol and naphthol can be used alone or in combination of two or more, but are not limited thereto.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-
Phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o -Methylbenzaldehyde, m-methylbenzaldehyde,
p-Methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde, furfural, chloroacetaldehyde, and their acetal compounds, such as chloroacetaldehyde diethyl acetal, among which formaldehyde is used Is preferred. These aldehydes are used alone or in combination of two or more. As the acidic catalyst, hydrochloric acid, sulfuric acid, formic acid, acetic acid, oxalic acid and the like can be used.

The weight-average molecular weight of the novolak resin thus obtained is preferably in the range of 1,000 to 30,000. If it is less than 1,000, the film loss of the irradiated portion after development is large, and if it exceeds 30,000, the development speed is reduced. Particularly preferred are 2,000 to 20,000.
00 range. Further, the weight average molecular weight of the polyhydroxystyrene other than the novolak resin, its derivative, and the copolymer is 2,000 or more, preferably 2,000 to 2,000.
It is 30,000, more preferably 2,000 to 20,000. Here, the weight average molecular weight is defined as a value in terms of polystyrene by gel permeation chromatography. The alkali dissolution rate of the alkali-soluble resin is 0.
Those measured at 23 ° C. with 261N tetramethylammonium hydroxide (TMAH) at 20 ° C./sec or more are preferred. Particularly preferably, it is 200 ° / sec or more. These alkali-soluble resins in the present invention may be used alone or in combination of two or more. The amount of the alkali-soluble resin used is usually 30 to 9 based on the total weight of the resist composition (excluding the solvent).
0% by weight, preferably 50 to 80% by weight.

(B) Acid Generator The acid generator used in the present invention is a compound which generates an acid upon irradiation with an electron beam or X-ray. First, the acid generators represented by the general formulas (I) to (III), which are preferred acid generators in the present invention, will be described. R _{1 to} R ₃₇ in the general formulas (I) to (III) may be the same or different, and each is independently an alkyl group, an alkoxy group, a hydroxyl group, a halogen atom, or
Is a group that can be represented by -S-R _38. The alkyl group represented by R _{1 to} R ₃₇ may be linear or branched,
It may be annular. As a linear or branched alkyl group,
For example, a C1-C4 alkyl group, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, can be mentioned. Examples of the cyclic alkyl group include an alkyl group having 3 to 8 carbon atoms such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group. The alkoxy group represented by R _{1 to} R ₃₇ may be linear, branched, or a cyclic alkoxy group. Examples of the linear or branched alkoxy group include those having 1 to 8 carbon atoms such as a methoxy group,
Ethoxy, hydroxyethoxy, propoxy, n
-Butoxy group, isobutoxy group, sec-butoxy group,
Examples thereof include a t-butoxy group and an octyloxy group. Examples of the cyclic alkoxy group include a cyclopentyloxy group and a cyclohexyloxy group.

The halogen atom represented by R _{1 to} R ₃₇ includes
Examples include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R ₃₈ in -S-R ₃₈ in which R ₁ to R ₃₇ represents the
It is an alkyl group or an aryl group. The scope of the alkyl group R ₃₈ is represented can also include any example in the alkyl groups already listed as an alkyl group represented by R ₁ to R _37. The aryl group represented by R ₃₈ is a phenyl group,
Examples thereof include aryl groups having 6 to 14 carbon atoms, such as a tolyl group, a methoxyphenyl group, and a naphthyl group. R ₁
To R ₃₈ is an alkyl group represented below, to aryl groups are both bonded to a substituent in a part of the groups may have to increase the number of carbon atoms, may not have a substituent. The substituent which may be further bonded preferably has 1 carbon atom.
Examples thereof include an alkoxy group having 4 to 4, an aryl group having 6 to 10 carbon atoms, and an alkenyl group having 2 to 6 carbon atoms, and also include a cyano group, a hydroxy group, a carboxy group, an alkoxycarbonyl group, and a nitro group. be able to. In addition, a halogen atom may be used. For example, a fluorine atom,
A chlorine atom and an iodine atom can be exemplified.

The groups represented by R _{1 to} R ₁₅ in the general formula (I) are
Two or more of them may combine to form a ring. The ring may be formed by directly bonding the terminals of the groups represented by R _{1 to} R ₁₅ . They may be indirectly linked via one or more elements selected from carbon, oxygen, sulfur and nitrogen to form a ring. The ring structure formed by combining two or more of R _{1 to} R ₁₅ is the same as the ring structure found in a furan ring, dihydrofuran ring, pyran ring, trihydropyran ring, thiophene ring, pyrrole ring, and the like. Can be mentioned. R _{16 to} R in the general formula (II)
_{The same} can be said for ₂₇ . Two or more may be directly or indirectly linked to form a ring. The same applies to R _{28 to} R ₃₇ in the general formula (III).
In the general formulas (I) to (III), X ⁻ represents an anion of an organic sulfonic acid. The organic sulfonic acid is an organic sulfonic acid selected from benzenesulfonic acid, naphthalenesulfonic acid, or anthracenesulfonic acid, and part or all of the hydrogen atoms are substituted with fluorine atoms, or It is preferable that a part or the whole is substituted with an organic group substituted with a fluorine atom. Examples of the organic group substituted with a fluorine atom include, for example, an alkyl group, an alkoxyl group, an acyl group, an acyloxyl group, a sulfonyl group, a sulfonyloxy group, a sulfonylamino group, an aryl group, an aralkyl group, and an alkoxycarbonyl group. it can.

