JPH05197151A - Radiation-sensitive resin composition - Google Patents

Abstract

PURPOSE:To make it possible to stably perform fine machining and improve sensitivity, resolution, dry etching resistance, development property, film residual property, adhesiveness, and heat resistance by containing a polymer having a specific repeated unit and a radiation-sensitive agent. CONSTITUTION:A polymer having a repeated unit expressed by the formula I and/or the formula II and a radiation-sensitive agent are contained. In the formula I, Ar indicates a 2 to 8-valent aromatic ring, X indicates oxygen atom, sulfur atom, or-NR<2>-, where R<2> indicates hydrogen atom, alkyl atom, or aryl group, R<1> indicates alkyl group, Y indicates hydrogen atom or substituent releasable under the existence of acid, and (m), (n) indicate integers of 0-3. In the formula II, Ar, X, Y, R<1>, (m), and (n) have the same groups and integers as those shown in the formula I, and (p) is an integer of 0-2. A photo-acid generating agent generating acid via the irradiation with radioactive rays or a photo- crosslinking agent cross-linking a polymer is preferable for the radiation- sensitive agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a radiation-sensitive resin composition. More specifically, the present invention relates to a radiation-sensitive resin composition suitable as a resist useful for ultrafine processing using radiation such as far ultraviolet rays such as excimer laser.

[0002]

2. Description of the Related Art In the field of microfabrication represented by integrated circuit manufacturing, in order to obtain a higher degree of integration of integrated circuits, the processing size in lithography has been further miniaturized. There is a need for a technique capable of stably performing fine processing of 5 μm or less. Therefore, even in the resist used for fine processing,
It is necessary to accurately form a pattern of 0.5 μm or less, but in the conventional method using visible light (700 to 400 nm) or near ultraviolet (400 to 300 nm), a fine pattern of 0.5 μm or less can be accurately formed. It is extremely difficult to form. Therefore, the wavelength is short (300
Lithography using radiation is being investigated.

Examples of such radiation include a far-ultraviolet ray represented by a bright line spectrum of a mercury lamp (254 nm), a KrF excimer laser (248 nm), X-rays, charged particle beams, and the like. Lithography using an excimer laser is receiving particular attention. Therefore, even for resists used for lithography, the excimer laser can provide
High sensitivity for fine patterns of 5 μm or less, developability (no scum and residual image at development), residual film property (no film loss at development), adhesive property (resist pattern does not peel off at development), heat resistance ( There is a need for a resist excellent in that the resist pattern does not change due to heat). Further, with the miniaturization of integrated circuits, the dry etching process is progressing, and the dry etching resistance of the resist is an important performance requirement.

[0004]

An object of the present invention is to provide a novel radiation sensitive resin composition. Another object of the present invention is to provide a resist capable of stably performing fine processing, having high sensitivity, high resolution, and excellent performance such as dry etching resistance, developability, residual film property, adhesiveness, and heat resistance. To provide a radiation-sensitive resin composition suitable as
Further objects and advantages of the present invention will be apparent from the following description.

[0005]

According to the present invention, the above objects and advantages of the present invention are (A) the following formula (1):

[0006]

[Chemical 3]

And / or the following formula (2)

[0008]

[Chemical 4]

This is achieved by a radiation-sensitive resin composition comprising a polymer having a repeating unit represented by and (B) a radiation-sensitive agent.

The polymer as the component (A) used in the present invention (hereinafter referred to as "polymer (A)") contains the repeating unit represented by the above formula (1) and / or (2). ..

2 to 2 of Ar in the above formula (1) or (2)
Preferred examples of the octavalent aromatic ring include the following formulas

[0012]

[Chemical 5]

And the like.

Examples of the alkyl group represented by R ¹ in the above formula (1) or (2) include a methyl group, an ethyl group and n-.
Examples thereof include propyl group, isopropyl group, n-butyl group, t-butyl group and the like. A methyl group is preferred.

