JPH08253584A - Polyimide composition - Google Patents

Abstract

PURPOSE: To obtain a polyimide composition for electronic materials, which can give a highly functional polyimide by using a polyimide precursor made from a specified diamine and two specified acid dianhydrides as the principal components. CONSTITUTION: A polyimide composition obtained by using as the principal components a polyimide precursor made from a diamine component based on an aromatic diamine represented by the formula (wherein R is at least one member selected from the group consisting of a 1-10 C alkyl, alkoxy, acyl, chloro, bromo and fluoro; and (n) is an integer of 0-4) and an acid component comprising pyromellitic dianhydride and 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride in a molar ratio of 6/4 to 1/9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyimide composition, and more particularly to improving the properties of a polyimide composition for electronic materials.

[0002]

2. Description of the Related Art In recent years, polyimide has been used for electronic materials such as an interlayer insulating film, a passivation film and an α-ray shielding film of a semiconductor element because of its high heat resistance and excellent electrical characteristics. . In these fields, polyimide is rarely used as it is without pattern processing, and it is usually necessary to have a function of pattern processing such as opening holes for connection between conductors. In addition, there are applications that require other functions, such as low thermal expansion coefficient and high heat resistance, and the development of polyimide suitable for each application is underway.

As a polyimide having high heat resistance and low thermal expansion coefficient, for example, a polyimide composed of pyromellitic acid and paraphenylenediamine can be mentioned.
This polyimide is, for example, S.M. E. FIG. Sloog eta
1, J, Polym. Sci. 16c, 1191 (19
It is known as described in 67). This polyimide has high crystallinity and has a drawback that the film becomes brittle during film formation and a tough film cannot be obtained, and it has not yet been put to practical use.

On the other hand, a polyimide composed of 3,3 ', 4,4'-diphenylethertetracarboxylic acid and paraphenylenediamine is disclosed in, for example, N.P. A. Addorova e
tal, “Polyimides” Israel Pr
ogram for Scientific Tran
It is publicly known as described in Saction (1969), and on the other hand, a tough film can be obtained, but the pattern processability is poor. That is, it has a drawback that etching cannot be performed with an etchant using hydrazine-ethylenediamine.

Furthermore, when polyimide is used for electronic materials, it is often exposed to an alkaline aqueous solution such as sodium hydroxide when plating with a metal or developing a resist, and resistance to these chemicals is required. To be done.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and its purpose is to have high heat resistance and low thermal expansion coefficient, toughness, and pattern workability. Another object of the present invention is to provide a polyimide composition for electronic materials, which is capable of obtaining a highly functional polyimide having excellent chemical resistance.

[0007]

The object of the present invention is as follows.
General formula in the raw material diamine component

Embedded image (In the formula, R is at least one selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an acyl group, chlorine, bromine, and fluorine, and n is an integer of 0 to 4.)
The aromatic diamine represented by the following is contained as a main component, and pyromellitic dianhydride and 3,3 ′, are contained in the raw material acid component.
Achieved by a polyimide composition for electronic materials, characterized by containing as a main component a polyimide precursor containing 4,4′-diphenyl ether tetracarboxylic dianhydride in a molar ratio of 6/4 to 1/9 To be done.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The polyimide composition for electronic materials of the present invention contains a polyimide precursor composed of a specific monomer component as a main component.

The polyimide precursor is represented by the general formula

Embedded image (In the formula, R is at least one selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an acyl group, chlorine, bromine, and fluorine, and n is an integer of 0 to 4.)
It contains an aromatic diamine represented by
If the aromatic diamine is not the main component, the thermal linear expansion tends to be high and the chemical resistance tends to be poor.

The aromatic diamine represented by the general formula (1) is paraphenylenediamine and its nuclear substitution product. Preferred aromatic diamines used in the present invention include, but are not limited to, paraphenylenediamine, methyl-paraphenylenediamine, chloro-paraphenylenediamine, methoxy-paraphenylenediamine, dimethyl-paraphenylenediamine, and the like. .

The polyimide precursor contains
Pyromellitic dianhydride (hereinafter abbreviated as PMDA) and 3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride (hereinafter abbreviated as DEDA) in a molar ratio of 6/4
It is contained at a ratio of 1/9. When the molar ratio of PMDA and DEDA is more than 6/4, there is a disadvantage that after being converted into polyimide, it becomes brittle when immersed in an alkaline aqueous solution such as sodium hydroxide, which is not preferable. If the molar ratio is less than 1/9, good pattern workability cannot be obtained. A particularly preferred range is 5/5 to 3/7.