The alkyl group substituted by a fluorine atom is a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms and substituted by at least one fluorine atom, preferably 25 or less. Groups such as trifluoromethyl, pentafluoroethyl, 2,2,2
-Trifluoroethyl, heptafluoropropyl, heptafluoroisopropyl, perfluorobutyl, perfluorooctyl, perfluorododecyl, perfluorocyclohexyl and the like. Among them, a perfluoroalkyl group having 1 to 4 carbon atoms, all of which is substituted by fluorine, is preferable. The alkoxyl group substituted by a fluorine atom is a straight-chain, branched or cyclic alkoxyl group having 1 to 12 carbon atoms and substituted by at least one fluorine atom, preferably 25 or less fluorine atoms. Preferable examples include a trifluoromethoxy group, a pentafluoroethoxy group, a heptafluoroisopropyloxy group, a perfluorobutoxy group, a perfluorooctyloxy group, a perfluorododecyloxy group, and a perfluorocyclohexyloxy group. Among them, a perfluoroalkoxy group having 1 to 4 carbon atoms, all of which is substituted by fluorine, is preferable. An acyl group substituted with a fluorine atom has 2 carbon atoms.
Those which are substituted with 1 to 23 fluorine atoms by 1 to 12 are preferred. Specific examples include a trifluoroacetyl group, a fluoroacetyl group, a pentafluoropropionyl group, and a pentafluorobenzoyl group.

An acyloxy group substituted by a fluorine atom is
Those having 2 to 12 carbon atoms and substituted by 1 to 23 fluorine atoms are preferred. Specific examples include a trifluoroacetoxy group, a fluoroacetoxy group, a pentafluoropropionyloxy group, and a pentafluorobenzoyloxy group. As the sulfonyl group substituted with a fluorine atom, those having 1 to 12 carbon atoms and substituted with 1 to 25 fluorine atoms are preferable. Specific examples include a trifluoromethanesulfonyl group, a pentafluoroethanesulfonyl group, a perfluorobutanesulfonyl group, a perfluorooctanesulfonyl group, a pentafluorobenzenesulfonyl group, and a 4-trifluoromethylbenzenesulfonyl group. As the sulfonyloxy group substituted with a fluorine atom, those substituted with a fluorine atom having 1 to 12 or 1 to 25 carbon atoms are preferable. Specific examples include a trifluoromethanesulfonyloxy group, a perfluorobutanesulfonyloxy group, and a 4-trifluoromethylbenzenesulfonyloxy group. A sulfonylamino group substituted by a fluorine atom has 1 carbon atom.
~ 12, preferably substituted with 1 to 25 fluorine atoms. Specific examples include a trifluoromethanesulfonylamino group, a perfluorobutanesulfonylamino group, a perfluorooctanesulfonylamino group, and a pentafluorobenzenesulfonylamino group.

The aryl group substituted with a fluorine atom is preferably an aryl group having 6 to 14 carbon atoms and substituted with 1 to 9 fluorine atoms. Specific examples include a pentafluorophenyl group, a 4-trifluoromethylphenyl group, a heptafluoronaphthyl group, a nonafluoroanthranyl group, a 4-fluorophenyl group, and a 2,4-difluorophenyl group. The aralkyl group substituted with a fluorine atom preferably has 7 to 10 carbon atoms and is substituted with 1 to 15 fluorine atoms. Specific examples include a pentafluorophenylmethyl group, a pentafluorophenylethyl group, a perfluorobenzyl group, a perfluorophenethyl group, and the like. The alkoxycarbonyl group substituted with a fluorine atom has 2 to 13 carbon atoms,
Those substituted with 25 fluorine atoms are preferred.
Specific examples include a trifluoromethoxycarbonyl group, a pentafluoroethoxycarbonyl group, a pentafluorophenoxycarbonyl group, a perfluorobutoxycarbonyl group, and a perfluorooctyloxycarbonyl group.

Among such anions, the most preferred X ^- is a fluorine-substituted benzenesulfonate anion,
Among them, pentafluorobenzenesulfonic acid anion is particularly preferred. Further, the benzene sulfonic acid, naphthalene sulfonic acid, or anthracene sulfonic acid having the fluorine-containing substituent further has a linear, branched or cyclic alkoxy group, an acyl group, an acyloxy group, a sulfonyl group,
It may be substituted with a sulfonyloxy group, a sulfonylamino group, an aryl group, an aralkyl group, an alkoxycarbonyl group (the number of carbon atoms is the same as described above), a halogen (excluding fluorine), a hydroxyl group, a nitro group and the like. Hereinafter, specific examples of the compounds represented by the general formulas (I) to (III) are shown, but the invention is not limited thereto.

