JPH06130665A - Resist coating composition - Google Patents

Abstract

PURPOSE:To obtain a resist coating composition excellent in coating property, storage stability and pattern forming property which can be used for any radiation such as far UV rays, X rays and electron beams. CONSTITUTION:This resist coating compsn. is a positive or negative type resist containing the following compds. (1)-(4). (1) Alkali-soluble resin. (2) Radiation- sensitive acid producing agent. (3) Compd. which can be decomposed in the presence of acid to show such a property to decrease, to eliminate or to promote the controlling effect for solubility with alkali of the alkali soluble resin (1). Or, compd. which crosslinks the alkali soluble resin (1). (4) Solvent expressed by R<1>-CO-R<2>. R<1> and R<2> may be same or different and are hydrocarbon groups with the sum of carbon numbers 5 to 12, or R<1> and R<2> may be bonded and can form rings with carbon atoms bonded to R<1> or R<2>. This compsn. can be useful as a resist for the production of semiconductor devices for which further fine working technique is expected.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a resist coating composition. More specifically, it relates to a resist coating composition suitable for forming a resist film particularly useful for ultrafine processing.

[0002]

2. Description of the Related Art In the field of microfabrication represented by the manufacture of integrated circuits, miniaturization of the processing size in lithography has been further advanced in order to obtain a higher degree of integration of integrated circuits. There is a need for a technique capable of stably performing fine processing of 5 μm or less. Therefore, it is necessary to accurately form a pattern of 0.5 μm or less even in the resist used. However, in the conventional method using visible light (700 to 400 nm) or near ultraviolet light (400 to 300 nm),
It is extremely difficult to accurately form a pattern of 5 μm or less. Therefore, a lithography technique using shorter wavelength radiation (300 nm or less) has been studied.

Examples of such radiation include far-ultraviolet rays represented by a bright line spectrum of a mercury lamp (254 nm), KrF excimer laser (248 nm), X-rays represented by synchrotron radiation, and charged particles represented by electron beams. Lines can be mentioned, and various resists corresponding to these radiations have been proposed.

[0004] Of these, particular attention is given to a resist that causes a reaction that changes the solubility in a developing solution by the catalytic action of an acid produced by irradiation of radiation. This type of resist is usually used. It is called "chemically amplified resist".

When a resist is used in a manufacturing process of an integrated circuit, a resist solution prepared by dissolving each resist component such as a radiation sensitive component and a film forming component in a solvent (hereinafter referred to as "resist coating composition") is usually used. Is prepared and coated on a substrate to be processed by using a spin coater or a roll coater to form a resist film. Therefore, the coating property and storage stability of the resist coating composition are indispensable performances for stably performing advanced fine processing. Further, the resist film forms a pattern suitable for microfabrication by irradiating with radiation, but the shape of the pattern at this time has an important influence on the accuracy of microfabrication, and a rectangular shape is preferable. There is.

In a resist using a novolak resin and a naphthoquinonediazide-based photosensitizer, which has been used in conventional lithography using visible light, near-ultraviolet, etc., ethylcellosolve or methyl is used as a solvent when preparing a resist coating composition. It is known that the above performance can be satisfied by using a cellosolve-based compound. However, for the “chemically amplified resist”, when an ethyl cellosolve or a methyl cellosolve-based compound is used as a solvent when preparing a resist coating composition, there are problems in coating properties and storage stability. There is a problem that the formed pattern shape does not become a rectangle but becomes an overhang.

[0007]

An object of the present invention is to provide a novel resist coating composition. Another object of the present invention is to provide a resist coating composition suitable for use as a resist composition capable of stably performing fine processing, having excellent properties such as coating property and storage stability, and giving a good pattern shape. Especially. Further objects and advantages of the present invention will be apparent from the following description.

[0008]

According to the present invention, the above objects and advantages of the present invention are as follows: (1) an alkali-soluble resin (hereinafter referred to as "resin (A)"); and (2) feeling. Radioactive acid forming agent (3) having the property of controlling the alkali solubility of the alkali-soluble resin of (1), and being decomposed in the presence of an acid to control the alkali solubility of the alkali-soluble resin of (1) A compound (hereinafter, referred to as a “dissolution control agent”) that exhibits the property of reducing or eliminating the solvent or the property of promoting the alkali solubility of the alkali-soluble resin of (1), and (4) the following structural formula (i) R as a solvent. here ^{1 -CO-R 2 (i)} , R 1 and R ² are identical or different, or R ¹ and R ² or both the total number of carbon atoms of a hydrocarbon group comprising a 5 to 12 coupled to each other And then the charcoal they are bound to This is achieved by a positive resist coating composition (hereinafter, referred to as "first invention") containing a compound represented by the following which may form a ring together with an elementary atom.