The polyimide precursor of the present invention is a blend of a polyimide precursor composed of PMDA and an aromatic diamine represented by the general formula (1) and a polyimide precursor composed of DEDA and the aromatic diamine. You can
It may be a copolymer obtained by reacting a mixture of PMDA and DEDA with the aromatic diamine.

It is also possible to introduce other aromatic diamines, aromatic tetracarboxylic acids, etc. into the polyimide precursor described above within a range that does not significantly impair its properties. Specific examples include aromatic diamines such as benzidine, diaminoterphenyl, diaminodiphenyl ether and diaminodiphenyl sulfone, and aromatic tetracarboxylic acids such as benzophenone tetracarboxylic acid and biphenyl tetracarboxylic acid. Further, in order to improve the adhesiveness, a diamine having a siloxane structure, for example, 1,3-bis (3-aminopropyl) tetramethyldisiloxane may be blended in an amount of 1 to 6 mol%.

In the polyimide composition of the present invention, other polyimide precursors may be mixed within the range in which the polyimide precursor described above is the main component.

Next, an example of the method for producing the polyimide composition of the present invention will be described. That is, PMDA and DE in the solvent
A mixture of DA in a molar ratio of 6/4 to 1/9 and the above-mentioned aromatic diamine are added in an amount of 90 to 110 mol%, more preferably equimolar to the total amount of acid anhydride, and -20 ° C to 100 ° C.
A varnish of a polyimide precursor can be obtained by reacting with. Alternatively, a varnish of a polyimide precursor can be obtained by blending a product obtained by reacting PMDA with the above-mentioned aromatic diamine under the same conditions and a product obtained by reacting DEDA with the above-mentioned aromatic diamine under the same conditions. it can. The varnish thus obtained is as it is,
Alternatively, the polyimide composition of the present invention can be obtained by diluting with a suitable solvent.

As the solvent used in the above-mentioned production method, a polar solvent is preferably used from the viewpoint of polymer solubility, and an aprotic polar solvent is particularly preferable. As the aprotic polar solvent, N-methyl-2-pyrrolidone,
N, N-dimethylformamide, N, N-dimethylacetamide, hexamethylphosphorotriamide, dimethylsulfoxide, γ-butyrolactone and the like are preferably used.

Next, the polyimide precursor is chemically or thermally treated to undergo dehydration ring closure to be converted into polyimide. When chemically treating, a polyimide precursor film is prepared and immersed in a mixed solution of acetic anhydride and pyridine to obtain a film of the polyimide composition of the present invention. In the case of thermal treatment, a polyimide precursor film is prepared and heat treated to similarly obtain the polyimide composition film of the present invention.

The heat treatment is preferably carried out for 5 minutes to 5 hours while selecting a temperature in several steps in the range of room temperature to 450 ° C. and gradually increasing the temperature, or by selecting a certain temperature range and continuously increasing the temperature. . For example, heat treatment may be performed at 130 ° C. and 200 ° C. for 30 minutes each, or the temperature may be linearly increased from room temperature to 400 ° C. over 2 hours.

When patterning is required as in the case of an interlayer insulating film of a multi-layer wiring of an LSI, a polyimide composition is applied on a substrate, and after heat treatment, a negative photoresist is used as a mask and etching is performed with a mixed solution of hydrazine and ethylenediamine. Then, the pattern can be easily formed.

The polyimide composition thus obtained has a high heat resistance, a low linear expansion property, a chemical resistance and an appropriate etching rate, and is therefore used for electronic materials. For example, it can be effectively used for the following purposes.

(1) Film carrier type IC, LSI (2) Insulation coil using heat resistant film (3) Flexible printed circuit board (4) Printed circuit board formed on metal plate (5) Solar cell (6) Organic filler (7) LSI with multi-layer wiring (8) Semiconductor device with passivation film (9) Semiconductor device with α-ray shielding film (10) Integrated circuit mounting substrate (11) Resilient magnetic head Among the above applications However, it is particularly preferably used for the applications (7) to (11).

Next, the present invention will be specifically described based on examples.

[0023]

【Example】

(Characteristic measuring method and effect evaluating method) Heat resistance A solution of a polyimide precursor is applied on a polyester film and dried at 80 ° C for 60 minutes. Then, the polyimide precursor film is peeled off from the polyester film, and after tension-fixed to an iron frame, 135 ° C, 200 ° C,
Heat treatment is performed at 300 ° C. and 400 ° C. for 30 minutes each to form a polyimide film. The thickness is adjusted to 20 ± 2μ.

Using this film, thermogravimetric analysis was carried out under the following conditions, and the thermal decomposition temperature when it was reduced by 1% was measured to obtain heat resistance.

Apparatus: Thermogravimetric analyzer TG-30M manufactured by Shimadzu Corporation Sample amount: 5 mg Temperature rising rate: 10 ° C./min Atmosphere: Nitrogen (flow rate 50 ml / min) Etching rate (pattern workability) of polyimide precursor The solution is applied on a stainless steel plate having a thickness of 50 μm so that the film thickness after imidization is 20 ± 2 μm,
Dry for 60 minutes at 80 ° C. 135 ℃, 200 ℃,
Heat treatment was performed at 300 ° C. and 400 ° C. for 30 minutes each to form a polyimide film on the stainless steel plate.

Next, this was immersed in a solution of hydrazine / ethylenediamine = 1/2 (volume ratio) at 40 ° C., and the time for removing the polyimide was measured to obtain the etching rate, which was defined as the pattern processability. .

A varnish of heat-expandable polyimide precursor was applied onto the stainless steel plate to form a polyimide film under the same conditions. These 400
It was heated on a hot plate at ℃, confirmed to be flat, cooled to room temperature, and the warpage on the stainless steel plate after cooling was observed. If the stainless steel side is curved inward, the coefficient of linear thermal expansion of this polyimide will be smaller than the coefficient of thermal linear expansion of stainless steel (1.8 × 10 ⁻⁵ ), which is indicated by a minus (−). Further, the degree of bending is displayed in five stages, with (-1) having the largest bending and (-5) having the smallest bending. Therefore, (-1) has the smallest thermal expansion coefficient.

Chemical resistance A varnish of a polyimide precursor is applied on a glass plate so that the film thickness after imidization is 20 ± 2 μm, and dried at 80 ° C. for 1 hour. The polyimide precursor film was peeled off from the glass plate and fixed to a stainless frame. This film was heat-treated at 200 ° C., 300 ° C. and 400 ° C. for 30 minutes each, cooled and then removed from the stainless frame and immersed in a 10% aqueous sodium hydroxide solution at room temperature for 5 days. After completion of the immersion, the film was washed with water and the shape of the film was visually inspected. The sample hydrolyzed by alkali becomes brittle and breaks when bent. Therefore, the test examined whether or not the alkali-treated film was bent and broken.

Examples 1 to 3, Comparative Examples 1 and 2 Paraphenylenediamine (PDA) 21.6 g (0.2
Mol) to 700 g of dimethylacetamide under a nitrogen stream,
Dissolve at room temperature. Pyromellitic anhydride (PMD
A) 43.62 g (0.2 mol) was added together with 50 g of dimethylacetamide, and the mixture was stirred for 30 minutes in an ice bath under a nitrogen stream and then reacted for 10 hours at room temperature to give a polyimide precursor having a viscosity of 100 poises. Varnish A was obtained.

21.63 g (0.2 mol) of PDA was dissolved in 600 g of dimethylacetamide at room temperature under a nitrogen stream. Here, 62.20 g (0.23 g) of 3,3 ', 4,4'-diphenyl ether carboxylic acid dianhydride (DEDA)
Mol) with 115 g of dimethylacetamide,
The mixture was stirred for 30 minutes in an ice bath under a nitrogen stream, and then reacted for 10 hours at room temperature to obtain a varnish B of polyimide precursor having a viscosity of 100 poise.

Based on the above varnishes A and B, a varnish of polyimide precursor having the composition shown in Table 1 was obtained.

Using these varnishes, a polyimide film was prepared by the above-mentioned method, and the film strength (film forming ability), etching rate, chemical resistance, heat resistance and thermal expansion coefficient were measured. Indicated.

Examples 1 to 3 are polyimide compositions comprising the polyimide precursor of the present invention, and Comparative Example 1 is the raw material acid component is P.
A polyimide composition composed only of MDA, and Comparative Example 2 is a polyimide composition composed only of a raw acid component, i.e. DEDA. Comparative Example 3 is a sample in which the ratio of PMDA is 7, which is higher than the range of the present invention.

As is clear from Table 1, the starting acid component is P
If MDA alone is used, there is no film forming ability, and if the starting acid component is only DEDA, the etching rate is extremely slow. Further, even in the case of copolymerization of PMDA and DEDA, when the amount of PMDA is too large, there is a drawback that the chemical resistance is poor.