[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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The compounds of the general formulas (I) and (II)
It can be synthesized by the following method. For example, an aryl Grignard reagent such as aryl magnesium bromide is reacted with phenylsulfoxide, and the resulting triarylsulfonium halide is subjected to salt exchange with the corresponding sulfonic acid. There is another way. For example, there is a method in which phenyl sulfoxide and an aromatic compound corresponding thereto are condensed and salt-exchanged using an acid catalyst such as methanesulfonic acid / diphosphorus pentoxide or aluminum chloride. Further, the diaryl iodonium salt and the diaryl sulfide can be synthesized by a method of condensation or salt exchange using a catalyst such as copper acetate. In any of the above methods, the phenylsulfoxide may have a substituent substituted on the benzene ring, or may not have such a substituent. The compound of the general formula (III) can be synthesized by reacting an aromatic compound with periodate. The content of the acid generator used in the present invention is suitably 0.1 to 20% by weight, preferably 0.5 to 10% by weight, and more preferably 0.5 to 20% by weight, based on the solid content of the whole negative resist composition. 1 to 7% by weight. When the acid generator contains, for example, a compound represented by any one of formulas (I) to (III), the content thereof is based on the solid content of the entire negative resist composition. 0.1-20% by weight is suitable, preferably 0.5-10% by weight, more preferably 1-7% by weight.

(Other acid generators) In the present invention, other than the compounds represented by the above general formulas (I) to (III), other compounds which decompose upon irradiation with an electron beam or X-ray to generate an acid. Compounds can also be used. In addition, the general formula (I)
To a compound represented by the general formula (III) and an electron beam or X
It may be used in combination with another compound which is decomposed by irradiation with a ray to generate an acid. In this case, the general formulas (I) to (II)
The ratio of the compound represented by I) to the other compound which generates an acid by being decomposed by irradiation with an electron beam or X-ray is 100/0 to 20/80, preferably 90/10 to 40 in a molar ratio.
/ 60, more preferably 80/20 to 50/50. Examples of such other acid generators include photoinitiators for photocationic polymerization, photoinitiators for photoradical polymerization, photodecolorants for dyes, photochromic agents, and electron beams used in microresist and the like. Alternatively, a compound which decomposes upon irradiation with X-ray to generate an acid and a mixture thereof can be appropriately selected and used. For example, onium salts such as diazonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts and arsonium salts, organic halogen compounds, organic metals / organic halides, acid generators having an o-nitrobenzyl-type protecting group, iminosulfonates And the like, and a disulfone compound which is decomposed to generate a sulfonic acid.

Further, a compound or a compound in which a group or a compound capable of generating an acid upon irradiation with an electron beam or X-ray is introduced into a main chain or a side chain of a polymer, for example, JP-A-63-26653
JP-A-55-164824, JP-A-62-692
No. 63, JP-A-63-146038, JP-A-63-1
No. 63452, JP-A-62-153853, JP-A-62-18553
Compounds described in 3-146029 and the like can be used. Further, the compounds capable of generating an acid described in U.S. Pat. No. 3,779,778 and EP 126,712 can also be used.

(C) Crosslinking agent used in the present invention In the present invention, a compound capable of crosslinking by an acid (hereinafter referred to as an acid crosslinking agent or simply a crosslinking agent, as appropriate) has a molecular weight of 2000 or less (preferably 1200 or less). , The lower limit is preferably 300), the molecule contains 3 to 10 (preferably 3 to 5) benzene rings, and has at least one hydroxymethyl group and at least one alkoxymethyl group. A phenol derivative in which a methyl group is concentrated on at least one of the benzene rings or is separated and bonded (crosslinking agent (C1))
Use The alkoxymethyl group bonded to the benzene ring preferably has 6 or less carbon atoms. Specifically, methoxymethyl, ethoxymethyl, n-propoxymethyl, i-propoxymethyl, n-butoxymethyl, i-butoxymethyl, sec-butoxymethyl and t-butoxymethyl are preferred. Furthermore, 2-
Alkoxy-substituted alkoxy groups such as methoxyethoxy and 2-methoxy-1-propoxy are also preferred. Among these phenol derivatives, particularly preferred ones are listed below.

[0031]

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[0032]

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[0033]

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[0034]

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[0035]

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(Wherein L ^{1 to} L ⁸ represent a hydroxymethyl group, a methoxymethyl group or an ethoxymethyl group, provided that each compound has at least one hydroxymethyl group)
And at least one methoxymethyl group or ethoxymethyl group. The crosslinking agent of the present invention is synthesized by partially alkoxymethylating a phenol derivative having a hydroxymethyl group as an intermediate. A phenol derivative having a hydroxymethyl group is a phenol compound having no corresponding hydroxymethyl group (L ¹ to L ^{1 in the} above formula).
A compound in which L ⁸ is a hydrogen atom) and formaldehyde in the presence of a base catalyst.
At this time, the reaction temperature is set at 60 to prevent resinification and gelation.
It is preferable to carry out at a temperature of not more than ° C. Specifically, Japanese Patent Application Laid-Open
Compounds can be synthesized by the methods described in JP-A-282067 and JP-A-7-64285. Partial alkoxymethylation can be obtained by reacting a phenol derivative having a corresponding hydroxymethyl group with an alcohol in the presence of an acid catalyst. At this time, the reaction is preferably performed at a reaction temperature of 100 ° C. or less in order to prevent resinification and gelation. Specifically, it can be synthesized by a method described in European Patent EP632003A1 or the like. The conversion of the intermediate from methylol groups to alkoxymethyl groups is 20 to 98% as a mixture, preferably 30 to 96%.
%, More preferably 50 to 95% (the above measured value by NMR). Further, the content of the compound in which all methylol groups are completely substituted with alkoxymethyl groups is from 20 to 9
6%, preferably 50-93%, more preferably 60%
９０90% (above HPLC measurement value). Such a phenol derivative having at least one hydroxymethyl group and at least one alkoxymethyl group and concentrated or bound to any benzene ring may be used alone or in combination of two or more. May be used in combination. The crosslinking agent (C1) is used in an amount of usually 3 to 70% by weight, preferably 5 to 50% by weight, based on the total solid content of the resist composition. If the addition amount is less than 3% by weight, the residual film ratio tends to decrease, and if it exceeds 70% by weight, the resolving power decreases, and the stability of the resist solution during storage tends to be unfavorable. is there.