According to the present invention, secondly, the above objects and advantages of the present invention include (1) a substituted methyl group, a 1-substituted ethyl group, a silyl group, a germyl group, an alkoxycarbonyl group and an acyl group. A resin (hereinafter referred to as "resin (B)") which is an alkali-insoluble or sparingly-soluble resin having at least one selected acid-dissociable group and which is alkali-soluble when the above-mentioned groups are acid-dissociated (2) Achieved by a positive resist coating composition (hereinafter referred to as "second invention"), which comprises a radioactive acid forming agent and (3) a compound represented by the above structural formula (i) as a solvent. To be done.

Furthermore, according to the present invention, thirdly, the above objects and advantages of the present invention are (3) in the presence of (1) resin (A), (2) radiation-sensitive acid forming agent, and (3) acid. A negative resist coating containing a compound (1) for crosslinking an alkali-soluble resin (hereinafter referred to as a "crosslinking agent"), and (4) a compound represented by the structural formula (i) as a solvent. By the composition (hereinafter referred to as “third invention”),
The same is achieved.

The resist coating composition of the present invention will be described below. First, each component will be described.

Resin (A) Resin (A) used in the first and third inventions
Has a property of being soluble in an alkali developing solution. Therefore, any resin may be used as long as it has a functional group having an affinity with the alkaline developer, for example, an acidic functional group such as a phenolic hydroxyl group or a carboxyl group. As a suitable resin (A), for example, the following formula (1)

[0013]

[Chemical 1]

A repeating unit represented by the following formula (2)

[0015]

[Chemical 2]

Here, the definition of R ⁰¹ is the same as in the above formula (1),

The repeating unit represented by the following formula (3)

[0018]

[Chemical 3]

The repeating unit represented by and the following formula (4)

[0020]

[Chemical 4]

Where R ⁰⁴ , R ⁰⁵ , R ⁰⁶ , R ⁰⁷ and R
⁰⁸ is the same or different and is a hydrogen atom or 1 to
Is an alkyl group of 4,

A resin containing at least one repeating unit of the repeating units represented by

The resin (A) in the present invention has the formula (1),
It may be composed only of the repeating unit represented by the formula (2), the formula (3) or the formula (4), or may have other repeating units. Examples of other repeating units here include maleic anhydride, fumaronitrile, acrylamide, acrylonitrile, vinylpyridine, vinylpyrrolidone, vinylimidazole, a repeating unit in which a double bond of a monomer containing a double bond such as vinylaniline is cleaved. Can be mentioned.

Formula (1), Formula (2), and Resin (A)
The content of the repeating units represented by the formulas (3) and (4) cannot be unconditionally determined by the other repeating units contained, but is usually 15 mol% or more, preferably 20 mol% or more. The molecular weight of the resin (A) of the present invention is the polystyrene-converted weight average molecular weight measured by gel permeation chromatography (hereinafter referred to as “Mw”).
Is preferably 1,000 to 150,000, and particularly preferably 3,000 to 100,000.

The resin (A) can be produced, for example, by polymerizing a corresponding vinyl monomer or by polycondensing phenols and aldehydes. Among these resins (A), the resin containing the repeating unit represented by the formula (1) or (4) has a hydrogenation rate of 70% or less, preferably 50%.
The hydrogenated product can be used as a hydrogenated product of 40% or less, more preferably 40% or less.

Resin (B) The resin (B) used in the second invention is a resin in which an acidic functional group of the above resin (A), for example, a hydrogen atom such as a phenolic hydroxyl group or a carboxyl group is substituted with a methyl group or 1-substitution. It is an alkali-insoluble or sparingly-soluble resin substituted with at least one acid-dissociable group (hereinafter referred to as "substituent B") selected from an ethyl group, a silyl group, a germyl group, an alkoxycarbonyl group and an acyl group. Here, the acid dissociable group refers to a group capable of dissociating in the presence of an acid.

