JP2985400B2 - Radiation-sensitive resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ultraviolet light,
The present invention relates to a radiation-sensitive resin composition suitable as a resist for producing a highly integrated circuit, which is sensitive to radiation such as radiation, electron beam, molecular beam, γ-ray, synchrotron radiation, and proton beam.

[0002]

2. Description of the Related Art Positive resists are widely used in the manufacture of integrated circuits because they provide a high-resolution resist pattern. There is a demand for a positive resist capable of forming a resist.

[0003]

However, in the case of the conventional positive resist, if the distance between the resist patterns to be formed is 0.8 μm or less, the developing property of a small pattern, a hole or the like with a small exposure amount is reduced. And the pattern shape was insufficient. Also, in wet etching performed at the time of manufacturing an integrated circuit, the adhesion between the positive resist and the substrate is important, but it is hard to say that the conventional positive resist has sufficient adhesion. . Furthermore,
In dry etching performed during the manufacture of integrated circuits, it is necessary that the resist pattern does not change due to heat during the etching. Therefore, a positive resist requires heat resistance, but a conventional positive resist has sufficient heat resistance. It was hard to say that she had sex. Also, when the conventional positive resist is out of focus, the pattern shape is deformed, the developability is deteriorated, the deviation from the design line width, etc. is remarkable,
It did not have sufficient focus tolerance. Therefore, an object of the present invention is to provide high resolution and high sensitivity,
An object of the present invention is to provide a radiation-sensitive resin composition which is excellent in developability, pattern shape, adhesiveness and heat resistance, and is suitable as a positive resist having sufficient focus tolerance.

[0004]

Means for Solving the Problems The radiation-sensitive resin composition of the present invention comprises (A) the following structural formula (1):

Embedded image (Wherein m is a number of 2 or 3) and at least one phenol (hereinafter referred to as “phenol (A)”), m-cresol, or m-cresol and p-cresol (Hereinafter referred to as “cresols (A)”) and an alkali-soluble novolak resin obtained by polycondensation using aldehydes (hereinafter referred to as “resin (A)”), and (B ) The following structural formula (2a) or (2b),

Embedded image (Wherein, R ^{1 to} R ¹⁷ each represent a hydrogen atom,
4 alkyl group, an alkoxy group or an -OD group having 1 to 4 carbon atoms (, D is. Indicating any one of a hydrogen atom and 1, 2-quinone diazide sulfonyl group) indicates, and at least of R ¹ to R ⁹ One and at least one of R ^{10 to} R ¹⁷ represent an —OD group, R ¹⁸ represents a hydrogen atom,
Represents any one of alkyl groups, acetyl groups and benzoyl groups. ) (Hereinafter, referred to as “compound (B)”).

Resin (A) The resin (A) used in the present invention is a novolak resin obtained by polycondensing phenols (A) and cresols (A) with aldehydes. Examples of the phenols (A) include 2,3-xylenol,
2,5-xylenol, 3,4-xylenol, 3,5
-Xylenol, 2,3,5-trimethylphenol,
3,4,5-trimethylphenol and the like can be mentioned, and among these, 2,5-xylenol, 3,5-xylenol and 2,3,5-trimethylphenol are preferable. These phenols (A) are used alone or in combination of two or more.

The amount of these phenols (A) and cresols (A) used in the polycondensation of the resin (A) is as follows in the case of m-cresol / phenols (A).
Usually 40 to 95/60 to 5 (molar ratio), preferably 5
0-90 / 50-10 (molar ratio), and in the case of m-cresol / p-cresol / phenols (A),
Usually 20 to 90/5 to 75/5 to 75 (molar ratio), preferably 40 to 80/10 to 50/10 to 50 (molar ratio)
It is.

Further, a particularly preferred combination of the phenols (A) and the cresols (A) in the polycondensation of the resin (A) and the amount thereof are m-cresol /
3,5-xylenol = 50-85 / 15-50 (molar ratio), m-cresol / 2,3,5-trimethylphenol = 70-90 / 10-30 (molar ratio), m-cresol / p-cresol / 2,5-xylenol = 40 ~
60/10 to 30/10 to 30 (molar ratio), m-cresol / p-cresol / 3,5-xylenol = 40 to
60/15 to 30/20 to 40 (molar ratio) and m-cresol / p-cresol / 2,3,5-trimethylphenol = 50 to 80/10 to 30/10 to 30 (molar ratio).