Further, the negative resist composition of the present invention comprises:
Furthermore, it is a phenol derivative containing 3 to 10 (preferably 3 to 5) benzene ring atoms in the molecule, and has a molecular weight of 2
000 or less (preferably 1200 or less, and the lower limit is preferably 300), which does not include a hydroxymethyl group, has two or more alkoxymethyl groups in a molecule, and bonds them to at least one of benzene ring groups. (C2) a crosslinking agent that exhibits a crosslinking reaction by the action of an acid, and a phenol derivative containing 3 to 10 (preferably 3 to 5) benzene ring groups in the molecule, and a molecular weight of 2000 or less (preferably 1200 or less, The lower limit is preferably 300), and a hydroxymethyl group is not included in the molecule without an alkoxymethyl group.
(C3) a cross-linking agent which has at least one of them and is bonded to at least one of the benzene ring groups and which exhibits a cross-linking reaction by the action of an acid. When (C2) or / and (C3) a cross-linking agent is used in addition to the (C1) cross-linking agent, the total amount of the (C1) to (C3) cross-linking agents is 3 to 60% by weight in the total solid content of the resist composition. %, Preferably 5
It is 50% by weight, more preferably 7 to 30% by weight.
The content of the (C2) crosslinking agent is preferably from 51 to 97% by weight, more preferably from 60 to 95% by weight, based on the total amount of the (C1) to (C3) crosslinking agents. The content is preferably 2 to 40% by weight, more preferably 3 to 40% by weight.
-20% by weight.

In the present invention, in addition to the above phenol derivatives, other crosslinking agents (i), (i)
i) may be used in combination. The molar ratio of the total amount of the above-mentioned (C1) to (C3) cross-linking agents to other cross-linking agents that can be used in combination therewith is 100/0 to 20/80, preferably 90/90.
/ 10 to 40/60, more preferably 80/20 to 50
/ 50. (I) Compound having N-hydroxymethyl group, N-alkoxymethyl group, or N-acyloxymethyl group (ii) Epoxy compound These crosslinking agents will be described in detail below. (I) As a compound having an N-hydroxymethyl group, an N-alkoxymethyl group, or an N-acyloxymethyl group, European Patent Publication (hereinafter referred to as “EP-A”) No. 0,133,216; West German Patent No. 3,63
No. 4,671, No. 3,711,264, monomer and oligomer-melamine-formaldehyde condensate and urea-formaldehyde condensate, alkoxy disclosed in EP-A 0,212,482 Benzoguanamine-formaldehyde condensates disclosed in substituted compounds and the like can be mentioned. More preferred examples include, for example, at least two free N-hydroxymethyl groups,
A melamine-formaldehyde derivative having an -alkoxymethyl group or an N-acyloxymethyl group, among which an N-alkoxymethyl derivative is particularly preferred.

(Ii) Examples of the epoxy compound include monomer, dimer, oligomer, and polymer epoxy compounds containing one or more epoxy groups. For example, a reaction product of bisphenol A with epichlorohydrin, a reaction product of a low molecular weight phenol-formaldehyde resin with epichlorohydrin and the like can be mentioned. Other examples include epoxy resins described and used in U.S. Pat. No. 4,026,705 and British Patent 1,539,192. (C1)
When a cross-linking agent other than the cross-linking agent is used in combination, (C1) the total amount of the cross-linking agent including the cross-linking agent is 3 to 3
It is used in an amount of 70% by weight, preferably 5 to 60% by weight, more preferably 7 to 40% by weight.

(D) Organic Basic Compound Preferred organic basic compounds that can be used in the present invention are compounds that are more basic than phenol. Among them, a nitrogen-containing basic compound is preferable. Preferred chemical environments include the structures of the following formulas (A) to (E).

[0041]

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Here, R ²⁵⁰ , R ²⁵¹ and R ²⁵² may be the same or different and include a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, Represents 6 to 6 hydroxyalkyl groups or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, wherein R
²⁵¹ and R ²⁵² may combine with each other to form a ring. R
²⁵³ , R ²⁵⁴ , R ²⁵⁵ and R ²⁵⁶ may be the same or different and represent an alkyl group having 1 to 6 carbon atoms. Further preferred compounds are nitrogen-containing basic compounds having two or more nitrogen atoms having different chemical environments in one molecule, and particularly preferred are both substituted or unsubstituted amino groups and ring structures containing nitrogen atoms. Or a compound having an alkylamino group.

