JPH11265065A - Radiation sensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a radiation sensitive resin composition having high resolution and good focus allowance and a rectangular resist pattern profile and restrained from occurrence of pattern defects after development by incorporating an alkali-soluble novolak resin and the quinonediazidosulfonic acid ester compound of a specified phenol compound. SOLUTION: The radiation sensitive resin composition contains the alkali- soluble novolak resin and the quinonediazidosulfonic acid ester compound of the phenol compound represented by formula I and/or II in which each of R1 -R9 is an H atom or a hydroxy or alkoxy or hydroxyalkoxy group; at least one of each group of R1 -R3 , R4 -R6 , and R7 -R9 is a hydroxyalkoxy group; each of A1 -A8 is an alkyl group; and each of B1 -B4 is, independently, an H atom or an alkyl group. The alkali-soluble novolak resin has an average molecular weight of, preferably, 2,000-20,000 in terms of polystyrene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a radiation-sensitive resin composition containing an alkali-soluble novolak resin. Particularly, the present invention relates to a positive-type radiation-sensitive resin composition suitable as a resist for producing a highly integrated circuit which is sensitive to ultraviolet rays and far ultraviolet rays.

[0002]

2. Description of the Related Art Positive resists are often used in the manufacture of integrated circuits because of their ability to provide high-resolution resist patterns. There is a demand for a positive resist composition having excellent properties such as depth of focus and developability.

In order to improve various properties of the positive resist composition, for example, in order to improve resolution, it is conceivable to increase the amount of a quinonediazide compound as one method. However, increasing the amount of the quinonediazide compound causes problems such as deterioration of developability, reduction of sensitivity, and deterioration of pattern shape. As another method, there is a method of increasing the aperture coefficient (NA) of the stepper, but in this case, the focus tolerance becomes narrow. As described above, when one of the performances is improved, there is a problem that the other performance is reduced. Accordingly, there is a need for a positive resist composition for producing highly integrated circuits that has a sufficient balance of characteristics such as resolution, focus tolerance, and developability. With the improvement in resolution, a dry etching method using plasma or reactive ions has been used instead of a conventional wet etching method using an etching solution such as hydrofluoric acid or nitric acid. At this time, if the resist pattern profile is a trapezoidal pattern (tapered shape), the resist film thickness at the bottom of the pattern is particularly small, so that it cannot withstand etching species (plasma, ions, etc.), and the dimensional value after etching varies. It may not be the design dimension value. For this reason, the rectangular cross section (pattern profile) of the resist pattern is more excellent in etching. Furthermore, in recent years, pattern defects such as (i) formation of a thin insolubilized layer at the upper part of the pattern after development, or (ii) occurrence of undeveloped residue at the lower part of the pattern, which contribute to a decrease in the yield of integrated circuits in recent years. Has also become a major problem, and its improvement is desired. for that reason,
There is a demand for a positive resist excellent in various characteristics such as high resolution, good focus tolerance and developability, and having a rectangular resist pattern profile and free from pattern defects.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a positive resist which has high resolution and good focus tolerance, has a rectangular resist pattern profile, and hardly causes pattern defects after development. An object of the present invention is to provide a conductive resin composition.

[0005]

As a result of intensive studies by the present inventors, it has been found that the above problems can be solved by using a quinonediazidesulfonic acid ester compound having a specific structure.

That is, the present invention provides (A) an alkali-soluble novolak resin, and (B) the following general formula (1):

[0007]

Embedded image [In the general formula (1), R _{1 to} R ₃ are the same or different and are a hydrogen atom, a hydroxyl group, an alkoxy group or a hydroxyalkoxy group, and at least one is a hydroxyalkoxy group. A _{1 to} A ₄ are alkyl groups. And / or the following general formula (2):

[0008]

Embedded image [In the general formula (2), R ₄ to R ₉ are the same or different and are a hydrogen atom, a hydroxyl group, an alkoxy group or a hydroxyalkoxy group, and at least one of R _{4 to} R ₆ and R _{7 to} R ₉ in each group. One is a hydroxyalkoxy group. A _{5 to} A ₈ are alkyl groups, and B _{1 to} B ₄ are
Independently, it is a hydrogen atom or an alkyl group. ] A radiation-sensitive resin composition comprising a quinonediazidesulfonic acid ester compound of a phenolic compound represented by the formula:

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. (A) Alkali-Soluble Novolak Resin The alkali-soluble novolak resin (hereinafter referred to as “resin (A)”) used as the component (A) in the present invention is obtained by condensing phenols and aldehydes in the presence of an acidic catalyst. There is no particular limitation on the resin obtained.