Specific examples of the substituent B include methoxymethyl group, methylthiomethyl group, methoxyethoxymethyl group, tetrahydropyranyl group, tetrahydrofuranyl group, tetrahydrothiopyranyl group, tetrahydrothiofuranyl group and benzyloxymethyl group. , Phenacyl group, bromophenacyl group, methoxyphenacyl group, α-methylphenacyl group, cyclopropylmethyl group, cyclohexyl group, cyclopentyl group, benzyl group, triphenylmethyl group, diphenylmethyl group, bromobenzyl group, nitrobenzyl group, Substituted methyl group such as methoxybenzyl group and piperonyl group; 1-substituted ethyl group such as 1-methoxyethyl group, 1-ethoxyethyl group, isopropyl group, t-butyl group and 1,1-dimethylpropyl group; trimethylsilyl group, Triethyl Group, t-butyldimethylsilyl group, isopropyldimethylsilyl group, diphenyldimethylsilyl group and other silyl groups; trimethylgermyl group, triethylgermyl group, t-butyldimethylgermyl group, isopropyldimethylgermyl group, phenyldimethyl A germyl group such as a germyl group; an alkoxycarbonyl group such as a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group; and

Acetyl group, propionyl group, butyryl group, heptanoyl group, hexanoyl group, valeryl group, pivaloyl group, isovaleryl group, lauriloyl group, myristoyl group, palmitoyl group, stearoyl group, oxalyl group, malonyl group, succinyl group, glutaryl group. , Adipoyl group, piperoyl group, suberoyl group, azelaoil group, sebacoyl group, acryloyl group, propioloyl group, methacryl group, crotonoyl group, oleoyl group, maleoyl group, fumaroyl group, mesaconoyl group, camphoroyl group, benzoyl group, phthaloyl group, Isophthaloyl group, terephthaloyl group, naphthoyl group, toluoyl group,
An acyl group such as a hydroatropoyl group, an atropoyl group, a cinnamoyl group, a furoyl group, a thenoyl group, a nicotinoyl group, an isonicotinoyl group, a p-toluenesulfonyl group or a mesyl group can be mentioned.

Of these, a t-butyl group, a benzyl group, a tetrahydrofuranyl group, a tetrahydropyranyl group, a tetrahydrothiofuranyl group, a tetrahydrothiopyranyl group or a t-butoxycarbonyl group is preferable.

The introduction of the substituent B is carried out via the acidic functional group of the resin (A). Substituent B is preferably introduced in an amount of 15 to 100%, and more preferably 30 to 100%, based on all the acidic functional groups of resin (A). In addition, resin (B)
The molecular weight of Mw is preferably 1,000 to 150,000.
0, particularly preferably 3,000 to 100,000.

The resin (B) is insoluble or sparingly soluble in alkali. Alkali sparingly soluble means that a similar alkali is obtained by using a film of only the resin (B) in place of the resist film under suitable alkali development conditions when patterning the resist film formed using the second invention. When developing, it means a property that the resin (B) has a film thickness of 50% or more of the initial film thickness and remains after the operation.

Radiation-Sensitive Acid Forming Agent The compound used in the present invention which generates an acid in response to radiation, that is, the radiation-sensitive acid forming agent is, for example, an onium salt, a halogen-containing compound, a quinonediazide compound, a sulfone compound or a sulfonic acid. Examples thereof include compounds and nitrobenzyl compounds, and specifically, the compounds shown below can be exemplified.

Examples of the onium salt include iodonium salt, sulfonium salt, phosphonium salt, diazonium salt, ammonium salt and the like, and the following formula (5) is preferable.

[0034]

[Chemical 5]

A compound represented by the following formula (6)

[0036]

[Chemical 6]

Here, the definitions of R ¹ , R ² and X are the same as those in the above formula (5),

A compound represented by the following formula (7)

[0039]

[Chemical 7]

Here, the definitions of R ¹ , R ² , R ³ and X are the same as those in the above formula (5),

Examples thereof include compounds represented by:

As the halogen-containing compound, for example, a haloalkyl group-containing hydrocarbon compound, a haloalkyl group-containing heterocyclic compound and the like can be mentioned, preferably the following formula (8):

[0043]

[Chemical 8]

Here, R ⁸ is a trichloromethyl group, a phenyl group, a methoxyphenyl group, a naphthyl group or a methoxynaphthyl group,

A compound represented by the following formula (9)

[0046]

[Chemical 9]

Here, R ⁹ , R ¹⁰ and R ¹¹ are the same or different and each is a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a hydroxyl group.