Preferred specific examples include substituted or unsubstituted guanidine, substituted or unsubstituted aminopyridine, substituted or unsubstituted aminoalkylpyridine, substituted or unsubstituted aminopyrrolidine, substituted or unsubstituted indazole, imidazole, Substituted or unsubstituted pyrazole, substituted or unsubstituted pyrazine, substituted or unsubstituted pyrimidine, substituted or unsubstituted purine, substituted or unsubstituted imidazoline, substituted or unsubstituted pyrazoline, substituted or unsubstituted piperazine, substituted Or, unsubstituted aminomorpholine, substituted or unsubstituted aminoalkylmorpholine and the like can be mentioned. Preferred substituents are an amino group, aminoalkyl group, alkylamino group, aminoaryl group, arylamino group, alkyl group, alkoxy group, acyl group, acyloxy group, aryl group, aryloxy group, nitro group, hydroxyl group, cyano group It is.

As particularly preferred compounds, guanidine,
1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, imidazole, 2-methylimidazole, 4-methylimidazole, N-methylimidazole, 2-phenylimidazole, 4,5-diphenylimidazole, , 4,5-triphenylimidazole, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine,
-(Aminomethyl) pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, -Aminoethylpyridine, 3-aminopyrrolidine, piperazine, N- (2
-Aminoethyl) piperazine, N- (2-aminoethyl) piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1- (2-amino Ethyl) pyrrolidine, pyrazole, 3-amino-5-methylpyrazole,
5-amino-3-methyl-1-p-tolylpyrazole,
Pyrazine, 2- (aminomethyl) -5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6
-Dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N- (2-aminoethyl) morpholine, and the like, but are not limited thereto. These nitrogen-containing basic compounds are used alone or in combination of two or more. The ratio of the acid generator and the organic basic compound used in the composition is (acid generator) /
(Organic basic compound) (molar ratio) = 2.5 to 300 is preferred. When the molar ratio is less than 2.5, the sensitivity becomes low and the resolving power may decrease. When the molar ratio exceeds 300, the thickness of the resist pattern increases over time until heat treatment after irradiation, and the resolving power may decrease. . (Acid generator) / (organic basic compound) (molar ratio) is preferably from 5.0 to 200, more preferably from 7.0 to 150.

(E) Mixed Solvent The negative resist composition of the present invention comprises, as component (E):
At least one of propylene glycol monoalkyl ether carboxylate (also referred to as a group a solvent)
And at least one of propylene glycol monoalkyl ether, alkyl lactate and alkyl alkoxypropionate (also referred to as solvent of group b) and / or γ-butyrolactone, ethylene carbonate and propylene carbonate (also referred to as solvent of group c). Contains mixed solvent. That is, as the component (E), a combination of a solvent of group a and a solvent of group b, a combination of a solvent of group a and a solvent of group c, a solvent of group a, a solvent of group b, and a solvent of group c Is used.

Preferred examples of the propylene glycol monoalkyl ether carboxylate include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether acetate, and propylene glycol monoethyl ether propionate.

Preferred examples of the propylene glycol monoalkyl ether include propylene glycol monomethyl ether and propylene glycol monoethyl ether. Preferred examples of the alkyl lactate include methyl lactate and ethyl lactate. Examples of the alkyl alkoxypropionate include ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate,
Preferred are ethyl 3-methoxypropionate and methyl 3-ethoxypropionate.

The weight ratio (a: b) of the solvent of group a to the solvent of group b is preferably 90:10 to 15:85,
The ratio is more preferably 80:20 to 20:80, and still more preferably 70:30 to 25:75. The weight ratio (a: c) of the solvent in the group a to the solvent in the group c is 99.
9: 0.1 to 75:25 is preferable, and 9 is more preferable.
9: 1 to 80:20, more preferably 97: 3 to
85:15.

When these three solvents are combined,
The weight ratio of the solvent in group c is 0.1 to
It is preferably 25% by weight, more preferably 1 to 20% by weight, and still more preferably 3 to 17% by weight. In the present invention, the solid content of the resist composition containing each of the above components is preferably dissolved in the mixed solvent at a solid concentration of 3 to 25% by weight, more preferably 5 to 22% by weight, and still more preferably 5 to 22% by weight. It is 7 to 20% by weight.

Preferred combinations of the mixed solvent in the present invention include propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether Propylene glycol monomethyl ether acetate +
Ethyl lactate Propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate Propylene glycol monomethyl ether acetate +
γ-butyrolactone propylene glycol monomethyl ether acetate +
Ethylene carbonate Propylene glycol monomethyl ether acetate +
Propylene carbonate Propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether + γ-butyrolactone Propylene glycol monomethyl ether acetate +
Ethyl lactate + γ-butyrolactone propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate + γ-butyrolactone propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether + ethylene carbonate Propylene glycol monomethyl ether acetate +
Ethyl lactate + ethylene carbonate propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate + ethylene carbonate propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether + propylene carbonate Propylene glycol monomethyl ether acetate +
Ethyl lactate + propylene carbonate propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate + propylene carbonate.

Particularly preferred solvent combinations include propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether + γ-butyrolactone Propylene glycol monomethyl ether acetate +
Ethyl lactate + γ-butyrolactone propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate + γ-butyrolactone propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether + ethylene carbonate Propylene glycol monomethyl ether acetate +
Ethyl lactate + ethylene carbonate propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate + ethylene carbonate propylene glycol monomethyl ether acetate +
Propylene glycol monomethyl ether + propylene carbonate Propylene glycol monomethyl ether acetate +
Ethyl lactate + propylene carbonate propylene glycol monomethyl ether acetate +
Ethyl 3-ethoxypropionate + propylene carbonate.