The phenols used in the resin (A) include, for example, phenol, o-cresol, m-cresol, p-cresol, 2,3-dimethylphenol,
2,4-dimethylphenol, 3,4-dimethylphenol, 2,5-dimethylphenol, 3,5-dimethylphenol, 2,3,5-trimethylphenol, 3,
4,5-trimethylphenol, resorcinol, 2-
Methylresorcinol, 4-ethylresorcinol, hydroquinone, methylhydroquinone, catechol, 4
-Methyl-catechol, pyrogallol, phloroglucinol, thymol, isothymol and the like. Among them, phenol, m-cresol, p-cresol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol, 3,4-
Dimethylphenol and 2,3,5-trimethylphenol are preferred. These phenols can be used alone or in combination of two or more. When two or more phenol compounds are used, the combination is not particularly limited. For example, two or more phenol compounds arbitrarily selected from the phenol compounds exemplified above can be combined.

Examples of aldehydes include formaldehyde, paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde,
Examples thereof include p-hydroxybenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, furfural, glyoxal, glutaraldehyde, terephthalaldehyde, and isophthalaldehyde. Among these, formaldehyde and o-hydroxybenzaldehyde can be particularly preferably used. These aldehydes can be used alone or in combination of two or more. The amount of the aldehyde used is preferably from 0.4 to 2 mol, more preferably from 0.6 to 1.5 mol, per 1 mol of the phenol. An acidic catalyst is usually used for the condensation reaction between phenols and aldehydes. Examples of the acidic catalyst include hydrochloric acid, sulfuric acid, formic acid, oxalic acid, methanesulfonic acid, p-toluenesulfonic acid and the like. The amount of these acidic catalysts used is usually from 1 × 10 ^{−5 to} 5 × 10
^-1 mole.

In the condensation reaction, for example, methanol,
It is desirable to use alcohols such as ethanol, propanol, butanol and propylene glycol monomethyl ether, cyclic ethers such as tetrahydrofuran and dioxane, ketones such as ethyl methyl ketone, methyl isobutyl ketone and 2-heptanone as a reaction medium. The amount of the reaction medium is usually 20 to 1,000 parts by weight per 100 parts by weight of the phenol as a reaction raw material. Although the temperature of the condensation reaction can be appropriately adjusted according to the reactivity of the raw materials, it is usually 10 to 200 ° C.

[0013] The reaction method is a method in which phenols, aldehydes, acidic catalysts, a reaction medium, and the like are charged all at once into a reaction vessel. An acid catalyst is charged in advance in a reaction vessel, and phenols, aldehydes and the like are added in the presence thereof. And the like can be appropriately adopted as the reaction proceeds.

As a method for recovering the formed resin (A), for example, after the completion of the condensation reaction, the reaction temperature is reduced to 13 in order to remove unreacted raw materials, acidic catalyst, reaction medium and the like existing in the system.
Raise to 0 ° C to 230 ° C and remove volatiles under reduced pressure;
A method for recovering the resin (A), the resin (A) obtained after the completion of the condensation reaction is treated with ethylene glycol monomethyl ether acetate, methyl 3-methoxypropionate, 2-heptanone, methyl isobutyl ketone, dioxane, methanol, ethyl acetate, etc. After dissolving in a good solvent, water, n-hexane, mixed with a poor solvent such as n-heptane to precipitate the resin (A), and then separated the solution layer of the precipitated resin (A),
There is a method of recovering the resin (A). In particular, according to the latter method, the fraction on the low molecular weight side of the resin (A) is removed, and the resin (A) having a relatively high molecular weight is obtained. Resin (A)
The polystyrene-equivalent weight average molecular weight (hereinafter referred to as “Mw”) of the composition of the present invention improves the workability when applying the composition of the present invention to a substrate, developability when used as a resist, sensitivity and heat resistance. From the viewpoint, it is preferably from 2,000 to 20,000, and particularly preferably from 3,000 to 15,000.