Examples of the aryl group for R ² in the above formula (1) or (2) include phenyl group, naphthyl group,
Examples thereof include anthracene group and pyrene group. Preferred is a phenyl group or a naphthyl group. Examples of the alkyl group for R ² are the same as those for R ¹ .

Specific examples of the substituent capable of being liberated in the presence of an acid in Y in the above formula (1) (hereinafter referred to as "Z group") include a substituted methyl group, a 1-substituted ethyl group and a silyl group. , A germyl group or an alkoxycarbonyl group.

Here, examples of the substituted methyl group include a methoxymethyl group, a methylthiomethyl group, a methoxyethoxymethyl group, a tetrahydropyranyl group, a tetrahydrothiopyranyl group, a tetrahydrofuranyl group, a tetrahydrothiofuranyl group, and a benzyloxymethyl group. Group, phenacyl group, bromophenacyl group, methoxyphenacyl group, α-
Methylphenacyl group, cyclopropylmethyl group, cyclopentyl group, cyclohexyl group, benzyl group, triphenylmethyl group, diphenylmethyl group, bromobenzyl group, nitrobenzyl group, methoxybenzyl group, piperonyl group, etc.

As the 1-substituted ethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, isopropyl group, t-
A butyl group, a 1,1-dimethylpropyl group, etc., a silyl group such as a trimethylsilyl group, a triethylsilyl group,
t-butyldimethylsilyl group, isopropyldimethylsilyl group, phenyldimethylsilyl group, etc.

The germyl group is a trimethylgermyl group, a triethylgermyl group, a t-butyldimethylgermyl group, an isopropyldimethylgermyl group, a phenyldimethylgermyl group, and the like, and the alkoxycarbonyl group is a methoxycarbonyl group, an ethoxycarbonyl group. Group, t-
Butoxy carbonyl group etc. can be mentioned.

The molecular weight of the polymer (A) is the weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography) (hereinafter referred to as "Mw").
The value of is preferably 1,000 to 30,000, more preferably 2,000 to 20,000. Mw is 1,000
If it is less than 30,000, heat resistance tends to decrease, and if it exceeds 30,000, application tends to be difficult.

As a method for producing the polymer (A) of the present invention, for example, an aromatic compound represented by the following formula (3) (R ¹ ) _m -Ar- (XY) _n ... (3) and 2 It is obtained by polycondensing aldehydes including -oxoacetate acid (CHO-COOH). R ¹ in the above formula (3),
m, Ar, X, Y and n are the same as the groups and integers shown in the above formula (1).

Preferred compounds represented by the formula (3) are, for example, benzene, toluene, naphthalene,
Aromatic hydrocarbons such as pyrene and durene; phenols
o-cresol, m-cresol, p-cresol,
2,3-xylenol, 2,4-xylenol, 2,5-
Xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,4-trimethylphenol, 2,3,5-trimethylphenol, resorcinol, 2-methylresorcinol, hydroquinone, 2-methylhydroquinone, catechol, pyrogallol, Examples thereof include phenol derivatives such as phloroglicinol; hydroxybenzoic acid derivatives such as hydroxybenzoic acid, dihydroxybenzoic acid and trihydroxybenzoic acid; and aromatic amine derivatives such as aniline, toluidine, and phenylenediamine.
The compound represented by the above formula (3) may be a single compound or a mixture of two or more compounds.

The aldehydes used in the present invention contain 2-oxoacetic acid. Examples of aldehydes other than 2-oxoacetic acid include formaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, and the like. p-hydroxybenzaldehyde, o-chlorobenzaldehyde, m
-Chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, p-ethylbenzaldehyde,
Examples thereof include pn-butylbenzaldehyde and furfural, and acetaldehyde and formaldehyde can be preferably used.