The mixed solvent used in the composition of the present invention includes:
A solvent other than the above-mentioned specific solvent may be contained as long as the effects of the present invention are not impaired. Such other solvents generally range up to 30% by weight, based on the total solvent. As such a solvent, for example, ethylene glycol monomethyl ether, ethylene glycol monoalkyl ethers such as ethylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoalkyl ether acetates such as ethylene glycol monoethyl ether acetate, 2
-Alkyl pyruvates such as heptanone, methyl pyruvate, ethyl pyruvate, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide, ethylene dichloride, cyclohexanone, cyclopentanone, methyl ethyl ketone, 2-methoxyethyl Examples include acetate, toluene, ethyl acetate, N, N-dimethylformamide, tetrahydrofuran and the like.

(F) Other Components Used in the Composition of the Present Invention The negative resist composition of the present invention may further contain a dye, a surfactant and the like, if necessary. (F) -1 Dyes Suitable dyes include oil dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 1
03, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-5
05 (all manufactured by Orient Chemical Industries, Ltd.), crystal violet (CI42555), methyl violet (CI42535), rhodamine B (CI45170)
B), malachite green (CI42000), methylene blue (CI52015) and the like.

(F) -2 Surfactants Surfactants can be added to the above solvents. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether, polyoxyethylene nonyl phenol ether and the like Sorbitan such as polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopal Te - DOO, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan tristearate, Eftop EF301, E
F303, EF352 (manufactured by Shin-Akita Chemical Co., Ltd.), Megafac F171, F173 (Dainippon Ink Co., Ltd.)
), Florad FC430, FC431 (manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, S
C104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.)
Fluorinated surfactants such as organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.) and acrylic or methacrylic acid (co) polymerized polyflow Nos. 7
5, No. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like. The amount of these surfactants is usually 2 parts by weight per 100 parts by weight of the solid content in the composition of the present invention.
It is at most 1 part by weight, preferably at most 1 part by weight. These surfactants may be added alone or in some combination.

The resist composition of the present invention preferably contains a fluorine-based and / or silicon-based surfactant. The resist composition of the present invention preferably contains one or more of a fluorine-based surfactant, a silicon-based surfactant, and a surfactant containing both a fluorine atom and a silicon atom. As these surfactants, for example, JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, JP-A-62-170950, JP-A-63-34540
No., JP-A-7-230165, JP-A-8-62834, JP-A-9-544
No. 32, JP-A-9-5988, U.S. Pat.
Nos. 5528981, 5296330, 5436098, 55561
No. 43, No. 5294511, No. 5824451, and the following commercially available surfactants can be used as they are. As a commercially available surfactant that can be used,
For example, F-top EF301, EF303, (Shin-Akita Chemical Co., Ltd.),
Florard FC430, 431 (manufactured by Sumitomo 3M Limited), Megafac F171, F173, F176, F189, R08 (manufactured by Dainippon Ink Co., Ltd.), Surflon S-382, SC101, 102, 103, 10
4, 105, 106 (manufactured by Asahi Glass Co., Ltd.) and Troisol S-366 (manufactured by Troy Chemical Co., Ltd.). Also, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used as a silicon-based surfactant. The amount of the fluorine-based and / or silicon-based surfactant is usually 0.001% by weight to 2% by weight, preferably 0.01% by weight to 1% by weight, based on the solid content in the composition of the present invention.
It is. These surfactants may be added alone or in some combination.

In the production of precision integrated circuit elements, the pattern formation step on the resist film is performed by forming the negative of the present invention on a substrate (eg, a transparent substrate such as a silicon / silicon dioxide cover, a glass substrate, an ITO substrate, etc.). A good resist pattern can be formed by applying a mold resist composition, then irradiating with an electron beam drawing apparatus, heating, developing, rinsing and drying. Examples of the developer for the negative resist composition of the present invention include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, inorganic alkalis such as aqueous ammonia, ethylamine, n-propylamine and the like. Secondary amines such as monoamines, diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, alcoholamines such as dimethylethanolamine and triethanolamine, tetramethylammonium hydroxide, tetraethyl Aqueous solutions of alkalis such as quaternary ammonium salts such as ammonium hydroxide and choline, and cyclic amines such as pyrrole and piperidine can be used. Further, an appropriate amount of an alcohol such as isopropyl alcohol or a surfactant such as a nonionic surfactant may be added to an aqueous solution of the above alkalis. Of these developers, quaternary ammonium salts are preferred, and tetramethylammonium hydroxide and choline are more preferred.

[0057]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the contents of the present invention are not limited thereto. 1. Example of synthesis of constituent materials (1) Acid generator 1) Synthesis of tetramethylammonium pentafluorobenzenesulfonate 25 g of pentafluorobenzenesulfonyl chloride was dissolved in 100 ml of methanol under ice-cooling, and 25% by weight of tetramethylammonium hydroxide was added thereto. 100 g of the aqueous solution was slowly added. After stirring at room temperature for 3 hours, a solution of tetramethylammonium pentafluorobenzenesulfonate was obtained. This solution was used for salt exchange with sulfonium salt and iodonium salt.

2) Synthesis of triphenylsulfonium pentafluorobenzenesulfonate 50 g of diphenylsulfoxide was dissolved in 800 ml of benzene, and 200 g of aluminum chloride was added thereto.
Refluxed for 4 hours. The reaction solution was slowly poured into 2 L of ice, and 400 ml of concentrated hydrochloric acid was added thereto, followed by heating at 70 ° C. for 10 minutes. This aqueous solution was washed with 500 ml of ethyl acetate, filtered, and then a solution prepared by dissolving 200 g of ammonium iodide in 400 ml of water was added. The precipitated powder was collected by filtration, washed with water, washed with ethyl acetate and dried to obtain 70 g of triphenylsulfonium iodide. Triphenylsulfonium iodide (30.5 g) was dissolved in methanol (1000 ml), and silver oxide (19.1 g) was added to the solution.
Stirred for hours. The solution was filtered, and an excess amount of a solution of tetramethylammonium pentafluorobenzenesulfonate was added thereto. The reaction solution was concentrated, dissolved in 500 ml of dichloromethane, and the solution was washed with a 5% by weight aqueous solution of tetramethylammonium hydroxide and water. The organic phase was dried over anhydrous sodium sulfate and concentrated to obtain triphenylsulfonium pentafluorobenzenesulfonate (I-1).

3) Synthesis of di (4-t-amylphenyl) iodonium pentafluorobenzenesulfonate 60 g of t-amylbenzene and 39.5 potassium iodate.
g, 81 g of acetic anhydride, and 170 ml of dichloromethane were mixed, and 66.8 g of concentrated sulfuric acid was slowly added dropwise thereto under ice cooling. After stirring for 2 hours under ice cooling, the mixture was stirred at room temperature for 10 hours. 500 ml of water was added to the reaction solution under ice-cooling, and the mixture was extracted with dichloromethane. The organic phase was washed with sodium hydrogen carbonate and water, and then concentrated to obtain di (4-t-amylphenyl) iodonium sulfate. This sulfate was added to a solution of an excess amount of tetramethylammonium pentafluorobenzenesulfonate. 500 ml of water was added to this solution, and this was extracted with dichloromethane. The organic phase was washed with a 5% by weight aqueous solution of tetramethylammonium hydroxide and water, and then concentrated to obtain di (4-t-amylphenyl).
Iodonium pentafluorobenzenesulfonate (III-
1) was obtained. Other compounds can be synthesized using the same method as described above.

(2) Crosslinking Agent Synthesis of Crosslinking Agent [HM-1] 1- [α-methyl-α- (4-hydroxyphenyl) ethyl] -4- [α, α-bis (4-hydroxyphenyl) ethyl 20 g of benzene (Honshu Chemical Industry Co., Ltd. T
risp-PA) was added to a 10% by weight aqueous potassium hydroxide solution, and the mixture was stirred and dissolved. Then, while stirring this solution,
60 ml of a 37% by weight aqueous solution of formalin was gradually added at room temperature over 1 hour. After stirring at room temperature for 6 hours, the mixture was thrown into a dilute sulfuric acid aqueous solution. The precipitate was filtered, washed sufficiently with water, and recrystallized from 30 ml of methanol to obtain 20 g of a white powder of a phenol derivative having a hydroxymethyl group [HM-1] having the following structure.

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Synthesis of Crosslinking Agent [HMM-1] 20 g of the phenol derivative having a hydroxymethyl group [HM-1] obtained in the above Synthesis Example was added to 1 liter of methanol, and the mixture was heated and stirred to dissolve. Next, 1 ml of concentrated sulfuric acid was added to this solution, and the mixture was heated under reflux for 6 hours. The reaction solution was cooled, and 2 g of potassium carbonate was added. After sufficiently concentrating this mixture, 300 ml of ethyl acetate was added. The solution was washed with water and concentrated to dryness to give a phenol derivative having a methoxymethyl group having the following structure [HMM-
18 g of a white solid of 1) was obtained. The ratio of all the methylol groups of the crosslinker [HM-1] converted to methoxymethyl groups was determined by liquid chromatography to be 70% (area ratio), and the methylol groups in the mixture determined by NMR And the ratio of methoxymethyl groups was 10:90.

[0063]

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Further, the following phenol derivatives were synthesized in the same manner.

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[0066]

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[0067]

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[0068]

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2. Examples [Examples and Comparative Examples] (1) Coating of resist A resist composition having the composition shown in Table 1 below was prepared using the compounds constituting the present invention and the comparative compounds selected from the above synthesis examples. Each resist solution was prepared by filtering through a 1 μm filter.