(B) Quinonediazidesulfonic acid esterification
Compound The quinonediazidesulfonic acid ester compound (hereinafter, referred to as "photosensitizer (B)") used as the component (B) in the composition of the present invention comprises a phenol compound represented by the above formula (1) and a phenol compound represented by the formula (1): It is a quinonediazide sulfonic acid ester compound of a compound selected from the group consisting of the phenol compounds represented by 2) (hereinafter referred to as "phenol compound (b)"). In the formulas (1) and (2), R ₁
To R ₉ are the same or different and are hydrogen atom, a hydroxyl group, an alkoxy group or a hydroxyalkoxy group, R ₁ ~
In each group of R ₃ , R _{4 to} R ₆ , and R _{7 to} R ₉ , at least one represents a hydroxyalkoxy group.

Here, the alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, and specific examples include a methoxy group, an ethoxy group, an n-propoxy group and an n-butoxy group. And a methoxy group is particularly preferred. Further, as the hydroxyalkoxy group, a hydroxyalkoxy group having 2 to 6 carbon atoms is preferable, and specific examples thereof include a 2-hydroxyethoxy group, a 3-hydroxypropoxy group, and a 4-hydroxybutoxy group. And a 2-hydroxyethoxy group is particularly preferable.

A _{1 to} A ₈ represent an alkyl group. Here, as the alkyl group, an alkyl group having 1 to 4 carbon atoms is preferable, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, and an n-butyl group. A methyl group is preferred. B _{1 to} B _{4 each} represent a hydrogen atom or an alkyl group. Here, as the alkyl group, those similar to the above-mentioned A _{1 to} A ₈ can be exemplified.

As specific examples of the phenol compound (b) represented by the formulas (1) and (2), the following formulas (3-1) to (3)
-13).

[0019]

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[0020]

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[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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[0029]

Embedded image The photosensitizer (B) is a quinonediazidesulfonic acid ester compound of the phenol compound (b), and specifically, 1,2-benzoquinonediazide-4-.
Sulfonate, 1,2-naphthoquinonediazide-
Examples thereof include 4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester, and 1,2-naphthoquinonediazide-6-sulfonic acid ester. Among them, 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester are preferable.

The photosensitizer (B) is, for example, a phenolic compound (b) and a 1,2-quinonediazidosulfonyl halide such as 1,2-naphthoquinonediazide-4-sulfonyl chloride and 1,2-naphthoquinonediazide-5-sulfonylchloride. Can be obtained by an esterification reaction of
In the esterification reaction, phenol compound (b) and 1,
The reaction ratio with 2-quinonediazidosulfonyl halide is 1,2-quinonediazidosulfonyl halide, preferably 0.2 to 1.0 mol, particularly preferably 1 mol to 1 mol of the phenolic hydroxyl group of the phenol compound (b). Is 0.4 to 1.0 mol. The reaction is carried out with a basic catalyst, for example, an aliphatic amine such as triethylamine,
The reaction is performed in the presence of a weakly basic organic compound such as an amine having a hetero ring such as pyridine. Particularly, triethylamine is preferable. The amount of the basic catalyst used is,
Equimolar to 1,2-quinonediazidosulfonyl halide
2.0-fold mol is preferred, and more preferably 1.1-
It is 1.3 times mol. As a solvent for the esterification reaction,
Dioxane, tetrahydrofuran, acetone, N, N-
Examples thereof include hydrophilic organic solvents such as dimethylformamide, dimethylsulfoxide, and N-methylpyrrolidone, and dioxane and acetone are particularly preferable. These solvents can be used alone or in combination of two or more. The amount of the solvent used is not particularly limited as long as the solvent can be stirred during the reaction, but usually the phenol compound (b) and 1,2 are used.
2 of the total weight with the quinonediazidosulfonyl halide
10 to 10 times is preferred. The reaction temperature and reaction time of the esterification reaction are not particularly limited as long as the esterification reaction proceeds quantitatively, but the reaction temperature is preferably 20 to 45 ° C. If the reaction temperature is lower than 20 ° C., the esterification reaction takes a long time, so that it is not efficient. If the reaction temperature exceeds 45 ° C., side reactions such as decomposition of a quinonediazide group may occur, which is not preferable. In the composition of the present invention, the photosensitive agent (B) is preferably used in a proportion of 5 to 50 parts by weight, particularly 10 to 40 parts by weight, per 100 parts by weight of the resin (A). The photosensitive agent (B) can be used alone or in combination of two or more.