The aldehydes used in the polycondensation include, for example, formaldehyde, trioxane, paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, phenylacetaldehyde,
α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-
Hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde,
Examples thereof include p-nitrobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde, and furfural. Particularly, formaldehyde can be suitably used. These aldehydes can be used alone or in combination of two or more. The amounts of the aldehydes used are phenols (A) and cresols (A)
Is preferably from 0.7 to 3 mol, more preferably from 0.8 to 1.5 mol, per 1 mol of the total amount of

Phenols (A) and cresols (A)
Examples of the catalyst usually used for polycondensation of aldehydes with aldehydes include acidic catalysts such as hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, and acetic acid. The use amount of these acidic catalysts is usually 1 × 10 ^{-5 to} 5 × 10 ^-1 mol per 1 mol of the total amount of the phenols (A) and the cresols (A). In the polycondensation, water is usually used as a reaction medium. However, when the phenols (A) and cresols (A) used in the polycondensation do not dissolve in the aqueous solution of the aldehyde and become heterogeneous from the beginning of the reaction. Can also use a hydrophilic solvent as a reaction medium. Examples of these hydrophilic solvents include alcohols such as methanol, ethanol, propanol and butanol, and cyclic ethers such as tetrahydrofuran and dioxane. The amount of these reaction media used is usually 10
20 to 1000 parts by weight per 0 parts by weight.

[0010] The temperature of the polycondensation can be appropriately adjusted according to the reactivity of the reaction raw materials.
It is. Examples of the polycondensation method include phenols (A),
A method in which cresols (A), aldehydes, acidic catalysts, etc. are charged together and a method in which phenols (A), cresols (A), aldehydes, etc. are added in the presence of an acidic catalyst as the reaction proceeds. Can be adopted.
After the polycondensation, unreacted raw materials, acidic catalyst,
In order to remove the reaction medium and the like, generally, the temperature of the reaction system is raised to 130 to 230 ° C.
Volatile components are distilled off at about 50 mmHg, and the obtained resin (A)
Collect.

The resin (A) used in the present invention comprises:
The weight average molecular weight in terms of polystyrene (hereinafter, referred to as “Mw”) is usually 4,000 to 20,000, particularly 5,000.
It is desirably in the range of １５15,000. Mw is 20
If it exceeds 000, it becomes difficult to uniformly apply the composition of the present invention to a wafer, and further developability and sensitivity are reduced,
When Mw is less than 4000, heat resistance tends to decrease. In order to obtain a resin (A) having a high Mw, for example, the resin (A) recovered after completion of the polycondensation is treated with ethyl cellosolve acetate, dioxane, methanol,
After dissolving in a good solvent such as ethyl acetate, a poor solvent such as water, n-hexane, or n-heptane is mixed, and then a resin solution layer to be separated is separated to recover a high molecular weight resin (A). . In the composition of the present invention, the above-mentioned resin (A) may be used alone,
You may mix | blend in the combination of kinds or more.

Compound (B) The compound (B) used in the present invention is a compound represented by the aforementioned structural formula (2a) or (2b). In these structural formulas, R ^{1 to} R ¹⁷ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or an —OD group (where D is a hydrogen atom or 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 Represents any one of 1,2-quinonediazide groups such as -4-sulfonyl group), and at least one of R ^{1 to} R ⁹ and at least one of R ^{10 to} R ¹⁷ are —O
Shows the D group, R ¹⁸ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, one of the acetyl group or a benzoyl group.

Here, examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, iso-
Examples thereof include a propyl group, an n-butyl group, a sec-butyl group, an iso-butyl group and a t-butyl group. Also,
Examples of the alkoxy group having 1 to 4 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a sec-butoxy group, an iso-butoxy group and a t-butoxy group. Can be mentioned.