[0070]

[Table 1]

The abbreviations used in Table 1 indicate the following. <Resin> P-1: poly- (p-hydroxystyrene) Mw 10,000 Mw / Mn = 1.4 P-2: novolak resin / m-cresol / p-cresol = 45/55 (molar ratio) Mw 6,500

[0072]

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[0073]

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PMMHMM-1: fully methoxymethylated HMM-1

<Organic base> TPI: 2,4,5-triphenylimidazole <Organic solvent> S1: propylene glycol monomethyl ether acetate S2: propylene glycol monomethyl ether propionate S3: ethyl lactate S4: propylene glycol monomethyl ether S5: Ethyl ethoxypropionate S6: γ-butyrolactone S7: Ethylene carbonate S8: Propylene carbonate S9: Cyclohexanone <Surfactant> W-1: Troysol S-366 (manufactured by Troy Chemical Company)

(2) Evaluation of resist [Coating uniformity on substrate surface] The above prepared resist solution was applied on a 6-inch silicon wafer using a coating machine CDR-650 manufactured by Canon Inc. and applied to a vacuum suction hot plate. And dried at 110 ° C for 60 seconds to obtain a resist film having a thickness of 0.300 µm. The surface of the resist film was observed with an optical microscope to examine the occurrence of residual wetting and striation, but none of them was found. Further, the film thickness value of the resist is set to 1 c along a straight line passing through the center of the wafer by Alpha Step-100 (manufactured by TENVCOR).
Ten points were measured at m pitches. The variance of the measured value with respect to the target film thickness (the root mean square of the difference from the average) was used as an index of coating uniformity. [Development Defects] Each resist film was applied to a thickness of 0.5 μm on a 6-inch Bare Si substrate, and dried at 110 ° C. for 60 seconds on a vacuum suction hot plate. Next, 0.20 μm
Contact hole pattern (Hole duty ratio =
After irradiation with an electron beam lithography apparatus (acceleration voltage 50 eV) through a test mask of 1: 3), heating after irradiation was performed for 110 days.
C. for 90 seconds. 2.38% by weight TMAH
(Aqueous solution of tetramethylammonium hydroxide)
After paddle development for 0 second, the substrate was washed with pure water for 30 seconds and spin-dried. The number of development defects of the sample thus obtained was measured with a KLA-2112 machine manufactured by KLA Tencor Co., Ltd., and the obtained primary data value was defined as the number of development defects.
Table 2 shows the performance evaluation results.

[0077]

[Table 2]

[Explanation of Evaluation Results] From Table 2, it can be seen that the resist composition of the present invention has excellent coating uniformity on the substrate surface and significantly reduces the occurrence of defects during development.

[0079]

According to the present invention, it is possible to provide a chemically amplified negative resist composition for electron beams or X-rays, which has excellent coating uniformity on the substrate surface and reduces the occurrence of defects during development.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) H01L 21/027 H01L 21/30 502R F-term (Reference) 2H025 AA04 AA18 AB16 AC05 AC06 AD01 BE00 CB17 CB29 CB41 CB45 CC03 CC17 CC20 FA17 4H006 AA01 AA03 AB92 EA22

Claims (4)

[Claims] At least the following (A), (B) and (C)
A negative resist composition for electron beam or X-ray, comprising (1), (D) and (E). (A) an alkali-soluble resin (B) an acid generator (C1) a phenol derivative containing 3 to 10 benzene ring atoms in the molecule, a molecular weight of 2000 or less, and a hydroxymethyl group and an alkoxymethyl group in the molecule each having 1 (D) Organic basic compound (E) At least one of the solvents in the following group a: Seed and b below
Group A: mixed solvent containing at least one of the following Group c solvents: Group a: propylene glycol monoalkyl ether carboxylate Group b: propylene glycol monoalkyl ether, alkyl lactate and alkyl alkoxypropionate Group c: γ- Butyrolactone, ethylene carbonate and propylene carbonate 2. The following (C2) and / or (C3)
2. The negative resist composition for electron beams or X-rays according to claim 1, comprising: (C2) a phenol derivative containing 3 to 10 benzene ring groups in the molecule, having a molecular weight of 2,000 or less, containing no hydroxymethyl group, and having two or more alkoxymethyl groups in the molecule, and having at least one of them (C3) A phenol derivative containing 3 to 10 benzene ring atoms in the molecule, having a molecular weight of 2,000 or less and containing an alkoxymethyl group. Having two or more hydroxymethyl groups in the molecule and having at least one of them bonded to at least one benzene ring group, showing a crosslinking reaction by the action of an acid 3. The method according to claim 1, wherein the acid generator (B) has the following general formula (I):
The electron beam or X according to claim 1 or 2, wherein the compound is a compound represented by any one of the above (III).
Negative resist composition for lines. Embedded image [In the general formulas (I) to (III), R _{1 to} R ₃₇ each independently represent a hydrogen atom, an alkyl group, an alkoxyl group, a hydroxyl group, a halogen atom, or a group represented by —SR ₃₈ . R ₃₈ in -S-R ₃₈ represents an alkyl group or an aryl group. In the case of R _{1 to} R ₁₅ , two or more selected from them are directly bonded to each other at the terminal, or oxygen,
They may combine with each other via an element selected from sulfur and nitrogen to form a ring structure. In the case of R _{16 to} R ₂₇ , a ring structure may be similarly formed. In the case of R _{28 to} R ₃₇ , a ring structure may be similarly formed. X ^- represents an anion of an organic sulfonic acid. ] 4. In the acid generators of the general formulas (I) to (III), X ⁻ is an anion of an organic sulfonic acid selected from benzenesulfonic acid, naphthalenesulfonic acid or anthracenesulfonic acid, 4. The method according to claim 3, wherein part or all of the hydrogen atoms are substituted with fluorine atoms, or part or all of the hydrogen atoms are substituted with an organic group substituted with fluorine atoms. Negative resist composition for electron beam or X-ray.