JPH04299348A - Radiation sensitive resin composition - Google Patents

Abstract

PURPOSE:To suppress the generation of scum and to obtain a high sensitivity and high resolution as well as to improve developability, heat resistance, residual film rate, etc., by incorporating an alkali-soluble resin, at least one kind of two kinds of specific compds. and 1,2-quinonediazide compd. into the above compsn. CONSTITUTION:The alkali-soluble resin, at least one kind of the compd. expressed by formula I or II and the 1,2-quinonediazide compd. are incorporated into this compsn. In the formula I, X<1> to X<13> denote any of a hydrogen atom, alkyl group, alkoxy group or hydroxyl group; Y<1> to Y<4> denote a hydrogen atom or alkyl group; R<1> denotes a hydrogen atom, -COOR<2> (R<2> is a hydrogen atom, alkyl group, aryl group). In the formula II, X<14> to X<18> denote a hydrogen atom, alkyl group, alkoxy group or hydroxyl group. The alkali-soluble resin includes, for example, a novolak resin, resol resin, polyvinyl phenol or its deriv., etc., and the novolak resin is particularly preferably used.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to a radiation-sensitive resin composition containing an alkali-soluble resin, and more specifically to radiation-sensitive resin compositions containing an alkali-soluble resin, and more particularly to radiation-sensitive resin compositions containing an alkali-soluble resin. The present invention relates to a radiation-sensitive resin composition suitable as a resist for producing highly integrated circuits sensitive to radiation such as beams.

0002

[Prior Art] Positive resists are often used in the manufacture of integrated circuits because they can provide resist patterns with high resolution. A positive resist that can form patterns is desired. In other words, when forming a fine resist pattern using a positive resist, when developing a latent image formed by radiation irradiation with a developer consisting of an alkaline aqueous solution, the portion where the radiation irradiation area is in contact with the wafer (the bottom of the pattern) is ).

0003

[Problems to be Solved by the Invention] However, in the case of conventional positive resists, when the interval between resist patterns to be formed is less than 0.8 μm, development residue called scum tends to occur, causing problems in developability. Ta. Furthermore, as the degree of integration of integrated circuits increases, the wafer etching method is shifting from the conventional wet etching with large side etching to dry etching with small side etching. In this dry etching, it is important that the resist pattern does not change during etching, so it is necessary to have good heat resistance. Furthermore, as the degree of integration increases, there is a demand for improved throughput during the production of integrated circuits, and a resist with high sensitivity is required. Therefore, an object of the present invention is to effectively suppress the generation of scum, have excellent developability, and have high sensitivity and
It is an object of the present invention to provide a radiation-sensitive resin composition suitable as a positive resist having high resolution and excellent heat resistance, residual film rate, etc.

0004

[Means for Solving the Problems] According to the invention, an alkali-soluble resin (hereinafter referred to as "resin A"), which has the following general formula (
1);

[Formula 1] In the formula, X1 to X13 represent a hydrogen atom, an alkyl group, an alkoxy group or a hydroxyl group, and X1 to X5, X6 to X8 and X9
At least 1 in each combination of ~X13
hydroxyl groups are included, Y1 ~
Y4 represents a hydrogen atom or an alkyl group, and R1
is a hydrogen atom -COOR2 (R2 represents a hydrogen atom, an alkyl group, or an aryl group), or the following general formula (
2) Represents a group represented by (X14 to X18 represent a hydrogen atom, an alkyl group, an alkoxy group, or a hydroxyl group)

Provided is a radiation-sensitive resin composition containing at least one compound represented by the formula (hereinafter referred to as compound (A)) and a 1,2-quinonediazide compound. .

Alkali-soluble resin The "resin (A)" used in the present invention includes, for example, novolak resin, resol resin, polyvinylphenol or its derivatives, styrene-maleic anhydride copolymer, polyvinyl hydroxybenzoate, carboxyl group-containing ( Examples include meth)acrylic acid resins, and novolak resins are particularly preferred. Among novolak resins, those obtained by polycondensing phenols represented by the following formula (3) and aldehydes are particularly suitable.