As the aldehyde used in the present invention, 2-oxoacetic acid may be used alone or in combination with the above-mentioned other aldehydes. The use ratio of 2-oxoacetic acid and other aldehydes (2-oxoacetic acid / other aldehydes) is usually 100/0 to 30/70 (molar ratio), preferably 95/5 to 30 /. 70 (molar ratio). The amount of the aldehyde used is preferably 0.1 to 3 mol, and more preferably 0.3 to 1.5 mol, based on 1 mol of the compound represented by the formula (3).

The catalyst used in the polycondensation of the compound represented by the formula (3) with aldehydes is hydrochloric acid, nitric acid,
Examples thereof include acidic catalysts composed of inorganic acids such as sulfuric acid and organic acids such as formic acid, oxalic acid, p-toluenesulfonic acid and acetic acid, or alkaline catalysts such as sodium hydroxide and potassium hydroxide.

In the polycondensation, the reaction medium is not particularly limited, but water is used, for example. When the compound represented by the formula (3) used for polycondensation does not dissolve in an aqueous solution and becomes heterogeneous from the initial stage of the reaction, a hydrophilic solvent can be used as a reaction medium. Examples of these hydrophilic solvents include alcohols such as methanol, ethanol, propanol and butanol; cyclic ethers such as tetrahydrofuran and dioxane. The amount of these reaction media used is usually 20 to 1,000 parts by weight per 100 parts by weight of the reaction raw material.

The polycondensation temperature can be appropriately adjusted depending on the reactivity of the reaction raw materials, but is usually 10 to 200.
C., preferably 70 to 150.degree. As the polycondensation method, a method of charging the compound represented by the formula (3), the aldehydes and the catalyst all at once, the compound represented by the formula (3), the aldehydes and / or the catalyst and the like as the reaction progresses Examples thereof include a method of adding, a method of adding an aldehyde and / or a catalyst after obtaining a low molecular weight compound having a repeating unit represented by the formula (1), and the like.

After completion of the polycondensation, in general, in order to remove the unreacted raw materials, the catalyst and the reaction solvent present in the system, the internal temperature is generally raised to 130 ° C to 230 ° C, and the pressure is reduced, for example, to 20 ° C. After the volatile matter is distilled off at about 50 mmHg, the polymer is recovered. When the polymer is precipitated, it can be recovered by separating the precipitate.

In Y in the above formula (1), the polymer (A) having a Z group can be obtained, for example, by subjecting the polymer obtained above and a compound having a Z group to a condensation reaction under an acid catalyst. You can The polymer (A) containing the repeating unit represented by the formula (2) is obtained by cyclizing the XY group and the COOY group in the polymer containing the repeating unit represented by the formula (1). You can

The radiation sensitive agent which is the component (B) is a compound which generates an acid upon irradiation with radiation (hereinafter referred to as "photoacid generator") or a compound which decomposes upon irradiation to crosslink the polymer (hereinafter referred to as "photoacid generator"). , "Photo-crosslinking agent") are preferably used. Onium salt as photoacid generator,
Examples thereof include halogen-containing compounds, diazoketone compounds, sulfone compounds, sulfonic acid compounds, nitrobenzyl compounds and the like. Specifically, the compounds shown below can be exemplified.

Onium salt: Iodonium salt, sulfonium salt, phosphonium salt, diazonium salt, ammonium salt and the like can be mentioned. Preferably, the following formula

[0032]

[Chemical 6]

Compounds represented by the following are preferable, and triphenylsulfonium triflate, triphenylsulfonium hexafluoroantimonate, diphenyliodonium triflate and diphenyliodonium hexafluoroantimonate are particularly preferable.

Halogen-containing compounds: haloalkyl group-containing hydrocarbon compounds, haloalkyl group-containing heterocyclic compounds and the like can be mentioned. Preferably, the following formula

[0035]

[Chemical 7]

The compound represented by the formula (1), particularly preferably 1,1-bis (4-chlorophenyl) -2,2,2-
Examples include trichloroethane, phenyl-bis (trichloromethyl) -s-triazine and naphthyl-bis (trichloromethyl) -s-triazine.