In the structural formula (2a), examples of the compound in which D is a hydrogen atom include 2-phenyl-4 ', 7-
Dihydroxy-4-flavanone, 2-phenyl-4 ',
7-dihydroxy-8-methyl-4-flavanone, 2-
Phenyl-2 ', 4', 7-trihydroxy-4-flavanone, 2-phenyl-2 ', 5,7-trihydroxy-4-flavanone, 2-phenyl-2', 7,8-trihydroxy-4 -Flavanone, 2-phenyl-3 ',
4 ', 7-trihydroxy-4-flavanone, 2-phenyl-3', 6,8-trihydroxy-4-flavanone, 2-phenyl-3 ', 7,8-trihydroxy-4
-Flavanone, 2-phenyl-4 ', 5,7-trihydroxy-4-flavanone, 2-phenyl-4', 7,8
-Trihydroxy-4-flavanone, 2-phenyl-
4 ', 5,7-trihydroxy-3'-methoxy-4-
Flavanone, 2-phenyl-4 ', 7,8-trihydroxy-3'-methoxy-4-flavanone, 2-phenyl-4', 7,8-trihydroxy-5-methyl-4-flavanone, 2-phenyl -2 ', 4', 5,7-tetrahydroxy-4-flavanone, 2-phenyl-2 ',
4 ', 7,8-tetrahydroxy-4-flavanone, 2
-Phenyl-3 ', 4', 6,8-tetrahydroxy-
4-flavanone, 2-phenyl-3 ', 4', 7, 8-
Tetrahydroxy-4-flavanone and the like.

Such a compound can be synthesized, for example, by condensing a substituted or unsubstituted phenol with a substituted or unsubstituted cinnamic acid in the presence of an acidic catalyst. There is also.

In the structural formula (2b), examples of the compound in which D is a hydrogen atom include hematoxylin, 3, 9
-Dimethoxy-7,11b-dihydrobenz [b] indeno [1,2-d] pyran-4,6a, 10 (6H) -triol, 6a-methoxy-7,11b-dihydrobenz [b] indeno [1, 2-d] pyran-3,4,9,10
(6H) -tetraol, 6a-benzoyloxy-
7,11b-dihydrobenz [b] indeno [1,2-
d] pyran-3,4,9,10 (6H) -tetraol,
6a-acetyloxy-7,11b-dihydrobenz [b] indeno [1,2-d] pyran-3,4,9,10
(6H) -tetraol and the like. Although such compounds can be synthesized, they mainly exist as natural products.

Further, as an example of a compound in which D is a 1,2-quinonediazidosulfonyl group in the structural formula (2a) or (2b), D is a hydrogen atom in the structural formula (2a) or (2b) described above. A compound in which some or all of the hydrogen atoms of the hydroxyl groups in a compound (hereinafter, referred to as “compound (H)”) are substituted with a 1,2-quinonediazidosulfonyl group. For example, compound (H) and 1,2-benzoquinonediazide -4-sulfonyl chloride, 1,2
-Naphthoquinonediazide-4-sulfonyl chloride,
It can be obtained by an esterification reaction with 1,2-quinonediazidosulfonyl halide such as 1,2-naphthoquinonediazido-5-sulfonyl chloride or 1,2-naphthoquinonediazide-6-sulfonylchloride.

[0018] Among these, ^2-phenyl-4, 7
-Dihydroxy-4-flavanone, 2-phenyl-
^4, 5, 7-trihydroxy-4-flavanone, 2-
^Phenyl-4, 7,8-trihydroxy-4-flavanone, ^{2-phenyl-3,, 4,,} 7, 8-tetra-hydroxy-4-flavanone, hematoxylin, ^2-phenyl-4, 7-dihydroxy - 4-flavanone 1,2
-Naphthoquinonediazide-5-sulfonic acid ester, 2
- ^phenyl-4, 5, 7-1 trihydroxy-4-flavanone, 2-naphthoquinonediazide-5-sulfonic acid ester, ^2-phenyl-4, 7, 8-trihydroxy-4-flavanone 1, 2-naphthoquinonediazide-5-sulfonic acid ester, ^{2-phenyl-3,
4,} 7, 8-tetra-hydroxy-4-1,2-naphthoquinonediazide-5-sulfonic acid ester and one hematoxylin flavanones, 2-naphthoquinonediazide-5-sulfonic acid ester is preferably used.

These compounds (B) can be used alone or
It is used in combination of more than one kind, and its amount is usually 3 to 100 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the resin (A).

In [0020] solubility promoter composition of the present invention, for the purpose of, for example, to promote alkali solubility of the resin (A), the low-compound (H) other than the low molecular weight phenolic compounds and Mw of 200 to 2,000 An alkali-soluble novolak resin having a molecular weight can also be added as a dissolution accelerator. As the low molecular weight phenol compound, a phenol compound having about 2 to 6 benzene rings is suitably used, and is not particularly limited.

Embedded image (Wherein, R represents a hydrogen atom or a methyl group,
a, b, c and d are each an integer of 0 to 3 (however, except when all are 0), and k, l, m and n are each an integer of 0 to 3. ) Can be mentioned.

The low molecular weight alkali-soluble novolak resin is not particularly limited. For example, in addition to the phenols (A) and cresols (A) used in the polycondensation of the resin (A), for example, And phenols, o-cresol, 1-naphthol, and 2-naphthol. The amount of such a dissolution promoter is usually 5 to 100 parts by weight of the resin (A).
The content is preferably 0 parts by weight or less.

1,2-quinonediazide compound In the composition of the present invention, when D in the structural formula (2a) or (2b) in the compound (B) is not a 1,2-quinonediazide sulfonyl group, 1,2-quinonediazide It is necessary to compound a compound, and when D is a 1,2-quinonediazidosulfonyl group, other 1,2-
A quinonediazide compound can be blended. Such 1,2-quinonediazide compounds include, for example,
1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester, 1,2-naphthoquinonediazide-6-sulfonic acid Esters, and the like, and preferred examples thereof 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-tris (4-hydroxyphenyl) ethane,
1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxyphenyl)-
1,2 of 4- [1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane and 2,4,4-trimethyl-2 ', 4', 7-trihydroxy-2-phenylflavan -Naphthoquinonediazide-5-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, and the like.

In the composition of the present invention, the structural formula (2a)
Alternatively, the compounding amount of the compound (B) in which D in (2b) is a 1,2-quinonediazidosulfonyl group and the other 1,2-quinonediazide compound is usually 3 to 100 parts by weight of the resin (A). 100 parts by weight, preferably 5 to 50 parts by weight, but generally the total amount of 1,2-quinonediazidosulfonyl groups in the composition is 5 to 25% by weight, preferably 1 to 25% by weight.
It is adjusted to be 0 to 20% by weight.

Various Compounding Agents In the composition of the present invention, various compounding agents such as sensitizers and surfactants can be compounded. The sensitizer is compounded for improving the sensitivity of the composition. As such a sensitizer, for example, 2H-pyrido- (3,2-
b) -1,4-Oxazin-3 (4H) -ones, 10
H-pyrido- (3,2-b) -1,4-benzothiazines, urazoles, hydantoins, parbituric acids, glycine anhydrides, 1-hydroxybenzotriazoles, alloxanes, maleimides and the like.
The compounding amount of these sensitizers is usually 50 parts by weight or less, preferably 30 parts by weight or less based on 100 parts by weight of the resin (A).

The surfactant is compounded to improve the coating property and the developing property of the composition. Examples of such a surfactant include polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate, and EFTOP EF301. EF303, EF3
52 (trade name, manufactured by Shin-Akita Kasei), Megafax F
171, F172, F173 (trade names, manufactured by Dainippon Ink and Chemicals), Florad FC430, FC431 (trade names,
Sumitomo 3M), Asahigard AG710, Surflon S-382, SC-101, SC-102,
SC-103, SC-104, SC-105, SC-1
06 (trade name, manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), acrylic acid or methacrylic acid (co) polymer polyflow No. 75, No. 95 (trade name, manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like. The amount of these surfactants is
It is usually 2 parts by weight or less per 100 parts by weight of the solid content of the composition.

Further, the composition of the present invention may contain a dye or a pigment for visualizing the latent image in the irradiated area and reducing the influence of halation upon irradiation, and may improve the adhesiveness. For this purpose, an adhesion aid may be added. Further, if necessary, a storage stabilizer, an antifoaming agent and the like can be added.

Preparation of Composition and Pattern Formation The composition of the present invention is prepared by mixing the resin (A) and the compound (B) described above and the various compounding agents described above, for example, so that the solid content concentration is 20 to 40% by weight. Dissolved in a solvent
It is prepared by filtering through a filter having a pore size of about 0.2 μm. Examples of the solvent 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 ether acetate toluene, xylene, methyl ethyl ketone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-hydroxy-3 -Ethyl methylbutanoate, methyl 3-methoxypropionate,
Ethyl 3-methoxypropionate, ethyl acetate, butyl acetate and the like can be used alone or in combination of two or more.

Further, N-methylformamide, N, N
-Dimethylformamide, N-methylformanilide,
N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethylether, dihexylether, acetonylacetone, isophorone, caproic acid, caprylic acid,
High-boiling solvents such as -octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, and phenyl cellosolve acetate can also be added.

The composition of the present invention is applied to, for example, a silicon wafer or a wafer coated with aluminum or the like by spin coating, flow coating, roll coating, or the like to form a radiation-sensitive layer. The pattern is formed by irradiating the radiation-sensitive layer with radiation through the pattern and developing with a developer.

Examples of the developing solution include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, and methyldiethylamine. Dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo (5,4,0) -7
-Undecene, 1,5-diazabicyclo (4,3,0)
The concentration of an alkaline compound such as -5-nonane is usually
An alkaline aqueous solution dissolved to be 1 to 10% by weight is used.

The developer may be used after adding a suitable amount of a water-soluble organic solvent, for example, alcohols such as methanol and ethanol, and a surfactant. When development is carried out using a developer composed of such an alkaline aqueous solution, rinsing is generally continued with water.

When the composition of the present invention is used as a positive resist, the composition is coated on a wafer or the like, prebaked and exposed, and then subjected to 70-140.
The effect of the present invention can be further improved by performing an operation of heating at ° C. and then performing development.

[0033]

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 methods described below.

[0034] Mw: Toyo Soda Co., Ltd. GPC column (G2000H ₆ 2 this, G3000H ₆
One, using G4000H ₆ one), flow rate 1.5 ml / min, eluent tetrahydrofuran, analytical conditions of column temperature 40 ° C., as measured by gel permeation chromatography method using monodisperse polystyrene as the standard.

Sensitivity: The exposure time is changed using an Nikon-NSR-1505i6A reduction projection exposure machine (lens numerical aperture; 0.45), exposure is performed using i-rays having a wavelength of 365 nm, and then tetramethylammonium hydroxide 2 Using a 0.4% by weight aqueous solution as a developing solution, developing at 25 ° C. for 60 seconds, rinsing with water, and drying to form a resist pattern on the wafer, and forming a 0.6 μm line and space pattern (1 LIS) An exposure time for forming a one-to-one width (hereinafter, referred to as an exposure time)
This is referred to as “optimal exposure time”).

Resolution: The dimension of the smallest resist pattern resolved when exposed for the optimal exposure time was measured.

Residual film ratio: 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 to give a unit of%.

Developability: The degree of scum and residual development was observed and examined using a scanning electron microscope.

Heat resistance: The wafer at which the resist pattern was formed 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 when 0.85 ≦ B / A ≦ 1, the pattern shape was determined to be good. However,
When the pattern shape had a tail, it was determined to be defective even if B / A was within the above range.

Adhesion: A resist pattern having a width of 4.0 μm was formed on a silicon wafer having a silicon oxide film of 7000 ° C., and post-baked at 130 ° C. for 2 minutes, and then a 50% by weight aqueous hydrogen fluoride solution / 40% by weight. Using an aqueous solution of ammonium fluoride = 1/6 (volume ratio) as an etching solution, wet etching was performed at 25 ° C. for 6 minutes, and the erosion width: a at the lower part of the resist pattern as shown in FIG. It was measured. A small erosion width means that it has good adhesion.

Focus tolerance: using a scanning electron microscope, in a 0.6 μm line-and-space pattern, the focus tolerance when the resist pattern size to be resolved is within ± 10% of the mask design size. The swing width was used as a focus range and used as an evaluation index. A large focus range means that it has good focus tolerance.

