JP3175126B2 - Radiation-sensitive resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a radiation-sensitive resin composition. More specifically, the present invention relates to a radiation-sensitive resin composition particularly 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 fine processing represented by the manufacture of integrated circuits, the processing size in lithography has been further reduced 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, even in resists used for microfabrication,
It is necessary to form a pattern having a size of 0.5 μm or less with high accuracy. However, in the conventional method using visible light (700 to 400 nm) or near ultraviolet light (400 to 300 nm), a fine pattern of 0.5 μm or less can be formed with high accuracy. It is extremely difficult to form. Therefore, the short wavelength (300
Lithography using radiation has been studied.

Examples of such radiation include far-ultraviolet rays typified by the emission line spectrum (254 nm) of a mercury lamp, KrF excimer laser (248 nm), X-rays, charged particle beams, and the like. Of particular interest is lithography using excimer lasers. For this reason, resists used for lithography are also processed by excimer laser.
High sensitivity for fine patterns of 5 μm or less, developability (no scum or residual image at the time of development), residual film property (the film does not decrease at the time of development), adhesiveness (the resist pattern does not peel off at the time of 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 dryness of the etching process is progressing, and the dry etching resistance of the resist is an important requirement for performance.

[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 that can stably perform microfabrication, has high sensitivity, high resolution, and has excellent properties such as dry etching resistance, developability, residual film properties, adhesion, and heat resistance. To provide a radiation-sensitive resin composition that is suitable as the above.
Still other 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 as follows: (A) The following formula (1)

[0006]

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[0007] In repeating unit and / or the following formula expressed (2)

[0008]

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A polymer having a repeating unit represented by the formula (B):
Lower, is achieved by the positive-tone radiation-sensitive resin composition characterized by containing a) as "photoacid generator".

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

In the above formula (1) or (2), 2 to 2 of Ar
Preferred examples of the octavalent aromatic ring include the following formula:

[0012]

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And the like.

Examples of the alkyl group for R ¹ in the above formula (1) or (2) include a methyl group, an ethyl group and an n-
Examples include a propyl group, an isopropyl group, an n-butyl group, a t-butyl group and the like. Preferably it is a methyl group.

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

Specific examples of the substituent which can be 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, the substituted methyl group includes, for example, methoxymethyl group, methylthiomethyl group, methoxyethoxymethyl group, tetrahydropyranyl group, tetrahydrothiopyranyl group, tetrahydrofuranyl group, tetrahydrothiofuranyl group, benzyloxymethyl 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-
Butyl group, 1,1-dimethylpropyl group and the like, and silyl groups such as trimethylsilyl group, triethylsilyl group,
t-butyldimethylsilyl group, isopropyldimethylsilyl group, phenyldimethylsilyl group, etc.

The germyl group includes trimethylgermyl group, triethylgermyl group, t-butyldimethylgermyl group, isopropyldimethylgermyl group, phenyldimethylgermyl group and the like, and the alkoxycarbonyl group includes methoxycarbonyl group and ethoxycarbonyl group. Group, t-
Butoxycarbonyl group and the like.

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

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 . -Oxoacetec acid (CHO-COOH) is obtained by polycondensing aldehydes. 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) include, for example, benzene, toluene, naphthalene,
Aromatic hydrocarbons such as pyrene and durene; phenol,
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, Phenol derivatives such as phlorogrisinol; hydroxybenzoic acid derivatives such as hydroxybenzoic acid, dihydroxybenzoic acid and trihydroxybenzoic acid; and aromatic amine derivatives such as aniline, toluidine and phenylenediamine.
The compounds represented by the above formula (3) may be used alone or as a mixture of two or more.

The aldehyde used in the present invention contains 2-oxoacetic acid. Other aldehydes other than 2-oxoacetic acid include, for example, formaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, 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,
Examples thereof include pn-butylbenzaldehyde and furfural, and acetaldehyde and formaldehyde can be particularly preferably used.

As the aldehyde used in the present invention, 2-oxoacetic acid may be used alone or in combination with the other aldehydes described above. 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 to be used is preferably 0.1 to 3 mol, more preferably 0.3 to 1.5 mol, per 1 mol of the compound represented by the formula (3).

