JPH06282072A - Negative radiation-sensitive resin composition - Google Patents

Abstract

PURPOSE:To obtain a negative resist excellent in sensitivity, resolution and developability and good in pattern shape, adhesion, etc., by incorporating an alkali-soluble resin having an alkali solubilizing functional group and an acid generating agent. CONSTITUTION:This negative radiation-sensitive resin composition is an alkali- soluble resin having an acid dissociating functional group (alkali solubilizing functional group) and contg. a resin (alkali-soluble resin) made insoluble or sparingly soluble in alkali by the decomposition of the alkali solubilizing functional group by the action of acid and a compd. generating acid when irradiated with radiation. The composition is applied on a substrate, heated before the irradiation with radiation (exposure) and exposed, hence an acid is generated from the acid generating agent, and the acid dissociating functional group in the alkali-soluble resin is decomposed by the acid. Consequently, the entire composition in the exposed region is made insoluble in alkali, only the composition in the exposed region is left in alkali development, and the negative pattern is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel negative-type radiation-sensitive resin composition suitable as a negative-type resist useful for fine processing using various kinds of radiation.

[0002]

2. Description of the Related Art In the field of microfabrication represented by the manufacture of integrated circuit elements, miniaturization of the processing size in lithography is progressing in order to obtain higher integration, and in recent years, the size of 0.5 μm or less has been achieved. There is a need for a technique capable of performing fine processing with good reproducibility. Conventionally, g-line (wavelength 436) of mercury lamps that are mainly used for microfabrication
(nm) or i-line (wavelength 365 nm), there is a problem that a theoretically sufficient depth of focus cannot be obtained in processing a fine pattern having a line width of 0.35 μm or less. This is a serious problem for the formation of wiring patterns of integrated circuit elements, which are becoming more and more multi-layered and finer with the improvement of the degree.
Therefore, in order to form a finer wiring pattern, far ultraviolet rays such as excimer lasers, which can obtain a wider depth of focus, charged particle beams such as electron beams, or X-rays such as synchrotron radiation, which have shorter wavelengths, are used. The existing lithography is being considered. And, particularly for the negative-type radiation-sensitive resin composition using an alkaline developer,
(A) A composition containing three components of an alkali-soluble resin containing a phenolic hydroxyl group, a compound that generates an acid by irradiation with radiation, and a crosslinking agent that performs a crosslinking reaction of the alkali-soluble resin in the presence of an acid (hereinafter , "Crosslinked resist"), and (b) a composition having a functional group that undergoes a rearrangement reaction by irradiation with radiation (hereinafter referred to as "
It is called "dislocation type resist". Is widely studied (see, for example, JP-A-62-164045 and JP-A-4-165359). However, in the conventional negative radiation-sensitive resin composition,
There are various problems in lithography technology. That is, in the above-mentioned cross-linking type resist, a thermal cross-linking reaction may proceed during baking of the resist in the lithography step. In fact, in many cross-linking type resists, a region which should be originally dissolved in an alkali developing solution, that is, radiation irradiation There is a problem that the thermal cross-linking reaction proceeds even in the region, and as a result, a portion insoluble in the alkali developing solution, that is, so-called undeveloped residue occurs in the unirradiated region. On the other hand, in the dislocation type resists reported so far, the difference in solubility in the alkaline developer before and after the rearrangement reaction is small, a sufficient contrast cannot be obtained between the radiation-irradiated region and the unirradiated region, and There is a problem that productivity is low because efficiency is low and a large amount of radiation needs to be irradiated.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a negative radiation-sensitive resin composition which is useful as a negative resist having high sensitivity and high resolution, excellent developability, and good pattern shape and adhesiveness. The purpose is to provide.

[0004]

According to the present invention, the above-mentioned problem is solved by an alkali-soluble resin having an acid-dissociable functional group (hereinafter, referred to as "alkali-solubilizing functional group") which exhibits an action of improving alkali solubility. In addition, the alkali-insoluble or alkali-insoluble resin (hereinafter, referred to as “alkali-soluble resin”) by which the alkali-solubilizing functional group is decomposed by the action of an acid, and irradiation with radiation (hereinafter, referred to as “exposure”) And a negative-type radiation-sensitive resin composition containing a compound that generates an acid (hereinafter, referred to as “acid generator”).

The present invention will be described in detail below, which will clarify the purpose, constitution and effect of the present invention. First, the mechanism for forming a negative pattern and the advantages thereof in the negative radiation-sensitive resin composition of the present invention will be described. The negative radiation-sensitive resin composition of the present invention is applied to a substrate such as a silicon wafer and heat-treated (hereinafter referred to as "pre-exposure baking") before exposure for use. When the composition film after baking before exposure is exposed to light, an acid is generated from the acid generator, and the generated acid causes a decomposition reaction of the acid dissociable functional group in the alkali-soluble resin. In this case, a heat treatment (hereinafter referred to as “post-exposure baking”) may be performed after the exposure, if necessary. Thus, the composition of the exposed area is
When the alkali-solubilizing functional group of the alkali-soluble resin in the composition is decomposed, the entire composition becomes insoluble or sparingly soluble in alkali. On the other hand, the composition of the unexposed area has alkali solubility because the alkali-soluble resin in the composition retains the alkali-solubilizing functional group and is soluble in the alkali developing solution, so that By developing with, only the composition in the exposed region remains and a negative pattern is formed.

In the negative-type radiation-sensitive resin composition of the present invention, the acid generated from the acid generator acts catalytically, so that the exposure amount required is small and the sensitivity is high. . Moreover, since no cross-linking agent is used, there is also an advantage that there is no problem of development residual in the unexposed area due to the thermal cross-linking reaction by the cross-linking agent.

The components used in the negative-type radiation-sensitive resin composition of the present invention will be sequentially described below. The alkali-soluble resin is a resin which is alkali-soluble by introducing an alkali-solubilizing functional group, which will be described later, into a resin which is insoluble or hardly soluble in an alkali developing solution (hereinafter, simply referred to as “alkali-insoluble resin”). It is a resin that becomes alkali-insoluble or alkali-insoluble by the action of decomposing the alkali-solubilizing functional group.

The chemical structure and composition of the alkali-insoluble resin are appropriately selected depending on the type and concentration of the alkali developer used. That is, as the alkali-insoluble resin, depending on the development conditions actually adopted, after baking the resin composition film applied on the substrate before exposure, when exposed and developed, the film thickness of the exposed region, A resin that remains 50% or more, preferably 90% or more of the film thickness before development is selectively used.

As such an alkali-insoluble resin,
For example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o-
Hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 3-chloro-4-hydroxystyrene, 4-chloro-3-hydroxystyrene, 3-bromo-4-hydroxystyrene, 4-bromo-3-hydroxystyrene, 3 -Methyl-4-hydroxystyrene, 4
-Methyl-3-hydroxystyrene, 3-ethyl-4-
Hydroxystyrene, 4-ethyl-3-hydroxystyrene, 3-propyl-4-hydroxystyrene, 4-propyl-3-hydroxystyrene, 3-t-butyl-4
-Hydroxystyrene, 4-t-butyl-3-hydroxystyrene, 3-phenyl-4-hydroxystyrene,
4-phenyl-3-hydroxystyrene, 3-naphthyl-4-hydroxystyrene, 4-naphthyl-3-hydroxystyrene, 3-benzyl-4-hydroxystyrene, 4-benzyl-3-hydroxystyrene, 3-styryl-4 -Hydroxystyrene, 4-styryl-3-hydroxystyrene, 3-vinyl-4-hydroxystyrene, 4-vinyl-3-hydroxystyrene, 3-propenyl-4-hydroxystyrene, 4-propenyl-3-
Hydroxystyrene, 3-cumyl-4-hydroxystyrene, 4-cumyl-3-hydroxystyrene, 2-methyl-4-hydroxystyrene, 2,6-dimethyl-4-
Hydroxystyrene, o-hydroxy-α-methylstyrene, m-hydroxy-α-methylstyrene, p-hydroxy-α-methylstyrene, pt-butoxystyrene, pt-butoxy-α-methylstyrene, o- Acetoxystyrene, m-acetoxystyrene, p-acetoxystyrene, o-acetoxy-α-methylstyrene,
m-acetoxy-α-methylstyrene, p-acetoxy-α-methylstyrene, (meth) acrylonitrile, crotonnitrile, malein nitrile, fumaronitrile,
Mesacon nitrile, citracon nitrile, itacone nitrile, (meth) acrylamide, crotonamide, maleamide, fumaramide, mesaconamide, citracone amide, itaconic amide, maleimide, n-phenylmaleimide, (meth) acrylic acid, crotonic acid, maleic acid, anhydrous Maleic acid, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, mesaconic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylic Isopropyl acid, n-butyl (meth) acrylate,
T-butyl (meth) acrylate, n (meth) acrylate
-Hexyl, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, vinyl alcohol, methacrylic alcohol, (meth) allyl alcohol, vinylaniline, vinylpyridine , Vinyl-ε
-Homopolymers or copolymers of monomers such as caprolactam, vinylpyrrolidone, vinylimidazole and the like are appropriately used, which satisfy the above-mentioned requirements.

For example, when a 2 wt% tetramethylammonium hydroxide aqueous solution is used as a developing solution and the development is carried out at 25 ° C. for 60 seconds, the alkali-insoluble resin is
For example, a copolymer having a molar ratio of styrene to a hydroxystyrene monomer of 1/9 to 7/3, preferably 3/7 to 6/4, a molar ratio of methyl methacrylate to a hydroxystyrene monomer. Is 2/8 to 8/2, preferably 4/6 to 7
A / 3 copolymer or the like is preferable.

The alkali-insoluble resin is obtained by directly polymerizing the corresponding monomer or monomer mixture by radical polymerization, anion polymerization, thermal polymerization, or the like, or t-butyl of the phenolic hydroxyl group of the hydroxystyrene monomer. It can be produced by a method of protecting with a group, an acetyl group, a t-butoxycarbonyl group, a trialkylsilyl group and the like, polymerizing or copolymerizing, and then hydrolyzing to remove these protecting groups.

When the alkali-insoluble resin has an aromatic skeleton, the aromatic skeleton can be partially hydrogenated before use. The hydrogenation rate in this case is usually 70
% Or less, preferably 50% or less, more preferably 40%
% Or less.

As the alkali-insoluble resin, novolac resins can be used as long as they have low solubility in an alkali developing solution and satisfy the above-mentioned requirements.
Such a novolac resin has an action of lowering the solubility of the novolac resin in an alkali developing solution. For example, substituted phenols such as 3,5-xylenol and 2,3,5-trimethylphenol are contained in the starting phenol compound. It can be obtained by adding the above to and polycondensing.

The amount of the substituted phenols added varies depending on the type of the substituted phenols used, but is usually within the range of 5 to 70 mol% of the starting phenol compound. If the amount of the substituted phenols added is less than 5 mol%, the degree of decrease in solubility in the alkali developing solution will be insufficient, and if it exceeds 70 mol%, the performance such as sensitivity as a resist may deteriorate.

Such a novolac resin can be produced, for example, by polycondensing a phenol compound containing at least one of the above-mentioned substituted phenols and a carbonyl compound in the presence of an acidic catalyst.

Examples of the phenol compound include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-propylphenol,
m-propylphenol, p-propylphenol, o
-Butylphenol, m-butylphenol, p-butylphenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol,
2,3,5-Trimethylphenol, 3,4,5-Trimethylphenol, p-phenylphenol, hydroquinone, catechol, resorcinol, 2-methylhydroquinone, 2-methylresorcinol, phloroglucinol, pyrogallol, bisphenol-A, bisphenol -E, bisphenol-F, bisphenol-S
Etc. are used alone or in combination of two or more so that the resulting novolak resin satisfies the above requirements.

The carbonyl compounds are preferably aldehydes such as formaldehyde, acetaldehyde, propylaldehyde, benzaldehyde,
Examples thereof include phenylacetaldehyde, and these aldehydes may be used alone or in combination of two or more, and formaldehyde is particularly preferable.

When formaldehyde is used as the aldehydes, examples of the formaldehyde source include formalin, trioxane, paraformaldehyde, and the like.
Examples thereof include hemiformals such as methyl hemiformal, ethyl hemiformal, propyl hemiformal, butyl hemiformal, and phenyl hemiformal. These formaldehyde sources may be used alone or in combination of two or more, and formalin and butyl hemiformal are particularly preferable.

The amount of these aldehydes used is preferably 0.7 to 3 mol per mol of the phenol compound,
More preferably, it is 0.75-1.3 mol.

Examples of the acid catalyst used in producing the novolac resin include hydrochloric acid, nitric acid, sulfuric acid, formic acid,
Examples thereof include oxalic acid, acetic acid, p-toluenesulfonic acid and the like. The amount of these acidic catalysts used is usually about 1 × 10 ^{−4 to} 5 × 10 ⁻¹ mol per mol of the phenol compound.

In the polycondensation for producing the novolac resin, water is usually used as the reaction medium, but when the phenol compound used is not dissolved in the aqueous solution of the carbonyl compound and becomes a heterogeneous system from the initial stage of the reaction. It is also possible to use hydrophilic organic solvents as reaction medium. Examples of such a hydrophilic organic solvent include alcohols such as methanol, ethanol, propanol and butanol,
Acyclic ethers such as diethylene glycol dimethyl ether, 1,2-dimethoxyethane, and 1,2-diethoxyethane, cyclic ethers such as tetrahydrofuran and dioxane, and the like can be given. The amount of these reaction media used is usually 20 per 100 parts by weight of the reaction raw material.
~ 1000 parts by weight.

The polystyrene-reduced weight average molecular weight (hereinafter referred to as "Mw") of the alkali-insoluble resin by gel permeation chromatography is preferably 1,5.
00-300,000, more preferably 3,000-
It is 100,000. If the Mw is less than 1,500, the heat resistance of the resist tends to decrease,
If it exceeds 50,000, the resolution as a resist tends to decrease.

In the present invention, the alkali-insoluble resin may be used alone or in combination of two or more kinds.

Next, the alkali-solubilizing functional group introduced into the alkali-insoluble resin is a substituent having at least one acidic group. Examples of such an acidic group include a phenolic hydroxyl group, a carboxyl group, a sulfonic acid group, and the like, and a carboxyl group is particularly preferable.

Examples of the alkali-solubilizing functional group having a carboxyl group include groups represented by the following formula (1).

[Chemical 1] [In Formula (1), R ¹ and R ² may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and 6 to 6 carbon atoms.
A group selected from an aryl group having 10 and an aralkyl group having 7 to 9 carbon atoms is shown, and n is an integer of 1 to 4. ]

The alkali-solubilizing functional group introduced into the alkali-insoluble resin varies depending on the chemical structure and composition of the alkali-insoluble resin, development conditions and the like. For example, as the alkali-insoluble resin, styrene and a hydroxystyrene monomer are used. Molar ratio is 1/9 to 7/3, preferably 3/7 to 6/4
Copolymer, the molar ratio of methyl methacrylate and hydroxystyrene-based monomer is 2/8 to 8/2, preferably 4 /
6 to 7/3 copolymer, or m-cresol and 3,
Preferable alkali when developing at 25 ° C. for 60 seconds using a cocondensation resin having a molar ratio of 5-xylenol of 3/7 to 7/3 and using a 2 wt% tetramethylammonium hydroxide aqueous solution as a developing solution. Examples of the solubilizing functional group include groups represented by the following formulas (2) to (10).

[0027] _{-C (CH 3) 2 COOH ···} (2) -CH (CH 3) COOH ··· (3) -CH 2 COOH ··· (4) -CF 2 COOH ··· (5) −CCl ₂ COOH ・ ・ ・ (6) −CH (OCH ₃ ) COOH ・ ・ ・ (7) −C (OCH ₃ ) ₂ COOH ・ ・ ・ (8) −CH (C ₆ H ₅ ) COOH ・ ・ ・ ( _{9) -C (C 6 H 5} ) 2 COOH ··· (10)

The introduction ratio of the alkali-solubilizing functional group to the alkali-insoluble resin cannot be unconditionally defined depending on the chemical structure of the functional group, but is preferably 5 to 120 parts by weight with respect to 100 parts by weight of the alkali-insoluble resin. When the introduction ratio of the alkali solubilizing functional group is less than 5 parts by weight, the difference in solubility between the exposed portion and the unexposed portion in the alkali developing solution is small,
The resolution as a resist tends to decrease, and
If it exceeds 20 parts by weight, the volume change of the composition film when the alkali-solubilizing functional group is decomposed becomes large, and the cross-sectional shape of the resist pattern may be distorted.

As a method for introducing the alkali-solubilizing functional group into the alkali-insoluble resin, various methods can be adopted depending on the chemical structure of the functional group. For example, for an alkali-insoluble resin having a phenolic hydroxyl group, a carboxylic acid ester skeleton is introduced using a halogenated carboxylic acid ester and a basic catalyst, as schematically shown by the following formula, and then the carboxylic acid is introduced. A method of selectively hydrolyzing the ester skeleton portion to convert it into a carboxyl group is preferable.

[0030]

[Chemical 2] (Here, X represents a halogen atom, R ^{3 to} R ⁷ may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms,
It shows a group selected from an aryl group having 6 to 10 carbon atoms and an aralkyl group having 7 to 9 carbon atoms, and m is an integer of 1 to 4. )

Specific examples of the halogenated carboxylic acid ester include methyl α-bromoacetate, ethyl α-bromoacetate, α-bromoacetate isopropyl, α-bromoacetate t.
-Butyl, methyl α-chloroacetate, ethyl α-chloroacetate, isopropyl α-chloroacetate, α-chloroacetate t-
Butyl, methyl α-bromopropionate, ethyl α-bromopropionate, isopropyl α-bromopropionate, t-butyl α-bromopropionate, methyl α-chloropropionate, ethyl α-chloropropionate, α
-Isopropyl chloropropionate, t-butyl α-chloropropionate, methyl 2-bromopropionate, 2
-Ethyl bromopropionate, isopropyl 2-bromopropionate, t-butyl 2-bromopropionate, 2
-Methyl chloropropionate, ethyl 2-chloropropionate, isopropyl 2-chloropropionate, t-butyl 2-chloropropionate, methyl α-bromoisobutyrate, ethyl α-bromoisobutyrate, isopropyl α-bromoisobutyrate, α-bromoiso Examples thereof include t-butyl butyrate, methyl α-chloroisobutyrate, ethyl α-chloroisobutyrate, isopropyl α-chloroisobutyrate, and t-butyl α-chloroisobutyrate.

The basic catalyst used together with the halogenated carboxylic acid ester should be one that can introduce the carboxylic acid ester skeleton into the alkali-insoluble resin without hydrolyzing the carboxylic acid ester skeleton portion. For example, an organic base or an inorganic base may be used. Examples of such a basic catalyst include ammonia, methylamine, ethylamine, n-propylamine, dimethylamine, diethylamine, morpholine, triethylamine,
Pyridine, 1,8-diazabicyclo [5.4.0] -7
-Undecene, sodium carbonate, potassium carbonate, potassium iodide and the like can be mentioned. The amount of these basic catalysts used is preferably 1 equivalent or more, more preferably more than 1 equivalent and 3 equivalents or less with respect to 1 mol of the halogenated carboxylic acid ester. When the amount of the basic catalyst used is less than 1 equivalent, it becomes difficult to introduce a predetermined amount of carboxylic acid ester skeleton into the alkali-insoluble resin.

The alkali-soluble resin is prepared, for example, by introducing a carboxylic acid ester skeleton into the alkali-insoluble resin as described above, and then hydrating it with sodium hydroxide or potassium hydroxide in a solvent such as t-butyl alcohol. It can be obtained by selectively hydrolyzing the carboxylic acid ester skeleton portion with an alkali as a catalyst to convert it into a carboxyl group.

In the present invention, the alkali-soluble resins may be used alone or in admixture of two or more.

Next, examples of the acid generator include, for example, Japanese Patent Laid-Open No.
0-15993, JP-A-60-37549, JP-A-60-52845, and JP-A-63-29.
2128, JP-A-1-293339, and the like, onium salts, halogen-containing compounds, diazoketone compounds, sulfone compounds, sulfonic acid compounds and the like can be mentioned. Can be mentioned.

Onium salts: iodonium salts, sulfonium salts, phosphonium salts, diazonium salts, ammonium salts, pyridinium salts and the like. Preferred onium salts are diphenyliodonium trifluoromethanesulfonic acid, diphenyliodonium pyrene sulfonate, diphenyliodonium dodecylbenzene sulfonate, diphenyliodonium hexafluoroantimonate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium naphthalene sulfonate, triphenylsulfonium trifluoromethanesulfone. acid,
(Hydroxyphenyl) benzylmethyl sulfonium toluene sulfonate and the like.

Halogen-containing compounds: haloalkyl group-containing hydrocarbon compounds, haloalkyl group-containing heterocyclic compounds and the like. Preferred halogen-containing compounds are 1,1-bis (4
-Chlorophenyl) -2,2,2-trichloroethane,
Phenyl-bis (trichloromethyl) -s-triazine, naphthyl-bis (trichloromethyl) -s-triazine and the like.

Diazoketone compound: 1,3-diketo-2
-Diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds and the like. Preferred diazoketone compounds are
1,2-naphthoquinonediazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-4-sulfonic acid ester of 2,3,4,4'-tetrahydrobenzophenone, 1,1,1-tris (4-hydroxyphenyl) 1,2-naphthoquinonediazide-4-sulfonic acid ester of ethane and the like.

Sulfone compound: β-ketosulfone, β-
Sulfonyl sulfone and the like. The preferred sulfone compound is 4
-Trisphenacyl sulfone, mesityl phenacyl sulfone, bis (phenylsulfonyl) methane and the like.

Sulfonic acid compounds: alkyl sulfonates, haloalkyl sulfonates, aryl sulfonates, imino sulfonates and the like. Preferred sulfonic acid compounds are benzoin tosylate, tris triflate of pyrogallol, nitrobenzyl-9,10-.
Examples thereof include diethoxyanthracene-2-sulfonate.

These acid generators may be used alone or in admixture of two or more, and the compounding amount thereof is usually 0.1 to 2 per 100 parts by weight of the alkali-soluble resin.
0 parts by weight, particularly preferably 0.5 to 10 parts by weight.
The content of the acid generator is 0.1 to 20 parts by weight, particularly 0.5 to
When the amount is within the range of 10 parts by weight, generation of acid and subsequent decomposition reaction of the alkali-solubilizing functional group proceed smoothly, side reactions hardly occur, and an excellent resist pattern can be formed.

In the negative-type radiation-sensitive resin composition of the present invention, when an i-ray of a mercury lamp or radiation having a wavelength longer than that is used as an exposure light source, the acid generator is one of suitable sensitizers. It can also be used in combination with the above. Examples of such sensitizers include phenothiazines, anthracenemethanols, aromatic nitro compounds, and thioxanthone compounds. These sensitizers can be used alone or in admixture of two or more, and the amount of the sensitizer to be added is 10% by weight of the alkali-soluble resin in the composition.
Usually, 50 parts by weight or less, preferably 30 parts by weight
It is less than or equal to parts by weight.

If desired, the negative-type radiation-sensitive resin composition of the present invention may contain various other additives such as a surfactant and an acid diffusion controller.

The above-mentioned surfactant exhibits an action of improving the coating property, striation, developability and the like of the composition. Examples of such a surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate. In addition to rates, F-top EF301, EF303, EF352
(Product name, manufactured by Shin-Akita Kasei), Megafax F171
F172, F173 (trade name, manufactured by Dainippon Ink), Florard FC430, FC431 (trade name, manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-38
2, SC-101, SC-102, SC-103, SC
-104, SC-105, SC-106 (trade name, manufactured by Asahi Glass), KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, No. 95 (trade name, manufactured by Kyoeisha Oil and Fat Chemical Co., Ltd.) and the like. These surfactants can be used alone or in admixture of two or more, and the blending amount thereof is 100 parts by weight of the alkali-soluble resin,
Usually, it is 2 parts by weight or less.

Further, the acid diffusion control agent controls the diffusion of the acid generated by exposure, further improves the shape of the resist pattern to be formed, and improves the stability of the coating film of the composition after exposure. Have.

A basic compound is used as the acid diffusion control agent, and a preferred basic compound is a basic nitrogen-containing compound. Examples of the acid diffusion control agent include ammonia, trimethylamine, triethylamine, tripropylamine, tributylamine, aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4- Methylaniline,
2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 1-naphthylamine, 2-naphthylamine,
Diphenylamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, pyrrolidine, piperidine, imidazole, 4-methylimidazole, 4-
Methyl-2-phenylimidazole, thiabendazole, pyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine, 1-methyl-4-
Phenylpyridine, 2- (1-methylpropyl) pyridine, 2- (1-ethylpropyl) pyridine, nicotinamide, dibenzoylthiamine, riboflavin tetraacetate,
4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,
4'-diaminodiphenylamine, 2,2-bis (4-
Aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2- (4
-Aminophenyl) -2- (3-hydroxyphenyl)
Propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,3-bis [1- (4
-Aminophenyl) -1-methylethyl] benzene,
1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene and the like can be mentioned.

The amount of these acid diffusion controlling agents to be compounded is usually 10 parts by weight or less, preferably 5 parts by weight or less, per 100 parts by weight of the alkali-soluble resin.

The negative-working radiation-sensitive resin composition of the present invention contains a dye or a pigment to visualize a latent image in an exposed area and reduce the effect of halation during exposure, and an adhesion promoter. By blending, it is possible to improve the adhesiveness to the substrate. Furthermore, a storage stabilizer, a defoaming agent, etc. can be added as other additives.

The negative-type radiation-sensitive resin composition of the present invention comprises
Upon its use, it is dissolved in a solvent so that the solid content concentration becomes, for example, 20 to 40% by weight, and then, for example, 0.2
A composition solution is prepared by filtering with a filter of about μm.

Examples of the solvent used for preparing the composition solution 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. , Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclohexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2- Hydroxy Ethyl acid, 2-hydroxy-2-methylpropionic acid ethyl, ethoxyethyl acetate, hydroxyethyl acetate, 2-hydroxy-3-methyl-butyric acid methyl, methyl 3-methoxypropionate, 3
Ethyl methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl acetoacetate, ethyl acetoacetate and the like can be mentioned. These solvents are used alone or in admixture of two or more.

If necessary, the solvent may contain N-.
Methylformamide, N, N-dimethylformamide,
N-methylformanilide, N-methylacetamide,
N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether,
Dihexyl ether, acetonylacetone, 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,
It is also possible to add one or more high boiling point solvents such as phenyl cellosolve acetate.

When forming a resist pattern from the negative-type radiation-sensitive resin composition of the present invention, the composition solution prepared as described above is applied by means such as spin coating, cast coating, or roll coating. After forming a resist film by coating on a substrate such as a silicon wafer or a wafer covered with aluminum, pre-exposure baking is performed. The temperature of this pre-exposure baking is usually 70 to 140 ° C,
It is preferably 90 to 120 ° C. Then, the resist film is exposed through a predetermined mask pattern. Examples of radiation that can be used at that time include ultraviolet rays such as g-line (wavelength 436 nm) and i-line (wavelength 365 nm) of a mercury lamp, bright line spectrum (wavelength 254 nm) of a mercury lamp,
Far ultraviolet rays such as excimer laser (wavelength 248 nm), X-rays such as synchrotron radiation, charged particle beams such as electron beams and the like can be appropriately selected and used. The exposure conditions such as the radiation dose are appropriately selected according to the composition of the composition, the type of each additive, and the like.

In the present invention, it is preferable to perform post-exposure baking after exposure. The heating conditions vary depending on the composition of the composition, the type of each additive, etc., but usually 70 to 1
The temperature is 40 ° C, preferably 90 to 130 ° C. By such post-exposure baking, the reaction due to the generated acid can be efficiently advanced, the apparent sensitivity of the resist film can be further improved, and the effect of the present invention can be further improved.

After that, a predetermined resist pattern is formed by developing with an alkali developing solution. Examples of the alkaline developer 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, 1,8
-Diazabicyclo- [5.4.0] -7-undecene,
An alkaline aqueous solution prepared by dissolving an alkaline compound such as 1,5-diazabicyclo- [4.3.0] -5-nonane in an amount of usually 1 to 10% by weight, preferably 2 to 5% by weight is used. .

The developer contains a water-soluble organic solvent,
For example, alcohols such as methanol and ethanol and a surfactant can be added in appropriate amounts. When using a developing solution consisting of an alkaline aqueous solution as described above,
Generally, it is washed with water after development.

[0056]

EXAMPLES The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to these examples unless it exceeds the gist. Here, the measurement of Mw and the evaluation of the resist were performed by the following methods. Mw Tosoh Corp. GPC column (G2000H _XL : 2 pieces,
G3000H _XL : 1 bottle, G4000H _XL : 1 bottle), a flow rate of 1.0 ml / min, an elution solvent of tetrahydrofuran, and a column temperature of 40 ° C under the analysis conditions, and a gel permeation chromatography method using monodisperse polystyrene as a standard. It was measured by.

Resolution Each composition solution was spin-coated on a silicon wafer, and then pre-exposure baking was performed on the resist film to change the exposure time through a mask pattern and irradiate with KrF excimer laser manufactured by Admon Science Co. Device "MBK-400
1. A KrF excimer laser having a wavelength of 248 nm is exposed using "TL-N", and post-exposure baking is performed, and then 2.
Using a 38 wt% tetramethylammonium hydroxide aqueous solution as a developing solution, development was performed at 25 ° C. for 60 seconds, followed by washing with water and drying to form a resist pattern. At this time, the exposure time for forming a 0.5 μm line-and-space pattern (1L1S) with a line width of 1: 1 is taken as the optimum exposure time, and the minimum resist resolved when exposed at the optimum exposure time. The dimensions of the pattern were measured and used as the resolution.

Using a pattern scanning electron microscope, the length A of the lower side and the length B of the upper side of the square section after development of a resist pattern of 0.6 μm are developed.
Was measured, and when 0.85 ≦ B / A ≦ 1, the pattern shape was determined to be good. However, 0.85 ≦ B / A ≦ 1
Even if the pattern shape is trailing or an overhang shape is observed, the pattern shape is not good.

[0059] The development of a scanning electron microscope to examine the scum and undeveloped the presence and extent after development.

Synthesis Example 1 88 g of 4-t-butoxystyrene and 52 g of styrene
Was dissolved in 176 g of dioxane, a nitrogen bubble was carried out for 30 minutes, 8.2 g of 2,2′-azobisisobutyronitrile was added as a polymerization initiator, and polymerization was carried out at 70 ° C. for 6 hours. Then, the reaction solution was dropped into a large amount of methanol to precipitate a polymer, and the precipitated polymer was dried for 24 hours in a vacuum dryer maintained at 60 ° C. The obtained polymer had Mw = 11,000, Mw / Mn (where Mn is a number average molecular weight) = 2.63, and the yield was 95% by weight. 100 g of this polymer was added to 500 g of dioxane with stirring to dissolve, and 100 g of 1 wt% sulfuric acid was gradually added to this solution under reflux, and the mixture was further refluxed for 2 hours to give t-butoxy group in the polymer. Was hydrolyzed. The reaction solution was dropped into water to precipitate a polymer, the precipitated polymer was separated by filtration, washed with pure water, and then dried overnight in a vacuum dryer maintained at 60 ° C. The obtained p-hydroxystyrene-styrene copolymer had Mw of 8400 and Mw / Mn =
It was 2.59 and was insoluble in a 2.38 wt% tetramethylammonium hydroxide aqueous solution. The yield of the copolymer was 81% by weight, and the molar ratio of p-hydroxystyrene and styrene was 1: 1.06. This copolymer is referred to as an alkali-insoluble resin (a).

Synthesis Example 2 54 g of m-cresol, 74 g of 3,5-xylenol,
A mixture of 60.0 g of butyl hemiformal and 0.0126 g of oxalic acid dihydrate was reacted at 130 ° C. for 2 hours. After that, unreacted raw materials, water, etc. are removed, and Mw = 6
500, Mw / Mn (where Mn is the number average molecular weight) =
It was 3.52, and a novolac-based resin that was sparingly soluble in a 2.38 wt% tetramethylammonium hydroxide aqueous solution was obtained. The yield of the novolak resin was 90% by weight. This resin is referred to as an alkali-insoluble resin (b).

Synthesis Example 3 22.4 g of the alkali-insoluble resin (a) obtained in Synthesis Example 1
(0.2 mol) was dissolved in 200 g of acetone and then 2
16.7 g (0.08 g) of t-butyl-bromopropionate
Mol), 11.3 g of potassium carbonate and 5.4 g of potassium iodide were added, and the mixture was reacted under reflux for 6 hours. Then, the reaction solution was dropped into water to precipitate a polymer, and the precipitated polymer was dried in a vacuum dryer maintained at 40 ° C. for 24 hours. As a result of ¹ H-NMR measurement, the obtained polymer had a hydrogen atom of the phenolic hydroxyl group of -CH (CH ₃ ) COOC (CH
₃ ) It had a structure substituted with ₃ groups. 20 g of this polymer was dissolved in 250 g of t-butyl alcohol together with 8 g of sodium hydroxide and 20 g of water and reacted under reflux for 6 hours. Then, the reaction solution was dropped into 2 liters of water in which 20 g of oxalic acid and a small amount of hydrochloric acid were previously dissolved to precipitate a polymer, and the precipitated polymer was separated by filtration, washed thoroughly with water, and then maintained at 40 ° C. It was dried in a vacuum dryer for 24 hours. As a result of ¹ H-NMR measurement, the obtained polymer had a hydrogen atom of a phenolic hydroxyl group of -CH (CH ₃ ) C.
It had a structure substituted with OOH groups and was easily dissolved in a 2.38 wt% tetramethylammonium hydroxide aqueous solution. This polymer is referred to as an alkali-soluble resin (A).

Synthesis Example 4 22.4 g of the alkali-insoluble resin (a) obtained in Synthesis Example 1
(0.2 mol) and 22.4 g (0.1 mol) of t-butyl α-methoxybromoacetate were dissolved in 200 g of ethyl acetate, and then water in which 14.1 g of potassium carbonate and 6.8 g of potassium iodide were dissolved in advance. 100 g was added, and the mixture was reacted under reflux for 6 hours. Then, the reaction solution was dropped into water to precipitate a polymer, and the precipitated polymer was dried in a vacuum dryer maintained at 40 ° C. for 24 hours. As a result of ¹ H-NMR measurement, the obtained polymer had a structure in which a hydrogen atom of a phenolic hydroxyl group was replaced with a —CH (OCH ₃ ) COOC (CH ₃ ) ₃ group. 20 g of this polymer was dissolved in 250 g of t-butyl alcohol together with 8 g of sodium hydroxide and 20 g of water and reacted under reflux for 6 hours. Then, the reaction solution was dropped into 2 liters of water in which a small amount of hydrochloric acid was dissolved in advance to precipitate a polymer, and the precipitated polymer was separated by filtration, washed thoroughly with water, and then kept in a vacuum dryer maintained at 40 ° C. And dried for 24 hours. The obtained polymer was analyzed by ¹ H-NMR.
As a result of the measurement, the hydrogen atom of the phenolic hydroxyl group was -CH (OCH
₃ ) It has a structure substituted with a COOH group and was easily dissolved in a 2.38 wt% tetramethylammonium hydroxide aqueous solution. This polymer is referred to as an alkali-soluble resin (B).

Synthesis Example 5 26.8 g of the alkali-insoluble resin (b) obtained in Synthesis Example 2
(0.22 mol) was dissolved in 200 g of acetone,
3. Ethyl 2-bromopropionate 10.8 g (0.06 mol), potassium carbonate 8.6 g and potassium iodide 4.
0 g was added, and the mixture was reacted under reflux for 6 hours. Then, the reaction solution was dropped into water to precipitate a polymer, and the precipitated polymer was dried in a vacuum dryer maintained at 40 ° C. for 24 hours. As a result of ¹ H-NMR measurement, the obtained polymer had a structure in which a hydrogen atom of a phenolic hydroxyl group was replaced with a —CH (CH ₃ ) COOC ₂ H ₅ group. 20g of this polymer
Together with 8 g of sodium hydroxide and 20 g of water, t
-Dissolved in 250 g of butyl alcohol and reacted under reflux for 6 hours. Then, the reaction solution was dropped into 2 liters of water in which a small amount of hydrochloric acid was dissolved in advance to precipitate a polymer, and the precipitated polymer was separated by filtration, washed thoroughly with water, and then kept in a vacuum dryer maintained at 40 ° C. And dried for 24 hours. The obtained polymer has a structure in which the hydrogen atom of the phenolic hydroxyl group was replaced with a —CH (CH ₃ ) COOH group as a result of ¹ H-NMR measurement,
It was easily dissolved in a 2.38 wt% tetramethylammonium hydroxide aqueous solution. This polymer is referred to as an alkali-soluble resin (C).

Example 1 10 g of the alkali-soluble resin (A) was dissolved in 40 g of methyl 3-methoxypropionate together with 0.4 g of triphenylsulfonium trifluoromethanesulfonic acid and then filtered through a filter having a pore size of 0.2 μm to prepare a composition. A product solution was prepared. After spin-coating this composition solution on a silicon wafer, use a clean oven at 70 ° C.
Pre-exposure baking was performed for 1 hour to form a resist film having a film thickness of 1.0 μm. A mask pattern is brought into close contact with this resist film, and an excimer laser with a wavelength of 248 μm is set to 90 mJ.
/ Cm ^{2 After} exposure, 130 ° C in clean oven
After 10 minutes of exposure, baking was performed. Then, using a 2.38 wt% tetramethylammonium hydroxide aqueous solution, development was carried out at 25 ° C. for 60 seconds, and then washing with water was carried out for 30 seconds. As a result, a negative line with a resolution of 0.4 μm
The and space pattern was formed in a good pattern shape without swelling. Further, as a result of observation using a scanning electron microscope, no development residue and the like, which were often observed in the conventional cross-linked resist, were observed.

Example 2 10 g of the alkali-soluble resin (B) was added together with 0.4 g of diphenyliodonium hexafluoroantimonate.
After dissolving in 40 g of ethyl 2-hydroxypropionate, it was filtered through a filter having a pore size of 0.2 μm to prepare a composition solution. After spin-coating this composition solution on a silicon wafer, use a clean oven at 100 ° C.
Pre-exposure baking was performed for 1 hour to form a resist film having a film thickness of 1.0 μm. A mask pattern was brought into close contact with this resist film and exposed to an electron beam at 30 μC / cm ^2, and then post-exposure baking, development and washing were carried out in the same manner as in Example 1. As a result, a negative line-and-space pattern having a resolution of 0.3 μm was formed in a good pattern shape without swelling. Moreover, as a result of observation using a scanning electron microscope, no residual developability was observed.

Example 3 10 g of the alkali-soluble resin (C) was dissolved in 35 g of ethyl 2-hydroxypropionate together with 0.4 g of triphenylsulfonium trifluoromethanesulfonic acid and then filtered through a filter having a pore size of 0.2 μm to prepare a composition. A product solution was prepared. After spin-coating this composition solution on a silicon wafer, use a clean oven to
Pre-exposure baking was performed at 1 ° C. for 1 hour to form a resist film having a film thickness of 1.0 μm. A mask pattern is adhered to this resist film, and an excimer laser with a wavelength of 248 μm is used for 90 m.
After J / cm ² exposure, baking was performed after exposure, development and washing were performed in the same manner as in Example 1. As a result, a negative line-and-space pattern having a resolution of 0.5 μm was formed in a good pattern shape without swelling. Moreover, as a result of observation using a scanning electron microscope, no residual developability was observed.

[0068]

EFFECTS OF THE INVENTION The negative-type radiation-sensitive resin composition of the present invention effectively responds to various radiations and can stably perform fine processing of 0.5 μm or less, with high sensitivity and high resolution. It has excellent developability, and also has good pattern shape and adhesiveness. Therefore, the negative-type radiation-sensitive resin composition of the present invention is extremely useful as a resist for producing highly integrated circuits such as semiconductor devices, which are expected to be further miniaturized in the future.

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[Procedure amendment]

[Submission date] August 31, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0038

[Correction method] Change

[Correction content]

Diazoketone compound: 1,3-diketo-2
-Diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds and the like. Preferred diazoketone compounds are
1,2-naphthoquinonediazide-4-sulfonyl chloride, 1,2-naphthoquinonediazide-4-sulfonic acid ester of 2,3,4.4'-tetrahydroxybenzophenone, 1,1,1-tris (4-hydroxyphenyl) ) 1,2-naphthoquinonediazide-4-sulfonic acid ester of ethane and the like.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0054

[Correction method] Change

[Correction content]

After that, a predetermined resist pattern is formed by developing with an alkali developing solution. Examples of the alkaline developer 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, 1,8
-Diazabicyclo- [5.4.0] -7-undecene,
An alkaline aqueous solution in which an alkaline compound such as 1,5-diazabicyclo- [4.3.0] -5-nonene is dissolved in an amount of usually 1 to 10% by weight, preferably 2 to 5% by weight is used. .

Claims (1)

[Claims] 1. An alkali-soluble resin having an acid-dissociable functional group having an action of improving alkali solubility,
A negative-type radiation-sensitive resin characterized by containing a resin in which the acid-dissociable functional group is decomposed by the action of an acid to become alkali-insoluble or sparingly soluble in alkali, and a compound which generates an acid when irradiated with radiation. Composition.