JPH05333539A - Radiation sensitive resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition excellent in developability, pattern shape, dimensional fidelity and focus allowance by incorporating an alkali-soluble resin and a specified compd. CONSTITUTION:The composition contains an alkali-soluble resin, preferably novolac resin and a compd. shown by the formula, and further contains a compd. having a quinone-azide group when all Ds are hydrogen atom. In the formula, X<1>,... X<9> are the same or different and are hydrogen atom, alkyl, alkenyl or-OD group (where D is hydrogen atom or an org. group having a quinone-diazide group), R is hydrogen atom or alkyl, and at least one among X<1>,... X<9> is -OD group. Resol resin, poly(vinylphenol), its derivative, etc., are used as the alkali- soluble resin as well as novolac resin.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a radiation-sensitive resin composition containing an alkali-soluble resin and useful as a resist for producing a highly integrated integrated circuit.

[0002]

2. Description of the Related Art Conventionally, positive resists have been widely used in the manufacture of integrated circuits because a resist pattern of high resolution can be obtained. However, with the progress of high integration in recent years, resists of higher resolution have been obtained. A positive resist capable of forming a pattern is desired. That is, in order to form a fine resist pattern with a positive resist, the exposed portion is in contact with a base material such as a wafer when a latent image formed by exposure is developed with a developer containing an alkaline aqueous solution. It is necessary to develop quickly to the part (the bottom of the pattern), but with the conventional positive resist, the line width of the resist pattern to be formed is 0.8 μm.
When the fineness was less than m, the developability and the pattern shape were not sufficient. Further, in order to manufacture an integrated circuit with a high degree of integration, a resist that faithfully reproduces the design dimension of the mask by reducing the difference between the design dimension of the mask and the dimension of the actual resist pattern, that is, the dimension fidelity is high. Although a resist is required, in general, the narrower the pattern line width, the larger the difference between the mask design size and the actual resist pattern size. Fidelity could not be achieved. Furthermore, in the conventional positive resist, if the focus shifts during the exposure by the stepper, the pattern shape is deformed, the developability is deteriorated, and the difference with the designed line width becomes significant.
It was not enough in terms of focus tolerance.

[0003]

Therefore, an object of the present invention is to provide a novel radiation-sensitive resin composition, and more specifically, it has good developability and an excellent pattern shape, and In particular, it is to provide a radiation-sensitive resin composition useful as a positive resist having excellent dimensional fidelity and focus tolerance.

[0004]

According to the present invention, the above-mentioned problems can be solved by using an alkali-soluble resin and the following general formula (1).

[In the general formula (1), X ^{1 to} X ⁹ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkoxy group or an -OD group (wherein D is a hydrogen atom or a quinonediazide group). And an R is a hydrogen atom or an alkyl group. However, at least one of X ^{1 to} X ⁹ is an —OD group. And a compound represented by the formula (1) and all D's in the general formula (1) are hydrogen atoms, a radiation-sensitive resin composition characterized by further containing a compound having a quinonediazide group To be done.

The present invention will be specifically described below, but the purpose, constitution and effect of the present invention will be clarified by this. First, as the alkali-soluble resin used in the present invention, for example, novolac resin, resole resin, poly (vinylphenol) or its derivative, styrene-maleic acid polymer, poly (vinylhydroxybenzoate), carboxyl group-containing acrylic acid. Examples of the polymer include a carboxyl group-containing methacrylic acid polymer.

The preferred alkali soluble resin is a novolac resin. A particularly preferred novolac resin has the following formula

[Chemical 2] (Here, m is an integer of 1 to 3.) It is obtained by polycondensing phenols and aldehydes represented by.

Examples of the phenols include o-cresol, m-cresol, p-cresol and 2,3-
Examples include xylenol, 2,5-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol and the like. These phenols are used alone or in combination of two or more.

Of the above phenols, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,5-xylenol, 3,4-xylenol, 3,5-xylenol and 2,3,5. -Trimethylphenol is preferred. Further, a particularly preferable combination of phenols is, by weight ratio, m-cresol / 2,3-xylenol / p-cresol = 95-
20 / 5-60 / 0-75, m-cresol / 3,5-
Xylenol / p-cresol = 95-30 / 5-70
/ 0-65, m-cresol / 2,3,5-trimethylphenol / p-cresol = 95-35 / 5-60 /
0-60, m-cresol / 2,3-xylenol /
3,4-xylenol = 95-35 / 5-85 / 0-6
0, m-cresol / 2,5-xylenol / 3,5-
Xylenol = 95-25 / 5-70 / 0-70, m-
Cresol / 2,3-xylenol / 2,3,5-trimethylphenol = 95-35 / 5-85 / 0-60,
m-cresol / 2,5-xylenol / 2,3,5-
Trimethylphenol = 95-35 / 5-70 / 0-6
0, m-cresol / 3,4-xylenol / 2,3,
5-trimethylphenol = 95-35 / 5-50 / 0
~ 60, m-cresol / 3,5-xylenol / 2,
3,5-Trimethylphenol = 95-35 / 5-70
/ 0-60, m-cresol / p-cresol = 90-
It is composed of 30/10 to 75 etc.

Examples of the aldehydes to be polycondensed with the phenols include formaldehyde, trioxane, paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxy. Benzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-chlorobenzaldehyde,
m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-
Methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde, furfural and the like are preferable, and of these, formaldehyde is particularly preferable.

When formaldehyde is used as the aldehyde, examples of the formaldehyde source include formalin, trioxane, paraformaldehyde, and hemiformals such as methyl hemiformal, ethyl hemiformal, propyl hemiformal, butyl hemiformal, and phenyl hemiformal. Can be mentioned. Of these, formalin and butyl hemiformal are particularly preferred.

The aldehydes can be used alone or in combination of two or more. The amount of aldehydes used is preferably 0.7 to 3 mol per mol of phenols.

An acid catalyst is usually used for the polycondensation of the phenols and the aldehydes. Examples of the acidic catalyst include hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, acetic acid and the like. The amount of these acidic catalysts used is usually 1 × 10 ^{−5 to} 5 per mol of phenols.
× 10 ^-1 mol.

In the polycondensation of phenols and aldehydes, water is usually used as the reaction medium, but when the phenols used do not dissolve in the aqueous solution of aldehydes and become a heterogeneous system from the beginning of the reaction. It is also possible to use hydrophilic solvents as reaction medium. Examples of the hydrophilic solvent include alcohols such as methanol, ethanol, propanol and butanol, and 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 of the phenols and the aldehydes is appropriately adjusted depending on the reactivity of the reaction raw materials, but is usually 10 to 200 ° C.

As the polycondensation method of phenols and aldehydes, phenols, aldehydes, acidic catalysts and the like are charged all at once and reacted, or phenols, aldehydes and the like are gradually added in the presence of an acidic catalyst. While reacting, a method or the like can be adopted.

After completion of the polycondensation reaction, in order to remove unreacted raw materials, acidic catalyst, reaction medium, etc. present in the reaction system,
Generally, the reaction system is heated to 130-230 ° C,
Volatile components are removed under reduced pressure, for example, under a pressure of about 20 to 50 mmHg, and the produced novolac resin is recovered.

The weight average molecular weight in terms of polystyrene (hereinafter referred to as "Mw") of the alkali-soluble resin used in the present invention.
That. ) Can be appropriately selected from the range of the molecular weight of the alkali-soluble resin conventionally used in the radiation-sensitive resin composition, but it is preferably 2,000 to 20,000, more preferably 3, 000-2
50,000 (hereinafter, Mw is 3,000 to 20,0)
Alkali-soluble resin in the range of 00 is referred to as "resin (A)"). If the Mw exceeds 20,000, it may be difficult to uniformly apply the composition of the present invention onto the substrate, and the developability and sensitivity tend to be lowered. On the other hand, when Mw is less than 2,000, heat resistance tends to decrease. In particular, when a high molecular weight novolac resin is desired, the novolac resin obtained by the polycondensation reaction is dissolved in a good solvent such as ethylene glycol monomethyl ether acetate, dioxane, methanol or ethyl acetate, and then water or n-hexane is used. , N-heptane or the like may be mixed and the precipitated novolak resin may be separated from the solution layer to recover the fractionated high molecular weight novolak resin.

Further, in the present invention, a low molecular weight phenol compound may be used in combination with an alkali-soluble resin, whereby the alkali solubility of the alkali-soluble resin is improved. The low molecular weight phenol compound is not particularly limited, but preferably has a benzene ring number of about 2 to 6. Specific examples thereof include compounds represented by the following formula.

[Chemical 3] ,

[Chemical 4] ,

[Chemical 5] ,

[Chemical 6] ,

[Chemical 7] ,

[Chemical 8] ,

[Chemical 9] ,

[Chemical 10] [Here, a, b and c are each an integer of 0 to 3 (however, a, b and c are not 0 at the same time), and x, y and z are each an integer of 0 to 3] .. ] The amount of these low molecular weight phenol compounds used is usually 5 per 100 parts by weight of the alkali-soluble resin.
It is 0 parts by weight or less.

In the present invention, particularly when the resin (A) is used, a low molecular weight alkali-soluble novolac resin and / or an alkali-soluble resole resin (hereinafter referred to as "resin (B)") may be used in combination. it can.

The resin (B) is obtained by polycondensation of phenols and aldehydes. As the phenols, those mentioned for the novolak resin of the alkali-soluble resin, phenol, 1-
Other phenols such as naphthol, 2-naphthol can be used. Further, as the aldehydes, those listed for the novolak resin can be used. The amount of the aldehydes used is usually 0.2 to 0.8 mol per mol of the phenols. In this polycondensation reaction, a basic catalyst can be used in addition to the acidic catalyst used in the production of the novolak resin.

Specific examples of such a resin (B) include:
Phenol / formaldehyde polycondensation resin, o-cresol / formaldehyde polycondensation resin, m-cresol /
Examples thereof include formaldehyde polycondensation resin, p-cresol / formaldehyde polycondensation resin, m-cresol / p-cresol / formaldehyde polycondensation resin and the like.

The Mw of the resin (B) is usually 200 to 1,5.
00, and preferably 300 to 1,000.

The amount of the resin (B) compounded is usually the resin (A).
It is 50 parts by weight or less with respect to 100 parts by weight.

Next, in the compound represented by the general formula (1), X ^{1 to} X ⁹ may be the same or different, and a hydrogen atom, an alkyl group, an alkoxy group or an -OD group (where D is a hydrogen atom) Or an organic group having a quinonediazide group), but at least one, preferably 1 to 4 of X ^{1 to} X ⁹ must be an -OD group. Of X ^{1 to} X ⁹ , the alkyl group is preferably one having 4 or less carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a t-butyl group and the like. Can be mentioned. The alkoxy group preferably has 4 or less carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group and a butoxy group. In addition, as the organic group having a quinonediazide group among D in the -OD group, for example, 1,2-
Benzoquinonediazide-4-sulfonyl group, 1,2-naphthoquinonediazide-4-sulfonyl group, 1,2-naphthoquinonediazide-5-sulfonyl group, 1,2-naphthoquinonediazide-6-sulfonyl group, 2,1-naphthoquinonediazide A quinonediazidesulfonyl group such as a -4-sulfonyl group and a 2,1-naphthoquinonediazide-5-sulfonyl group is preferable. Among them, a 1,2-naphthoquinonediazide-4-sulfonyl group, a 1,2-naphthoquinonediazide-5-sulfonyl group and a 1,2-naphthoquinonediazidesulfonyl group are particularly preferable. Further, in the compound represented by the general formula (1), R represents a hydrogen atom or an alkyl group, and examples of the alkyl group include the same ones as in the case of the above X ^{1 to} X ^9. ..

In the compound represented by the general formula (1),
Specific examples of the compound in which D 2 is a hydrogen atom, that is, the OD group is a hydroxyl group (hereinafter, referred to as “compound (a)”) include compounds represented by the following formulas.

[Chemical 11] ,

[Chemical formula 12] ,

[Chemical 13] ,

[Chemical 14] ,

[Chemical 15] ,

[Chemical 16] ,

[Chemical 17] ,

[Chemical 18] ,

[Chemical 19] ,

[Chemical 20] ,

[Chemical 21] ,

[Chemical formula 22] ,

[Chemical formula 23] ,

[Chemical formula 24] ,

[Chemical 25] ,

[Chemical formula 26] ,

[Chemical 27] ,

[Chemical 28]

The compound (a) can be obtained by, for example, reacting phenols with cinnamic acids in the presence of an acidic catalyst, or SYNTHETIC COMMUNICATION, 1
7 (6), 723-727 (1987), and a method of reacting a phenol with a benzaldehyde and Meldrum's acid in the presence of a basic catalyst. Phenols used here include resorcinol, catechol, hydroquinone, and 2
-Methylresorcinol, methylhydroquinone, phlorogricinol, pyrogallol, hydroxyhydroquinone and the like are preferable.

In the compound represented by the general formula (1),
A compound in which a part or all of D is an organic group having a quinonediazide group (hereinafter referred to as "compound (b)") includes 1,2-naphthoquinonediazide-4 of compound (a) in which D is a hydrogen atom. -Sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester, 1,2
-Naphthoquinonediazide-6-sulfonic acid ester,
Examples thereof include 2,1-naphthoquinonediazide-4-sulfonic acid ester, 2,1-naphthoquinonediazide-5-sulfonic acid ester, and 1,2-benzoquinonediazide-4-sulfonic acid ester. Of these, preferred compounds are 1,2-naphthoquinonediazide-4-
Sulfonate, 1,2-naphthoquinonediazide-
1,2-quinonediazide sulfonic acid ester such as 5-sulfonic acid ester.

The compound (b) is, for example, the compound (a).
And 1,2-naphthoquinonediazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-5-sulfonyl chloride and other quinonediazidesulfonyl halides,
It can be obtained by carrying out an esterification reaction in the presence of a basic catalyst. In this case, the reaction ratio between the compound (a) and the quinonediazidesulfonyl halide is preferably 0.2 to 1 mol of the quinonediazidesulfonyl halide per 1 gram equivalent of the phenolic hydroxyl group of the compound (a), particularly preferably 0. 4 to 1 mol.

In the present invention, the compound represented by the general formula (1) is used alone or in combination of two or more kinds. The amount used is usually 10
5 to 50 parts by weight, especially 10 to 0 parts by weight
30 parts by weight is preferred. By thus compounding the compound represented by the general formula (1), generation of scum during development and residual development are reduced, resulting in excellent developability, pattern shape, dimensional fidelity and focus tolerance. Is improved.

In the present invention, when the compound (b) is not used, it is necessary to add a compound having a quinonediazide group other than the compound (b) (hereinafter referred to as "compound (c)"). As the compound (c), 1,2-
Naphthoquinonediazide-4-sulfonic acid ester, 1,
2-naphthoquinonediazide-5-sulfonic acid ester,
1,2-naphthoquinonediazide-6-sulfonic acid ester, 2,1-naphthoquinonediazide-4-sulfonic acid ester, 2,1-naphthoquinonediazide-5-sulfonic acid ester, 1,2-benzoquinonediazide-4-sulfonic acid ester Examples thereof include 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester.
2-quinonediazide sulfonic acid ester is preferred. These compounds (c) can be blended also when using the compound (b).

Specific examples of the compound (c) include 2,3
4-trihydroxybenzophenone, 2,3,4,4 '
-Tetrahydroxybenzophenone, 3'-methoxy-
2,3,4,4'-tetrahydroxybenzophenone,
2,2 ', 5,5'-tetramethyl-2 ", 4,4'-
Trihydroxytriphenylmethane, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -4 ′-[1- (4-hydroxyphenyl) -1-methylethyl ] 1,2-naphthoquinonediazide-4, which is a compound containing a phenolic hydroxyl group such as 1-phenylethane and 2,4,4-trimethyl-2 ', 4', 7-trihydroxy-2-phenylflavan
-Sulfonic acid ester or 1,2-naphthoquinonediazide-5-sulfonic acid ester, and the hydrogen atom of the hydroxyl group of the resin (B) are, for example, 0.2 to 1 mol, preferably 0. An example is 1,2-quinonediazide-5-sulfonic acid ester substituted with a 1,2-naphthoquinonediazide-5-sulfonyl group at a ratio of 4 to 1 mol.

The compounding amount of the compound (c) in the present invention is
The amount is preferably 100 parts by weight or less, more preferably 5 to 50 parts by weight, based on 100 parts by weight of the alkali-soluble resin.

As described above, the composition of the present invention contains the compound (b) and / or the compound (c),
The total amount of the component having a quinonediazide group, that is, the compound (b) and the compound (c) in the composition of the present invention is
It is appropriately selected in consideration of the developing characteristics of the composition and the characteristics of the resist pattern. The content of the quinonediazide group in the solid content of the composition is preferably 5 to 35% by weight, more preferably 10 to 20% by weight.

Further, various additives such as a sensitizer and a surfactant can be optionally added to the composition of the present invention. The sensitizer improves the sensitivity of the resist to radiation, and examples thereof include 2H-pyrido- (3,2-b) -1,4-oxazine-3 (4.
H) -ones, 10H-pyrido- (3,2-b) -1,
4-benzothiazines, urazoles, hydantoins, parbituric acids, glycine anhydrides, 1-hydroxybenzotriazoles, alloxans, maleimides and the like can be mentioned. The blending amount of these sensitizers is preferably 50 parts by weight or less with respect to 100 parts by weight of the alkali-soluble resin.

The above-mentioned surfactant has an effect of improving the coatability and developability, and examples thereof include polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenyl ether and polyoxy. In addition to nonionic surfactants such as ethylene nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate,
KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) which is an organopolysiloxane polymer, and Polyflow No. which is an acrylic acid-based or methacrylic acid-based polymer. 75, No. 95
(Trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.), and F-top EF301, EF303, EF352 (trade name, manufactured by Shin-Akita Kasei), Megafax F171, F172, F17.
3 (trade name, made by Dainippon Ink), Florard FC43
0, FC431 (trade name, manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC-10
1, SC-102, SC-103, SC-104, SC
Fluorine-based surfactants such as -105 and SC-106 (trade name, manufactured by Asahi Glass) can be mentioned. The content of these surfactants is preferably 2 parts by weight or less with respect to 100 parts by weight of the solid content of the composition.

Further, the composition of the present invention may contain a dye, a pigment, an adhesion aid, a storage stabilizer, an antifoaming agent and the like.

When a resist pattern is formed using the composition of the present invention, an alkali-soluble resin, compound (a), compound (b) and / or (c), and if necessary, the above-mentioned components are added. For example, various additives are dissolved in a solvent so that the solid content concentration becomes 20 to 40% by weight, and filtered with a filter having a pore size of about 0.2 μm.
Prepared as a solution. Therefore, the composition of the present invention is, in one aspect, a composition comprising an alkali-soluble resin, a compound (a), a compound (b) and / or (c), and the above-mentioned various additives optionally blended. And in another embodiment, a solution of the above composition in a solvent,
Must be understood.

The solvent used for preparing this solution is, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol. Monomethyl ether acetate, propylene glycol monopropyl ether acetate, toluene, xylene, methyl ethyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethoxy. Ethyl acetate, ethyl hydroxyacetate, 2-
Methyl hydroxy-3-methylbutyrate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3
-Ethyl ethoxypropionate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate and the like can be mentioned. Further, these solvents include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethylether, dihexyl. Ether, acetonylacetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol,
Benzyl alcohol, benzyl acetate, ethyl benzoate,
It can be used in combination with a high boiling point solvent such as diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, ethylene glycol monophenyl ether acetate.

The composition of the present invention prepared as a solution is
By coating method such as spin coating, cast coating, roll coating,
For example, a radiation-sensitive layer is formed by coating on a substrate such as a silicon wafer or a wafer coated with aluminum,
A pattern is formed by irradiating radiation through a predetermined mask pattern and developing with a developing solution. When the composition of the present invention is used as a positive resist, the composition is applied on a substrate, prebaked and irradiated with radiation, followed by heat treatment at 70 to 140 ° C., and then development. The effect of the present invention can be further improved.

The developer for the composition of the present invention is:
For example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine. , Tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo-
Alkaline compounds such as [5,4,0] -7-undecene and 1,5-diazabicyclo- [4,3,0] -5-nonane were dissolved to a concentration of, for example, 1 to 10% by weight. An alkaline aqueous solution is used. Further, a proper amount of a water-soluble organic solvent, for example, alcohol such as methanol or ethanol, or a surfactant can be added to the developer. When a developer containing such an alkaline aqueous solution is used, it is generally washed with water after development.

[0041]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Here, the measurement of Mw and the evaluation of various performances of the resist were performed by the following methods. Mw: GPC column (G2000H6: manufactured by Toso Co., Ltd.)
2 pieces, G3000H6: 1 piece, G4000H6: 1 piece)
Was measured by a gel permeation chromatograph method (GPC method) using monodisperse polystyrene as a standard under the analysis conditions of a liquid amount of 1.5 ml / min, an elution solvent of tetrahydrofuran, and a column temperature of 40 ° C. Dimensional fidelity: exposure time was changed using an NSR-1505i6A reduction projection exposure machine (lens numerical aperture: 0.50) manufactured by Nikon Corporation, and exposure was performed using i-line having a wavelength of 365 nm, and then tetramethylammonium hydroxy was used. Development was carried out at 25 ° C. for 60 seconds using an aqueous 2.4 wt% solution of water, and then washed and dried to form a positive resist pattern on the wafer. At that time, while reducing the mask dimension of the line and space pattern at 0.02 μm intervals, the line and space pattern of 0.5 μm is exposed at an exposure time for forming a 1: 1 width, and the resist line is exposed. The difference between the and-space pattern dimension and the mask design dimension was measured with a scanning electron microscope to obtain the difference between the pattern dimension and the mask design dimension. When the formed pattern dimension is within ± 10% of the mask design dimension, it is regarded as acceptable, and the minimum design dimension of the mask in the accepted pattern is defined as dimension fidelity. The smaller the minimum design dimension of this mask, the better the dimensional fidelity. Focus range: 0.5μ using scanning electron microscope
For the line-and-space pattern of m, the range of focus when the resolved pattern size is within ± 10% of the mask design size was defined as the focus range. The larger the focus range, the better the focus tolerance. Developability: The degree of scum and residual development was examined with a scanning electron microscope.

[Synthesis of Resin (A)] Synthesis Example 1 In a flask equipped with a stirrer, a condenser and a thermometer, m-
Cresol 69.2 g (0.64 mol), 2,3-xylenol 9.8 g (0.08 mol), 3,4-xylenol 9.8 g (0.08 mol), 37 wt% formaldehyde aqueous solution 38.5 g ( Formaldehyde: 0.47
5 mol) and 0.19 g of oxalic acid dihydrate (0.00
15 mol), then the flask is immersed in an oil bath,
The temperature of the reaction solution was kept at 100 ° C, and polycondensation was performed for 60 minutes while stirring. Then, m-cresol 17.3
g (0.16 mol) 2,3-xylenol 2.5 g
(0.02 mol), 2.5 g of 3,4-xylenol
(0.02 mol), 37 wt% formaldehyde aqueous solution 38.5 g (formaldehyde: 0.475 mol) and oxalic acid dihydrate 1.69 g (0.0135 mol) were added, and polycondensation was further performed for 150 minutes. It was Then
The oil bath temperature was raised to 180 ° C., and at the same time, the pressure inside the flask was reduced to 30 to 50 mmHg to remove water, oxalic acid, unreacted raw materials and the like. Then, the molten resin was cooled to room temperature and collected. This resin was dissolved in methyl 3-methoxypropionate at a solid content of 30% by weight, and 0.5 times amount of toluene and 0.4 times amount of n- were added to the weight of the resin solution. Hexane was added and the mixture was stirred and then left to stand. The lower layer (resin solution layer) separated into two layers by standing is taken out, concentrated, dehydrated and dried,
The novolac resin was recovered. This novolac resin is referred to as resin (A1). The Mw of the resin (A1) was 8,800.

Synthesis Example 2 69.2 g (0.6%) of m-cresol was placed in an autoclave.
4 mol), 9.8 g (0.08 mol) of 2,3-xylenol, 9.8 g (0.08 mol) of 3,4-xylenol, and 61.0 g of 37% by weight formaldehyde aqueous solution.
(Formaldehyde: 0.75 mol), oxalic acid dihydrate 6.3 g (0.05 mol), water 52.6 g and dioxane 182 g were charged, and then the autoclave was immersed in an oil bath and the temperature of the reaction solution was adjusted to 130. The temperature was kept at ° C and polycondensation was carried out for 8 hours under stirring. After the reaction, it was cooled to room temperature and the contents were taken out into a beaker. The lower layer separated into two layers in the beaker was taken out, concentrated, dehydrated and dried to recover the novolak resin. This novolac resin is referred to as resin (A2). The Mw of the resin (A2) was 7,800.

Synthesis Example 3 64.9 g (0.6 g) of m-cresol was placed in an autoclave.
Mol), 3,3-xylenol 36.7 g (0.3 mol), 3,4-xylenol 12.2 g (0.1 mol), 37 wt% formaldehyde aqueous solution 77.1 g
(Formaldehyde: 0.9 mol), oxalic acid dihydrate 6.3 g (0.05 mol), water 79.4 g and dioxane 383.9 g were charged, then the autoclave was immersed in an oil bath, and the temperature of the reaction solution was increased. Was maintained at 130 ° C, and polycondensation was carried out for 8 hours with stirring. After the reaction, it was cooled to room temperature and the contents were taken out into a beaker. The lower layer separated into two layers in the beaker was taken out, concentrated, dehydrated and dried to recover the novolak resin. This novolac resin is referred to as resin (A3). The Mw of the resin (A3) was 8,500.

[Synthesis of Resin (B)] Synthesis Example 4 m-cresol 64.8 g (0.60 mol) and p-cresol 4 were placed in the same flask as used in Synthesis Example 1.
3.2 g (0.40 mol), 37 wt% formaldehyde aqueous solution 24.3 g (formaldehyde: 0.30 mol) and oxalic acid dihydrate 0.30 g (0.0024)
Mol), then the flask was immersed in an oil bath, the temperature of the reaction solution was kept at 100 ° C., and polycondensation was carried out for 40 minutes under stirring. Then, in the same manner as in Synthesis Example 1, water, oxalic acid, unreacted raw materials, etc. were removed and cooled to recover the novolac resin. This novolac resin is referred to as resin (B1). The Mw of the resin (B1) was 800.

[Synthesis of Compound (b)] Here, (a-
1) is the formula

The compound (a-2) represented by the formula:

The compound (a-3) represented by the formula:

It is a compound represented by:

Synthesis Example 5 In a flask equipped with a stirrer, a dropping funnel and a thermometer,
27.2 g (0.1 mol) of the compound (a-1), 67.1 g (0.25 mol) of 1,2-naphthoquinonediazide-5-sulfonic acid chloride and 250 g of dioxane were charged under shading and while stirring. Dissolved. Then
The flask was immersed in a water bath maintained at a temperature of 30 ° C, and when the temperature of the reaction solution became constant at 30 ° C, 27.8 g (0.28 mol) of triethylamine was added to the solution, and the temperature of the reaction solution was 35%. It was gradually added using a dropping funnel so that the temperature did not exceed ° C. Then, the precipitated triethylamine hydrochloride was filtered off, and the filtrate was poured into a large amount of dilute hydrochloric acid to precipitate the product. The precipitated product was filtered and dried overnight in a heating vacuum dryer maintained at 40 ° C to obtain a compound (b-1).

Synthesis Example 6 27.2 g (0.1 mol) of compound (a-2), 1,2-
Naphthoquinonediazide-5-sulfonic acid chloride 67.
1 g (0.25 mol) and triethylamine 27.8
Compound (b-2) was obtained in the same manner as in Synthesis Example 5 except that g (0.28 mol) was used.

Synthesis Example 7 Compound (a-3) 30.0 g (0.1 mol), 1,2-
Naphthoquinonediazide-5-sulfonic acid chloride 67.
1 g (0.25 mol) and triethylamine 27.8
Compound (b-3) was obtained in the same manner as in Synthesis Example 5 except that g (0.28 mol) was used.

[Synthesis of Compound (c)] Synthesis Example 8 Resin (B1) 10.0 g, 1,2-naphthoquinonediazide-5-sulfonic acid chloride 13.9 g, dioxane 2
Compound (c-1) was obtained in the same manner as in Synthesis Example 5 except that 50 g and 5.75 g of triethylamine were used.

Synthesis Example 9 2,3,4-trihydroxybenzophenone 23.0 g
(0.1 mol), 1,2-naphthoquinonediazide-5-
Compound (c-2) was obtained in the same manner as in Synthesis Example 5 except that 69.9 g (0.26 mol) of sulfonic acid chloride and 28.9 g (0.29 mol) of triethylamine were used.

Synthesis Example 10 2,3,4,4'-tetrahydroxybenzophenone 2
Synthesis Example 5 except that 4.6 g (0.1 mol), 1,2-naphthoquinonediazide-5-sulfonic acid chloride 107.5 g (0.4 mol) and triethylamine 44.5 g (0.44 mol) were used. Compound (c-3) was obtained in the same manner as in.

Examples 1 to 6 and Comparative Examples 1 to 3 Resin (A) having a composition shown in Table 1 (where parts are parts by weight), a low molecular weight phenol compound or resin (B)
(*), The compound represented by the formula (1), the compound (c) and the solvent are mixed to form a uniform solution, and then the pore size is 0.2 μm.
The composition solution was prepared by filtering with a membrane filter of. The obtained solution was applied onto a silicon wafer having a silicon oxide film by using a spinner, and then 90
Pre-baking was performed for 2 minutes on a hot plate at ° C to form a resist film having a thickness of 1.2 µm, and various performance evaluations of the resist were performed. The evaluation results are shown in Table 2.

[0054]

[Table 1] In Table 1, the types of low molecular weight phenolic compounds and solvents are as follows. α: 1,1,1-tris (4-hydroxyphenyl)
Ethane β: 1,1-bis (4-hydroxyphenyl) -1-
Phenylethane S1: Ethylene glycol monoethyl ether acetate S2: Ethyl 2-hydroxypropionate S3: Methyl 3-methoxypropionate

[0055]

[Table 2] As is clear from Table 2, the composition of the present invention, which contains the compound represented by the general formula (1), has extremely excellent dimensional fidelity and focus tolerance as a positive resist. Further, the composition of the present invention had little scum as a resist and less development residue, good developability, and excellent pattern shape.

[0056]

As described above in detail, the radiation-sensitive resin composition of the present invention is a positive resist, which is particularly excellent in dimensional fidelity and focus tolerance and has good developability. It is also excellent in pattern shape. Therefore, it is extremely useful as a resist or the like for manufacturing an integrated circuit, which is expected to have higher integration in the future.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Takao Miura 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. An alkali-soluble resin and the following general formula (1): [In the general formula (1), X ^{1 to} X ⁹ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkoxy group or -OD.
A group (wherein D is a hydrogen atom or an organic group having a quinonediazide group) and R is a hydrogen atom or an alkyl group. However, at least one of X ^{1 to} X ⁹ is an —OD group. ] The radiation sensitive resin composition containing the compound represented by these, and when all D of General formula (1) is a hydrogen atom, it further contains the compound which has a quinonediazide group.