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

In the polycondensation, the reaction medium is not particularly limited, but for example, water is used. When the compound represented by the formula (3) used for the polycondensation is not dissolved in the aqueous solution and becomes inhomogeneous from the beginning 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; and cyclic ethers such as tetrahydrofuran and dioxane. The amount of the reaction medium is usually 20 to 1,000 parts by weight per 100 parts by weight of the reaction raw material.

The temperature of the polycondensation can be appropriately adjusted according to the reactivity of the reaction raw materials.
° C, preferably 70 to 150 ° C. As the polycondensation method, a compound represented by the formula (3), aldehydes and a catalyst are charged at once, and a compound represented by the formula (3), aldehydes and / or a catalyst are added as the reaction proceeds. Examples of the method include a method of adding, a method of obtaining a low molecular weight compound having a repeating unit represented by the formula (1), and then adding an aldehyde and / or a catalyst.

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

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

[0030] (B) an onium salt, a halogen-containing compound as component der Ru photoacid generator, diazoketone compounds, sulfone compounds, sulfonic acid compounds, and nitrobenzyl compounds. Specifically, the following compounds can be exemplified.

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

[0032]

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And particularly preferably triphenylsulfonium triflate, triphenylsulfonium hexafluoroantimonate, diphenyliodonium triflate, diphenyliodonium hexafluoroantimonate, etc.

Halogen-containing compound: Examples include a haloalkyl group-containing hydrocarbon compound and a haloalkyl group-containing heterocyclic compound. Preferably, the following formula

[0035]

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And particularly preferably 1,1-bis (4-chlorophenyl) -2,2,2-
Trichloroethane, phenyl-bis (trichloromethyl) -s-triazine, naphthyl-bis (trichloromethyl) -s-triazine and the like.

Diazoketone compound: 1,3-diketo-2
-Diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds and the like. Preferably, the following formula

[0038]

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And 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 1,1,1,1-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 compounds: β-ketosulfone, β-
Sulfonyl sulfone and the like can be mentioned. Preferably, the following formula

[0041]

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[0042] a compound represented by, and particularly preferably 4-tri Le phenacyl sulfone, mesityl phenacyl sulfone, bis (phenylsulfonyl) methane and the like.

Nitrobenzyl compound: nitrobenzylsulfonate compound, dinitrobenzylsulfonate compound and the like can be mentioned. Preferably, the following formula

[0044]

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And particularly preferably 2-nitrobenzyl tosylate, 2,4-dinitrobenzyl tosylate, 4-nitrobenzyl-9,10-
And diethoxyanthracene-2-sulfonate.

Sulfonic acid compounds: Alkyl sulfonic acid esters, haloalkyl sulfonic acid esters, aryl sulfonic acid esters, iminosulfonates and the like are preferred.

[0047]

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And particularly preferably benzoin tosylate, pyrogallol tris triflate and the like. When only the polymer (A) and the photoacid generator are used, a positive resist composition is obtained.

[0049]

[0050]

[0051] These Chi sac photoacid generator, onium salts, especially, diazoketone compounds and the like are preferable. These photo acids
The amount of the generator is preferably 1 to 100 parts by weight, more preferably 3 to 50 parts by weight, based on 100 parts by weight of the polymer (A). When the amount is less than 1 part by weight, it is difficult to obtain a sufficient pattern forming ability, and when the amount exceeds 100 parts by weight, scum tends to be generated when a pattern is formed as a resist.

The composition of the present invention may further comprise, if necessary,
Dissolution inhibitors, solubility enhancers, can contain various compounding agents such as interfacial active agent.

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

[0054]

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[0055]

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And 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 for the Z group.

[0057] In particular, it is preferable to incorporate a dissolution inhibitor and a photoacid generator. The dissolution inhibitor comprises a polymer (A) 10
It is preferably used in an amount of 100 parts by weight or less, more preferably 10 to 50 parts by weight, based on 0 parts by weight.

[0058] The dissolution promoter is added to promote 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 a Mw of 20,000 or less is used. No.
The compounding amount of the dissolution promoter is usually 50 parts by weight or less per 100 parts by weight of the polymer (A).

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

Surfactants are incorporated to improve the coating properties and developability of the composition. Examples of such surfactants 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, F-top EF301, EF303, EF352 (trade names,
Shin-Akita Chemical Co., Ltd.), Megafax F171, F17
2, F173 (trade name, manufactured by Dainippon Ink), Florado 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 or methacrylic acid (co) weight polyflow No. 75 , No.95
(Trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like.

The amount of these surfactants is usually not more than 2 parts by weight per 100 parts by weight of the solid content of the composition.
Other additives include an azo compound, an antihalation agent comprising an amine compound, a sensitizer, an adhesion aid,
Examples thereof include a storage stabilizer and an antifoaming agent.

The composition of the present invention is prepared by adding the above-mentioned polymer (A), a photoacid generator and various compounding agents, if necessary, to a solvent so that the solid content concentration becomes 20 to 40% by weight. Allow to dissolve.

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, and 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 ethoxyacetate, 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.

In these solvents, if necessary, N
-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
-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 can also be added.

The composition of the present invention is applied in the form of the above solution on a substrate such as a silicon wafer and dried to form a resist film. In this case, for application on the substrate, for example, the composition of the present invention is dissolved in the above-mentioned solvent so that the solid content concentration becomes 5 to 50% by weight, filtered, and then spin-coated, flow-coated, and rolled. This is carried out by application such as a rule application.

The formed resist film is partially irradiated with radiation in order to form a fine pattern. There is no particular limitation on the radiation used, 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 the radiation-sensitive agent used. Irradiation conditions such as 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 perform heating after irradiation. The heating conditions vary depending on the composition of the composition, the type of each additive, and the like.
0 ° C, preferably 50 to 150 ° C.

The developer used in the subsequent development may be, 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, pyrrol, piperidine, 1,8-diazabicyclo [5. For example, 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 obtained by adding an appropriate amount of a water-soluble organic solvent, for example, an alcohol such as methanol or ethanol or a surfactant to the above-mentioned developer can also be used as the developer. When development is performed using a developing solution composed of such an alkaline aqueous solution, rinsing is generally continued with water.

[0076]

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

Mw: Tosoh GPC column (G200
0H _XL 2 this, one G3000H _XL, G4000H _XL 1
Using this method, the measurement was carried out with a differential refraction detector by gel permeation chromatography using monodisperse polystyrene as a standard under a flow rate of 1.5 ml / min, an eluting solvent of tetrahydrofuran, and a column temperature of 40 ° C.

Optimum irradiation dose: developing with 2.38% by weight aqueous solution of tetramethylammonium hydroxide, rinsing with water, and drying to form a resist pattern on the wafer, and a 0.6 μm line and space pattern The irradiation amount of Kr-F excimer laser for forming (1L1S) in a one-to-one width (hereinafter referred to as "optimal irradiation amount") was obtained. 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 for the optimum irradiation time was measured.

Residual film ratio: 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 in units of%.

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

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

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

[0084]

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95 g of a compound represented by the following formula (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), 10.8 g (0.1 mol) of paracresol, 8.2 g of 37% by weight formalin (formaldehyde; 0.1 mol), 5 g of dioxane and 1 ml of hydrochloric acid, and reacted at 100 ° C. for 2 hours. I let it. After the reaction, the reaction was diluted with 50 ml of acetone, poured into a large amount of water,
The polymer was precipitated. The polymer is filtered and the filtrate is adjusted to pH
After washing with water several times with a test paper until it shows neutrality, drying and purification, the following formula (5)

[0087]

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A polymer having the structural unit shown in the above was obtained. Mw of the obtained polymer was 2,300. This polymer is referred to as a polymer (A1).

Synthesis Example 3 20 g of the polymer (A1) obtained in Synthesis Example 2 and 20.0 g of 3,4-dihydro-2H-pyran and 0.5 g of paratoluenesulfonic acid were dissolved in 100 ml of acetone.
The reaction was performed at 24 ° C. for 24 hours. After the reaction, an aqueous sodium hydrogen carbonate solution was added for neutralization, and then 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, separated by filtration, washed with water, and dried to obtain a polymer in which a phenolic hydroxyl group and a carboxyl group were tetrahydropyranylated. This polymer is referred to as a polymer (A2). ¹ H
According to the analysis by NMR, the rate of tetrahydropyranylation of the phenolic hydroxyl group and the carboxyl group was almost 100%.
Met. Mw of the polymer (A2) was 2,700.

Synthesis Example 4 30 g (0.1 mol) of compound (a), 15.0 g (0.1 mol) of para-t-butylphenol, 9.5 g of 37% by weight formalin (formaldehyde; 0.12 mol), dioxane 5 g and 1 ml of hydrochloric acid were charged,
A polymer having a structural unit represented by the above formula (5) was obtained in the same manner as in Synthesis Example 3 except that the reaction was performed for a time. Mw of the obtained polymer was 3,500. This polymer is referred to as 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 aqueous solution of oxalic acid to neutralize excess potassium carbonate, extracted with ethyl acetate, washed several times with water, and then distilled off the ethyl acetate.

Next, 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, and was treated by the following formula (6).

[0093]

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A polymer having the structural unit shown in the above was obtained. This polymer is referred to as a polymer (A4). Mw of the obtained polymer (A4) was 4,000.

Resins (B1) and (B2) Resin (B1) is a poly (p-hydroxystyrene) having a Mw of 7,200, and resin (B2) is a resin (B1) having a phenolic hydroxyl group of 65% by trimethylsilylation. 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 411 parts by weight of methyl 3-methoxypropionate. And filtered through a 0.2 μm membrane filter.
A resist solution was obtained.

The above-mentioned resist solution was applied on a silicon wafer by a spinner, and then prebaked at 100 ° C. for 100 seconds to form a resist film having a thickness of 1.0 μm. After the pattern was brought into close contact with the resist film and irradiated with a Kr-F excimer laser, baking was performed after irradiation at 110 ° C. for 90 seconds. Next, the film was developed by immersion in a 2.38% by weight aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 1 minute, and rinsed with water for 30 seconds. As a result, the optimum irradiation amount 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 ratio of the unirradiated portion 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, followed by filtration to obtain a resist solution. Was. Using the obtained resist solution, coating, pre-baking, radiation irradiation, post-irradiation baking, development and rinsing were performed in the same manner as in Example 1.
As a result, the optimum irradiation amount was 100 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. Also,
Good developability, 98% residual film ratio in unirradiated area
And the heat resistance was good.

[0099]

Example 3 100 parts by weight of resin (A4), 2,3,
5 parts by weight of 1,2-naphthoquinonediazide-4-sulfonic acid ester of 4,4'-tetrahydroxybenzophenone (average esterification rate: 75%) was dissolved in 284 parts by weight of ethyl 2-hydroxypropionate, filtered, 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 optimal 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 ratio in the unirradiated part was 96%, and the heat resistance was good.

Example 4 100 parts by weight of resin (A2) and resin (B) as a dissolution promoter
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.
Using the obtained resist solution, apply in the same manner as in Example 1,
Prebaking, irradiation, baking after irradiation, development, and rinsing were performed. As a result, the optimal dose is 100 mJ / c
m ² , the resolution is 0.30 μm, and 0.3
A 0 μm line-and-space positive pattern was obtained. Further, the developability was good, the residual film ratio of the unirradiated portion was 96%, and the heat resistance was good.

[0102]

The radiation-sensitive resin composition of the present invention can stably perform fine processing, has high sensitivity, high resolution, and has dry etching resistance, developability, adhesion, heat resistance, residual film properties, and the like. It is suitable as a resist composition having excellent performance. In addition, the radiation-sensitive resin composition of the present invention may include X-rays such as synchrotron radiation in addition to far ultraviolet rays such as excimer lasers,
Since it can cope with any kind of radiation such as a charged particle beam such as an electron beam, it can be advantageously used as a resist for manufacturing integrated circuits, which is expected to be further miniaturized in the future.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takao Miura 2--11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd. (56) References JP-A-58-133461 (JP, A) JP-A Sho 61-7836 (JP, A) JP-A-2-214863 (JP, A) JP-A-3-150567 (JP, A) JP-A-3-130774 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03F ^7/ 00-7/42

Claims (1)

(57) [Claims] (A) The following formula (1): And / or the following formula (2): A positive radiation-sensitive resin composition comprising: a polymer having a repeating unit represented by the formula: and (B) a compound capable of generating an acid upon irradiation .