Examples thereof include compounds represented by:

Examples of the quinonediazide compound include diazobenzoquinone compounds and diazonaphthoquinone compounds, and the following formula (10) is preferable.

[0050]

[Chemical 10]

A compound represented by the following formula (11)

[0052]

[Chemical 11]

A compound represented by the following formula (12)

[0054]

[Chemical 12]

A compound represented by the following formula (13)

[0056]

[Chemical 13]

Examples thereof include compounds represented by:

Examples of the sulfone compound include β-ketosulfone, β-sulfonylsulfone and the like, and the following formula (14) is preferable.

[0059]

[Chemical 14]

Examples thereof include compounds represented by:

Examples of the nitrobenzyl compound include a nitrobenzyl sulfonate compound and a dinitrobenzyl sulfonate compound, and the following formula (15) is preferable.

[0062]

[Chemical 15]

Examples thereof include compounds represented by:

Examples of the sulfonic acid compound include alkyl sulfonic acid ester, haloalkyl sulfonic acid ester, aryl sulfonic acid ester, imino sulfonate, and the like, and the following formula (16) is preferable.

[0065]

[Chemical 16]

Here, R ²⁵ and R ²⁶ are the same or different and each is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ²⁷ and R ²⁸ are the same or different and each is a hydrogen atom or 1 to 4 carbon atoms. 4 alkyl group or 6 to 20 carbon atoms
Is an aryl group of

A compound represented by the following formula (17)

[0068]

[Chemical 17]

Here, R ²⁹ is a hydrogen atom or a carbon number of 1 to
4 is an alkyl group, and R ³⁰ and R ³¹ are the same or different and are an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 20 carbon atoms, or R ³⁰ and R ³¹ are bonded to each other. And may form a ring together with the carbon atom to which they are bound,

And a compound represented by the following formula (18)

[0071]

[Chemical 18]

Here, Z is a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 4 carbon atoms or 7 to 2 carbon atoms.
Is an aralkyl group of 0,

Examples thereof include compounds represented by:

Of these, onium salts and quinonediazide compounds are particularly preferable. The amount of these radiation-sensitive acid forming agents blended is 100 for the above resin (A) or resin (B).
The amount is preferably 1 to 70 parts by weight, more preferably 3 to 50 parts by weight, and further preferably 3 to 2 parts by weight.
0 parts by weight. If it is less than 1 part by weight, it is difficult to obtain sufficient pattern forming ability, and if it exceeds 70 parts by weight, scum tends to occur.

Dissolution Control Agent In the first invention, a dissolution control agent is used. The dissolution control agent itself has an effect of controlling the alkali solubility of the alkali-soluble resin, and is decomposed in the presence of an acid, for example, hydrolyzed to reduce or eliminate the alkali solubility control effect on the alkali-soluble resin. And a property of promoting the alkali solubility of the resin (A).

Examples of the dissolution control agent include compounds in which a substituent capable of being liberated in the presence of an acid is introduced into an acidic functional group. Examples of the substituent include the substituent B described in the resin (B).

The dissolution control agent may be a low molecular weight compound,
It may be a polymer compound, for example, the following formula (19) and formula (2)
0), formula (21), formula (22) and formula (23)

[0078]

[Chemical 19]

[0079]

[Chemical 20]

[0080]

[Chemical 21]

[0081]

[Chemical formula 22]

[0082]

[Chemical formula 23]

Examples thereof include compounds represented by:

As the dissolution control agent, the resin (B) is further added.
Can be used to advantage. The compounding amount of the dissolution control agent is preferably 5 to 150 parts by weight, more preferably 5 to 100 parts by weight, based on 100 parts by weight of the resin (A) in the first invention.

Crosslinking Agent In the third invention, a crosslinking agent is used. The crosslinking agent is
It is a compound that crosslinks the resin (A) in the presence of an acid, for example, an acid generated by irradiation with radiation.