[0035]

[Table 1] Example 4 2,5-Dimethylaminoparaphenylenediamine 13.
61 g (0.1 mol) of NMP18 at room temperature under nitrogen stream
It was dissolved in 0 g. PMDA 5.45g (0.0
25 mol), DEDA 23.27 g (0.075 mol)
Was added at once with 60 g of NMP, and the mixture was stirred for 30 minutes in an ice bath under a nitrogen stream and then reacted for 10 hours at room temperature to obtain a varnish of a polyimide precursor having a viscosity of 80 poise. Based on the above varnish, a polyimide film was prepared by the above-mentioned method, and the film strength (film forming ability), etching rate, chemical resistance, heat resistance, and thermal expansion coefficient were measured. The polyimide composition provides a tough film, and at the same time, has an etching rate of 1.3 μm / min in a preferable range, has no chemical resistance, has a thermal expansion coefficient smaller than that of stainless steel, and has a heat resistance of 490 ° C. Characterized.

Example 5 10.81 g (0.1 mol) of paraphenylenediamine was dissolved in 180 g of NMP at room temperature under a nitrogen stream. PMDA 5.45g (0.025mol), DEDA2 here
3.27 g (0.075 mol) was added at once together with 60 g of NMP, and the mixture was stirred for 30 minutes in an ice bath under a nitrogen stream and then reacted for 10 hours at room temperature to give a viscosity of 100.
A varnish of poise polyimide precursor was obtained.

Based on the above varnish, a polyimide film was prepared by the above-mentioned method, and the film strength (film forming ability), etching rate, chemical resistance, heat resistance, and thermal expansion coefficient were measured. The present polyimide composition provides a tough film, has an etching rate in a preferable range of 1.5 μm / min, has no chemical resistance, has a thermal expansion coefficient smaller than that of stainless steel, and has a heat resistance of 505 ° C. Characterized.

Comparative Example 4 4.33 g (0.04 mol) of paraphenylenediamine and 12.01 g of 4,4'-diaminodiphenyl ether.
250 g of NMP (0.06 mol) at room temperature under nitrogen flow
Dissolved in. PMDA 5.45g (0.025
23.27 g (0.075 mol) of DEDA
MP80 was added together with MPg at once, and the mixture was stirred for 30 minutes in an ice bath under a nitrogen stream and then reacted at room temperature for 10 hours to obtain a varnish of a polyimide precursor having a viscosity of 100 poise.

Based on the above varnish, a polyimide film was prepared by the method described above, and the film strength (film forming ability), etching rate, chemical resistance, heat resistance, and thermal expansion coefficient were measured. The present polyimide composition provides a tough film, and at the same time, the etching rate is in the preferable range of 1.1 μm / min, and there is no problem in chemical resistance, but since paraphenylenediamine is 40% in the diamine component, The coefficient of thermal expansion was greater than that of stainless steel. Also, heat resistance 5
It was 00 ° C.

Example 6 10.27 g (0.095 mol) of paraphenylenediamine and 1.24 g (0.005 mol) of bis (3-aminopropyl) tetramethyldisiloxane were dissolved in 180 g of NMP at room temperature under a nitrogen stream. It was PMDA5.
45 g (0.025 mol), DEDA 23.27 g
(0.075 mol) was added at once with 60 g of NMP, and the mixture was stirred in an ice bath for 30 minutes under a nitrogen stream, and then reacted at room temperature for 10 hours to obtain a varnish of a polyimide precursor having a viscosity of 90 poise.

Based on the above varnish, a polyimide film was prepared by the method described above, and the film strength (film forming ability), etching rate, chemical resistance, heat resistance, and thermal expansion coefficient were measured. The present polyimide composition provides a tough film, has an etching rate of 1.5 μm / min in a preferable range, has no chemical resistance, has a thermal expansion coefficient smaller than that of stainless steel, and has a heat resistance of 500 ° C. Characterized.

[0042]

When the polyimide composition of the present invention is used,
It is possible to obtain a highly functional polyimide having high heat resistance and low thermal expansion coefficient, being tough and having excellent pattern processability as well as excellent chemical resistance. Therefore, it can be preferably used for electronic materials.

Claims (1)

[Claims] 1. A compound represented by the general formula: (In the formula, R is at least one selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an acyl group, chlorine, bromine, and fluorine, and n is an integer of 0 to 4.)
The aromatic diamine represented by the following is contained as a main component, and pyromellitic dianhydride and 3,3 ′, are contained in the raw material acid component.
A polyimide composition for an electronic material, comprising as a main component a polyimide precursor containing 4,4'-diphenyl ether tetracarboxylic dianhydride in a molar ratio of 6/4 to 1/9.