Diazoketone compound: 1,3-diketo-2
-A diazo compound, a diazobenzoquinone compound, a diazonaphthoquinone compound, etc. can be mentioned. Preferably, the following formula

[0038]

[Chemical 8]

The compound represented by the formula (1), particularly preferably 1,2-naphthoquinonediazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-4-sulfonic acid ester of 2,3,4,4'-tetrahydrobenzophenone 1,2-Naphthoquinonediazide-4-sulfonic acid ester of 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1-bis (3,5-dimethyl-2-hydroxyphenyl) -1- [ 1,2-naphthoquinonediazide-4-sulfonic acid ester of 4- (4-hydroxybenzyl) phenyl] ethane and the like.

Sulfone compound: β-ketosulfone, β-
Examples thereof include sulfonyl sulfone. Preferably, the following formula

[0041]

[Chemical 9]

The compound represented by the formula (4) is particularly preferable, 4-trisphenacyl sulfone, mesitylphenacyl sulfone and bis (phenylsulfonyl) methane.

Nitrobenzyl compounds: Nitrobenzyl sulfonate compounds, dinitrobenzyl sulfonate compounds and the like can be mentioned. Preferably, the following formula

[0044]

[Chemical 10]

Compounds represented by the following formulas are particularly preferable: 2-nitrobenzyl tosylate, 2,4-dinitrobenzyl tosylate, 4-nitrobenzyl-9,10-
Such as diethoxyanthracene-2-sulfonate.

Sulfonic acid compounds: alkyl sulfonates, haloalkyl sulfonates, aryl sulfonates, imino sulfonates and the like can be mentioned, preferably the following formula

[0047]

[Chemical 11]

The compound represented by the formula (3) is particularly preferable, benzoin tosylate and tris triflate of pyrogallol. A positive resist composition is obtained by using only the polymer (A) and the photoacid generator.

Examples of the photocrosslinking agent include azide compounds. Specifically, the compounds shown below can be exemplified.

Azide compounds: monoazide compounds, bisazide compounds, monosulfonyl azide compounds, bissulfonyl azide compounds and the like can be mentioned. Preferably 1-azidopyrene, p-azidobenzophenone, 4 '
-Methoxy-4-azidodiphenylamine, 4-azidobenzal-2'-methoxyacetophenone, 4-azido-4'-nitrophenylazobenzene, 4,4'-diazidobenzophenone, 4,4'-diazidobenzomethane, 4, 4'-diazidostilbene, 4,4'-diazidochalcone, 4,4'-diazidodiphenyl sulfone, 3,
4'-diazidodiphenyl sulfone, 3,3'-diazidodiphenyl sulfone, 2,6-di (4'-azidobenzal) cyclohexane, 2,6-di (4'-azidobenzal) 4-methylcyclohexane, sulfonylazidobenzene , P-sulfonylazidotoluene, p-bis (sulfonylazido) benzene, 4,4′-bis (sulfonylazido) benzophenone, 2,2′-di (ethanolsulfonamide) -4,4′-diazidostilbene, 2
-Diethoxyethylsulfonamide-4,4'-diazidochalcone and the like. When a photocrosslinking agent is used, a negative resist composition is obtained.

Of these radiation-sensitive agents, photoacid generators are preferable, and onium salts and diazoketone compounds are particularly preferable. The content of these radiation-sensitive agents is preferably 1 to 100 parts by weight, and more preferably 3 to 50 parts by weight, based on 100 parts by weight of the polymer (A). If it is less than 1 part by weight, it is difficult to obtain sufficient pattern forming ability,
If it exceeds 100 parts by weight, scum tends to occur when a pattern is formed as a resist.

The composition of the present invention further comprises, if necessary,
Various compounding agents such as a dissolution inhibitor, a dissolution accelerator, an acid crosslinking agent and a surfactant can be added.

The dissolution inhibitor reduces the solubility of the polymer (A) in a developing solution consisting of an alkaline aqueous solution before irradiation with radiation, and after irradiation with radiation, it is cleaved by the acid generated by the photoacid generator to give a resist. It is a compound that improves the solubility in a developing solution consisting of an alkaline aqueous solution used at the time of pattern formation. The dissolution inhibitor can therefore be used without particular limitation as long as it is a compound having such properties.

[0054]

[Chemical 12]

[0055]

[Chemical 13]

Examples thereof include compounds represented by or a polymer having a structural unit. In the above formula, R ³² is
It is a substituted methyl group, a 1-substituted ethyl group, a silyl group, a germyl group, or an alkoxycarbonyl group, and specific examples thereof include the substituents described above as examples of the Z group.

In particular, in order to obtain a positive resist composition, it is preferable to mix a photoacid generator and a dissolution inhibitor.
The above dissolution inhibitor is based on 100 parts by weight of the polymer (A).
It is preferably 100 parts by weight or less, more preferably 10 to 10 parts by weight.
Used in 50 parts by weight.

Further, the dissolution accelerator is added to accelerate the alkali solubility of the polymer (A). Any compound or polymer having such properties can be used without particular limitation. For example, a phenol compound having about 2 to 6 benzene rings, or a poly (p-hydroxystyrene) polymer having Mw of 20,000 or less is used. Can be mentioned.
The content of the dissolution accelerator is usually 50 parts by weight or less per 100 parts by weight of the polymer (A).

The acid cross-linking agent is a compound that cross-links the polymer (A) with the acid generated by the photo-acid generator and reduces the solubility in an alkaline aqueous solution used when forming a negative resist pattern. Examples of such an acid crosslinking agent include an epoxy group,

[0060]

[Chemical 14]

[0061]

[Chemical 15]

Or

[0063]

[Chemical 16]

Compounds having a group selected from are preferred. The compounding amount of the acid crosslinking agent is usually 100 parts by weight or less per 100 parts by weight of the polymer (A).

As described above, the use of the photoacid generator and the dissolution inhibitor gives a positive resist composition, and the use of the acid generator and the acid crosslinking agent gives a negative resist composition.

The surfactant is added to improve the coatability and developability of the composition. Examples of such a surfactant include polyoxyethylene lauryl ether and polyoxyethylene stearyl ether. ,
Polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate, Ftop EF301, EF303, EF352 (trade name,
(Made by Shin-Akita Kasei Co., Ltd.), Megafax F171, F17
2, F173 (trade name, manufactured by Dainippon Ink and Chemicals), Florard FC430, FC431 (trade name, manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-38.
2, SC-101, SC-102, SC-103, SC
-104, SC-105, SC-106 (trade name, manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid-based or methacrylic acid-based (co) weight polyflow No. 75. , No.95
(Trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.) and the like.

The content of these surfactants is usually 2 parts by weight or less per 100 parts by weight of the solid content of the composition.
Other additives include azo compounds, antihalation agents composed of amine compounds, sensitizers, adhesion aids,
A storage stabilizer, a defoaming agent, etc. can be mentioned.

In the composition of the present invention, the above-mentioned polymer (A), the radiation-sensitive agent and various compounding agents optionally mixed are dissolved in a solvent so that the solid content concentration becomes 20 to 40% by weight. Let

Examples of the solvent used at this time include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 2-ethoxyethyl acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol methyl ether acetate. , Propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone,
Cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate,
Ethyl ethoxy acetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3
-Ethyl ethoxypropionate, methyl 3-ethoxypropionate, ethyl acetate, butyl acetate, 2-heptanone, 3-heptanone, 4-pentanone, ethyl pyruvate and the like can be used.

If necessary, N may be added to these solvents.
-Methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethylether, dihexylether, acetonylacetone, isophorone, Caproic acid, caprylic acid, 1-octanol, 1
It is also possible to add high-boiling solvents such as nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate and phenyl cellosolve acetate.

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, for coating on a substrate, for example, the composition of the present invention is dissolved in the above solvent so that the solid content concentration is 5 to 50% by weight, filtered, and then spin-coated, flow-coated, spin-coated. It is performed by applying a coating method such as a coating method.

The formed resist film is partially irradiated with radiation to form a fine pattern. The radiation used is not particularly limited, and includes, for example, deep ultraviolet rays such as excimer laser, X-rays such as synchrotron radiation,
A charged particle beam such as an electron beam is used depending on the type of radiation sensitive agent used. The irradiation conditions such as the radiation dose are appropriately determined according to the composition of the composition, the type of each added amount, and the like.

In the present invention, in order to improve the apparent sensitivity of the composition, 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 to 20.
The temperature is 0 ° C, preferably 50 to 150 ° C.

The developer used for the subsequent development is, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propyl to obtain a pattern. Amine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5. An alkaline aqueous solution obtained by dissolving 4.0] -7-undecene, 1,5-diazabicyclo- [4.3.0] -5-nonane and the like can be used.

An alkaline aqueous solution prepared by adding an appropriate amount of a water-soluble organic solvent, for example, alcohols such as methanol and ethanol or a surfactant to the above developing solution can also be used as the developing solution. When developing is performed using a developing solution composed of such an alkaline aqueous solution, generally, rinsing with water is subsequently performed.

[0076]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The measurement of Mw and the evaluation of the resist in the examples are carried out by the following methods.

Mw: Tosoh GPC column (G200
0H _XL 2 this, one G3000H _XL, G4000H _XL 1
The present invention) was used, and the flow rate was 1.5 ml / min, the eluting solvent was tetrahydrofuran, and the column temperature was 40 ° C.

Optimum dose: 2.38% by weight tetramethylammonium hydroxide aqueous solution, developed, rinsed with water and dried to form a resist pattern on the wafer, and a line and space pattern of 0.6 μm. The irradiation dose of the Kr-F excimer laser for forming (1L1S) in a width of 1: 1 (hereinafter, referred to as "optimum irradiation dose") was determined. The irradiation device is "MBK-400TL-" manufactured by Admon Science Co., which emits a Kr-F excimer laser.
N ”was used.

Resolution: The dimension of the minimum resist pattern resolved when irradiated with the optimum irradiation time was measured.

Residual film rate: The thickness of the pattern after development at the optimum irradiation time was divided by the thickness of the resist film before development, and this value was multiplied by 100 and expressed as a unit of%.

Developability: The scum of the unirradiated area, the degree of undeveloped area, the swelling and meandering of the irradiated area were examined.

Heat resistance: A wafer in which a resist pattern was formed was put in a clean oven, and the case where the pattern did not collapse at 150 ° C. was regarded as good.

Synthesis Example 1 122 g (1.0 mol) of 2,5-xylenol and 36.8 of 2-oxoacetic acid monohydrate were placed in a flask.
2 g (0.4 mol), 50 ml of concentrated hydrochloric acid and 200 g of methanol were charged and the reaction was carried out under reflux for 4 hours. The precipitated white compound was filtered, washed with a small amount of toluene several times, washed with a large amount of water several times, and dried to obtain the following formula (4).

[0084]

[Chemical 17]

95 g of a compound represented by the following (hereinafter referred to as "compound (a)") was obtained.

Synthesis Example 2 30 g of the compound (a) obtained in Synthesis Example 1 was placed in a flask.
(0.1 mol), para-cresol 10.8 g (0.1 mol), 37 wt% formalin 8.2 g (formaldehyde; 0.1 mol), dioxane 5 g and hydrochloric acid 1 ml were charged and reacted at 100 ° C. for 2 hours. Let After the reaction, the reaction product was diluted with 50 ml of acetone and poured into a large amount of water,
The polymer was precipitated. The polymer is filtered and the filtrate is at pH
It was washed several times with water until it showed neutrality with a test paper, dried and purified to obtain the following formula (5).

[0087]

[Chemical 18]

A polymer having the structural unit shown in was obtained. The Mw of the obtained polymer was 2,300. Let this polymer be a polymer (A1).

Synthesis Example 3 20 g of the polymer (A1) obtained in Synthesis Example 2 (20.0 g) of 3,4-dihydro-2H-pyran and 0.5 g of paratoluenesulfonic acid were dissolved in 100 ml of acetone to obtain 10
The reaction was performed at 24 ° C. for 24 hours. After the reaction, an aqueous sodium hydrogencarbonate solution was added to neutralize, the product was extracted with ethyl acetate, washed with water, and unreacted substances were removed under reduced pressure. Then, after dissolving in dioxane, the product was reprecipitated with a large amount of water, filtered, washed with water, and dried to obtain a polymer in which the phenolic hydroxyl group and the carboxyl group were tetrahydrpyranylated. Let this polymer be a polymer (A2). ¹ H
-From NMR analysis, the rate of tetrahydropyranylation of phenolic hydroxyl groups and carboxyl groups is almost 100%.
Met. The Mw of the polymer (A2) was 2,700.

Synthesis Example 4 Compound (a) 30 g (0.1 mol), para-t-butylphenol 15.0 g (0.1 mol), 37 wt% formalin 9.5 g (formaldehyde; 0.12 mol), dioxane. Charge 5 g and 1 ml of hydrochloric acid, and add 3 at 100 ° C.
A polymer having the structural unit represented by the above formula (5) was obtained in the same manner as in Synthesis Example 3 except that the reaction was carried out for a time. The Mw of the obtained polymer was 3,500. Let this polymer be a polymer (A3).

Synthesis Example 5 20 g of the polymer (A3) obtained in Synthesis Example 4, 10.0 g of benzyl chloride and 13.8 g of potassium carbonate were reacted in 100 ml of dimethylformamide at 100 ° C. for 8 hours. After the reaction, the mixture was poured into an oxalic acid aqueous solution to neutralize excess potassium carbonate, extracted with ethyl acetate, washed with water several times, and then ethyl acetate was distilled off.

Then, the residue was dissolved in 100 ml of acetone and poured into 1 l of water to precipitate a polymer. The precipitated polymer was separated by filtration, washed with water and dried to obtain the following formula (6).

[0093]

[Chemical 19]

A polymer having the structural unit shown in was obtained. Let this polymer be a polymer (A4). The Mw of the obtained polymer (A4) was 4,000.

Resins (B1) and (B2) The resin (B1) is poly (p-hydroxystyrene) having an Mw of 7,200, and the resin (B2) is 65% trimethylsilylated phenolic hydroxyl group of the resin (B1). It is a resin.

Example 1 100 parts by weight of resin (A1), 2 parts by weight of triphenylsulfonium trifluoromethanesulfonate as a photoacid generator, and 50 parts by weight of resin (B2) as a dissolution inhibitor were added to 411 parts by weight of methyl 3-methoxypropionate. , Then filtered through a 0.2 μm membrane filter,
A resist solution was obtained.

The above resist solution was applied onto a silicon wafer with a spinner and prebaked at 100 ° C. for 100 seconds to form a resist film having a thickness of 1.0 μm. A pattern was brought into close contact with the resist film and irradiated with Kr-F excimer laser, and then post-baked at 110 ° C. for 90 seconds. Next, it was immersed in a 2.38 wt% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 1 minute for development, and rinsed with water for 30 seconds. As a result, the optimum dose was 90 mJ / cm ² , the resolution was 0.30 μm, and a 0.3 μm line-and-space positive pattern having a good shape was obtained. Further, the developability was good, the residual film rate of the unirradiated area was 86%, and the heat resistance was good.

Example 2 100 parts by weight of resin (A2) and 3 parts by weight of triphenylsulfonium hexafluoroantimonate as a photoacid generator were dissolved in 278 parts by weight of ethyl 3-ethoxypropionate and filtered to obtain a resist solution. It was Using the obtained resist solution, coating, pre-baking, irradiation with radiation, baking after irradiation, development and rinsing were performed in the same manner as in Example 1.
As a result, the optimum dose was 100 mJ / cm ² , the resolution was 0.30 μm, and a line-and-space positive type pattern having a good shape of 0.30 μm was obtained. Also,
The developability is good, and the residual film ratio of the unirradiated area is 98%.
And the heat resistance was good.

Example 3 100 parts by weight of resin (A3), 5 parts by weight of diphenyliodonium tetrafluoroborate as a photoacid generator and 40 parts by weight of hexamethoxymethylmelamine as an acid crosslinking agent were dissolved in 392 parts by weight of ethyl pyruvate, A resist solution was obtained by filtration. Using the obtained resist solution, coating, pre-baking, irradiation with radiation, baking after irradiation, development and rinsing were performed in the same manner as in Example 1. As a result, the optimum dose was 120 mJ / cm ² , the resolution was 0.34 μm, and a 0.34 μm line-and-space negative pattern having a good shape was obtained. Further, the developability was good, the residual film ratio of the non-irradiated portion was 97%, and the heat resistance was good.

Example 4 100 parts by weight of resin (A4), 2,3 as a photo-acid generator
Dissolve 5 parts by weight of 1,2-naphthoquinonediazide-4-sulfonic acid ester of 4,4'-tetrahydroxybenzophenone (average esterification rate: 75%) in 284 parts by weight of ethyl 2-hydroxypropionate, and filter to obtain a resist. A solution was obtained. Using the obtained resist solution, coating, pre-baking, irradiation with radiation, baking after irradiation, development and rinsing were performed in the same manner as in Example 1. As a result, the optimum dose is 65
mJ / cm ² , the resolution was 0.30 μm, and a 0.30 μm line-and-space positive pattern having a good shape was obtained. In addition, the developability was good, the residual film rate of the unirradiated area was 96%, and the heat resistance was good.

Example 5 100 parts by weight of the resin (A2), the resin (B
1) 10 parts by weight, 5 parts by weight of 1,2-naphthoquinonediazide-4-sulfonic acid ester of 1,1,1-tris (4-hydroxyphenyl) ethane (average esterification rate 70%) as a photoacid generator It was dissolved in 311 parts by weight of 2-ethoxyethyl acetate and filtered to obtain a resist solution.
Application using the obtained resist solution in the same manner as in Example 1,
Pre-baking, irradiation, post-irradiation baking, development and rinsing were performed. As a result, the optimum dose is 100 mJ / c
m ² , resolution is 0.30 μm, and good shape is 0.3
A line and space positive pattern of 0 μm was obtained. Further, the developability was good, the residual film ratio of the non-irradiated portion was 96%, and the heat resistance was good.

[0102]

EFFECTS OF THE INVENTION The radiation-sensitive resin composition of the present invention enables stable microfabrication, high sensitivity, high resolution, dry etching resistance, developability, adhesiveness, heat resistance and residual film resistance. It is suitable as a resist composition having excellent performance. Further, the radiation-sensitive resin composition of the present invention contains X-rays such as synchrotron radiation other than deep ultraviolet rays such as excimer laser,
Since it can deal with any radiation such as charged particle beam such as electron beam, it can be advantageously used as a resist for manufacturing integrated circuits, which is expected to be further miniaturized in future.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G03F 7/038 505 H01L 21/027 (72) Inventor Takao Miura 2-11, Tsukiji, Chuo-ku, Tokyo No. 24 within Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. (A) The following formula (1): And / or the following formula (2) A radiation-sensitive resin composition comprising a polymer having a repeating unit represented by and (B) a radiation-sensitive agent.