[Chemical formula 3] In the formula, n represents an integer of 1 to 3.

Examples of the above phenols include o-cresol, m-cresol, p-cresol, 2,3
-xylenol, 2,4-xylenol, 2,5-
Xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,4-
Examples include trimethylphenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, among others o-cresol, m-cresol, p-cresol, 2,5-xylenol, 3,5
-xylenol and 2,3,5-trimethylphenol are preferred, more preferably m-cresol/
3,5-xylenol/p-cresol = 95/5/
0-20/80/75, m-cresol/2,3,5
-trimethylphenol/p-cresol = 95/5/
It is a combination system of 0 to 30/70/65 (molar ratio).

Examples of aldehydes to be polycondensed with the above phenols include formaldehyde, trioxane, paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, and 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 include p-n-butylbenzaldehyde and furfural, with formaldehyde being particularly preferred. In this case, hemifomals such as trioxane, paraformaldehyde, methyl hemiformal, ethyl hemiformal, propyl hemiformal, butyl hemiformal, and phenyl hemiformal can be used as the formaldehyde generating source. These aldehydes can also be used alone or in combination of two or more. The amount of the aldehyde used is preferably 0.7 to 3 mol, more preferably 0.8 to 1.5 mol, per 1 mol of phenol.

[0008] An acidic catalyst is usually used for polycondensation of phenols and aldehydes. Examples of the acidic catalyst include hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, and acetic acid. The amount of these acidic catalysts used is usually
1 x 10-5 to 5 x 10-5 per mole of phenols
It is 1 mole.

In polycondensation, water is usually used as a reaction medium, but if the phenols used in polycondensation do not dissolve in the aqueous solution of aldehydes and the reaction becomes a heterogeneous system from the initial stage, water may be used as the reaction medium. Hydrophilic solvents can also be used. 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 these reaction media used is usually 20 to 100 parts by weight of the reaction raw material.
It is 1000 parts by weight. The temperature of polycondensation can be adjusted as appropriate depending on the reactivity of the reaction raw materials, but usually 1
The temperature is 0 to 200°C, preferably 70 to 130°C. Polycondensation methods include phenols, aldehydes,
It is possible to adopt a method in which the acidic catalyst and the like are added all at once, and a method in which phenols, aldehydes, etc. are added as the reaction progresses in the presence of the acidic catalyst. After the completion of polycondensation, the temperature of the reaction system is generally lowered to 1 to remove unreacted raw materials, acidic catalyst, reaction medium, etc. present in the system.
30-230 °C and under reduced pressure, e.g.
Resin (A) obtained by distilling off volatile components at about 0 mmHg
Collect.

The polystyrene equivalent weight average molecular weight (hereinafter referred to as "Mw") of the resin (A) used in the present invention is preferably from 2,000 to 20,000, preferably from 3,000 to 15,000. It is even more preferable that there be. When Mw exceeds 20,000, it may be difficult to uniformly apply the composition of the present invention to a wafer, and furthermore, developability and sensitivity tend to decrease,
Moreover, when Mw is less than 2,000, there is a tendency for heat resistance to decrease. In addition, in order to obtain resin (A) with a high Mw, the resin obtained above is dissolved in a good solvent such as ethyl cellosolve acetate, dioxane, methanol, or ethyl acetate, and then dissolved in water, n-hexane, n- What is necessary is to mix a poor solvent such as heptane, then separate the precipitated resin solution layer, and recover the resin (A).

In the present invention, a low molecular weight phenol compound can also be used as a solubility promoter for the purpose of promoting the alkali solubility of the resin (A). As this low molecular weight phenol compound, a phenol compound having about 2 to 6 benzene rings is suitable, and although it is not particularly limited, a compound represented by the following formula (4) can be exemplified. .

embedded image In the formula, a, b and c are each a number from 0 to 3, and (
However, if all are 0), x, y and z are
It is a number from 0 to 3. The amount of such a low molecular weight phenol compound is usually 50 parts by weight per 100 parts by weight of the resin (A).
Part by weight or less.