<Synthesis of Resin A> Synthesis Example 1 A flask equipped with a stirrer, a condenser and a thermometer was charged with 67.6 g (0.63 mol) of m-cresol and 31.8 g (0.29 mol) of p-cresol. 107.1 g of a 37% by weight aqueous solution of formaldehyde (formaldehyde: 1.32 mol) and 1.33 g of oxalic acid dihydrate (1.06 × 10
^-2 mol), the flask is immersed in an oil bath, and the internal temperature is set to 10
After performing polycondensation for 30 minutes while stirring at a temperature of 0 ° C., 17.5 g (0.16 mol) of m-cresol 8.0 g (0.073 mol) of p-cresol and 2,3,5- Trimethylphenol 40.0g
(0.29 mol) and polycondensation was carried out for another 40 minutes. Then, the oil bath temperature was increased to 180 ° C., and simultaneously the pressure in the flask was reduced to 30 to 50 mmHg, and water, oxalic acid, unreacted formaldehyde, m-cresol, p-
-Cresol and 2,3,5-trimethylphenol were removed. Then, the molten resin (A) was returned to room temperature and collected. This resin (A) is referred to as resin (A1).

Synthesis Example 2 Resin (A1) was dissolved in ethyl cellosolve acetate so as to have a solid content of 20% by weight, and twice the amount of methanol and an equal amount of water with respect to the weight of the resin solution were added and stirred. And left. After being left to separate into two layers, the resin solution layer (lower layer) was taken out, concentrated, dehydrated, and dried to collect the resin (A). This resin (A)
Is referred to as resin (A2).

Synthesis Example 3 69.2 g (0.64 mol) of m-cresol 19.5 g (0.16 mol) of 3,5-xylenol 58.4 g of a 37% by weight aqueous solution of formaldehyde (formaldehyde: 0.72 mol) ) Oxalic acid dihydrate 0.90 g (7.14 × 10 ^-3)
Mol) water (54.4 g) and dioxane (182 g) were charged, and the autoclave was immersed in an oil bath.
Polycondensation was carried out for 10 hours while stirring at a temperature of ℃, and 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, the lower layer was taken out, concentrated, dehydrated, and dried to recover the resin (A).
This resin (A) is referred to as resin (A3).

Synthesis Example 4 69.2 g (0.64 mol) of m-cresol 21.8 g of 2,3,5-trimethylphenol (0.
61.0 g of 37% by weight aqueous formaldehyde solution (formaldehyde: 0.75 mol) 6.30 g (0.05 mol) of oxalic acid dihydrate 52.6 g of water and 182 g of dioxane were charged and polycondensation was carried out for 6 hours. The resin (A) was recovered in the same manner as in Synthesis Example 3. This resin (A) is replaced with resin (A)
4).

Synthesis Example 5 In a flask similar to Synthesis Example 1, 86.6 g (0.80 mol) of m-cresol 21.6 g (0.20 mol) of p-cresol 77.1 g of a 37% by weight aqueous solution of formaldehyde (formaldehyde: 0.95 mol) and 0.30 g of oxalic acid dihydrate (2.40 × 10 ⁻³⁾
Mol), the flask was immersed in an oil bath, and the internal temperature was adjusted to 100.
Resin (A) was recovered in the same manner as in Synthesis Example 1 except that polycondensation was performed for 40 minutes while maintaining the temperature at ° C. This resin (A) is referred to as resin (A5).

Synthesis Example 6 In a flask similar to Synthesis Example 1, m-cresol 64.9 g (0.60 mol) p-cresol 43.3 g (0.40 mol) 37% by weight aqueous formaldehyde solution 20.3 g (formaldehyde: 0.25 mol) and oxalic acid dihydrate 0.30 g (2.40 × 10 ⁻³⁾
Mol), the flask was immersed in an oil bath, and the internal temperature was adjusted to 100.
The resin was recovered in the same manner as in Synthesis Example 1 except that polycondensation was performed for 30 minutes while maintaining the temperature at ° C. Mw is 520, and this resin is called a dissolution accelerator (e).

<Synthesis of Compound (B)> Synthesis Example 7 In a flask equipped with a stirrer, a dropping funnel and a thermometer, 27.7 g of 2-phenyl-4 ', 5,7-trihydroxyflavanone (0 .1 mol) 1,2-Naphthoquinonediazide-5-sulfonic acid chloride (67.2 g, 0.25 mol) and dioxane (300 g) were charged and dissolved with stirring. Next, the flask was immersed in a water bath maintained at 30 ° C., and when the internal temperature became constant at 30 ° C., triethylamine was added to the solution.
8 g (0.275 mol) was slowly added dropwise using a dropping funnel so that the internal temperature did not exceed 35 ° C. Thereafter, the precipitated triethylamine hydrochloride was removed by filtration,
The filtrate was poured into a large amount of dilute hydrochloric acid to cause precipitation, and then the precipitate was collected by filtration and dried overnight with a heating vacuum drier kept at 40 ° C. to obtain a compound (B). Compound (B)
1).

Synthesis Example 8 An equivalent amount of 2-phenyl-4 ', 7,8-trihydroxyflavanone (0.1 mol) was used in place of 2-phenyl-4', 5,7-trihydroxyflavanone. Except that, in the same manner as in Synthesis Example 5, compound (B) was obtained. This compound (B) is referred to as compound (B2).

Synthesis Example 9 In place of 2-phenyl-4 ', 5,7-trihydroxyflavanone, hematoxylin 30.2 g (0.1
Compound (B) was obtained in the same manner as in Synthesis Example 5 except that the compound (B) was used. This compound (B) is referred to as compound (B3).

Examples 1 to 5, Comparative Examples 1, 2 Resin (A), compound (B), solvent and, if necessary, 1,2-quinonediazide compound other than compound (B) were mixed to form a homogeneous solution. Thereafter, 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 is 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 1.2 μm-thick resist film. Wavelength of 365 nm (i
, Exposed, developed, rinsed and dried to form a resist pattern. Table 1 shows the evaluation results together with the used resins and the like.

[0053]

[Table 1]

Note 1: Each addition amount is shown in parts by weight. Note 2: (C1) and (C2) are as follows. C1; 2-phenyl-4 ', 5,7-trihydroxy-
4-flavanone C2; hematoxylin Note 3: Other 1,2-quinonediazide compounds (a) to
(C) is as follows. (A); 1,1-bis (4-hydroxyphenyl) -4
-Condensate of 1 mol of [1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane and 2.5 mol of 1,2-naphthoquinonediazide-5-sulfonic acid chloride. (B); 1 mol of 2,3,4,4'-tetrahydroxybenzophenone and 1,2-naphthoquinonediazide-5
Condensate with 3.0 mol of sulfonic acid chloride. (C): a condensate of 1 mol of 2,3,4-trihydroxybenzophenone and 3.0 mol of 1,2-naphthoquinonediazide-5-sulfonic acid chloride. Note 4: The dissolution accelerator (d) is as follows. (D); 1,1-bis (4-hydroxyphenyl) -1
-Phenylethane Note 5: The types of solvents are as follows. (Α); ethyl cellosolve acetate. (Β); ethyl 2-hydroxypropionate.

[0055]

The radiation-sensitive resin composition of the present invention has high resolution and high sensitivity, is excellent in developability, pattern shape, adhesiveness and heat resistance, and is suitable as a positive resist having sufficient focus tolerance. Can be used for

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining a method for evaluating adhesiveness.

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Takao Miura 2--11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd. (56) References JP-A-2-287545 (JP, A) JP-A Heisei 2-84650 (JP, A) JP-A-3-215863 (JP, A) JP-A-62-24241 (JP, A) JP-A-61-97278 (JP, A) (58) Fields investigated (Int. Cl. ^6, DB name) G03F 7/022 G03F 7/023

Claims (1)

(57) [Claims] (A) The following structural formula (1): (Wherein m is a number of 2 or 3), at least one of phenols represented by m-cresol or m
-An alkali-soluble novolak resin obtained by polycondensing -cresol and p-cresol with an aldehyde, and (B) the following structural formula (2a) or (2b): (Wherein, R ^{1 to} R ¹⁷ each represent a hydrogen atom,
4 alkyl group, an alkoxy group or an -OD group having 1 to 4 carbon atoms (, D is. Indicating any one of a hydrogen atom and 1, 2-quinone diazide sulfonyl group) indicates, and at least of R ¹ to R ⁹ One and at least one of R ^{10 to} R ¹⁷ represent an —OD group, R ¹⁸ represents a hydrogen atom,
Represents any one of alkyl groups, acetyl groups and benzoyl groups. A radiation-sensitive resin composition comprising: a compound represented by the formula: