JPS63305129A - Polyimide composition - Google Patents

Abstract

PURPOSE:To obtain the title composition which can give a polyimide low in Young's modulus and excellent in strength, elongation and moisture-resistant adhesion, by reacting a mixture of three diamines of a specified mixing ratio with pyromellitic dianhydride. CONSTITUTION:A diamine component (A) is obtained by mixing a diamine (a) of formula I (wherein X is -O- or -S-) with a diamine (b) of formula II (wherein Y is X, -SO-, -SO2-, -CO-, -CH2-, -CF2-, -CCl2- or a group of formula III or IV) in an amount to give a molar ratio (b/a) of 5-95/95-5 and a diamine (c) of formula V (wherein R is a 1-20C alkylene, a fluoroalkylene or phenylene, R' is a 1-10C alkyl, fluoroalkyl or phenyl and n is 3-20) in an amount to give a molar ratio of c to (a+b+c) of 5/1,000-10/100. Component A is reacted with 90-110mol.%, based on component A, pyrmellitic dianhydride (B) at -20-100 deg.C to obtain the title composition as a varnish of a polyimide precursor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polyimide composition, and more particularly to a polyimide composition capable of obtaining a polyimide having a low Young's modulus.

[Background Art] In recent years, in the semiconductor industry, the integration of semiconductor elements has progressed rapidly, and in the field of DRAM, products of 4 Mbit level are being prototyped. However, with this increase in integration, the problem of thermal stress caused by the difference in linear expansion coefficient between the silicon substrate and the resin encapsulant becomes greater, leading to problems such as cracks in the passivation film and breakage of aluminum wiring. A situation is occurring. Unless these problems are resolved, products with stable quality cannot be obtained. Therefore, it is desired to develop a heat-resistant resin coating agent with a low Young's modulus in order to weaken thermal stress, but in the case of conventional polyimide, the Young's modulus is at least 250 kQ/mm2. .

In view of these circumstances, the inventors of the present invention have conducted extensive studies on measures to reduce the Young's modulus of polyimide, and have developed a polyimide composition composed of a combination of siloxane diamine with a specific structure, aromatic diamine, and acid anhydride. The inventors have discovered that, in this case, a polyimide having a significantly low Young's modulus and excellent strength and elongation properties and moisture-resistant adhesive properties can be obtained, and the present invention has been achieved based on this finding.

[Problems to be Solved by the Invention] Therefore, an object of the present invention is to provide a polyimide composition that has a low Young's modulus and is excellent in strength, elongation, and moisture-resistant adhesive properties.

[Means for Solving the Problems] The object of the present invention is to solve the following formulas (I), (II> and (
The molar ratio of the diamine component represented by II[> is (I)+(II)+(I[I) 1000 10
This is achieved by a polyimide composition obtained by reacting a compound blended to give 0(I) 95 5 and pyromellitic dianhydride.

(n) (wherein, X is 10- or -5-1Y is 10-1-S-
1-SO-1-502-1-CO-1-CH2-1-C
F2-1-COD, 2-1 alkylene group, fluorinated alkylene group or phenylene group, R' has 1 to 10 carbon atoms
an alkyl group, a fluorinated alkyl group or a phenyl group,
n is an integer from 3 to 20. ) The diamine component used in the present invention has the above formula (I),
It has a structure represented by (I[) and (I[I), where X is selected from 10- or -S-. Y is 10-
1-S-1-8O-1-502-1-CO-1-CH2
-1-CF2-1-C (42 preferably 10-1-8-
or 10F2-, but is not limited thereto. R represents an alkylene group, a fluorinated alkylene group, or a phenylene group having carbon r111 to r20, and more preferably a methylene group, a propylene group, a hexafluoropropylene group, and a phenylene group. R' represents an alkyl group having 1 to 10 carbon atoms, a fluorinated alkyl group, or a phenyl group, more preferably a methyl group, a trifluoromethyl group, or a phenyl group. n is an integer of 3 to 20, more preferably an integer of 8 to 14.

The polyimide composition in the present invention contains the three types of diamine components described above in a molar ratio of (I>+ (If) + (I[[) 1000
100(I) 95 5 and is obtained by reacting this blend with pyromellitic dianhydride.

Here, (In>/((I)+ (II)+ (III
) When ) is less than 5/1000, a product with a low Young's modulus cannot be obtained, and when it is more than 10/100, a transparent product cannot be obtained and practicality is lost. Also (n)/(1
) is more than 9515, the varnish becomes unstable and tends to gel, thus losing its practicality. More preferably, (I) + (n) + (III) 1000 100 (
n) in the range of 20 80 .

The polyimide composition of the present invention can be modified with other diamines or tetracarboxylic acids as long as the Young's modulus is not affected. Examples of such diamines include phenylene diamine, toluenediamine, 3,3'-diaminodiphenylsulfone, benzizine, 3,4''-diaminodiphenylmethane, dimethylbenzidine, chlorbenzidine, diaminoterphenyl, bis(aminophenoxy ) benzene, aromatic diamines such as diaminoanthraquinone, aliphatic diamines such as ethylenediamine, diaminopropane, hexamethylenediamine, heptamethylenediamine. Examples of tetracarboxylic acids include benzophenonetetracarboxylic acid, biphenyltetra Examples include carboxylic acids, aromatic tetracarboxylic acids such as diphenyl ether tetracarboxylic acid, and aliphatic tetracarboxylic acids such as butanetetracarboxylic acid and cyclopentanetetracarboxylic acid.

In order to improve the adhesive properties, siloxane diamine such as 1,3-bis(3-aminopropyl)tetramethyldisiloxane is blended in an amount of 1 to 6 mol% based on the total amine base.
It can also be denatured.

Next, an example of a method for manufacturing the polyimide composition of the present invention will be explained. That is, three types of diamine (I) in the solvent
, (II) and (III) in molar ratio, (I>+ (
II) Ten (III) 1000 100 (II)
5 95(I) 95
5, and react this with preferably 90 to 110 mol%, more preferably equimolar pyromellitic dianhydride based on the total amount of diamine at -20°C to 100°C. , a varnish of the polyimide precursor of the present invention can be obtained.

As the solvent used in the above production method, it is preferable to use a polar solvent from the viewpoint of solubility of the polymer, and an aprotic polar solvent is particularly preferable. Examples of the aprotic polar solvent include N-methyl-2-pyrrolidone, N,N-dimethylformamide, and N.

N-dimethylacetamide, hexamethylphosphorotriamide, dimethyl sulfoxide, γ-butyrolactone,
Sulfolane and the like are preferably used.

Further, an aromatic hydrocarbon such as toluene or xylene may be mixed with the above-mentioned polar solvent.

Next, the polyimide precursor glue varnish obtained as described above is applied onto a suitable support and dried at 50 to 100°C.
A film of polyimide precursor is obtained.

A polyimide film can be obtained by chemically or thermally treating the film of the polyimide precursor thus obtained to cause dehydration and ring closure.

In the case of chemical treatment, a polyimide film is obtained by immersing a polyimide precursor film in a mixed solution of acetic anhydride and pyridine. In addition, in the case of thermal treatment, the film of polyimide precursor is
Select several temperatures within the 0°C range and increase the temperature in stages, or
It is preferable to select a certain temperature range and carry out the process for 5 minutes to 5 hours while continuously increasing the temperature. For example, 130℃, 200℃, 3
The heat treatment may be performed at 00°C and 400°C for 30 minutes each, or the temperature may be increased linearly from room temperature to 400°C over 2 hours.

(Method of Measuring Properties) ■Young's Modulus The method of measuring Young's modulus of the present invention is based on JIS-Z1702, and a test piece with a sample width of 10 mm and a test length of 5 Q mm is measured at a tensile speed of 20 mm/min using a Tensilon manufactured by Toyo Baldwin. did.

At the same time, strength and elongation were calculated.

■ Moisture-resistant adhesive In the polyimide film formed on the silicon wafer, use a cutter to make 6 cuts vertically and horizontally at 2 mm intervals to create 25 base holes. This is subjected to moist heat treatment at 120° C. under saturated steam at 2.0 atm for a predetermined period of time. Attach cellophane adhesive tape (manufactured by Chiban Co., Ltd.) to this sample,
Peel off according to the method described in JIS D0202 Table 13.1.

[Example] The present invention will be specifically described below based on examples.

Examples 1 to 3, Comparative Examples 1 to 3 Acid anhydrides and diamines listed in Table 1 were placed in a four-bottle flask equipped with a thermometer, a stirrer, and a nitrogen inlet, and N-methyl-2-pyrrolidone (hereinafter NMP) was added. The reaction was carried out in a mixed solvent of 6:4 (weight ratio) and xylene so that the solid content was 20%. The reaction was carried out in a water bath for the first 30 minutes and then at room temperature for about 5 hours to obtain polyimide precursor varnishes having the compositions shown in Table 1. Further, if the viscosity increased significantly after the reaction was completed, it was diluted with NMP as appropriate.

The obtained varnish was applied onto a silicon wafer using a spinner so that the thickness of imidization was 20μ±2μ. 80℃, 200'C1300℃, 350
Polyimide films were obtained by heat treatment at ℃ for 30 minutes each, and Young's modulus was measured.

As is clear from Table 1, the film made of the polyimide composition that satisfies the present invention has a low Young's modulus and
It can be seen that the moisture resistant adhesion and strength and elongation properties are good. On the other hand, in the case of the films made of the polyimide compositions of Comparative Examples 1 and 2 that do not contain the diamine component (III), there is no decrease in Young's modulus, and there is a drawback that the moisture-resistant adhesiveness is significantly inferior. In the case of Comparative Example 3, which does not contain the diamine component (n), the devitrification of the film is significant and the film is impractical.

Example 4 In a four-piece flask similar to Example 1, 52.5 g of 4,4-bisaminophenoxydiphenyl, 66.6Q of 4,4-diaminodiphenyl ether, and 4.0 g of 1,3-bisaminopropyltetramethyldisiloxane were added. 970 and (
(2) where R = +CH2, R- = -CH3, and silicone diamine with an amide valence of 620, 6.29, is converted into pyromellitic dianhydride, 109. 'IQ and N-methyl-
The reaction was carried out in a solvent containing 2-pyrrolidone and xylene in a weight ratio of 6/4 (solid content concentration 16%).

The reaction was carried out in a water bath for the first 30 minutes and then at room temperature for about 5 hours.

1q of the varnish was applied onto a silicon wafer using a spinner so that the thickness after imidization was 20μ±2μ. This was heat-treated at 80°C, 200°C, 300°C, and 350°C for 30 minutes each to obtain a polyimide film.
Young's modulus was measured.

This film exhibited good properties such as a Young's modulus of 160 kg/mm 2 , a moisture resistant adhesion of 250 hours, a strength of 12 kg/mm 2 , and an elongation of 30%.

[Effects of the Invention] Since the polyimide composition of the present invention is composed of the three specific diamines as described above, it is possible to obtain a highly functional polyimide with a low Young's modulus and excellent moisture-resistant adhesion, strength, and elongation. This is what was created.

Claims (1)

[Claims] Diamine components represented by the following formulas (I), (II) and (III) are combined in a molar ratio of (III)/{(I)+(II)+(III)}=5/100.
0~10/100(II)/(I)=5/95~95/
5. A polyimide composition obtained by reacting a compound blended as follows with pyromellitic dianhydride. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(III) (In the formula, X is -O- or - S-, Y is -O-, -S-
, -SO-, -SO_2-, -CO-, -CH_2-,
-CF_2-, -CCl_2-, ▲There are mathematical formulas, chemical formulas, tables, etc.▼or▲There are mathematical formulas, chemical formulas, tables, etc.▼
, R is an alkylene group having 1 to 20 carbon atoms, a fluorinated alkylene group or a phenylene group, R' is an alkyl group having 1 to 10 carbon atoms, a fluorinated alkyl group or a phenyl group, and n is an integer of 3 to 20. )