As the compound having the above-mentioned properties, an aromatic compound having a crosslinkable substituent can be preferably mentioned, for example, -C (R ³⁷ R ³⁸ ) -OR ^39.
An aromatic compound having a group (provided that R ³⁷ and R ^{38, which} may be the same or different, represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ³⁹ represents a hydrogen atom or a C 1 to 5 carbon atom). An alkyl group, an aralkyl group having 7 to 20 carbon atoms, a -NR ⁴⁰ R ⁴¹ group (provided that R ⁴⁰ and R ⁴¹ may be the same or different, and may contain an alkyl group having 1 to 4 carbon atoms or a hetero atom, or Number of non-contained atoms 3-8
Represents a cyclo ring), a —COR ⁴² group (provided that R ⁴² represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 14 carbon atoms),

An aromatic compound having --CO--R ⁴³ (provided that R ⁴³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), an aromatic compound having --CR ⁴⁴ = CR ⁴⁵ R ⁴⁶ (provided that R ⁴⁴ , R ⁴⁵ and R ⁴⁶ may be the same or different and each represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms).

Further, as a part of the specific examples of the crosslinkable substituent, for example, a glycidyl ether group, a glycidyl ester group, a glycidylamino group, a methoxymethyl group,
Ethoxymethyl group, benzyloxymethyl group, dimethylaminomethyl group, diethoxymethylamino group, morpholinomethyl group, acetoxymethyl group, benzoyloxymethyl group, formyl group, acetyl group, vinyl group, isopropenyl group, etc. .

As the aromatic compound having the above-mentioned substituent, for example, a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a bisphenol S type epoxy compound, a novolac type epoxy compound, a resole resin type epoxy compound, a polyhydroxystyrene type epoxy compound. , A methylol group-containing benzoguanamine compound,
Methylol group-containing urea compound, methylol group-containing phenol compound, methylol group-containing melamine compound, methylol group-containing phenol compound, alkyl ether group-containing melamine compound, alkyl ether group-containing benzoguanamine compound, alkyl ether group-containing urea compound,
Alkyl ether group-containing phenol compound, alkyl ether group-containing melamine compound, alkyl ether group-containing phenol compound, carboxymethyl group-containing melamine compound, carboxymethyl group-containing benzoguanamine compound, carboxymethyl group-containing urea compound, carboxymethyl group-containing phenol compound, carboxy Examples include methyl group-containing melamine compounds and carboxymethyl group-containing phenol compounds.

Of these, a methylol group-containing phenol compound, a methylol group-containing phenol compound, a methoxymethyl group-containing melamine compound, a methoxymethyl group-containing phenol compound and an acetoxymethyl group-containing phenol compound are preferable, and a methoxymethyl group-containing melamine compound is more preferable. Is. Specific examples of the compound include CYMEL300 and CYM manufactured by Mitsui Cyanamid.
EL301, CYMEL303, CYMEL305, etc. are mentioned.

As the cross-linking agent, those obtained by further modifying the resin (A) with the above-mentioned substituent capable of cross-linking reaction to impart the property as a cross-linking agent can be advantageously used. In that case, the introduction rate of the substituent is usually adjusted to 5 to 60%, preferably 10 to 50%, and more preferably 15 to 40% with respect to the total amount of the acidic functional groups of the resin (A). It
If it is less than 5%, it is difficult to cause a sufficient cross-linking reaction, so that the residual film rate is lowered, and the pattern is meandered or swollen.
On the other hand, when it exceeds 60%, the alkali solubility of the resin (A) is lowered, and the developability tends to be deteriorated.

The blending amount of the crosslinking agent is preferably 5 to 95 parts by weight, particularly preferably 15 to 85 parts by weight, and further preferably 20 to 75 parts by weight, based on 100 parts by weight of the resin (A). If it is less than 5 parts by weight, it is difficult to cause a sufficient cross-linking reaction and the residual film rate is lowered, and the pattern is meandered or swollen. On the other hand, if it exceeds 95 parts by weight, the scum content is large and the developability tends to deteriorate.

Solvent The compound represented by the above structural formula (i) is used. In the structural formula (i), R ¹ and R ² are the same or different and each is a hydrocarbon group having a total of 5 to 12 carbon atoms, or R ¹ and R ² are bonded to each other to form a bond. It may form a ring together with the carbon atom.