Other Ingredients The composition of the present invention comprises the aforementioned ingredient (A) and ingredient (B)
In addition to the essential components described above, various types of components may be added alone or in combination of two or more, as needed, as long as the objects and effects of the present invention are not impaired. Examples of such components include the following.

[0032] For the purpose of accelerating alkali solubility of the solubility promoter wherein resin (A), the low molecular weight phenol compound (hereinafter, referred to as "solubility enhancers") may be added. As the dissolution promoter, a phenol compound having 2 to 5 benzene rings is suitable, and examples thereof include compounds represented by the following formulas (4-1) to (4-9).

[0033]

Embedded image [In the formulas (4-1) to (4-3), a and b are independently an integer of 0 to 3 (however, a and b are not simultaneously 0), and x and y are independently 0 to 3 And a + x ≦ 5 and b + y ≦ 5. ]

[0034]

Embedded image [In the formulas (4-4) and (4-5), a, b and c
Is independently an integer from 0 to 3 (but not simultaneously 0), x, y and z are each independently an integer from 0 to 3, and a + x ≦ 5, b + y ≦ 4, and c + z ≦ 5. ]

[0035]

Embedded image [In the formulas (4-6) to (4-8), a, b and c are each independently an integer of 0 to 3 (but not simultaneously 0);
x, y and z are independently a number from 0 to 3;
x ≦ 5, b + y ≦ 5, c + z ≦ 5. ]

[0036]

Embedded image [In the formula (4-9), a, b, c and d independently represent 0 to
An integer of 3 (but not simultaneously 0), p, q,
r and s are independently numbers from 0 to 3, and a + p ≦
5, b + q ≦ 5, c + r ≦ 5, and d + s ≦ 5. ]
The compounding amount of such a dissolution promoter is usually 100 (A).
It is 50 parts by weight or less per part by weight.

Photosensitizer (C) The composition of the present invention comprises a quinonediazidesulfonic acid ester compound other than the photosensitizer (B) (hereinafter referred to as "photosensitizer (C)").
) Can be added in a range that does not adversely affect the effects of the present invention. Specific examples of the photosensitive agent (C) include a 1,2-naphthoquinonediazidesulfonic acid ester compound having the following structure.

[0038]

Embedded image [Wherein, X _{1 to} X _{15 each} independently represent a hydrogen atom, a carbon atom 1
To 4 alkyl groups or hydroxyl groups. However, X ₁ ~
At least one in each group of X _5, X ₆ ~X ₁₀ and X ₁₁ to X ₁₅ is a hydroxyl group. ]

[0039]

Embedded image [Wherein, X _{16 to} X ₂₅ represent the same atoms or groups as those for X _{1 to} X ₁₅ , provided that at least one of X _{16 to} X _{20 represents}
One is a hydroxyl group. X _{26 to} X _{28 each} independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms,
And 4 is an alkoxy group or a hydroxyl group, at least one of which is a hydroxyl group. Y _{1 to} Y ₄ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ]

[0040]

Embedded image [Wherein, X _{29 to} X ₄₂ represent the same atoms or groups as X _{1 to} X ₁₅ , provided that X _{29 to} X ₃₂ , X _{33 to} X ₃₇ and X
At least one in each group of ₃₈ to X ₄₂ is a hydroxyl group. Y ₅ is an alkyl group having 1 to 4 carbon atoms. ]

[0041]

Embedded image [In the formula, X _{43 to} X ₄₈ represent the same atoms or groups as X 26 to X ₂₈ , provided that at least one of each group of X _{43 to} X ₄₅ and X _{46 to} X ₄₈ is a hydroxyl group. Also, Y
_{6 to} Y ₉ represent the same atoms or groups as Y _{1 to} Y ₄ . ]

[0042]

Embedded image [Wherein, X _{49 to} X ₆₈ represent the same atoms or groups as X _{26 to} X ₂₈ , provided that X _{49 to} X ₅₃ , X _{54 to} X ₅₈ , and X ₅₉
At least one of each of the groups X to X ₆₃ and X _{64 to} X ₆₈ is a hydroxyl group. Y ₁₀ is an alkyl group having 1 to 4 carbon atoms. ]

The amount of the photosensitive agent (C) is 10
It is 30 parts by weight or less per 0 parts by weight, and can be used alone or in combination of two or more. Also,
The total weight of 1,2-quinonediazidosulfonyl residues in the composition of the present invention is preferably 5 to 50% by weight, more preferably 1 to 50% by weight, based on the total solid content of the composition.
It is adjusted to be 0 to 30% by weight.

Other optional ingredients Additives such as surfactants can be incorporated. The surfactant is blended in order to improve the coating properties and developability of the composition, and the amount of the surfactant is 10% of the solid content of the composition.
It is 2 parts by weight or less per 0 parts by weight. Dyes and pigments can be compounded to visualize the latent image of the radiation-irradiated part of the resist and reduce the effects of halation at the time of radiation irradiation, and an adhesive aid is added to improve adhesion. Can also. Further, if necessary, a storage stabilizer,
An antifoaming agent or the like can also be added. Solvent The composition of the present invention usually contains a solvent and is often used in the form of a solution. Such a composition is prepared by dissolving the other components in a solvent such that the solid content concentration becomes, for example, 20 to 40% by weight, and filtering the obtained solution through a filter having a pore size of about 0.2 μm. Is done.

Examples of the solvent used include 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, and propylene glycol. Monomethyl ether acetate, propylene glycol monopropyl ether acetate, xylene, methyl ethyl ketone, 2-heptanone, 3-heptanone,
-Heptanone, cyclohexanone, ethyl lactate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-hydroxy-3
Examples thereof include methyl-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethyl acetate, butyl acetate, methyl pyruvate, and ethyl pyruvate. Further, N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylformamide
Methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, ethylene A high boiling point solvent such as glycol monophenyl ether acetate can also be added. These solvents are used alone or in combination of two or more.

The composition of the present invention prepared as a solution for forming a resist film is applied to a silicon wafer or a wafer coated with aluminum or the like by spin coating, casting coating, roll coating or the like. Next, a resist film is formed by pre-baking the resist film, and the resist film is irradiated with radiation so as to form a desired resist pattern, and is developed with a developer to form a pattern. As the radiation used at this time, ultraviolet rays such as g-rays and i-rays are preferably used, and various radiations such as charged ultraviolet rays such as far ultraviolet rays such as excimer laser, X-rays such as synchrotron radiation, and electron beams are used. You can also. In addition, the composition of the present invention forms a resist film, performs prebaking and irradiation, performs an operation of heating at 70 to 140 ° C. (hereinafter, referred to as “postbaking”), and then performs development. The effect of the present invention can be further improved.

Examples of the developing solution used for the resist film include 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, , 8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4.3.0] -5-nonane, etc., at a concentration of, for example, 1 to 10% by weight. An alkaline aqueous solution dissolved in water is used.
Further, a suitable amount of a water-soluble organic solvent, for example, an alcohol such as methanol or ethanol or a surfactant may be added to the developer. When a developer composed of such an alkaline aqueous solution is used, it is generally washed with water after development.

