JP2000131841A - Photosensitive polyimide precursor composition and metal foil-polyimide composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive polyimide precursor composition in the polyimide composite material comprising the polyimide and a metal material by incorporating the composition of a specified polymer and a photopolymerization initiator and and controling an average linear expansion ecoefficient after curing in a specified temperature range in a specified range. SOLUTION: The photosensitive composition comprises the polymer represented by the formula and the polymerization initiator and the average linear expansion coefficient is 10×10-6-30×10-6/ deg.C after curing in the range of 30-100 deg.C. In the formula, R1 is a tetravalent aromatic acid group; R2 is an aromatic diamine group containing >=60% diaminobenzanilide group; R3 is one of -OR4 and -NHR4 and -O-N+R4R5R6R7 group or a mixture of them and -OH group; R4 is a group having at least one ethylenically unsaturated bond; each of R5-R7 is an H atom or a 1-10C hydrocarbon group; and (n) is 1 or 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive polyimide precursor composition and a metal foil-polyimide composite using the same.

[0002]

2. Description of the Related Art Conventionally, a photosensitive polyimide precursor varnish is disclosed in JP-B-59-52822, which is a polymer containing polyamic acid as a main component, an amine compound having a carbon-carbon double bond, and a sensitizer added if necessary. A photosensitive polyimide precursor composition in which a photosensitive group is introduced into a polyamic acid by an ester group as disclosed in JP-A-61-293204, or a polymer terminal as disclosed in JP-A-8-95247. It is known to add a photosensitive auxiliary having a photopolymerizable functional group to a polyimide precursor having a functional group introduced therein. These materials are used in a varnish state dissolved in an organic solvent. This varnish is applied to a substrate and dried to form a film, which is then irradiated with ultraviolet light through an appropriate photomask, developed and rinsed to obtain a desired relief pattern, and further heat-treated to have high heat resistance. A relief pattern of the photosensitive polyimide film can be formed.

[0003]

However, the known polyimide composite material comprising a polyimide film and a metal material has a problem that the aromatic polyimide forming the aromatic polyimide film has a considerably large linear expansion relative to the metal material. Due to having a coefficient, there is a disadvantage that curling occurs when the polyamic acid is heat-treated to be polyimide. Also,
Also in the field of semiconductors, there is a drawback that when the thickness of the polyimide film is increased, the silicon wafer as the substrate is warped. Alternatively, since the aromatic polyimide does not have sufficient physical properties such as mechanical strength, heat resistance, and flexibility, the obtained product cannot be used as an electric or electronic material.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and has as its object to have no problems in mechanical strength, heat resistance, flexibility, etc., to have a low linear expansion coefficient, It is a further object of the present invention to provide a photosensitive polyimide precursor composition capable of performing a good patterning process, without curling in a polyimide composite material composed of a polyimide and a metal material, and also increasing the thickness of the polyimide in the field of semiconductors. Even in such a case, the warpage of the silicon wafer as the substrate is suppressed.

[0005]

SUMMARY OF THE INVENTION The present invention provides a photosensitive polyimide precursor composition comprising (A) a polymer represented by the following general formula (1) and (B) a photopolymerization initiator. A photosensitive polyimide precursor composition, characterized in that the composition has an average linear expansion coefficient at 30 ° C to 100 ° C of 10 × 10 ⁻⁶ / ° C to 30 × 10 ⁻⁶ / ° C. A metal foil-polyimide composite obtained by applying the photosensitive polyimide precursor composition on a foil so that the film thickness after curing is 5 to 30 μm, and warping the composite after curing. The value is 80 × 10 ⁻³ or less, and when formed in a pattern, the warpage coefficient of the cured composite is 15 × 1
Metal foil characterized in that it is a ^0-3 - is a polyimide composite.

[0006]

Embedded image (In the general formula (1), R ¹ is a tetravalent aromatic acid residue, and R ² is 6
0 mol% or more represents an aromatic diamine residue which is a diaminobenzanilide residue, and R ³ represents —OR ⁴ , —NHR ⁴ ,
^{O - N + R 4 R 5} R 6 group selected from R ^7, or shows a mixture of these radicals and -OH. Where R ⁴ is at least 1
Groups having ethylenically unsaturated bonds, R ⁵ ,
R ⁶ and R ⁷ each represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. n is 1 or 2. )

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
In the present invention, the cured polyimide precursor composition has an average coefficient of linear expansion at 30 ° C. to 100 ° C. of 10 × 10 ^−6.
/ A to 30 × 10 ^-6 / ° C (A) The following general formula (1)
Is used.

[0008]

Embedded image In the general formula (1), R ¹ is a tetravalent aromatic acid residue, and R ² is 60
The aromatic diamine residue in which at least mol% is diaminobenzanilide is shown, and R ³ is —OR ⁴ , —NHR ⁴ , —O ⁻ N ⁺
A group selected from R ⁴ R ⁵ R ⁶ R ⁷ , or
Shows mixing with OH. Here, R ⁴ represents a group having at least one kind of ethylenically unsaturated bond, and R ⁵ , R ⁶ and R ⁷ each represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. n is 1 or 2.

When a photosensitive polyimide precursor composition in which the proportion of diaminobenzanilides is reduced and the aromatic diamine component containing an ether bond in the molecule is increased is applied to a metal foil, the warpage of the resulting composite material is increased. Become. In addition, the elongation in a tensile test of a polyimide film formed from a photosensitive polyimide precursor composition having a diaminobenzanilide ratio close to 100 mol% is reduced, or the polyimide film is formed from a photosensitive polyimide precursor composition obtained. The adhesion between the polyimide film and a substrate such as a silicon wafer or a metal foil is lowered, and the polyimide film cannot be used as an electric or electronic material. Accordingly, 60 mol% or more of the aromatic diamine residue of R ^{2 in} the general formula (1) is composed of a diaminobenzanilide residue. Furthermore, 60 to aromatic diamine residues
~ 95 mol% are diaminobenzanilide residues,
It is preferable that ％ 40 mol% is an aromatic diamine residue containing an ether bond in the molecule.

In the aromatic acid residue of the present invention, if the proportion of the pyromellitic acid residue is too large, the obtained polyimide film becomes brittle, and the elongation in a tensile test decreases. Accordingly, 10 to ¹ relative to the aromatic acid residue of R ^{1 in} the general formula (1)
00 mol% of biphenyltetracarboxylic acid residues and 0-9
It is preferably composed of 0 mol% of pyromellitic acid residues.

The diaminobenzanilides in the present invention include 4,4'-diaminobenzanilide,
Examples thereof include 4'-diaminobenzanilide and 4,3'-diaminobenzanilide. Examples of the aromatic diamine component containing an ether bond in the molecule include 4,4'-diaminodiphenyl ether and 3,4'-diaminodiphenyl ether. 3,3′-diaminodiphenyl ether, 1,4-bis (4-aminophenoxy) benzene,
1,3-bis (4-aminophenoxy) benzene, 4,
Examples include 4′-bis (4-aminophenoxy) biphenyl and bis [4- (4-aminophenoxy) phenyl] ether, but are not limited thereto. Examples of the biphenyltetracarboxylic acids in the present invention include 2,3,3 ′, 4′-biphenyltetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, and anhydrides thereof. Is not limited to these.

The method for polymerizing a compound of the general formula (1) wherein R ³ is —OR ⁴ (R ⁴ is the same as described above) includes an acid dianhydride and one kind of alcohol having an ethylenically unsaturated bond. And then reacting with a diamine using a carbodiimide-based condensing agent. It can also be obtained by reacting an acid dianhydride with a diamine and then reacting it with one type of epoxy compound having an ethylenically unsaturated bond. Specific examples of the compound for esterification include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, allyl alcohol, ethylene glycol monoallyl ether, and the like. Specific examples of the latter esterification include, but are not limited to, glycidyl methacrylate, glycidyl acrylate and the like. Further, as the polymerization method of the compound wherein R ³ is -O ^{over N + R 4 R 5 R 6} R 7 (R 4, R 5, R 6, R 7 are as defined above) of the general formula (1) Is a polyamic acid obtained by reacting an acid dianhydride and a diamine, and mixing one type of amine having an ethylenically unsaturated bond,
It can be obtained by ionic bonding to the carboxyl group of amic acid.

Specific examples of the amine compound include N,
N-dimethylaminoethyl acrylate, N, N-diethylaminoethyl acrylate, N, N-dimethylaminopropyl acrylate, N, N-diethylaminopropyl acrylate, N, N-dimethylaminobutyl acrylate, N, N-diethylaminobutyl acrylate and N , N-dimethylaminoethyl methacrylate,
N, N-diethylaminoethyl methacrylate, N, N
-Dimethylaminopropyl methacrylate, N, N-diethylaminopropyl methacrylate, N, N-dimethylaminobutyl methacrylate, N, N-diethylaminobutyl methacrylate, N, N-dimethylaminoethyl methacrylamide, N, N-dimethylaminopropyl methacrylamide , N, N-diethylaminoethyl methacrylamide, N, N-diethylaminopropyl methacrylamide, N, N-dimethylaminoethylacrylamide, N, N-diethylaminopropylacrylamide, 2-vinylpyridine, 4-vinylpyridine, allylamine, 2- Examples include methylallylamine and diallylamine, but are not particularly limited thereto.

In the general formula (1), R ³ is —NHR ⁴ (R
⁽⁴ is the same as described above)) is a method for polymerizing a polyamic acid obtained by reacting an acid dianhydride and a diamine with an isocyanate having one kind of ethylenically unsaturated bond in the presence of a base catalyst. And can be obtained by reacting Specific examples of this compound include isocyanate ethyl acrylate, isocyanate propyl acrylate, isocyanate butyl acrylate, isocyanate pentyl acrylate, isocyanate hexyl acrylate, isocyanate octyl acrylate, isocyanate decyl acrylate, isocyanate pentyl acrylate, isocyanate ethyl methacrylate, isocyanate propyl methacrylate, isocyanate butyl Examples include methacrylate, isocyanate pentyl methacrylate, isocyanate hexyl methacrylate, isocyanate octyl methacrylate, and isocyanate decyl methacrylate, but are not particularly limited thereto. Among these, -O ^{over N + R 4 R 5 R 6} R 7 is a volatile prone ionic bonding type photosensitive agent in the curing is preferred as R ^3.

The ethylenically unsaturated bonding group is preferably present in a molar equivalent of 0.1 to 1 times the carboxyl group in the polyimide precursor composition. If the mixing amount is too small, the photosensitive characteristics will be poor, and if the mixing amount is too large,
When a polyimide precursor film is applied to a metal foil and heat-treated to form a polyimide film, the warpage of the composite material increases, or the amount of decrease in the film thickness increases.

The polyamic acid for introducing an ethylenically unsaturated group by an ionic bond, an amide bond or an ester bond used in the present invention is obtained by adding the above-mentioned tetracarboxylic acid component and diamine component to the total molar equivalent of tetracarboxylic acid. On the other hand, 0.9 to 1.1-fold molar equivalent, preferably 0.1 to 1.1-fold molar equivalent.
95 to 1.05 times molar equivalent, more preferably equimolar equivalent is used, and becomes a high molecular weight in a polar organic solvent at a temperature of 0 to 100 ° C, preferably 10 to 80 ° C for 0.2 to 60 hours. It is produced by polymerizing as follows.

In this production method, the smaller the difference between the molar equivalents, the greater the degree of polymerization of the polyimide obtained by heating the polyimide precursor, and a film having good mechanical properties can be obtained. It is preferable to use the carboxylic acid component and the aromatic diamine component in equimolar amounts. At the polymerization temperature, if the temperature is too low, the reaction does not proceed easily, and if the temperature is too high, the imidization of the polyamic acid may proceed.
It is preferred that the polymerization be carried out within a range of from -80 ° C.

When an ethylenically unsaturated bond is introduced by an ionic bond, the above-mentioned amine having an unsaturated bond is added to the polyamic acid obtained by the above polymerization at room temperature, and a photopolymerization initiator and, if necessary, further increase. By adding a sensitizer, a polyimide precursor composition is obtained.

When the ethylenically unsaturated bond is introduced by an amide bond, the above-mentioned isocyanate having an unsaturated bond is added to the polyamic acid obtained by the above polymerization in the presence of a basic catalyst such as an amine at 0 to 100 ° C. Preferably 20 to
After the reaction at 70 ° C. in the organic solvent used for the polymerization, a photopolymerization initiator and, if necessary, a sensitizer are added to obtain a polyimide precursor composition.

When the ethylenically unsaturated bond is introduced by an ester bond, the above-mentioned epoxy compound having an unsaturated bond is preferably added to the polyamic acid obtained by the above polymerization at 60 to 120 ° C. in the presence of a basic catalyst such as an amine. Is 70-9
After the reaction at 0 ° C. in the organic solvent used for the polymerization, a photopolymerization initiator and, if necessary, a sensitizer are added to obtain a polyimide precursor composition.

Another method for producing a polyamic acid for introducing an ethylenically unsaturated group through an ester bond is a method for producing a polyamic acid by reacting the above-mentioned tetracarboxylic acid with an alcohol having an ethylenically unsaturated bond. It can be obtained by reacting a carboxylic acid diester with the above-mentioned diamine component in the presence of a condensing agent, and the reaction conditions are not particularly limited. The reaction temperature in this case is not particularly limited as long as the reaction proceeds, but is preferably −20 ° C. to 80 ° C., and more preferably −10 ° C. to 30 ° C., from the viewpoint of the reaction rate and the generation of by-products. . The ratio of the condensing agent may be at least equivalent to the smaller amount of carboxylic acid or amine, and there is no particular problem even if it is present in excess. Usually, it is preferable to use about 1 to 1.5 equivalents. The reaction time is preferably from 10 minutes to 100 hours, more preferably from 1 hour to 24 hours. In addition, the reaction can be smoothly performed using an additive such as 1-hydroxybenzotriazole or pyridine during the reaction. The molar ratio of the tetracarboxylic acid diester to the diamine is 0.7 to 1.3 times the molar equivalent of the total amount of the tetracarboxylic acid depending on the molecular weight of the desired polyamic acid, and preferably the molar equivalent is used. It is manufactured by doing. The generated polyamic acid is crystallized in water or an organic solvent, and is filtered using a known method such as filtration, washing, reprecipitation with water or an organic solvent, a residual condensing agent, and a urea product from the condensing agent. Purified by removing species and the like. A polyimide precursor composition can be obtained by dissolving all the components including the purified polyamic acid, the photopolymerization initiator and, if necessary, the sensitizer in a soluble organic solvent.

The photopolymerization initiator used in the present invention is not particularly limited. Specific examples thereof include benzophenone, o-
Methyl benzoylbenzoate, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, 4,4'-dichlorobenzophenone, 4-benzoyl-4'-methyldiphenylketone, dibenzylketone , Fluorenone, 2,2'-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, −
Chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyldimethyl ketal, benzyl-β-methoxyethyl acetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-t-butylanthraquinone, 2-amylanthraquinone, 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, 3-phenyl- 5-isoxazolone, 1-hydroxycyclohexylphenyl ketone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, naphthalenesulfonyl chloride, quinoline sulfonyl chloride, N-phenylthioacridone,
Photoreducing dyes such as 4,4'-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrabromide, tribromophenyl sulfone, benzoyl peroxide and eosin, and methylene blue; Examples include, but are not particularly limited to, combinations of reducing agents such as ascorbic acid and triethanolamine. In the present invention, one or more of these can be used.

The amount of the photopolymerization initiator contained in the photosensitive polyimide precursor composition of the present invention is 0.1% of the polyamic acid.
-30% by weight is preferred, and 0.3-15% by weight is more preferred. 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,
When the polyimide precursor film is heat-treated to form a polyimide film, the amount of decrease in the film thickness is too large.

A sensitizer capable of improving photosensitivity may be added to the photosensitive polyimide precursor composition of the present invention. As a specific example of the sensitizer, 2,5-bis (4′-
Diethylaminobenzal) cyclopentanone, 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'-diethylamino) Benzal) acetone, 3,3'-carbonyl-
Bis (7-diethylaminocoumarin), N-phenyl-
N'-ethylethanolamine, N-phenyldiethanolamine, N-tolyldiethanolamine, N-phenylethanolamine, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 3-phenyl-5-isoxazolone, 1-phenyl-5-benzoyl Examples include thiotetrazole and 1-phenyl-5-ethoxycarbonylthiotetrazole, but are not particularly limited thereto. In the present invention, one or more of these sensitizers can be used. Some of the sensitizers also act as photopolymerization initiators.

When a sensitizer is added to the photosensitive polyimide precursor composition of the present invention, the amount added is preferably 0.1 to 30% by weight of the polyamic acid, more preferably 0.3 to 15% by weight. . If the addition amount is too large, the amount of decrease in the film thickness becomes too large when the polyimide precursor film is heat-treated to form a polyimide film. On the other hand, if the addition amount is too small, the effect of improving the photosensitivity is not exhibited.

The polar organic solvent used in the above production method has a boiling point of 300 ° C. or less at normal pressure, especially 250 ° C.
The following are preferable, for example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, N, N-diethylacetamide,
N, N-diethylformamide, dimethylsulfoxide, dimethylsulfone, γ-butyrolactone and the like can be preferably mentioned, but not limited thereto. In addition, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons, etc. which are common organic solvents other than these polar solvents, such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, Ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate, diethyl ether,
Ethylene glycol dimethyl ether, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,
It can be used by mixing with 4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene and the like.

The photosensitive polyimide precursor composition of the present invention has an average coefficient of linear expansion at 30 ° C. to 100 ° C. after curing which is from 10 × 10 ⁻⁶ / ° C. to 30 × 10 ⁻⁶ / ° C. This is very important. This average linear expansion coefficient is 30 × 10
^In the case of ^-6 / ° C. or higher, a curling problem occurs in the metal material-polyimide composite because the metal material has a larger linear expansion coefficient than the metal material. Tends to become more pronounced as the thickness of the layer increases. Also, in the field of semiconductors, there is a problem that as the film thickness of polyimide increases, the silicon wafer is warped. In the measurement of the average linear expansion coefficient in the present invention, the photosensitive polyimide precursor composition is cured,
A polyimide film having a thickness of 0 μm, a width of 1.5 mm, and a thickness of 15 mm is used.

The coefficient of linear expansion was measured at a thickness of 10 μm.
A polyimide film having a width of 15 mm and a length of 30 mm is wound into a cylindrical shape in the longitudinal direction, and TMA / SS- manufactured by Seiko Electronics Co., Ltd.
6000 at a rate of 5 ° C /
Measured in minutes.

The warp in the present invention uses a metal foil-polyimide composite in which a photosensitive polyimide precursor composition is cured on a 25 μm SUS foil and a 10 μm thick polyimide film is formed. The cured metal foil-polyimide composite is obtained by allowing the composite to stand on a horizontal plane, and dividing the height of the corner of the composite from the horizontal plane by the length of the SUS foil in the longitudinal direction. The measurement of the warpage value was performed by measuring an unpatterned metal foil-polyimide composite at 20 to 30 ° C and 30 to 70 ° C.
Under% RH, the cured composite was placed on a horizontal plane, and the height of the corner from the horizontal plane was measured with a vernier caliper. In addition, the measurement of the warpage coefficient was performed by measuring the metal foil-polyimide composite formed in a pattern at 20 to 30 ° C and 30 to 7 ° C.
When one of the composites was fixed to the reference plane at 0% RH, the height of the composite from the other reference plane was determined by measuring with a vernier caliper or 1LM21 manufactured by Lasertec.

As a method of applying the obtained composition on a substrate, a method of applying the composition to the substrate by a spin coater, a bar coater, a blade coater, a reverse coater, a screen printing method, or the like, a method of dipping the substrate in a varnish, Various methods such as spraying a varnish onto a substrate can be used, but the method is not limited thereto. As the substrate, a metal foil having a thickness of 5 to 100 μm, preferably 5 to 30 μm
μm metal foil, more preferably 10-30 μm stainless steel foil, after applying the photosensitive polyimide precursor composition on a substrate so that the film thickness after curing is 5-30 μm, air drying, heat drying Forming a photosensitive polyimide precursor film by vacuum drying or the like, and continuously or stepwise forming the film in a nitrogen atmosphere or in a vacuum at a temperature of 150 to 450 ° C. for 0.5 to 5 hours. By heat treatment, it can be converted into a polyimide film, and a metal foil-polyimide composite can be obtained.

Further, the photosensitive polyimide precursor film of the metal foil-polyimide composite can be patterned. In this case, exposure is performed using a normal photomask. The actinic rays used at this time include, for example,
Ultraviolet rays, electron beams, X-rays and the like can be mentioned, and among them, ultraviolet rays are preferable.
Low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, halogen lamps, germicidal lamps, and the like are included. Among these light sources, an ultra-high pressure mercury lamp is preferred.

After the exposure, if necessary, a heat treatment is carried out, followed by development using a developing solution to remove unexposed portions or exposed portions. In this case, an immersion method or a spray method can be used. As the developer, those similar to the organic solvent that can dissolve the polyamic acid, which is preferably used when synthesizing the polyamic acid, are usually used. In addition, water can be added to such an organic solvent in order to improve developability. When water is added, the amount is usually 1 to 100% by weight, preferably 5 to 100% by weight, based on the organic solvent.
５０50% by weight. If the amount is too large, phase separation may occur with the organic solvent. If the amount is too small, the effect of improving the developability is not exhibited. In the case of an alkaline aqueous solution, sodium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline and the like are used. Immediately after development, ethyl alcohol, isopropyl alcohol, isobutyl alcohol, hexane,
It is desirable to perform rinsing with an organic solvent such as pentane, a mixed solvent of water and an organic solvent miscible with water in an arbitrary ratio, or water alone.

The pattern of the polyimide precursor obtained by the development is thereafter converted into a polyimide pattern by heat treatment. The heat treatment is usually performed continuously or stepwise for 0.5 to 5 hours at a temperature of 150 to 450 ° C. in a nitrogen atmosphere or in a vacuum to form a patterned metal foil. A polyimide composite is obtained.

In addition, it is possible to obtain a metal foil-polyimide composite in which at least one layer composed of a thin film conductor circuit and polyimide is formed on a patterned polyimide. As a thin-film conductor circuit formed on a polyimide, C is formed by a method such as sputtering, plating, or evaporation.
u, Cr, Ti, Ni, Ag, Au, Pd, Pt, A
Metals such as l and Sn are conceivable, and these may be used alone or in the form of an alloy, or two or more metals may be formed in layers. Among these, Cr is preferable as the metal thin film that comes into direct contact with the polyimide because of its adhesion to the polyimide. After processing the formed metal thin film into a pattern using a photoresist to form a circuit, a second layer of a polyimide precursor is applied, dried, and processed into a pattern to form the metal foil-polyimide composite. Obtainable.

[0035]

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, a dry air inlet and a stirrer
1.14 g (0.006 mol) of 4,4′-diaminodiphenyl ether (DAE) in a 4-ml four-necked flask,
4,4'-diaminobenzanilide (DABA) 3.0
2 g (0.013 mol), bis-3- (aminopropyl) tetramethylsiloxane (SiDA) 0.25 g
(0.001 mol), 56.45 g of N, N'-dimethylacetamide were made to flow in a nitrogen stream and stirred at room temperature. After confirming dissolution, 1.77 g (0.03 g) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA)
06 mol), pyromellitic dianhydride (PMDA)
After adding 06 g (0.014 mol), the mixture was stirred for about 5 hours, and then heated at 65 ° C. for 1 hour.

Next, 0.09 g of Michler's ketone, 1-phenyl-propanedione-2- (o
After mixing and stirring 0.09 g of -benzoyl) oxime and 1.8 g of N, N-dimethylaminoethyl methacrylate, the mixture was filtered through a filter to obtain a photosensitive polyimide precursor composition solution.

This solution was added to a 10 μm × 10 cm square 25 μm
The mSUS foil was spin-coated and dried by heating at 90 ° C. for 80 minutes to form a film having a thickness of 20 μm. The film surface was exposed for 3 minutes using an ultra-high pressure mercury lamp with an output of 7 mW / cm ² under a nitrogen atmosphere, and then a developer DV-50 manufactured by Toray
5 for 5 minutes, and then rinsed with isopropanol for 1 minute. At this time, the thickness of the film was 19 μm. This was heat-treated in steps of 100 ° C. for 30 minutes and 350 ° C. for 60 minutes to obtain a polyimide film having a thickness of 10 μm. At this time, when the warpage of the four corners of the SUS foil coated with the polyimide was measured and averaged, it was 2.8 mm, and the warpage value was 28 × 10 ⁻³ . In addition, 3 of this polyimide film
The average coefficient of linear expansion in the range of 0 ° C to 100 ° C is 18 × 10
^-6 .

Next, in order to process the pattern, the thickness 2
Using a film of 0 μm, this film surface was subjected to pattern masking and development was carried out in the same manner to obtain a polyimide precursor pattern having a thickness of 19 μm. 100 ° C under nitrogen atmosphere
Heat treatment at 350 ° C for 60 minutes for 30 minutes,
A polyimide pattern having a thickness of 10 μm was obtained. The SUS-polyimide membrane composite formed in this pattern is 2 m wide.
m, 3 mm in length, one end in the length direction was fixed to a fixed base, and the height from the other fixed base was measured using Lasertec 1LM21. It was .0 × 10 ^-3.

Examples 2 to 5 and Comparative Examples 1 and 2 Example 1 was repeated except that the polymer composition ratio was in accordance with Table 1.
The procedure was performed in the same manner as described above. Table 1 also shows the obtained warpage value, linear expansion coefficient, and warpage coefficient.

[0041]

[Table 1] (PMDA in the table is pyromellitic dianhydride, BPDA is 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, DABA is 4,4'-diaminobenzanilide,
DAE is 4,4'-diaminodiphenyl ether, BA
POD indicates 4,4'-bis (4-aminophenoxy) biphenyl, and SiDA indicates bis-3- (aminopropyl) tetramethylsiloxane. )

Example 6 100 equipped with a thermometer, a dry air inlet and a stirrer
0.04 g (0.002 mol) of 4,4'-diaminodiphenyl ether, 4,4'-
3.86 g (0.017 mol) of diaminobenzanilide, 0.25 g (0.001 mol) of bis-3- (aminopropyl) tetramethylsiloxane, and 56.45 g of N, N'-dimethylacetamide were made to flow in nitrogen gas, and room temperature. And stir. After confirming dissolution, 3,3 ', 4,4'
1.77 g of biphenyltetracarboxylic dianhydride
(0.006 mol), pyromellitic dianhydride 3.06
g (0.014 mol), and then stirred for about 5 hours.
Thereafter, the mixture was heated at 65 ° C. for 1 hour. Next, 40
1.55 g of isocyanatoethyl methacrylate at 0.2 ° C. using 0.2 g of N, N-dimethylbenzylamine as a catalyst
(0.01 mol) was gradually added, and the mixture was stirred at 40 ° C. for 4 hours, then, Michler's ketone 0.09 g, 1-phenyl-propanedione-2- (o-benzoyl) oxime 0.09 g was added.
g was mixed and stirred, and then filtered through a filter to obtain a photosensitive polyimide precursor composition solution.

This solution was added to a 10 μm × 10 cm square 25 μm
The mSUS foil was spin-coated and dried by heating at 90 ° C. for 60 minutes to form a film having a thickness of 20 μm. The film surface is exposed for 1.5 minutes using an ultra-high pressure mercury lamp with an output of 7 mW / cm ² in a nitrogen atmosphere, and then a developing solution consisting of N, N-dimethylacetamide / methanol = 4/1 volume And rinsed with ethanol for 1 minute. At this time, the thickness of the film was 18 μm. This at 150 ° C for 30 minutes,
Heat treatment at 400 ° C for 60 minutes, thickness 10μ
m of a polyimide film was obtained. At this time, when the warpage of the four corners of the SUS foil coated with the polyimide was measured and averaged, it was 4.1 mm, and the warpage value was 41 × 10 ⁻³ . The average linear expansion coefficient of this polyimide film in the range of 30 ° C. to 100 ° C. was 21 × 10 ⁻⁶ .

Next, in order to process the pattern, the thickness 2
Using a 0 μm film, this film surface was subjected to pattern masking and developed in the same manner to obtain a polyimide precursor pattern having a thickness of 18 μm. This is placed in a nitrogen atmosphere at 150 ° C.
Heat treatment was performed for 30 minutes at 400 ° C. for 60 minutes to obtain a polyimide pattern having a thickness of 10 μm. This pattern was cut into a width of 2 mm and a length of 3 mm, and one end in the length direction was fixed to a fixed base, and the height from the other fixed base was measured using Lasertec 1LM21.
μm, and the warpage coefficient was 6.0 × 10 ⁻³ .

Example 7 500 equipped with a thermometer, a dry air inlet and a stirrer
8.83 g (0.03 g) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was placed in a separable flask having a capacity of 3 ml.
3 mol), 2-hydroxyethyl methacrylate
02 g (0.20 mol), 100 m of γ-butyrolactone
After stirring at 60 ° C. for 2 hours, 15.27 g (0.07 mol) of pyromellitic dianhydride was added under ice-cooling. Further, 17.0 g of pyridine was stirred with ice cooling.
Was added. After stirring at room temperature for 16 hours, a solution of 41.2 g (0.20 mol) of dicyclohexylcarbodiimide in 40 ml of γ-butyrolactone was added over 10 minutes under ice-cooling, followed by 4,4′-diaminobenzanilide.
30 g (0.085 mol), 2.00 g (0.01 mol) of 4,4′-bis (4-aminophenoxy) biphenyl, 1.24 g (0.005 mol) of bis-3- (aminopropyl) tetramethylsiloxane ) Was added over 15 minutes. After stirring for 3 hours under ice-cooling, 5 ml of ethanol was added and the mixture was further stirred for 1 hour. After the precipitate was filtered off, 10 L of ethanol was added to the obtained solution, and the formed precipitate was washed with ethanol and dried under vacuum. To obtain a powder. Under light blocking, 30 g of this powder, 0.6 g of Michler's ketone, 1-
After dissolving 0.6 g of phenyl-propanedione-2- (o-benzoyl) oxime in 45 g of N-methyl-2-pyrrolidone, the solution was filtered through a filter to obtain a photosensitive polyimide precursor composition solution.

This solution was added to a 10 cm × 10 cm square 25 μm
The mSUS foil was spin-coated and dried by heating at 80 ° C. for 60 minutes to form a film having a thickness of 20 μm. The film surface was exposed for 1.5 minutes using an ultra-high pressure mercury lamp having an output of 7 mW / cm ² under a nitrogen atmosphere.
After developing with a developing solution consisting of xylene = 7/3, it was rinsed with isopropanol for 1 minute. At this time, the thickness of the film was 19 μm. This is placed at 150 ° C. for 60 minutes, 35
Heat treatment at 0 ° C for 120 minutes, thickness 10μm
Was obtained. At this time, the warpage of the four corners of the SUS foil coated with the polyimide was measured and averaged to be 4.6 mm, and the warpage value was 46 × 10 ⁻³ . The average linear expansion coefficient of this polyimide film in the range of 30 ° C. to 100 ° C. was 23 × 10 ⁻⁶ .

Next, to process the pattern, the thickness 2
Using a film of 0 μm, this film surface was subjected to pattern masking and development was carried out in the same manner to obtain a polyimide precursor pattern having a thickness of 19 μm. This is placed in a nitrogen atmosphere at 150 ° C.
Heat treatment was performed at 350 ° C. for 120 minutes for 60 minutes to obtain a polyimide pattern having a thickness of 10 μm. This pattern was cut into a width of 2 mm and a length of 3 mm, and one end in the length direction was fixed to a fixed base, and the height from the other fixed base was measured using Lasertec 1LM21 to be 22 μm. The warpage coefficient was 7.3 × 10 ⁻³ .

[0048]

The object of the present invention is to provide a photosensitive polyimide precursor composition which has no problem in mechanical strength, heat resistance, flexibility and the like, and enables more favorable pattern processing. Curling does not occur in a metal-polyimide composite material made of a material, and in the semiconductor field, even if the thickness of polyimide is increased, the warpage of a silicon wafer as a substrate is suppressed.

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Claims (6)

[Claims] 1. A photosensitive polyimide precursor composition comprising (A) a polymer represented by the following general formula (1) and (B) a photopolymerization initiator, wherein the composition is cured at 30 ° C. 1
The average linear expansion coefficient at 00 ° C. is 10 × 10 ⁻⁶ / ° C. to 30 ×
A photosensitive polyimide precursor composition having a temperature of 10 ⁻⁶ / ° C. Embedded image (In the general formula (1), R ¹ is a tetravalent aromatic acid residue, and R ² is 6
0 mol% or more represents an aromatic diamine residue which is a diaminobenzanilide residue, and R ³ represents —OR ⁴ , —NHR ⁴ ,
^{O - N + R 4 R 5} R 6 group selected from R ^7, or shows a mixture of these radicals and -OH. Where R ⁴ is at least 1
Groups having ethylenically unsaturated bonds, R ⁵ ,
R ⁶ and R ⁷ each represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. n is 1 or 2. ) 2. In the general formula (1), R ³ is —O ^— N ⁺ R ⁴
A group represented by R ⁵ R ⁶ R ⁷ , or a mixture of this group and —OH, wherein R ⁴ represents a group having at least one ethylenically unsaturated bond, and R ⁵ , R ⁶ , R ⁷ The photosensitive polyimide precursor composition according to claim 1, wherein each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. 3. The compound of the formula (1) wherein R ¹ is 10 to 10
0 mol% is the residue of biphenyltetracarboxylic acid,
-90 mol% are residues of pyromellitic acids, and 60-95 mol% of R ² are diaminobenzanilide residues,
2. The photosensitive polyimide precursor composition according to claim 1, wherein 〜40 mol% is an aromatic diamine residue containing an ether bond in the molecule. 4. A cured metal foil-polyimide composite comprising applying the photosensitive polyimide precursor composition according to claim 1 on a metal foil so that the cured film has a thickness of 5 to 30 μm. The warp value of the composite after curing is 80 × 10
A metal foil-polyimide composite having a molecular weight of ^-3 or less. 5. The metal foil-polyimide composite according to claim 4, wherein the composite is formed in a pattern, and the formed metal foil-polyimide composite has a warp coefficient of 15 × 10 ⁻³ or less. The metal foil-polyimide composite characterized by the above-mentioned. 6. The metal foil according to claim 4, wherein the metal foil is a stainless steel foil having a thickness of 10 to 30 μm.
Polyimide composite.