As the hydrocarbon group, for example, a linear, branched or cyclic alkyl group is preferable. Also, R ¹
And R ² together with the carbon atom to which they are bonded form a ring, the carbon number thereof is preferably 7 to 11, including the carbon to which R ¹ and R ² are bonded.

Specific examples of such a compound include cyclic compounds such as cyclohexanone, cycloheptanone, cyclooctanone, cyclononanone and sickdodecanone;

2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-octanone, 3-octanone, 4-octanone, 2-nonanone, 3-nonanone, 4-nonanone, 5-nonanone. , 2-
Decanone, 3-decanone, 4-decanone, 5-decanone, 2-methylpentan-3-one, 2-methylpentan-4-one, 3-methylpentan-2-one, 3-ethylpentan-2-one, 2-methylhexan-3-one, 2-methylhexan-4-one, 2-methylhexan-5-one, 3-methylhexan-2-one, 3-methylhexan-4-one, 3-methylhexan- 5-one, 3-ethylhexan-2-one, 3-ethylhexane-4-one, 4-ethylhexane-5-one,

2-Methylheptan-3-one, 2-methylheptan-4-one, 2-methylheptan-5-one, 2-methylheptan-6-one, 3-methylheptan-2-one, 3- Methylheptan-4-one, 3-methylheptan-5-one, 3-methylheptan-6-one, 4-methylheptan-2-one, 4-methylheptan-3-one, 3-ethylheptan-2- On, 3-ethylheptan-3-one, 5-ethylheptan-2-one, 4-ethylheptan-2-one, 4-ethylheptan-3-one, 4-propylheptan-2-one, 4-
Propylheptan-3-one,

Cyclopentyl methyl ketone, cyclopentyl ethyl ketone, cyclopentyl butyl ketone, cyclopentyl pentyl ketone, dicyclopentyl ketone,
Cyclohexyl methyl ketone, cyclohexyl ethyl ketone, cyclohexyl butyl ketone, cyclohexyl pentyl ketone, cyclohexyl cyclopentyl ketone,
Examples thereof include cyclohexyl hexyl ketone and dicyclohexyl ketone.

Of these, preferred compounds include cycloheptanone, cyclooctanone, 2-hexanone and 3-
Hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-octanone, 3-octanone, 4-octanone, 3-methylpentan-2-one, 3-ethylpentan-2-one, 3-methylhexane-2- On, 3-
Methylhexan-4-one, 3-methylhexane-5-
Examples thereof include on, 3-ethylhexan-2-one, 4-ethylhexan-2-one, cyclohexylmethylketone, cyclopentylethylketone, cyclohexylmethylketone, cyclohexylethylketone, and the like.

Further, particularly preferable compounds are cycloheptanone, 2-hexanone, 2-heptanone, 3-
Heptanone, 2-octanone, 3-octanone, 3-ethylpentan-2-one, 3-methylhexane-2-one, 3-ethylhexane-2-one, 4-ethylhexane-2-one, cyclopentylethylketone, Examples thereof include cyclohexyl methyl ketone.

The compounding amount of the compound represented by the structural formula (i) is usually 20 to 3,000 parts by weight, preferably 50 to 50 parts by weight with respect to 100 parts by weight of the resin (A) or the resin (B).
3,000 parts by weight, more preferably 100 to 2,000
Parts by weight. In the present invention, another solvent is added to the compound represented by the structural formula (i), and the total amount of the solvent, for example, 7
It is possible to mix in the range of less than 0% by weight, preferably less than 50% by weight, particularly preferably less than 30% by weight.

Here, other solvents include ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, benzyl ethyl ether and dihexyl ether; methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, benzyl acetate. , Ethyl benzoate, diethyl oxalate, diethyl maleate,
Esters such as ethylene carbonate, propylene carbonate and γ-butyrolactone; amides such as N-methylpyrrolidone, N, N-dimethylformamide and N, N-dimethylacetamide; alcohols such as 1-octanol, 1-nonanol and benzyl alcohol Kinds; Ethylene glyco-
Rumonomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether,
Diethylene glycol monoethyl ether and other diol monoethers and ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc. The ether ester of the diol can be mentioned.

If desired, the composition of the present invention may further contain various additives. Examples of such an additive include a surfactant for improving coating properties, striation and developability of a radiation irradiated portion after formation of a dry coating film. Examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, polyethylene glycol dilaurate, polyethylene glycol distearate, and commercial products. For example, F top EF301, EF303, E
F352 (manufactured by Shin-Akita Kasei Co., Ltd.), Megafax F1
71, F173 (manufactured by Dainippon Ink Co., Ltd.), Florard FC430, FC431 (manufactured by Sumitomo 3M Ltd.),
Asahi Guard AG710, Surflon S-382, SC
101, SC102, SC103, SC104, SC1
05, SC106 (manufactured by Asahi Glass Co., Ltd.), KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, No. 9
5 (manufactured by Kyoeisha Oil and Fat Chemical Co., Ltd.) and the like are used.

The content of the surfactant is usually 2 parts by weight or less per 100 parts by weight of the resin (A) or the resin (B). Examples of other additives include antihalation agents composed of azo compounds and amine compounds, adhesion promoters, storage stabilizers, and defoamers.

The composition of the present invention comprises the above-mentioned resin (A) or resin (B), a radiation-sensitive acid-forming agent and various additives to be added, if necessary in the above structural formula (i). It is prepared by dissolving it in a solvent containing the compound shown, and its viscosity is preferably 8 to 120 cp.

The composition of the present invention is applied onto a substrate such as a silicon wafer in the form of the above solution and dried to form a resist film. In this case, the coating on the substrate is carried out, for example, by preparing the composition of the present invention, filtering the composition, and then applying the composition by spin coating, flow coating, roll coating, or the like.

The formed resist film is partially irradiated with radiation to form a fine pattern. As the radiation to be used, for example, far ultraviolet rays such as excimer laser, X-rays such as synchrotron radiation, and charged particle beams such as electron beams are used depending on the type of the radiation-sensitive acid forming agent used. The irradiation conditions such as the radiation dose are appropriately determined according to the composition of the composition, the type of each additive, and the like.

In the present invention, in order to improve the apparent sensitivity of the resist and the like, it is preferable to carry out heating after irradiation with radiation. This heating condition varies depending on the composition of the composition, the type of each additive, etc., but is usually 30
-200 degreeC, Preferably it is 50-150 degreeC.

The developer used for the subsequent development is, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di- n-propylamine, triethylamine, methyldiethylamine, dimethylethano-
Ruamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo- [4.3] .0] -5-nonane or the like and an alkaline aqueous solution having a concentration of 0.1 to 5% by weight can be used.

Further, an alkaline aqueous solution prepared by appropriately adding a water-soluble organic solvent, for example, alcohols such as methanol and ethanol and a surfactant to the above developing solution can be used as the developing solution.

[0111]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.
In the examples, various characteristics were evaluated as follows. Mw Tosoh Corp. GPC column (2 G2000H _XL ,
G3000H _{XL (} 1 bottle, G4000 _XL 1 bottle) was used, and the flow rate was 1.0 ml / min, the elution solvent was tetrahydrofuran, and the column temperature was 40 ° C. The analysis conditions were gel permeation chromatography using monodisperse polystyrene as a standard.

Solubility When the resist components shown in Table 1 were dissolved, they were completely dissolved, there was no turbidity, and they were transparent. The resist coating composition was spin-coated on a silicon wafer and baked, and then the formed resist film was observed. The case where there was no coating unevenness, cloudiness and foreign matter and the surface was highly smooth was regarded as good. The sensitivity was defined as the radiation dose at which a line-and-space pattern with a sensitivity of 0.5 μm could be formed as designed. The unit is mJ / cm ² .

Using the pattern scanning electron microscope, the lower side length A and the upper side length B of the rectangular cross section of the resist pattern were measured, and 0.85 ≦ B / A ≦
When it was 1, the pattern shape was judged to be good.
However, in the case where the pattern shape has a skirt or an inverse taper shape, it was determined that the pattern was defective even if B / A was within the above range.

Storage stability The resist coating composition was heated and held at 45 ° C., and the period during which no foreign matter was generated and the sensitivity were observed. The occurrence of foreign matter was judged by observing the occurrence of turbidity or precipitation of the resist coating composition which was kept heated. In Table 1, the sensitivity in storage stability is the value of 3 months for the resist coating composition in which no foreign matter is generated, and the value on the day before the generation of foreign matter in the resist coating composition in which foreign matter is generated. .

Synthesis Example 1 30 g of polyhydroxystyrene was dissolved in tetrahydrofuran, 10 g of potassium t-butoxide was added, and 75 g of di-t-butyl-di-carbonate was added dropwise with stirring at 0 ° C. for 6 hours. Let After the reaction was completed, this solution was added dropwise to water, and the precipitated resin was dried in a vacuum drier.
Dry overnight at 0 ° C. The obtained resin has Mw = 3,0
It was a structure in which 63% of the hydrogen atoms of the phenolic hydroxyl group were substituted with t-butoxycarbonyl groups from the results of NMR measurement. This resin is called resin (A-1).

Synthesis Example 2 54 g of polyhydroxystyrene was dissolved in acetone,
27 g of t-butyl-α-bromoacetic acid, potassium carbonate 10
g and 9 g of potassium iodide were added, and the mixture was reacted for 7 hours with stirring under reflux. After the reaction was completed, this solution was dropped into water, and the precipitated resin was dried in a vacuum dryer at 50 ° C.
Dried overnight. The obtained resin has Mw = 18,000.
From the result of NMR measurement, the structure was such that 22% of the hydrogen atoms of the phenolic hydroxyl group were replaced with t-butylacetic acid residues. This resin is called resin (B-1).

Examples 1 to 6 and Comparative Examples 1 to 3 The solvents shown in Table 1 were mixed with the other components shown in Table 1, and the solubility was evaluated. The foreign matter was removed by filtration to obtain a resist coating composition. The obtained resist coating composition was spin-coated on a silicon wafer and then baked at 100 ° C. for 2 minutes, and the formed resist film was irradiated with radiation through a mask. Here, a KrF excimer laser irradiation device (MBK-400TL-N) manufactured by Admon Science Co. was used for irradiation. Then 110 ° C
Baking for 2 minutes at 60 ° C with a 2.38 wt% aqueous solution of tetramethylammonium hydroxide at 23 ° C.
The pattern was obtained by developing in, and then rinsing with water for 30 seconds. Regarding the resist coating composition, these were heated and held, and the storage stability was examined. The obtained results are shown in Table 1.

[0118]

[Table 1]

[0119]

EFFECT OF THE INVENTION The resist coating composition of the present invention is suitable as a resist coating composition capable of stably performing fine processing and having excellent properties such as coating property, storage stability and pattern shape. Further, since the resist coating composition of the present invention can cope with radiation such as deep ultraviolet rays such as excimer laser, X-rays such as synchrotron radiation, and charged particle beams such as electron beam, further miniaturization is expected in the future. It can be advantageously used as a resist for manufacturing semiconductor devices.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G03F 7/039 501 H01L 21/027

Claims (3)

[Claims] 1. A property of controlling (1) an alkali-soluble resin, (2) a radiation-sensitive acid forming agent, (3) an alkali-soluble resin of (1) an alkali-soluble resin, and the presence of an acid. A compound which is decomposed to exhibit the property of reducing or eliminating the alkali solubility controlling effect on the alkali-soluble resin of (1) or the property of promoting the alkali solubility of the alkali-soluble resin of (1), and (4) as a solvent Structural formula (i) R ¹ —CO—R ² (i) Here, R ¹ and R ² are the same or different and are hydrocarbon groups in which the total carbon number of both is 5 to 12, or R ¹ And R ² may be bonded to each other to form a ring together with the carbon atom to which they are bonded, the positive resist coating composition being characterized by containing: 2. An alkali-insoluble or sparingly soluble resin having at least one acid-dissociable group selected from (1) a substituted methyl group, a 1-substituted ethyl group, a silyl group, a germyl group, an alkoxycarbonyl group and an acyl group. A resin which is alkali-soluble when the above groups are acid-dissociated, (2)
A positive resist coating composition comprising a radiation-sensitive acid forming agent and (3) a compound represented by the structural formula (i) as a solvent. 3. The above structure as (1) an alkali-soluble resin, (2) a radiation-sensitive acid forming agent, (3) a compound which crosslinks the alkali-soluble resin of (1) in the presence of an acid, and (4) a solvent. A negative resist coating composition comprising a compound represented by formula (i).