[0012] For the same purpose as above, a low molecular weight alkali-soluble novolak resin or alkali-soluble resol resin (hereinafter simply referred to as "resin (B)") can also be used as a solubility promoter. Here, the resin (B) is obtained by polycondensation of phenols and aldehydes.
In addition to those exemplified as phenols used in the synthesis of A), phenol, 1-naphthol, 2-naphthol, etc. can be used. Furthermore, as the aldehydes, those used in the synthesis of the resin (A) can be used. The amount of aldehydes used is phenols 1
It is preferably 0.1 to 3 moles, more preferably 0.2 to 1.5 moles. In this polycondensation, an alkaline catalyst can also be used in addition to the acidic catalyst used in the polycondensation of the resin (A). Resin (B)
The Mw of is usually preferably 10,000 or less, more preferably 200 to 2,000, particularly preferably 300 to 1,000. Such resins (B) include phenol/formaldehyde condensed novolak resin, m-cresol/formaldehyde condensed novolak resin, p-cresol/formaldehyde condensed novolak resin, and o-cresol/formaldehyde condensed novolak resin.
Examples include formaldehyde condensed novolak resins, m-cresol/p-cresol/formaldehyde condensed novolak resins, and the like. The blending amount of such resin (B) is generally 60 parts by weight per 100 parts by weight of resin (A).
Part by weight or less.

Compound (A) In the composition of the present invention, the compound (A) has the above-mentioned general formula (1), that is,

At least one compound (A) represented by Formula 1 is blended.

In this general formula (1), X1 to X1
3 is a group selected from a hydrogen atom, an alkyl group, an alkoxy group, and a hydroxyl group, and X1 to
It is necessary that each combination of X5, X6 to X8 and X9 to X13 contains at least one hydroxyl group. That is, each benzene ring is substituted with at least one hydroxyl group.

[0015] Here, the alkyl group preferably has 4 or less carbon atoms, and specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group,
A t-butyl group can be exemplified. Further, as the alkoxy group, an alkoxy group having a carbon number of 4 or less is preferable, and specific examples thereof include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and the like.

Furthermore, in the general formula (1), Y1 to Y4
represents a hydrogen atom or an alkyl group, and the alkyl group is preferably a lower alkyl group having 4 or less carbon atoms, as in the case of X1 to X13 above.

Furthermore, R1 is a hydrogen atom, -COOR2
(R2 represents a hydrogen atom, an alkyl group, or an aryl group) or a group represented by the general formula (2) described above. In relation to this R2, as the alkyl group, the above-mentioned X
As in the case of 1 to X13, an alkyl group having 4 or less carbon atoms is preferable, and as the aryl group, one having 6 to 10 carbon atoms such as a phenyl group, tolyl group, xylyl group, and naphthyl group is preferable. Also, in relation to general formula (2),
14 to X18 are the same as X1 to X13 above, but
These do not necessarily need to contain hydroxyl groups.

The compound represented by the general formula (1) (A
) can include a compound represented by the following formula (5).

[C5]

[C6]

[C7]

[Chemical formula 8]

[Chemical formula 9]

[Chemical formula 10]

[Chemical formula 11]

[Chemical formula 12]

[Chemical formula 13]

The compound (A) represented by the above formula (5) can be synthesized, for example, by condensing hydroxybenzyl alcohols and phenol compounds using an acid catalyst.

In the present invention, the above-mentioned compound (A)
is 0.5 to 100 per 100 parts by weight of resin (A)
It is preferred to use it in a proportion of 2 to 50 parts by weight, particularly 2 to 50 parts by weight.

1,2-quinonediazide compound In the present invention, in addition to resin (A) and compound (A), 1,2-quinonediazide compound
- A quinonediazide compound is blended. Like this 1
,2-quinonediazide compounds include, for example, 1,2
-benzoquinonediazide-4-sulfonic acid ester,
Examples include 1,2-quinonediazide sulfonic acid esters such as 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester, and the following can be exemplified. 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)-1-phenylethane, 1,1-bis(4-hydroxyphenyl)-
4-[1-(4-hydroxyphenyl)-1-methylethyl]-1-phenylethane, 2,4,4-trimethyl-2',4',7-trihydroxy-2-phenylflavan, 1,1 , 3-tris(4-hydroxyphenyl)butane, 1,1,3-tris(2,5-dimethyl-4-hydroxyphenyl)propane, etc.
-Besizoquinonediazide-4-sulfonic acid ester, 1
, 2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester, the hydrogen atoms of the hydroxyl groups of the resin (B) mentioned above, for example, 0.20 to 1 mol per hydrogen atom, Preferably, 1,2-quinonediazide sulfonic acid ester substituted with 1,2-naphthoquinonediazide-5-sulfonyl group in a proportion of 0.40 to 1 mole.

In the composition of the present invention, the amount of the 1,2-quinonediazide compound is usually 3 to 100 parts by weight, preferably 5 to 100 parts by weight, based on 100 parts by weight of the resin (A).
It is 50 parts by weight.

Various compounding agents Various compounding agents such as sensitizers and surfactants can be added to the composition of the present invention. A sensitizer is added to improve the sensitivity of the composition, and examples of such a sensitizer include 2H-pyrido-(3,2
-b) -1,4-Oxazin-3(4H)-ones, 10H-pyrido-(3,2-b)-(1,4)-benzothiazines, urazoles, hydantoins, parbituric acids, glycine anhydride 1-hydroxybenzotriazoles, alloxanes, maleimides, and the like. The blending amount of these sensitizers is as follows: Resin (A) 1
00 parts by weight, it is usually 50 parts by weight or less.

[0024] Furthermore, surfactants are added to improve the coating properties and developability of the composition, and examples of such surfactants include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, etc. ,
Polyoxyethylene oleyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate, FTOP EF301, EF303, EF352 (
Product name (manufactured by Shin-Akita Kasei Co., Ltd.), Megafax F171
, F172, F173 (product name, manufactured by Dainippon Ink Company), Florado FC430, FC431 (product name, manufactured by Sumitomo 3M Company), Asahi Guard AG710,
Surflon S-382, SC-101, SC-
102, SC-103, SC-104, SC-1
05, SC-106 (trade name, manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid-based or methacrylic acid-based (co-)
Heavy body polyflow No. 75, No. 95 (trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.). The blending amount of these surfactants is usually 2 parts by weight or less per 100 parts by weight of the solid content of the composition.

Furthermore, dyes and pigments can be added to the composition of the present invention in order to visualize the latent image in the radiation irradiated area and to reduce the effect of halation during radiation irradiation, and also to improve adhesion. In order to do this, an adhesion aid may be added. Furthermore, storage stabilizers, antifoaming agents, etc. can be added as necessary.

Preparation of Composition and Pattern Formation The composition of the present invention contains the resin (A), the compound (A), the 1,2-quinonediazide compound, and the various compounding agents described above at a solid content of, for example, 20%. It is prepared by dissolving it in a solvent to a concentration of ~40% by weight and filtering it through a filter with a pore size of about 0.2 μm.

Examples of the solvent used in this case include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol methyl ether acetate, propylene glycol propyl Aromatic hydrocarbons such as ether acetate, toluene, xylene, methyl ethyl ketone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-hydroxy-3- Methyl butanoate, 3
-Methyl methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl acetate, and butyl acetate can be used. Furthermore, N
-Methylformamide, N,N-dimethylformamide, N-methylformanilide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethyl ether, dihexyl ether, acetonyl acetone,
Isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate, etc. It is also possible to add boiling point solvents.

The composition of the present invention is applied to a silicon wafer or a wafer coated with aluminum or the like by spin coating, flow coating, roll coating, etc. to form a radiation-sensitive layer, and then applied to a predetermined mask. A pattern is formed by irradiating the radiation-sensitive layer with radiation through the pattern and developing it with a developer. Furthermore, when using the composition of the present invention as a positive resist,
The effects of the present invention can be further improved by applying the composition onto a wafer, etc., pre-baking and irradiating it with radiation, heating it at 70 to 140°C, and then developing it. .

Developer Solution Examples of the developer solution for the composition of the present invention include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, and diethylamine. -n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine,
Tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo-(5,4,0)-7
-undecene, 1,5-diazabicyclo-(4,3,
An alkaline aqueous solution prepared by dissolving an alkaline compound such as 0)-5-nonane to a concentration of, for example, 1 to 10% by weight is used. Further, a suitable amount of a water-soluble organic solvent such as alcohols such as methanol and ethanol, or a surfactant may be added to the developer. In addition, when development is performed using a developer made of such an alkaline aqueous solution, rinsing with water is generally performed subsequently.

[0030]

EXAMPLES The present invention will be explained in detail below with reference to Examples, but the present invention is not limited in any way by these Examples. In addition, the measurement of Mw and the evaluation of resist in Examples were performed by the following method.

Mw: GPC column manufactured by Toyo Soda Co., Ltd. (G2
000H6 2 pieces, G3000H6 1 piece, G4000
H6 (1 bottle) under the analysis conditions of a flow rate of 1.5 ml/min, elution solvent tetrahydrofuran, and column temperature of 40 °C.
It was measured by gel permeation chromatography using monodisperse polystyrene as a standard.

Sensitivity: Nikon Corporation-NSR-1505i6
A: Varying the exposure time using a reduction projection exposure machine (numerical aperture of the lens: 0.45), exposure was performed using i-line with a wavelength of 365 nm, and then a 2.4% by weight aqueous solution of tetramethylammonium hydroxide was used as a developer. used, 25℃
The resist pattern was developed on the wafer for 60 seconds, rinsed with water, and dried to form a resist pattern on the wafer.The exposure time (hereinafter referred to as This is called the "optimal exposure time"
) was sought.

Resolution: The dimension of the smallest resist pattern that was resolved when exposed at the optimum exposure time was measured.

Remaining film rate: The thickness of the pattern after development at the optimum exposure 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 degree of scum and development residue was examined.

Heat resistance: A wafer with a resist pattern formed thereon was placed in a clean oven, and the temperature at which the pattern began to collapse was measured.

Pattern shape: Using a scanning electron microscope,
The lower side A and upper side B of the rectangular cross section of the 0.6 μm resist pattern after development were measured, and the pattern shape was determined to be good if 0.85≦B/A≦1. However, if the pattern shape is tapered or reversely tapered, it is determined to be defective even if B/A is within the above range.

<Synthesis of Resin A> Synthesis Example 1 In a flask equipped with a stirrer, a cooling tube and a thermometer, m
-Cresol 67.
6g (0.63mol) 2,3,5-trimethylphenol 10.0g (0.073mol) p-cresol
31.8g (0.29
mole) 37% by weight formaldehyde aqueous solution 107.1
g (formaldehyde: 1.32 mol) and oxalic acid dihydrate 1.33 g
(1.06 x 10-2 mol), immersed the flask in an oil bath, maintained the internal temperature at 100°C, and conducted polycondensation for 30 minutes with stirring.
m-cresol 17
．． 5 g (0.16 mol) and 40.0 g of 2,3,5-trimethylphenol (
0.29 mol) was added thereto, and polycondensation was further carried out for 40 minutes. Next, 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, and water,
Oxalic acid, unreacted raw materials, etc. were removed. The molten resin was then returned to room temperature and collected. This resin is called resin (A1).

Synthesis Example 2 After dissolving the resin (A1) in ethyl cellosolve acetate to a solid content of 20% by weight, twice the weight of methanol and the same amount of water were added to the weight of this resin solution and stirred. I left it there. After being separated into two layers by standing, the resin solution layer (lower layer) was taken out, concentrated, dehydrated, and dried to recover the resin. This resin was mixed with resin (A2
).

Synthesis Example 3 In an autoclave, m-cresol 69
．． 2g (0.64 mol) 2,3,5-trimethylphenol 21.8g (0.16 mol) 37% by weight formaldehyde aqueous solution 61.0g (formaldehyde:
0.75 mol) Oxalic acid dihydrate 6.3g (0.05 mol) water
Charge 52.6g and 182g of dioxane, immerse the autoclave in an oil bath, and bring the internal temperature to 13.
Condensation was carried out for 6 hours while maintaining the temperature at 0° C. and stirring. After the reaction, the temperature was returned to room temperature and the contents were taken out into a beaker. After separating into two layers in this beaker, take out the lower layer,
The resin was recovered by concentration, dehydration, and drying. This resin is called resin (A3).

Synthesis Example 4 In a flask similar to that used in Synthesis Example 1, 13.0 g (0.12 mol) of m-cresol and 32.4 g (0.3 mol) of p-cresol were added.
3,5-xylenol 39.0g (0.32 mol) 37% by weight formaldehyde aqueous solution 56.9g
(Formaldehyde: 0.70 mol) and oxalic acid dihydrate 0.083g (6.59×10
-4 mol), immerse the flask in an oil bath, and lower the internal temperature.
After polycondensation was carried out for 30 minutes by stirring while maintaining the temperature at 100°C, m-cresol was further added.
51.9 g (0.48 mol) and 9.77 g (0.08 mol) of 3,5-dimethylphenol were continuously charged into a flask as the reaction progressed, and polycondensation was performed for 45 minutes. Thereafter, the resin was collected in the same manner as in Synthesis Example 1. This resin is called resin (A4).

Synthesis Example 5 In a flask similar to that used in Synthesis Example 1, 95.2 g (0.
88 mol) 2,3,5-trimethylphenol 24
．． 4g (0.18 mol) 37% by weight formaldehyde aqueous solution 154g (formaldehyde: 1.90 mol) and oxalic acid dihydrate 1.82g (0.014 mol)
The flask was immersed in an oil bath, the internal temperature was maintained at 100°C, and polycondensation was carried out for 90 minutes while stirring, and then 23.8 g (0.22 mol) of m-cresol and 2,3,5 -Trimethylphenol 97
．． 6 g (0.72 mol) was added and polycondensation was further carried out for 60 minutes. Then, the resin was collected in the same manner as in Synthesis Example 1. This resin was dissolved in ethyl cellosolve acetate so that the solid content was 20% by weight, and then 1.8 times the weight of methanol and the same amount of water were added to the weight of this resin solution, stirred, and allowed to stand. After being separated into two layers by standing, the resin solution layer (lower layer) was taken out, concentrated, dehydrated, and dried to recover the resin. This resin is called resin (A5).

<Synthesis of Resin B> Synthesis Example 6 In a flask similar to that used in Synthesis Example 1, 108.0 g (1.00 mol) of 37% by weight m-cresol was added.
Formaldehyde aqueous solution 24.3g (formaldehyde: 0.30 mol) and oxalic acid dihydrate 0.30g (2.40 x 10-3
mol), immerse the flask in an oil bath, and lower the internal temperature to 10
Polycondensation was carried out for 40 minutes while maintaining the temperature at 0°C. Then,
The resin was collected in the same manner as in Synthesis Example 1. This resin is called resin (B1).

<Abbreviation and synthesis of compound (A)> In the following, compound (A), 4,6-bis(4-hydroxy-3,5-dimethylbenzyl)-resorcinol, is converted to compound (A1) (formula ( 5) inside (x1)),
Methyl 2,6-bis(4-hydroxy-3,5-dimethylbenzyl)-3,4,5-trihydroxybenzoate as compound (A2) ((e) in formula (5) above), 4
,5,6-tris(4-hydroxy-3,5-dimethylbenzyl)pyrogallol to compound (A3) (formula (
(c2) in 5) and 4,6-bis(4-hydroxy-3,5-dimethylbenzyl)-2-methylresorcinol to compound (A4) ((g1 in formula (5))
).

<Synthesis of 1,2-quinonediazide compound>
Synthesis Example 7 10.0 g of resin (B1), 13.9 g of 1,2-naphthoquinonediazide-5-sulfonic acid chloride, and 250 g of dioxane were charged and dissolved with stirring. The flask was then immersed in a water bath controlled at 30°C until the internal temperature reached 30°C.
When the temperature became constant, 5.75 g of triethylamine was slowly added dropwise to this solution using a dropping funnel so that the internal temperature did not exceed 35°C. Thereafter, the precipitated triethylamine hydrochloride was removed by filtration, and the filtrate was poured into a large amount of diluted hydrochloric acid to precipitate it.Then, the precipitate was collected by filtration, and dried overnight in a vacuum dryer controlled at 40°C. 2
-Quinonediazide compound (a) was obtained.

Synthesis Example 8 2,3,4-trihydroxybenzophenone 23.
0 g (0.10 mol) 1,2-naphthoquinonediazide-5-sulfonic acid chloride 69.9 g (0.26 mol) and triethylamine 28.9 g (0.286 mol) were used in the same manner as in Synthesis Example 7. A 1,2-quinonediazide compound (b) was obtained.

Synthesis Example 9 2,3,4,4'-tetrahydroxybenzophenone
Synthesis Example 7 except that 24.6 g (0.10 mol) 1,2-naphthoquinonediazide-5-sulfonic acid chloride 107.5 g (0.40 mol) and triethylamine 44.5 g (0.44 mol) were used. In the same manner, 1,2-quinonediazide compound (c) was obtained.

Synthesis Example 10 1,1-bis(4-hydroxyphenyl)-4-[1-
(4-hydroxyphenyl)-1-methylethyl]-1
- Phenylethane 42.4 g (0.10 mol) 1,2-naphthoquinonediazide-5-sulfonic acid chloride 67.2 g (0.25 mol) and triethylamine 27.8 g (0.275 mol) were used. A 1,2-quinonediazide compound (d) was obtained in the same manner as in Example 7.

Examples 1 to 7, Comparative Examples 1 to 2 Resin A, quinonediazide compound, compound (A) and solvent were mixed to form a homogeneous solution, which was then filtered through a membrane filter with a pore size of 0.2 μm. A solution of the composition was prepared. The obtained solution was applied onto 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 a thickness of 1.
．． A resist film of 2 μm was formed and exposed using a wavelength of 365 nm (i-line) through a reticle as described above.
After developing, rinsing, and drying, the resist film was evaluated for sensitivity, resolution, residual film rate, developability, heat resistance, and pattern shape. The results are shown in Table 1 together with the resin used.

[0050]

[Table 1]

Note 1: Each amount added is shown in parts by weight. Note 2: The types of solubility promoters are as follows. α; 1,1,1-tris(4-hydroxyphenyl)
Ethane B1: Resin (B1) obtained in Synthesis Example 6 Note 3: The types of solvent are as follows. S1; Ethyl cellosolve acetate S2; Ethyl lactate S3; Methyl-3-methoxypropionate

005
2]

Effects of the Invention The radiation-sensitive resin composition of the present invention effectively suppresses the generation of scum during resist formation and has excellent developability, as well as high sensitivity, high resolution, heat resistance, and residual film rate. It can be suitably used as a positive resist with excellent properties.

Claims (1)

[Claims] Claim 1: Alkali-soluble resin, the following general formula (1);
[Formula 1] In the formula, X1 to X13 represent a hydrogen atom, an alkyl group, an alkoxy group, or a hydroxyl group, and X1 to X5, X6 to X8, and X9 to X13
At least one hydroxyl group is included in each combination, Y1 to Y4 represent a hydrogen atom or an alkyl group, R1 is a hydrogen atom, -COOR2 (R2 is a hydrogen atom, an alkyl group,
), or the following general formula (2) (X1
4 to X18 represent a group represented by a hydrogen atom, an alkyl group, an alkoxy group or a hydroxyl group; A radiation-sensitive resin composition characterized by comprising: