JPH0959379A - Production of polyimide precursor composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyamide precursor composition having an uniform mol.wt. distribution and not producing a rough film in the formation of a pattern by employing processes for successively subjecting a tetracarboxylic dianhydride to ring-opening addition reactions with a diamine, an alcohol and subsequently a diamine in order. SOLUTION: The method for producing a polyimide precursor composition comprises subjecting (A) 100mol.% of a tetracarboxylic dianhydride to a ring- opening addition reaction with (B) 1-99mol.% of a diamine, subjecting (C) the produced polyamic acid oligomer to a ring-opening addition reaction with (D) an alcohol, and further subjecting (E) the produced polyamic acid oligomer having an alcohol ester group at least one of the molecular ends to a ring- opening addition reaction with 99-1mol.% of the component B to produce a polyamic acid in which at least one of substantially equimolar molecular ends is an alcohol ester group (preferably an unsaturated alcohol-acid ester group). The composition preferably further contains a compound (preferably having an amino group) having a photopolymerizable carbon-carbon unsaturated bond, and a photopolymerization initiator.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a novel polyimide precursor composition. More specifically, it relates to a method for producing a novel polyimide precursor composition that can be used for forming a protective film for semiconductor devices, an insulating film for a multilayer wiring board, and the like.

[0002]

2. Description of the Related Art In recent years, in the field of electronics industry, a polyimide obtained by heat-treating a polyamic acid as a polyimide precursor has been used as a protective film or an interlayer insulating film because of its excellent heat resistance and dielectric properties. ing.
However, when a normal polyamic acid is used, a complicated process of using a photoresist is required to form a pattern on the polyimide film. In order to solve this problem, a photosensitive polyimide precursor capable of directly forming a pattern by exposure and development has been proposed.

As a photosensitive polyimide precursor, JP-B-55-30207 and JP-A-60-228537 propose that a photosensitive group is ester-bonded with a carboxyl group in a polyamic acid molecule. Photosensitive polyimide precursor obtained by these production methods, tetracarboxylic dianhydride is reacted with an alcohol containing a carbon-carbon unsaturated bond having photoreactivity to produce a tetracarboxylic acid diester, the diester It is produced by converting the free carboxyl group in the compound into an acid chloride group and subjecting the obtained diester-bis-acid chloride to a polycondensation reaction with a diamine, and thus a purification treatment for removing a chloride as a by-product, and Produced by reacting a tetracarboxylic acid dianhydride with an alcohol having a carbon-carbon unsaturated bond having photoreactivity to form a tetracarboxylic acid diester, and reacting the diester with a diamine in the presence of carbodiimide. Therefore, a purification treatment for separating the by-product urea derivative was required.

As a production method in which these by-products are not produced, an alcohol is ring-opened and added to a tetracarboxylic acid dianhydride to form a tetracarboxylic acid ester anhydride, which is described in JP-A-6-102667. A terminal esterified polyamic acid is formed by ring-opening addition of a diamine to a carboxylic acid ester anhydride or a mixed solution of the tetracarboxylic acid ester anhydride and tetracarboxylic dianhydride, and then a photopolymerization initiator is mixed. There has been proposed a method of producing a photosensitive polyimide precursor by performing the above.

However, also in this method, in the step of ring-opening addition of alcohol to tetracarboxylic acid dianhydride to form tetracarboxylic acid ester anhydride in order to adjust the photosensitive polyimide precursor to an appropriate molecular weight,
This requires a long-time treatment at a high temperature, and it takes a long time to manufacture the photosensitive polyimide precursor. Further, in the molecular weight distribution of the product produced by the method, the low molecular weight distribution was found to be disproportionate, and there was a problem that film roughness was likely to occur when a pattern was formed.

[0006]

DISCLOSURE OF THE INVENTION The present invention was devised in view of the above-mentioned drawbacks of the prior art. The object of the present invention is to prepare tetracarboxylic acid dianhydride in order to adjust the polyimide precursor to an appropriate molecular weight. Shorten the step of forming a tetracarboxylic acid ester anhydride by ring-opening addition of alcohol to the product, and there is no bias in the molecular weight distribution, and
An object of the present invention is to provide a polyimide precursor composition having excellent performance in which no film roughness occurs when a pattern is formed.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
It is achieved by a method for producing a polyimide precursor composition, which comprises at least the following steps A to C.

A. Tetralbonic acid dianhydride 100 mol%
On the other hand, a step of forming a polyamic acid oligomer by ring-opening addition of 1 to 99 mol% of diamine.

B. A step of ring-opening addition of alcohol to the polyamic acid oligomer to form a polyamic acid oligomer in which at least one of the molecular ends is an acid ester of alcohol.

C. The polyamic acid oligomer in which at least one of the molecular ends is an acid ester of an alcohol is subjected to ring-opening addition of 1 to 99 mol% of a diamine, so that at least one of the molecular ends becomes an acid ester of an alcohol. Process of forming polyamic acid that has become.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The details of the method for producing the polyimide precursor composition of the present invention will be described.

First, 1-99 mol% of diamine is added to N-methyl-2 with respect to 100 mol% of tetracarboxylic dianhydride.
-Pyrrolidone, N, N-dimethylacetamide, N, N
-A reaction is carried out in a polar solvent such as dimethylformamide, dimethylsulfoxide, tetramethylurea, hexamethylphosphoric triamide, γ-butyrolactone to obtain a polyamic acid oligomer. The preferable reaction amount of the diamine at this time is 100 mol% of tetracarboxylic dianhydride.
On the other hand, diamine 5 to 80 mol%, more preferably 5 to
60 mol%. When the reaction amount of the diamine is less than 1 mol%, the process of ring-opening addition of alcohol to the following polyamic acid oligomer to form a terminal-esterified polyamic acid oligomer cannot be shortened, and the polyamic acid finally obtained is obtained. From the molecular weight distribution of, a bias toward the low molecular weight distribution can be seen. When the reaction amount of the diamine exceeds 99 mol%, the viscosity of the polyamic acid oligomer becomes remarkably high and stirring is not possible, which is not preferable.

The tetracarboxylic dianhydride has the general formula (1)

Embedded image (R1 in the formula represents the tetravalent organic group described above). In the present invention, as tetracarboxylic dianhydride,
For example, aliphatic or alicyclic compounds can be used, and specific examples thereof include butanetetracarboxylic dianhydride, pentanetetracarboxylic dianhydride, hexanetetracarboxylic dianhydride, cyclobutane. Tetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, bicyclohexenetetracarboxylic dianhydride,
Examples thereof include cyclopropanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride, and methylcyclohexenetetracarboxylic dianhydride. Further, by using an aromatic type, it is possible to obtain a polyimide precursor composition that can be converted into a polyimide having good heat resistance,
Specific examples thereof include 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, pyromellitic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 4, 4'-sulfonyldiphthalic acid dianhydride,
3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-Naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 5,5 ′-(2,2,2) -trifluoro-1- (Trifluoromethyl) ethylene-bis-1,3
-Isobenzofurandione, but not limited to these. In the present invention, one or more of these tetracarboxylic dianhydrides are used.

The diamine is represented by the general formula (2) H2N-R2-NH2 (2) (wherein R2 represents the above divalent organic group), and specific examples thereof include 4, 4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane,
4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, benzidine , 3,3'-dimethylbenzidine,
3,3'-dimethoxybenzidine, o-tolidine, 4,
4 ″ -diaminoterphenyl, 1,5-diaminonaphthalene, 2,5-diaminopyridine, 3,3′-dimethyl-4,4′-diaminodiphenylmethane, 4,4′-bis (p-aminophenoxy) biphenyl, 2,2-bis [4- (p-aminophenoxy) phenyl] propane,
Hexahydro-4,7-methanoindanylene dimethylenediamine and the like can be mentioned, but not limited thereto. In addition, the general formula (3)

Embedded image (R3 in the formula is a divalent organic group having 1 to 10 carbon atoms, R4,
R5, R6, and R7 are monovalent organic groups having 1 to 10 carbon atoms and may be the same or different, and m means an integer of 1 to 10. When the siloxane diamine represented by the formula (1) is used, the adhesion to the inorganic substrate can be improved. Specific examples of the siloxane diamine include bis-3- (aminopropyl) tetramethylsiloxane. In the present invention, one kind or two or more kinds of these diamines are used.

Then, an alcohol is subjected to ring-opening addition to the polyamic acid oligomer to obtain a terminal-esterified polyamic acid oligomer in which at least one of the molecular ends is an acid ester of alcohol.

Alcohol is, for example, a compound represented by the general formula (4) R8-OH (4) (wherein R8 is a C1-15 carbon atom having no unsaturated bond).
C monovalent organic group or unsaturated bond-containing carbon number 3
Represents a monovalent organic group of -15. However, the phenyl group is not directly bonded to the hydroxyl group).

Specific examples of the alcohol having no unsaturated bond include methyl alcohol, ethyl alcohol,
Monohydric alcohols such as isopropyl alcohol and isobutyl alcohol, polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin and trimethylolpropane, methyl cellosolve, ethyl cellosolve,
Examples thereof include, but are not limited to, cellosolves such as butyl cellosolve.

Specific examples of the alcohol having an unsaturated bond include allyl alcohol, 3-allyloxy-1,
2-Propanediol, 2-allyloxyethanol and the like can be mentioned, but when an acrylate ester having an alcoholic hydroxyl group is used, a photosensitive polyimide precursor having good photosensitivity can be obtained. Specific examples thereof include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate,
Examples thereof include polyethylene glycol acrylate, EO-modified phthalic acid acrylate, and those obtained by replacing the above acrylate with methacrylate, but are not particularly limited thereto. Further, these alcohols may be used alone or in combination of two or more.

Alcohol is usually reacted in substantially 0.5 to 200 mol%, preferably 1 to 150 mol% based on tetracarboxylic dianhydride. If the reaction amount of alcohol is too large, the molecular weight of the terminally esterified polyamic acid finally obtained will be small, the amount of dissolution in the developer of the exposed area will be large, and if the amount of dissolution of the exposed area is to be reduced,
A large amount of exposure is required. On the other hand, if the reaction amount of the alcohol is too small, the molecular weight of the terminally esterified polyamic acid finally obtained will be too large, and the solubility of the unexposed portion in the developing solution will be poor. In addition, there is a preferable reaction amount of alcohol depending on the type of alcohol, for example,
It is 1 to 50 mol% for an alcohol having no unsaturated bond such as ethyl alcohol, and 20 to 150 mol% for an acrylate ester having an alcoholic hydroxyl group such as 2-hydroxyethyl acrylate.

These reactions are usually carried out in the temperature range of 0 to 100 ° C, preferably 50 to 80 ° C. If the temperature is too low, the reaction does not proceed easily, and if the temperature is too high, the carbon-carbon unsaturated bond may be cleaved.

Next, by ring-opening addition of 1 to 99 mol% of a diamine to a polyamic acid oligomer in which at least one of the molecular ends is an acid ester of alcohol, at least one of the molecular ends to be substantially equimolar%. A polyamic acid in which is an acid ester of alcohol is obtained. The reaction amount of the diamine at this time is the reaction amount of the diamine used in the step of forming a polyamic acid oligomer in which at least one of the molecular terminals is an acid ester of alcohol by ring-opening addition of an alcohol to the polyamic acid oligomer. It is advisable to mix the total amount of 1 mol% with 100 mol% of the tetracarboxylic dianhydride before the reaction.
If it is 0 to 110 mol%, preferably 95 to 105 mol%, by heat-treating the polyimide precursor,
A polyimide having a high degree of polymerization can be obtained.

The reaction is usually carried out at 0 to 100 ° C.
It is preferably carried out in the temperature range of 50 to 80 ° C. If the temperature is too low, the reaction does not proceed easily, and if the temperature is too high, imidization of the polyamic acid may proceed.

In the present invention, the polyimide precursor composition can be made into a photosensitive polyimide precursor composition by containing a compound having a photoreactive carbon-carbon unsaturated bond and a photopolymerization initiator. .

The compound containing a carbon-carbon unsaturated bond having photoreactivity used in the present invention is not particularly limited, but it is preferable to contain an amino group because the sensitivity is improved. A preferred compound containing a photoreactive carbon-carbon unsaturated bond and an amino group is represented by the general formula (5).

Embedded image (In the formula, R9 is hydrogen or a phenyl group, R10 is hydrogen or a lower alkyl group having 1 to 6 carbon atoms, R11 is a substituted or unsubstituted hydrocarbon group having 2 to 12 carbon atoms, R12, R1.
3 represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms. ) And the general formula (6)

Embedded image (R14 in the formula represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms) or the general formula (7).

Embedded image (R15 in the formula represents hydrogen or a methyl group, and k + 1 =
3, k = 1 to 3. ) And the like. Specific examples thereof include N, N-dimethylaminoethyl acrylate, N, N-diethylaminoethyl acrylate, N, N-dimethylaminopropyl acrylate, N, N-diethylaminopropyl acrylate,
N, N-dimethylaminobutyl acrylate, N, N-
Examples thereof include, but are not limited to, diethylaminobutyl acrylate and those obtained by replacing the above acrylate with methacrylate, 2-vinylpyridine, 4-vinylpyridine, allylamine, 2-methylallylamine, diallylamine and the like. However, in terms of photoreactivity,
An amino compound having an acrylic group or a methacrylic group as the unsaturated group is desirable.

The compound containing a photoreactive carbon-carbon unsaturated bond and an amino group has a carboxyl group in the polyamic acid molecule in which at least one of the molecular ends is an acid ester of alcohol, relative to the carboxyl group. It is desirable to mix ˜2 times molar equivalent, more preferably 0.1 to 1 times molar equivalent. If the amount to be mixed is too small, the photosensitive properties will be poor, and if the amount to be mixed is too large, the amount of decrease in the film thickness will be too large when the polyimide precursor film is heat-treated to form the polyimide film.

The photopolymerization initiator used in the present invention is well known, and specific examples thereof include benzophenone and o-.
Methyl benzoylbenzoate, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, 4,4'-dichlorobenzophenone, 4-benzoyl-4'-methyldiphenyl ketone, dibenzyl ketone , Fluorenone, 2,2'-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2 −
Chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyl dimethyl ketal, benzyl-β-methoxyethyl acetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butyl anthraquinone, 2-amyl anthraquinone, β- Chloranthraquinone, anthrone, benzanthrone, dibenzosuberone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis (p-azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) -4-methyl Cyclohexanone, 1-phenyl-1,2-butanedione-2- (o-methoxycarbonyl) oxime, 1-phenyl-propanedione-2
-(O-ethoxycarbonyl) oxime, 1-phenyl-propanedione-2- (o-benzoyl) oxime,
1,3-Diphenyl-propanetrione-2- (o-ethoxycarbonyl) oxime, 1-phenyl-3-ethoxy-propanetrione-2- (o-benzoyl) oxime, Michler's ketone, N-phenylglycine, 1-hydroxycyclohexyl Phenyl ketone, 2-methyl-
[4- (methylthio) phenyl] -2-morpholino-
1-propanone, naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, 4,4′-azobisisobutyronitrile,
Combination of diphenyl disulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrabromide, tribromophenyl sulfone, benzoyl peroxide and eosin, methylene blue and other photo-reducing dyes with ascorbic acid, triethanolamine and other reducing agents. However, the present invention is not limited to these. In the present invention, these may be used alone or in combination of two or more.

The amount of the photopolymerization initiator contained in the polyimide precursor composition of the present invention is preferably 0.1 to 30% by weight of the polyamic acid in which at least one of the molecular ends is an acid ester of alcohol, 2 to 15% by weight is more preferable. If the amount of the photopolymerization initiator is too small, the photosensitivity of the composition becomes poor, and if the amount of the photopolymerization initiator is too large, the film thickness is reduced when the polyimide precursor film is heat-treated to form the polyimide film. The amount becomes too large.

Photosensitive properties can be improved by adding a photoreactive polymerizable compound containing no amino group to the polyimide precursor composition of the present invention. The photoreactive polymerizable compound is a compound containing a carbon-carbon unsaturated bond having photoreactivity and containing no amino group, and specific examples thereof include allyl acrylate, benzyl acrylate and butoxyethyl. Acrylate, butoxytriethylene glycol acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate,
Dicyclopentenyl acrylate, 2-ethylhexyl acrylate, glycerol acrylate, glycidyl acrylate, heptadecafluorodecyl acrylate,
2-hydroxyethyl acrylate, isobonyl acrylate, 2-hydroxypropyl acrylate, isodecyl acrylate, isooctyl acrylate, lauryl acrylate, 2-methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate , Methoxytriethylene glycol acrylate, methoxydipropylene glycol acrylate, octafluoropentyl acrylate, phenoxyethyl acrylate, stearyl acrylate, trifluoroethyl acrylate, allylated cyclohexyl diacrylate, bisphenol A diacrylate, 1,4 -Butanediol diacrylate, 1,
3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditri Methylolpropane tetraacrylate, glycerol diacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, Triglycerol diacrylate, trimethylolpropane triacrylate and the above Obtained by changing the acrylate to methacrylate, .gamma.-methacryloxypropyl the like trimethoxysilane include, but are not particularly limited thereto.
In the present invention, these may be used alone or in combination of two or more.

When the above-mentioned photoreactive polymerizable compound is added to the polyimide precursor composition of the present invention, the addition amount is 1 to 50% by weight of the polyamic acid in which at least one of the molecular ends is an acid ester of alcohol. % Is preferable, 5
-25% by weight is more preferable. If the amount of the photoreactive polymerizable compound added is too large, the amount of decrease in the film thickness becomes too large when the polyimide precursor film is heat-treated to form the polyimide film. Further, if the added amount is too small, the effect of improving the photosensitivity will not be exhibited.

A sensitizer capable of improving photosensitivity may be added to the polyimide precursor composition of the present invention. Specific examples of the sensitizer include 2,5-bis (4′-diethylaminobenzal) cyclopentanone and 2,6-bis (4
′ -Dimethylaminobenzal) cyclohexanone, 2,
6-bis (4'-dimethylaminobenzal) -4-methylcyclohexanone, 2,6-bis (4'-diethylaminobenzal) -4-methylcyclohexanone, Michler's ketone, 4,4'-bis (diethylamino) -benzophenone , 4,4'-bis (dimethylamino) chalcone, 4,4'-bis (diethylamino) chalcone, p-
Dimethylaminocinnamylidene indanone, p-dimethylaminobenzylidene indanone, 2- (p-dimethylaminophenylvinylene) benzothiazole, 2- (p
-Dimethylaminophenylvinylene) -isonaphthothiazole, 1,3-bis (4'-dimethylaminobenzal) acetone, 1,3-bis (4'-diethylaminobenzal) acetone, 3,3'-carbonyl-bis (7-
Diethylaminocoumarin), N-phenyl-N'-ethylethanolamine, N-phenyldiethanolamine, N-tolyldiethanolamine, N-phenylethanolamine, dimethylaminobenzoic acid isoamyl, diethylaminobenzoic acid isoamyl, 3-phenyl-5-
Examples thereof include isoxazolone, 1-phenyl-5-benzoylthio-tetrazole and 1-phenyl-5-ethoxycarbonylthio-tetrazole, but are not particularly limited thereto. In the present invention, one kind or two or more kinds of these sensitizers can be used. Some sensitizers also act as photopolymerization initiators.

When the sensitizer is added to the polyimide precursor composition of the present invention, the addition amount is 0.1 to 30% by weight of the polyamic acid in which at least one of the molecular ends is an acid ester of alcohol. Preferably, 0.5 to 15% by weight is more preferable. If the added amount is too large, when the polyimide precursor film is heat-treated to form the polyimide film,
The amount of decrease in film thickness becomes too large. Further, if the addition amount is too small, the effect of improving the photosensitivity cannot be exhibited.

A thermal polymerization inhibitor may be added in order to improve the thermal stability of the polyimide precursor composition of the present invention during storage. Specific examples of the thermal polymerization inhibitor include hydroquinone, N-nitrosodiphenylamine,
Examples thereof include phenothiazine, pt-butylcatechol, N-phenylnaphthylamine, 2,6-di-t-butyl-p-methylphenol, chloranil, and pyrogallol, but are not particularly limited thereto. When the thermal polymerization inhibitor is added, the addition amount thereof is preferably 0.1 to 20% by weight, more preferably 0.5 to 10% by weight, of the polyamic acid in which at least one of the molecular ends is an acid ester of saturated alcohol. preferable. If the added amount is too large, when the polyimide precursor film is heat-treated to form the polyimide film,
The amount of decrease in film thickness becomes too large. If the amount added is too small, the effect of improving the thermal stability during storage will not be exhibited.

Further, a colloidal substance of inorganic fine particles may be added to the polyimide precursor composition of the present invention in order to improve the hardness of the polyimide film. Specific examples of the colloidal substance of inorganic fine particles include silica sol, titania sol, zirconia sol, etc., but are not particularly limited thereto. When the colloidal substance of inorganic fine particles is added, the addition amount is 1 to 50 of the polyamic acid in which at least one of the molecular ends is an acid ester of alcohol.
Weight% is preferable, and 2-30 weight% is more preferable.
If the amount added is too large, the pattern workability of the polyimide precursor film will deteriorate, and if the amount added is too small, the effect of improving the hardness of the polyimide film will not be exhibited.

The polyimide precursor composition of the present invention contains all components constituting the composition, or when additives are added, other than those basically insoluble in organic solvents such as colloidal particles of inorganic fine particles. A varnish for application can be obtained by dissolving all the components including the additive of 1. in an organic solvent capable of dissolving the components. The organic solvent is preferably used when synthesizing the polyamic acid in which at least one of the molecular ends is an acid ester of alcohol,
The same organic solvent as that capable of dissolving the polyamic acid can be used.

As a method for applying this varnish on the substrate, a method for applying the varnish on the substrate by a spin coater, a bar coater, a blade coater, a screen printing method, a method for immersing the substrate in the varnish, or a method for spraying the varnish on the substrate Various methods such as can be used. As a substrate,
Semiconductors such as silicon and gallium-arsenic, inorganic insulators such as alumina ceramics and glass ceramics, metals such as aluminum and copper, and organic insulators such as polyester films can be selected. In addition, when applying varnish on a substrate made of a semiconductor, an inorganic insulator, or a metal,
If the substrate surface is treated with an adhesion aid such as a silane coupling agent, an aluminum chelating agent, or a titanium chelating agent, the adhesion between the polyimide and the substrate can be improved.

After the varnish is applied on the substrate, the polyimide precursor film is formed by air drying, heat drying, vacuum drying or the like.

The film obtained from the photosensitive polyimide precursor composition is exposed using an ordinary photomask. Examples of the actinic rays used at this time include ultraviolet rays,
Examples thereof include electron beams and X-rays. Among these, ultraviolet rays are preferable, and examples of the light source thereof include a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a halogen lamp, and a germicidal lamp. Among these light sources, an ultra-high pressure mercury lamp is preferred. Also, the exposure is performed in a nitrogen atmosphere, or
It is preferably carried out in vacuum.

After exposure, development is performed using a developing solution.
In this case, a dipping method or a spray method can be used.
As the developer, usually, the same as the above-mentioned organic solvent capable of dissolving the polyamic acid, which is preferably used when synthesizing the polyamic acid in which at least one of the molecular terminals is an acid ester of alcohol, is used. used. In addition,
Water may be added to such an organic solvent in order to improve the developability. When water is added, its amount is usually 1 to 100% by weight, preferably 5 to 50% by weight, based on the organic solvent. If the added amount is too large, phase separation may occur with the organic solvent, and if the added amount is too small, the effect of improving the developability is not exhibited. Immediately after development, ethyl alcohol, isopropyl alcohol, isobutyl alcohol,
Rinsing is preferably performed with an organic solvent such as hexane or pentane.

The polyimide precursor pattern obtained by development is then converted into a polyimide pattern by heat treatment. The heat treatment is usually performed in a nitrogen atmosphere or in vacuum at a temperature of 150 to 450 ° C. for 0.5 to 5 hours.

A film obtained from a non-photosensitive polyimide precursor composition is coated with a positive photoresist, prebaked, and then exposed using a photomask. After exposure, the resist is developed with a photoresist developing solution. It is developed at the same time. After development, the resist is peeled off to form a pattern of the polyimide precursor. By subjecting this to heat treatment, a polyimide pattern is obtained.

The polyimide film thus obtained can be used as a semiconductor protective film, an interlayer insulating film, a protective film for electronic parts, an interlayer insulating film for multi-layer wiring, and the like.

[0042]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 100 equipped with a thermometer and a dry air inlet and a stirrer
In a 0 ml four-necked flask, 147.1 g (0.5 mol) of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether 40.0
g (0.2 mol) and N-methyl-2-pyrrolidone (317.3 g) were charged, and the mixture was stirred at 60 ° C. for 1 hour under an inflow of dry air. Subsequently, 2.3 g of ethyl alcohol (0.
(05 mol), and further stirred at 60 ° C. for 1 hour. Then, the mixture was cooled to room temperature and 10.0 g (0.05 mol) of 4,4′-diaminodiphenyl ether, 24.3 g (0.255 mol) of paraphenylenediamine, and bis-3- (aminopropyl) tetramethylsiloxane 6. 2 g (0.
025 mol), and 211.5 g of γ-butyl lactone.
Was added, and the mixture was stirred at 60 ° C. for 3 hours under a flow of dry air to obtain a polyimide precursor solution having a viscosity of 150 poise.

Next, 79.5 g of diethylaminoethyl methacrylate, 11.4 g of N-phenylglycine and 6-N-methyl-2-pyrrolidone 6 were added to the polyimide precursor solution.
0.4 g was added, and the mixture was stirred and mixed, and then filtered through a filter to obtain a photosensitive polyimide precursor solution having a viscosity of 65 poise.

The molecular weight and molecular weight distribution of this solution were measured by gel permeation chromatography, GPC-244 (WATERS).
The number average molecular weight was 9200 as measured by. The polydispersity of weight average molecular weight / number average molecular weight, which is an index of the spread toward the low molecular weight side, was 1.71.

This solution was spin-coated on a 4-inch silicon wafer and heated and dried at 80 ° C. for 1 hour to give a thickness of 3
A 0 μm film was formed. Pattern mask this film surface,
Exposure is carried out for 30 seconds using an ultra-high pressure mercury lamp with an output of 7 mw / cm ² , and then it is immersed in a 7: 2: 1 (weight ratio) mixture of N-methyl-2-pyrrolidone, xylene and water, The film was developed until the unexposed portion was dissolved and removed (at this time, the time required for development was 2 minutes), and rinsed with isopropyl alcohol. As a result, a polyimide precursor solution film with a thickness of 28 μm and no film roughness was observed. Got the pattern.
In a nitrogen atmosphere, this is heated to 200 ° C, 300 ° C, 400
Each heat treatment was performed at 30 ° C. for 30 minutes to obtain a polyimide pattern having a thickness of 14 μm.

Comparative Example 1 100 equipped with a thermometer and a dry air inlet and a stirrer
In a 0 ml four-necked flask, 147.1 g (0.5 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2.3 g (0.05 mol) of ethyl alcohol and N-methyl- Charge 317.3 g of 2-pyrrolidone,
The mixture was stirred at 70 ° C. for 3 hours while flowing dry air. Thereafter, the mixture was cooled to room temperature, and 50.0 g (0.25 mol) of 4,4'-diaminodiphenyl ether, 24.3 g (0.255 mol) of paraphenylenediamine, bis-3- (aminopropyl) tetramethylsiloxane 6. 2 g (0.025
Mol) and 211.5 g of γ-butyrolactone were added, and the mixture was stirred at 60 ° C. for 3 hours under a flow of dry air to give a viscosity of 1
A 50 poise polyimide precursor solution was obtained.

Next, 79.5 g of diethylaminoethyl methacrylate, 11.4 g of N-phenylglycine and 60.4 g of N-methyl-2-pyrrolidone were added to the polyimide precursor solution, and after stirring and mixing, the mixture was filtered with a filter to obtain a viscosity. A 65 poise photosensitive polyimide precursor solution was obtained.

The molecular weight and molecular weight distribution of this solution were measured by gel permeation chromatography, GPC-244 (WATERS).
The number average molecular weight was 9,000, but the polydispersity index of the weight average molecular weight / number average molecular weight, which is an index of the spread to the low molecular weight side, was 2.31, which was determined from Example 1. It was a big one.

When a pattern was formed in the same manner as in Example 1, white and a flow pattern were observed on the film surface although the film thickness was the same.

Example 2 100 equipped with a thermometer and dry air inlet and a stirrer
In a 0 ml four-necked flask, 147.1 g (0.5 mol) of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether 40.0
g (0.2 mol) and N-methyl-2-pyrrolidone (280 g) were charged, and the mixture was stirred at 60 ° C. for 1 hour while flowing dry air. Subsequently, 65.1 g (0.5 mol) of 2-hydroxyethyl methacrylate was added, and the mixture was further stirred at 60 ° C. for 3 hours. Then, the mixture was cooled to room temperature and 10.0 g (0.05 mol) of 4,4'-diaminodiphenyl ether, 24.3 g (0.255 mol) of paraphenylenediamine,
6.2 g (0.025 mol) of bis-3- (aminopropyl) tetramethylsiloxane and 186 g of γ-butyl lactone were added, and the mixture was stirred at 60 ° C. for 3 hours under a flow of dry air to obtain a polyimide precursor having a viscosity of 160 poises. A body solution was obtained.

Next, 79.5 g of diethylaminoethyl methacrylate, 11.4 g of N-phenylglycine and 60.4 g of N-methyl-2-pyrrolidone were added to the polyimide precursor solution, and after stirring and mixing, the mixture was filtered with a filter to obtain a viscosity. A 70 poise photosensitive polyimide precursor solution was obtained.

The molecular weight and molecular weight distribution of this solution were measured by gel permeation chromatography, GPC-244 (WATERS).
The number average molecular weight was 9500, and the polydispersity index of the weight average molecular weight / number average molecular weight, which is an index of the spread to the low molecular weight side, was 1.82.

When a pattern was formed in the same manner as in Example 1, no film roughening was observed.

Comparative Example 2 100 equipped with a thermometer and a drying air inlet equipped with a stirrer
147.1 g (0.5 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 65.1 g of 2-hydroxyethyl methacrylate were placed in a 0 ml four-necked flask.
(0.5 mol) and N-methyl-2-pyrrolidone 28
0 g was charged, and the mixture was stirred at 70 ° C. for 5 hours while flowing dry air. Then, it cooled to room temperature, 4,4'- diamino phenyl ether 50.0 g (0.25 mol), paraphenylenediamine 24.3 g (0.025 mol), bis-3
6.2 g of-(aminopropyl) tetramethylsiloxane
(0.025 mol), and γ-butyl lactone 186
g, and stirred under a flow of dry air at 60 ° C. for 3 hours,
A polyimide precursor solution having a viscosity of 160 poise was obtained.

Next, 79.5 g of diethylaminoethyl methacrylate, 11.4 g of N-phenylglycine and 60.4 g of N-methyl-2-pyrrolidone were added to the polyimide precursor solution, and after stirring and mixing, the mixture was filtered with a filter to obtain a viscosity. A 70 poise photosensitive polyimide precursor solution was obtained.

The molecular weight and molecular weight distribution of this solution were measured by gel permeation chromatography, GPC-244 (WATERS).
The number average molecular weight was 9200, but the polydispersity index of the weight average molecular weight / number average molecular weight, which is an index of the spread to low molecular weight, was 3.18.
It was bigger.

When a pattern was formed in the same manner as in Example 1, white and flow patterns were observed on the film surface.

Example 3 In Example 2, 2-hydroxyethyl methacrylate 65.
Example 2 was repeated except that 58.1 g (0.5 mol) of 2-hydroxyethyl acrylate was used instead of 1 g (0.5 mol), and the number average molecular weight was 9300.
The polydispersity of weight average molecular weight / number average molecular weight, which is an index of the spread to the low molecular weight side, was 1.84.

When a pattern was formed in the same manner as in Example 1, no film roughening was observed.

[0061]

The steps of ring-opening addition of alcohol to tetracarboxylic dianhydride to form tetracarboxylic acid ester anhydride can be shortened. In addition, it is possible to obtain a polyimide precursor composition which has a good molecular weight distribution and is excellent in performance in which a film is not roughened when a pattern is formed.

Claims (5)

[Claims] 1. A method for producing a polyimide precursor composition, which comprises at least the following steps A to C: A. A step of forming a polyamic acid oligomer by ring-opening addition of 1 to 99 mol% of diamine to 100 mol% of tetralbonic acid dianhydride. B. A step of ring-opening addition of alcohol to the polyamic acid oligomer to form a polyamic acid oligomer in which at least one of the molecular ends is an acid ester of alcohol. C. Diamine 1 is added to the polyamic acid oligomer in which at least one of the molecular ends is an acid ester of alcohol.
A step of forming a polyamic acid in which at least one of the molecular ends is an acid ester of alcohol, which is substantially equimolar% by ring-opening addition of ˜99 mol%. 2. The method for producing a polyimide precursor composition according to claim 1, wherein at least one of the molecular ends of the polyamic acid is an acid ester of unsaturated alcohol. 3. The method for producing a polyimide precursor composition according to claim 2, wherein the unsaturated alcohol is an acrylate ester having an alcoholic hydroxyl group. 4. The polyimide precursor composition according to claim 1, wherein the polyimide precursor composition contains a compound having a photoreactive carbon-carbon unsaturated bond and a photopolymerization initiator. Production method. 5. The method for producing a polyimide precursor composition according to claim 4, wherein the compound having a carbon-carbon unsaturated bond having photoreactivity has an amino group.