[0048]

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 (G2000HXL: 2
Gel permeation chromatograph using monodisperse polystyrene as a standard under the analysis conditions of flow rate: 1.0 ml / min, eluting solvent: tetrahydrofuran, column temperature: 40 ° C., using G3000HXL: 1, G4000HXL: 1). It was measured by the method. Resolution: 0.35 μm line and space (L /
S) The minimum amount of the L / S pattern to be separated without reducing the film thickness was measured with a scanning electron microscope at the exposure amount (appropriate exposure amount) when the pattern was resolved one-to-one. Developability: A resist film of the composition was formed, and the scum after pattern formation and the extent of undeveloped portions were examined using a scanning electron microscope. Focus tolerance: Using a scanning electron microscope, at a proper exposure dose, the deviation of the focus when the resolved pattern dimension is within ± 10% of the mask design dimension is defined as a focus range and used as an evaluation index. . A large focus range means that it has good focus tolerance. Pattern shape: One-to-one L / S pattern of 0.35 μm
The cross section of the above pattern of 0.35 μm was observed with a scanning electron microscope. As shown in FIG. 1, the angle between the resist side wall and the substrate (hereinafter, referred to as “side wall angle”) was measured. The closer the side wall angle is to 90 °, the better the pattern shape. Pattern Defects: The wafers coated, exposed and developed as described above were examined for the number of defects of 0.2 μm or more using a KLA-2112 wafer appearance inspection device manufactured by KLA.

<Synthesis of Resin (A)> Synthesis Example 1 172.8 g (1.6 mol) of m-cresol was placed in a 2 L separable flask equipped with a condenser and a stirrer.
36.6 g (0.3 mol) of 3-dimethylphenol,
12.4 g (0.1 mol) of 3,4-dimethylphenol, 371.6% by weight aqueous solution of formaldehyde 121.6
g (formaldehyde: 1.5 mol), 12.6 g (0.1 mol) of oxalic acid dihydrate and 554 g of methyl isobutyl ketone, and the mixture was condensed for 8 hours while stirring while maintaining the internal temperature at 90 to 100 ° C. Was done. The obtained reaction solution was washed twice with 500 g of ion-exchanged water, 554 g of n-heptane was added, and the mixture was stirred for 30 minutes and left to stand for 1 hour.
The upper layer separated into two layers is removed by decantation, ethyl lactate is added to the lower layer, and the remaining methyl isobutyl ketone, n-heptane and water are removed by concentration under reduced pressure to obtain an ethyl lactate solution of the novolak resin (A-1). Was. Mw of this resin (A-1) was 8,600.

Synthesis Example 2 A phenol component and an aldehyde component charged in a separable flask were mixed with 48.8 g of 2,5-dimethylphenol.
(0.4 mol), 151.2 g of m-cresol (1.
4 mol), p-cresol 21.6 g (0.2 mol), 37% by weight aqueous formaldehyde solution 120.0
g (formaldehyde: 1.4 mol)
The same operation as in Synthesis Example 1 was performed, and the novolak resin (A-
An ethyl lactate solution of 2) was obtained. Mw of the resin (A-2) was 8,300.

Synthesis Example 3 In a 1 L autoclave, 64.9 g of m-cresol was added.
(0.6 mol), 2,3-dimethylphenol 36.
6 g (0.3 mol), 13.6 g (0.1 mol) of 2,3,5-trimethylphenol, 64.9 g of a 37% by weight aqueous solution of formaldehyde (formaldehyde: 0.8
0 mol), 6.3 g (0.05 mol) of oxalic acid dihydrate and 384 g of dioxane were charged, the autoclave was immersed in an oil bath, the temperature of the reaction solution was kept at 130 ° C., and the mixture was stirred for 8 hours. Done. Thereafter, the mixture was cooled to room temperature, the contents were taken out into a beaker, and the separated lower layer (resin layer) was separated. This resin layer was concentrated and dehydrated, and dissolved in ethyl lactate to obtain a solution of novolak resin (A-3).
Mw of the resin (A-3) was 7,100.

Synthesis Example 4 64.9 g of m-cresol was placed in a 1-liter autoclave.
(0.6 mol), 2,3-dimethylphenol 12.
2 g (0.1 mol), 2,4-dimethylphenol 3
6.6 g (0.3 mol), 37% by weight aqueous formaldehyde solution 60.0 g (formaldehyde: 0.74 mol), p-toluenesulfonic acid monohydrate 5.7 g
(0.03 mol) and methyl isobutyl ketone 28
After charging 5 g, the autoclave was immersed in an oil bath, the temperature of the reaction solution was kept at 130 ° C., the mixture was stirred, and condensation was performed for 6 hours. Then, cool to room temperature, 500m of ion exchange water
3 times with water, and 400 mL of n-heptane was added thereto for 3 hours.
Stirred for 0 minutes. After allowing to stand for 1 hour, the upper layer separated into two layers was removed by decantation, and ethyl lactate was added to the lower layer, and residual methyl isobutyl ketone, n-heptane,
The water was removed by concentration under reduced pressure to obtain an ethyl lactate solution of the novolak resin (A-4). Mw of the resin (A-4) is 7,60
It was 0.

<Quinonediazidesulfonic acid ester compound
Synthesis of product> In the following, the above-mentioned formulas (3-1) and (3-
2), the compounds represented by (3-5) and (3-6)
Compounds (3-1), (3-2), (3-5), (3
-6). Synthesis Example 5 Under light shielding, a filter equipped with a stirrer, dropping funnel and thermometer
In Lasco, 49.4 g of compound (3-1) (0.10
), 1,2-naphthoquinonediazide-5-sulfonic acid
48.4 g (0.18 mol) of chloride and dioxa
Then, 587 g of the compound was charged and dissolved with stirring. About
Immerse the flask in a water bath controlled at 30 ° C.
When the internal temperature became constant at 30 ° C, the solution was
Ethylamine 20.2g (0.20mol)
Add using a dropping funnel so that the temperature does not exceed 5 ° C.
For 2 hours. Then, the precipitated hydrochloride is filtered.
, And the filtrate was washed with 5.3 L of a 0.05% hydrochloric acid aqueous solution.
The reaction product was precipitated by pouring into the mixture, filtered and washed with water.
And dried in a vacuum oven at 40 ° C for 24 hours.
Thus, a didosulfonic acid ester compound (B-1) was obtained.

Synthesis Example 6 Compound (3-2) Instead of Compound (3-1)
The same procedure as in Synthesis Example 5 was repeated except that 1 g (0.10 mol) of the dioxane was changed to 561 g, and the quinonediazidesulfonic acid ester compound (B-
2) was obtained. Synthesis Example 7 Compound (3-5) was used in place of compound (3-1).
8 g (0.05 mol), and the amount of 1,2-naphthoquinonediazide-5-sulfonic acid chloride was 25.5 g.
(0.095 mol) and the amount of triethylamine used was 1
0.6 g (0.10 mol) of dioxane was used in an amount of 4
A quinonediazidesulfonic acid ester compound (B-5) was obtained in the same manner as in Synthesis Example 5 except that the amount was changed to 34 g.

Synthesis Example 8 Compound (3-6) was used in place of compound (3-1).
4 g (0.05 mol), and the amount of 1,2-naphthoquinonediazide-5-sulfonic acid chloride was 25.5 g.
(0.095 mol) and the amount of triethylamine used was 1
0.6 g (0.10 mol) of dioxane was used in an amount of 4
A quinonediazidesulfonic acid ester compound (B-6) was obtained in the same manner as in Synthesis Example 5 except that the amount was changed to 07 g. Synthesis Example 9 In a light-shielded flask equipped with a stirrer, a dropping funnel and a thermometer, the following formula (* 1):

[0056]

Embedded image 17.4 g (0.05 mol) of the compound represented by (* 1),
2-naphthoquinonediazide-5-sulfonic acid chloride
40.3 g (0.15 mol) and 346 g of acetone
And dissolved with stirring. Then, the flask was immersed in a water bath controlled at 30 ° C.
When the temperature became constant at 0 ° C, a solution prepared by dissolving 19.5 g (0.16 mol) of triethylamine in 40 g of acetone was added to the solution using a dropping funnel so that the internal temperature did not exceed 35 ° C. The reaction was performed for 2 hours. Thereafter, the precipitated hydrochloride was removed by filtration, and the filtrate was diluted with 4 L of 0.1%.
The reaction product was precipitated by pouring into an aqueous solution of hydrochloric acid, filtered, washed with water, and dried in a vacuum dryer at 40 ° C. overnight to obtain a quinonediazidesulfonic acid ester compound (C-1).

Synthesis Example 10 Instead of the compound represented by the formula (* 1), the following formula (*)
2):

[0058]

Embedded image Using 19.6 g (0.05 mol) of the compound represented by (* 2), the amount of 1,2-naphthoquinonediazide-5-sulfonic acid chloride was changed to 24.2 g (0.09 mol), and acetone was added. Was changed to 262 g, and a quinonediazidesulfonic acid ester compound (C-2) was obtained in the same manner as in Synthesis Example 9. Synthesis Example 11 Instead of the compound represented by the formula (* 1), the following formula (*
3):

[0059]

Embedded image Using 19.6 g (0.05 mol) of the compound represented by (* 3), the amount of 1,2-naphthoquinonediazide-5-sulfonic acid chloride was reduced to 21.5 g (0.08 mol), and acetone was added. Was changed to 345 g, and a quinonediazidesulfonic acid ester compound (C-3) was obtained in the same manner as in Synthesis Example 9.

Example A resin (A), a dissolution promoter, a quinonediazide sulfonic acid ester compound and a solvent were mixed with the composition shown in Table 1 (parts are parts by weight) to obtain a homogeneous solution.
The solution was filtered through a membrane filter having a pore size of 0.2 μm to prepare a solution of the composition. The obtained solution was applied on a silicon wafer having a silicon oxide film using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes to form a resist film having a thickness of 0.86 μm.
Then, through a reticle, NSR-
2005i9C reduction projection exposure machine (lens numerical aperture = 0.5
After exposure at 7) using a wavelength of 365 nm (i-line) and post-baking at 110 ° C. for 1 minute on a hot plate,
The resist was developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide, rinsed with ultrapure water, and dried to form a resist pattern. The obtained resist pattern was examined, and the characteristics of the composition of each example as a resist pattern were evaluated. Table 2 shows the results.

In Table 1, the types of the dissolution promoter and the solvent are as follows. Dissolution promoter α: 1,1-bis (2,5-dimethyl-4-hydroxyphenyl) acetone β: 4,6-bis [1- (4-hydroxyphenyl)-
1-methylethyl] -1,3-dihydroxybenzene Solvent S1: Ethyl 2-hydroxypropionate S2: Ethyl 3-ethoxypropionate S3: 2-Heptanone

[0062]

[Table 1]

[0063]

[Table 2]

[0064]

According to the radiation-sensitive resin composition of the present invention, the generation of scum is effectively controlled, the resolution is high, the focus tolerance is good, the pattern profile of the resist is rectangular, and pattern defects after development are eliminated. It is unlikely to occur. Therefore, this composition can be suitably used as a positive resist for producing an integrated circuit having a high degree of integration.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a cross-sectional shape and a side wall angle of a resist pattern.

Claims (1)

[Claims] (A) an alkali-soluble novolak resin,
And (B) the following general formula (1): [In the general formula (1), R _{1 to} R ₃ are the same or different and are a hydrogen atom, a hydroxyl group, an alkoxy group or a hydroxyalkoxy group, and at least one is a hydroxyalkoxy group. A _{1 to} A ₄ are alkyl groups. And / or the following general formula (2): [In the general formula (2), R ₄ to R ₉ are the same or different and are a hydrogen atom, a hydroxyl group, an alkoxy group or a hydroxyalkoxy group, and at least one of R _{4 to} R ₆ and R _{7 to} R ₉ in each group. One is a hydroxyalkoxy group. A _{5 to} A ₈ are alkyl groups, and B _{1 to} B ₄ are
Independently, it is a hydrogen atom or an alkyl group. A radiation-sensitive resin composition comprising a quinonediazidesulfonic acid ester compound of a phenolic compound represented by the formula: