JPH05214101A - Thermoplastic polyester-imide and electronic part and device using the same - Google Patents

Abstract

PURPOSE:To obtain the subject polyester-imide which is a polymer of a specific tetracarboxylic acid anhydride and a diamine, excellent in low temperature curability, etching properties and heat resistance and useful as electronic parts, etc. CONSTITUTION:The objective polyester-imide is a polymer of (A) a tetracarboxylic acid of formula I [Y is formula II (R1 is 7-18C alkyl; R3 is 1-18C alkyl), etc.; X is 1-4C alkyl; (a) to (d) are 0-2] such as 2,2-bis[4-(3,4- dicarboxybenzoyloxy)phenyl]nonane and (B) a diamine of formula III (Z is 0, CO, C02, etc.; X' is halogen or 1-4C alkyl) such as 2,2-bis[4-(p-aminophenoxy) phenyl]ether.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel thermoplastic polyesterimide and electronic parts and electronic devices using the same.

[0002]

2. Description of the Related Art Conventionally, polyimide having excellent heat resistance obtained by polycondensation of tetracarboxylic dianhydride and diamine has been used for various electronic devices and insulating layers, buffer coat films and the like of the parts.

Further, as an alignment film of a liquid crystal display device, for example, polyimide of pyromellitic dianhydride and 4,4'-diaminodiphenyl ether condensation (Japanese Patent Publication No. 55-101).
In view of the requirement for transparency of a display element such as a film or a high pretilt angle of liquid crystal, a polyimide for this purpose has been proposed (Japanese Patent Laid-Open No. 63-259515).
JP-A-64-25126, JP-A-62-26282
9, JP-A-64-25127, JP-A-62-12782
7, JP-A-62-174725, JP-A-2-21032
8 publication). Similarly, various polyimides have been proposed for insulating films for multi-layer wiring of semiconductor devices, etc.
-8469, JP-A-50-6279).

[0004]

The curing of a polyimide film (imidization ratio of 90% or more) is usually carried out at a high temperature (250 ° C.).
Above), heating for a long time (30 minutes or more) is required. Further, since the polyimide after curing is generally infusible and insoluble,
The film once formed is not easy to etch using an alkaline solution or the like. However, for the insulation of various electronic devices in recent years, a polyimide that is hardened at a low temperature in a short time and easy to etch is required.

For example, in a liquid crystal display device, as the display element has a large screen and has a high density, the substrate of the element is also increased in size and is required to have a high precision, so that it is more and more expensive. When a polyimide film has been used as a color filter or an overcoat film for the substrate, it cannot be easily peeled off even if a defect occurs in the film, and thus the ease of reusing the substrate is important. It is becoming an issue. In addition, in the field of semiconductor devices, etc., with the miniaturization of wiring, stress migration of wiring due to high temperature curing of polyimide used as an insulating layer (cracks and disconnection due to thermal stress caused by the difference in thermal expansion coefficient of materials) occurs. Is a problem.

An object of the present invention is to provide a novel thermoplastic polyesterimide which can be cured at a low temperature (220 ° C. or lower) for a short time (10 minutes or less) and is easily etched.

Another object of the present invention is to provide an electronic component and an electronic device using the polyesterimide.

[0008]

As a result of intensive studies, the present inventors have found that bis [4- (dicarboxybenzoyloxy)]
The inventors have found that the above problem can be solved by introducing a flexible chain composed of a specific alkyl group into the central connecting group of a [phenyl] type tetracarboxylic acid, and have reached the present invention. The gist of the present invention is as follows.

(1) General formula [1]

[0010]

[Chemical 3]

(Wherein R ₁ is a C 7-18, R ₂ is a C 5-18 alkyl group, R ₃ and R ₄ are C 1-18 alkyl groups, and R ₅ and R ₆ are hydrogen or An alkyl group having 1 to 18 carbon atoms), X is an alkyl group having 1 to 4 carbon atoms,
a, b, c and d represent an integer of 0, 1 or 2 and may be the same. ] A thermoplastic polyesterimide which is a polymer of a composition of tetracarboxylic acid and diamine represented by

(2) Further, the diamine is represented by the general formula [2]

[0013]

[Chemical 4]

(Wherein R ₁ and R ₂ are alkyl groups and perfluoroalkyl groups), X ′ is a halogen atom and an alkyl group having 1 to 4 carbon atoms, and a, b, c and d are 0, 1 Or, it represents an integer of 2 and these may be the same. ] The thermoplastic polyesterimide according to (1) above, which is a diamine represented by

(3) The tetracarboxylic acid contains 5 to 95 mol of the tetracarboxylic acid represented by the general formula [1] and 95 to 9 mol of another tetracarboxylic acid. Also,
The diamine is a diamine 5-9 represented by the general formula [2].
It contains 5 mol and 95 to 5 mol of another diamine.

By using the above polymer for an alignment film of various electronic devices such as a liquid crystal display device, a color filter or an overcoat film having low heat resistance can be used, and in terms of characteristics, uneven brightness can be obtained. Be improved. Furthermore, the regeneration and etching of the substrate can be significantly facilitated.

Even when it is used for an insulating film of a semiconductor device, since the curing temperature is low and the thermal stress applied to the aluminum wiring layer is small, the occurrence of stress migration can be suppressed.

In order to increase the pretilt angle of liquid crystal molecules by using the above polymer as an alignment film for a liquid crystal display device, a tetracarboxylic acid represented by the above general formula [1] in which R ₁ has 7 or more carbon atoms is used. It is desirable to use.

Bis [4-] represented by the general formula [1]
Examples of the (dicarboxybenzoyloxy) phenyl] -type tetracarboxylic acid include 2,2-bis [4- (3,4-
Dicarboxybenzoyloxy) phenyl] nonane,
2,2-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] decane, 2,2-bis [4- (3
4-dicarboxybenzoyloxy) phenyl] tridecane, 2,2-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] tetradecane, 2,2-bis [4- (3,4-dicarboxybenzoyloxy) ) Phenyl] pentadecane, 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] -2-methyldecane, 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] -2-methyloctane,
1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] -2-ethylpentadecane, 2,2
-Bis [3,5-dimethyl-4- (3,4-dicarboxybenzoyloxy) phenyl] dodecane, 2,2-bis [3,5-dimethyl-4- (3,4-dicarboxybenzoyloxy) phenyl ] Decane, 2,2-bis [3,5-dimethyl-4- (3,4-dicarboxybenzoyloxy) phenyl] tridecane, 2,2-bis [3,5-diethyl-4- (3,4-) Dicarboxybenzoyloxy) phenyl] pentadecane, 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] cyclohexane, 1,1-bis [4- (3,4-
There are dianhydrides or carboxylic acids such as dicarboxybenzoyloxy) phenyl] propylcyclohexane and 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] heptylcyclohexane. These are preferably used by blending in a tetracarboxylic acid other than the above bis [4- (dicarboxybenzoyloxy) phenyl] type in a molar ratio of 5 to 95. If it exceeds 95 mol, there is a problem that the degree of polymerization is difficult to increase.

Examples of tetracarboxylic dianhydrides other than the bis [4- (dicarboxybenzoyloxy) phenyl] type are pyromellitic acid, methylpyromellitic acid, dimethylpyromellitic acid, and di (trifluoromethyl) pyromellitic acid. Acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 5,5'-dimethyl-3,3', 4,4'-
Biphenyl tetracarboxylic acid, p- (3,4-dicarboxyphenyl) benzene, 2,3,3 ', 4'-tetracarboxydiphenyl, 3,3', 4,4'-tetracarboxydiphenyl ether, 2,3,3 3 ', 4'-tetracarboxydiphenyl ether, 3,3', 4
4'-tetracarboxybenzophenone, 2,3
3 ', 4'-tetracarboxybenzophenone, 2,
3,6,7-tetracarboxynaphthalene, 1,4
5,7-tetracarboxynaphthalene, 1,2,5,6
-Tetracarboxynaphthalene, 3,3 ', 4,4'-
Tetracarboxydiphenylmethane, 2,3,3 ',
4'-tetracarboxydiphenylmethane, 2,2-bis (3,4-dicarboxyphenyl) propane, 2,2
-Bis [4- (3,4-dicarboxyphenoxy) phenyl] tridecane, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, 3,3 ', 4
4'-tetracarboxydiphenyl sulfone, 3,4
A dianhydride or carvone such as 9,10-tetracarboxyperylene, butanetetracarboxylic acid, 3,3 ', 4,4'-ethyleneglycolbis (phenyl) tetracarboxylic acid, cyclobutanetetracarboxylic acid, cyclopentanetetracarboxylic acid. Acid etc.

On the other hand, specific examples of the diamine represented by the general formula [2] include 2,2-bis [4- (p-aminophenoxy) phenyl] ether and 2,2-bis [4-
(P-Aminophenoxy) phenyl] ketone, 2,2-
Bis [4- (p-aminophenoxy) phenyl] ester, 2,2-bis [4- (p-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (m-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (p
-Aminophenoxy)] biphenyl, 2,2-bis [4
-(P-aminophenoxy) phenyl] propane, 2,
2-bis [4- (p-aminophenoxy) phenyl] pentane, 2,2-bis [4- (p-aminophenoxy)
Phenyl] octane, 2,2-bis [4- (p-aminophenoxy) phenyl] tridecane, 1,1,1,3
3,3-hexafluoro-2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1,1,
3,3,3-hexafluoro-2,2-bis [3,5-
Dimethyl-4- (4-aminophenoxy) phenyl] propane, 1,1,1,3,3,3-hexafluoro-
2,2-bis [3,5-dibromo-4 (4-aminophenoxy) phenyl] propane, 1,1,1,2,2
4,4,5,5,5-decafluoro-3,3-bis [4
-(4-aminophenoxy) phenyl] pentane, 1,
1,1,3,3,4,4,4-octafluoro-2,2
-Bis (4-aminophenyl) butane and the like.

Specific examples of diamines other than those mentioned above include p-phenylenediamine, m-phenylenediamine, diaminodiphenyl ether, diaminodiphenylmethane, 2,2-diaminodiphenylpropane, diaminodiphenylsulfone, diaminobenzophenone, diaminonaphthalene, diaminotadiene. -Aromatic diamines such as phenyl and 1,4-bis (4-aminophenoxy) benzene, alicyclic diamines such as diaminodicyclohexyl ether and diaminocyclohexane, fats such as 1,6-diaminohexane and 1,8-diaminooctane Group diamines, diaminosiloxanes, diaminosilanes and the like.

In the present invention, the method for synthesizing the precursor varnish is generally N-methyl-2-pyrrolidone (hereinafter referred to as NMP).
In a solvent such as dimethylformamide, dimethylacetamide, dimethylsulfoxide, dimethyl sulfate, sulfolane, butyl lactone, cresol, phenol, halogenated phenol, cyclohexanone, dioxane, tetrahydrofuran, acetophenone,
It can be carried out at 20 to + 200 ° C.

The precursor varnish may be a polyamic acid or a derivative thereof other than a complete polyamic acid, and may be one that has undergone imidization to some extent. Also, silane coupling agents, titanate coupling agents, aluminum alcoholates,
Surface treatment agents such as aluminum chelate, zirconium chelate and aluminum acetylacetone can be mixed and reacted in the precursor varnish.

In order to adjust the fluidity of the precursor varnish, the thermal expansion coefficient of the cured product, the elastic modulus, the dielectric constant, the refractive index, etc.,
Inorganic or organic powders, fibers and the like may be mixed and used as long as the object of the present invention is not lost.

The polyesterimide precursor film is formed by
It can be performed by general spin coating or printing.

The tetracarboxylic acid of the general formula [1] is
It can be applied to various fields such as ordinary epoxy resin curing agents, plasticizers, polyamide resins, polyester resins, and photosensitive resins.

[0028]

The thermoplastic polyesterimide of the present invention is more flexible than conventional polyimides because both tetracarboxylic acid and diamine have a bis [4- (dicarboxybenzoyloxy) phenyl] type basic skeleton. Has a conformation. Further, by introducing a long-chain alkyl group also in the direction of the minor axis of the central bonding group Y of tetracarboxylic acid, the flexible property of the polymer is further enhanced, and the glass transition temperature is lowered, so that low temperature curing is performed. It is thought that it has excellent properties and etching properties.

[0029]

EXAMPLES The present invention will be specifically described below based on examples.

Example 1 Synthesized 2,2-bis [4]
-(3,4-Dicarboxybenzoyloxy) phenyl] tridecane dianhydride 0.2 mol%, pyromellitic dianhydride 0.8 mol%, 1,6-hexamethylenediamine 0.8 mol% And 2,2-bis [4- (p-
0.2 mol% of aminophenoxy) phenyl] propane
Was reacted in NMP at 5 ° C. for 10 hours to prepare a polyesterimide precursor varnish. The reduced viscosity ηsp / c of the obtained precursor varnish was 0.35 dl / g (0.5% by weight, N
MP solution, 25 ° C).

The above 2,2-bis [4- (3,4-
The IR spectrum of dicarboxybenzoyloxy) phenyl] tridecane dianhydride is shown in FIG. 2920 cm
~ ^1, 2840cm ~ absorption based on the alkyl group in ^{1, also, 1730cm ~ 1, 1780cm ~ 1} , 1850cm ~ 1
The absorption based on the carbonyl group is observed.

After diluting the above polyesterimide precursor varnish to a concentration of 5% by weight, SiO ₂ -T was formed on the transparent electrode of the substrate.
Spin coating on the surface of the io ₂ inorganic film formed, 220
A polyester imide film of 500 Å was formed by heat treatment at ℃ for 10 minutes. In order to set the twist angle of the liquid crystal molecules held by the substrates to 260 degrees, the upper and lower substrates were rubbed at predetermined angles, and a spacer was sandwiched between the substrates to assemble a liquid crystal cell with a substrate gap of 6.5 μm. .. A nematic liquid crystal containing a biphenyl liquid crystal, a phenylcyclohexane liquid crystal, an ester cyclohexane liquid crystal, or a phenylcyclohexane methyl ether liquid crystal as a main component, and a liquid crystal in which 0.5% by weight of an optical rotatory substance (S811 manufactured by Merck) was added to the cell. The material was vacuum sealed.

When the frequency change (30 Hz / 500 Hz) of the threshold voltage of the liquid crystal cell was measured, it showed a value of 0.99, and the uneven brightness was reduced. A substrate having a defective polyesterimide film was regenerated by etching the substrate in an alkaline solution for 5 minutes to remove the polyesterimide film.

Example 2 Synthesized 1,1-bis [4
0.8 mol% of-(3,4-dicarboxybenzoyloxy) phenyl] cyclohexane dianhydride, 0.2 mol% of pyromellitic dianhydride and 0.8 mol% of 1,8-diaminohexane. Polyester was prepared by reacting 0.2 mol% of 1,1,1,3,3,3-hexafluoro-2,2-bis [4- (4-aminophenoxy) phenyl] propane in dimethylacetamide at 20 ° C. for 15 hours. An imide precursor varnish was created. The reduced viscosity ηsp / c of the obtained precursor varnish was 0.33 dl / g (0.5% by weight, NMP
Solution, 25 ° C).

The above 1,1-bis [4- (3,4
The IR spectrum of -dicarboxybenzoyloxy) phenyl] cyclohexane dianhydride is shown in FIG. 293
0 cm ~ ^1, 2850 cm ~ absorption based on the alkyl group in ^1, also, 1730 cm ~ ^1, 1780 cm ~ ^1, 1860
Absorption due to the carbonyl group is observed at cm- ¹ .

After the polyesterimide precursor varnish was diluted to a concentration of 3% by weight, the solution was spin-coated on the indium oxide transparent electrode 4 of the color liquid crystal display device shown in FIG. 3 and heat-treated at 200 ° C. for 10 minutes. , 400Å of polyester imide film 5 was formed. Then, in order to set the twist angle of the liquid crystal molecules to 240 degrees, the upper and lower substrates 1 were rubbed at predetermined angles, and spacers were sandwiched between the substrates to assemble a liquid crystal cell having a gap of 7.0 μm. The same liquid crystal material as in Example 1 was vacuum sealed in the cell.

Even if a dye color filter having a low heat resistance is used, the baking temperature of the varnish is as low as 200 ° C., so that the filter does not deteriorate and discolor, and the cell characteristics have a frequency change of the threshold voltage (30 Hz). / 500H
z) showed a value of 0.99, and it was possible to reduce uneven brightness. The substrate having a defective polyesterimide film was removed by etching in an alkaline solution for 5 minutes to remove the polyesterimide film and regenerate the substrate.

Example 3 The synthesized 2,2-bis [3,5-dimethyl-4- (3,4-dicarboxybenzoyloxy) phenyl] dodecane dianhydride was added in an amount of 0.7 mol% and 2,2 -Bis (3,4-dicarboxyphenyl)
0.3 mol% of hexafluoropropane dianhydride, 0.7 mol% of 2,2-bis [4- (4-p-aminophenoxy) phenyl] propane and 0.3 mol% of diaminosiloxane were added to dimethylacetamide. At 50 ℃, 12
The reaction was carried out for a time to prepare a polyesterimide precursor varnish. The reduced viscosity ηsp / c of the obtained precursor varnish is 0.
It was 35 dl / g (0.5 wt%, NMP solution, 25 ° C.).

The above-mentioned 2,2-bis [3,5-dimethyl-4- (3,4-dicarboxybenzoyloxy)]
The IR spectrum of phenyl] dodecane dianhydride is shown in FIG. 2950cm ~ ¹ , 2930cm ~ ¹ , 2850cm
~ ¹ absorption due to alkyl groups, also 1730cm
Absorption based on a carbonyl group is observed at ~ ¹ , 1780 cm ~ ¹ , 1850 cm ~ ¹ .

The polyesterimide precursor varnish was diluted to a concentration of 3% by weight, spin-coated as an overcoat film for a color filter, and heat-treated at 210 ° C. for 10 minutes. Further, the solution is further spin-coated on the transparent electrode,
Similarly, heat treatment was performed to form a polyesterimide film.

In order to set the twist angle of the liquid crystal molecules to 240 degrees, the upper and lower substrates were rubbed at predetermined angles, and spacers were sandwiched between the substrates to assemble a liquid crystal cell having a gap of 6.0 μm. The same liquid crystal material as in Example 1 was vacuum sealed in the cell.

The flatness of the color filter as an overcoat film is excellent, the color filter is not deteriorated and discolored, and the cell characteristic is a frequency change of the threshold voltage (30 Hz /
(500 Hz) showed a value of 0.99, and it was possible to reduce uneven brightness. The substrate with the defective polyesterimide film could be removed and regenerated by etching in alkali for about 5 minutes.

Example 4 Synthesized 1,1-bis [4
0.7 mol% of-(3,4-dicarboxybenzoyloxy) phenyl] -2-methyloctane dianhydride, 0.3 mol% of cyclobutanetetracarboxylic acid and 2,2
0.5 mol% of bis [4- (p-aminophenoxy) phenyl] ketone and 0.5 mol% of 1,8-diaminooctane were reacted in NMP at 120 ° C. for 6 hours to give a polyester etherimide precursor varnish. Created. The reduced viscosity ηsp / c of the obtained precursor varnish was 0.25 dl / g (0.
5% by weight, NMP solution, 25 ° C.).

The above 1,1-bis [4- (3,4-
The IR spectrum of dicarboxybenzoyloxy) phenyl] -2-methyloctane dianhydride is shown in FIG. Two
Absorption based on alkyl groups at 960 cm- ¹ and 2870 cm- ¹ and also at 1730 cm- ¹ and 1780 cm- ¹ and 186
Absorption due to a carbonyl group is observed at 0 cm to ¹ .

After diluting the above polyesterimide precursor varnish to a concentration of 5% by weight, the solution is spin-coated on the active matrix type electrode and the color filter, and 2
Heat treatment was performed at 20 ° C. for 10 minutes to form a 1000 Å polyesterimide film. Then, rubbing was performed at a twist angle of 90 degrees or less of the liquid crystal molecules, and a spacer was sandwiched between the substrates to assemble a liquid crystal cell having a gap of 7.5 μm. The same liquid crystal material as in Example 1 was vacuum sealed in the cell.

Even if a color filter having low heat resistance is used, deterioration and discoloration do not occur due to baking of the varnish, and
The substrate with a defective polyesterimide film was removed by etching in alkali. It should be noted that removal of the defective polyesterimide film is sufficient by immersing in an alkaline solution for about 10 minutes.

Example 5 Synthesized 1,1-bis [4
0.5 mol% of-(3,4-dicarboxybenzoyloxy) phenyl] propylcyclohexane dianhydride,
0.5 mol% of pyromellitic dianhydride and 0.5 mol% of 2,2-bis [4- (p-aminophenoxy) phenyl] octane, 2,2-bis [4- (p-aminophenoxy) ) Phenyl] propane 0.5 mol% in dimethylacetamide and dimethylformamide at -10 ° C, 15
The reaction was carried out for a time to prepare a polyester precursor varnish. The reduced viscosity ηsp / c of the obtained precursor varnish is 0.41d.
It was 1 / g (0.5% by weight, NMP solution, 25 ° C.).

The above 1,1-bis [4- (3,4-
The IR spectrum of dicarboxybenzoyloxy) phenyl] propylcyclohexane dianhydride is shown in FIG.
Absorption based on alkyl groups at 2930 cm- ¹ and 2850 cm- ¹ and also at 1730 cm- ¹ and 1780 cm- ¹ and 18
Absorption due to a carbonyl group is observed at 50 cm ~ ¹ .

After diluting the polyesterimide precursor varnish to a concentration of 5% by weight, the solution is coated on an SiO ₂ inorganic film formed on a transparent electrode by an offset printing machine, and 220
A 600 Å polyester imide film was formed by heat treatment at ℃ for 5 minutes. Then, in order to set the twist angle of the liquid crystal molecules to 240 degrees, the upper and lower substrates were rubbed at respective angles, and a spacer was sandwiched between the substrates to assemble a liquid crystal cell having a gap of 6.2 μm. The same liquid crystal material as in Example 1 was vacuum sealed in the cell.

Frequency change of threshold voltage (30 Hz / 5
(00 Hz) indicates 0.99, and it was possible to reduce uneven brightness. Furthermore, a phase plate was attached to provide a monochrome display liquid crystal display device. It should be noted that removal of the defective polyesterimide film is sufficient by soaking for about 5 minutes.

[Embodiment 6] In each of the above embodiments, the case where the invention is applied to a liquid crystal display device has been described, but a specific example when applied to various electronic devices will be described with reference to the drawings.

FIG. 7 is a schematic sectional view of an LSI having a multilayer wiring structure. A SiO ₂ insulating film 8 is provided on the surface of the semiconductor element 7 to form a metal film, and an unnecessary portion of the metal film is removed by an etching method to provide a first wiring 9 having a desired wiring pattern. The wiring 9 is electrically connected to the semiconductor element 7 through a through hole provided in a predetermined portion of the SiO ₂ film 8. Next, the polyester imide precursor varnish used in Example 1 was spin-coated at a final temperature of 2
After forming the polyester imide film 10 at 20 ° C., a circuit was formed by electrically connecting the second wiring 9 ′ made of a metal film and the first wiring 9 to obtain an LSI. Also,
The LSI was provided with a protective layer of epoxy resin 11 on its surface.

The above LSI has a polyester imide film 10
Since the curing temperature is low at 220 ° C., the thermal stress applied to the metal (aluminum) wiring layer is small, so that stress migration is less likely to occur.

FIG. 8 is a schematic sectional view of a semiconductor memory device having an α-ray shielding layer. A memory element 13 made of a silicon chip is fixed on the substrate 12, and the memory element 13 is electrically connected to the outside by a bonding wire 14. The surface of the memory element 13 was spin-coated with the polyesterimide precursor varnish of Example 2 and 2
It was cured at 20 ° C. to form α-ray shielding layer 15. Occurrence of stress migration was not observed.

FIG. 9 is a schematic sectional view of a thin film magnetic head. The lower alumina 17, the lower magnetic body 18, and the gap alumina 19 are formed on the substrate 16, and the conductor coil 20 is spin-coated with the polyesterimide precursor varnish of the above-mentioned Example 3 and cured at 220 ° C. for interlayer insulation. Insulated with membrane 21. A magnetic material 18 'is provided on the upper part of the structure. The conductor coil 20 formed by curing the polyesterimide
A thin-film magnetic head having an interlayer insulating film 21 having excellent flatness was obtained without any deterioration.

FIG. 10 is a schematic sectional view of a magnetic bubble memory device. The conductor 25 is provided on the garnet substrate 22, and the polyesterimide precursor varnish of Example 4 is spin-coated on the conductor 25 and cured at 200 ° C. to form a polyesterimide insulating film 23, and Permalloy 2 is formed thereon.
After forming No. 4, patterning was performed by a usual method. Deterioration of the conductor 25 was prevented, and stress migration of the magnetic valve memory element was not observed.

FIG. 11 is a schematic sectional view of a high density wiring board. A thermally oxidized SiO ₂ film 27 is formed on the silicon wafer substrate 26.
Is formed, and the first copper wiring 29 is formed on the film. Then, the second copper wiring 2 is formed through the insulating film 28.
9 is formed, and the insulating film 28 is further formed thereon. Pb / Sn electrode 3 via Cr / Ni / Au film 30
1 is provided. As the insulating film 28, the polyesterimide precursor varnish of Example 5 was spin-coated, and then a patterned film was formed from polyesterimide cured at 200 ° C. In the copper wiring of the high-density wiring board of this example, dissolution of copper by carboxylic acid was suppressed, and deterioration of the film was not recognized.

FIG. 12 is a schematic sectional view of a flexible printed board. The polyesterimide precursor varnish of Example 1 is applied directly to a copper foil, and after the insulating film 33 of the polyesterimide film is formed by low temperature curing, the copper foil is etched into a predetermined pattern to form the wiring layer 32, A flexible printed board was created. Since the insulating film 33 was formed at 200 ° C., oxidative deterioration of the copper foil was suppressed, and a flexible printed board having a large adhesive strength with the copper foil was obtained.

FIG. 13 is a schematic sectional view of an LSI mounted printed wiring board. An LSI 39 is embedded in a metal substrate 34 by a film carrier method, and the LSI is connected to a copper wiring 35 on a solder bump via a solder ball 36. The carrier film 37 is insulated from the carrier film 37 by the interlayer insulating film 40 except for the conductive portion. Then, it is connected to the outside by the terminal 38. The polyesterimide precursor varnish of Example 2 was formed on the interlayer insulating film 40 by spin coating and cured at 200 ° C. No deterioration of the polyesterimide film due to copper was observed.

Comparative Example 1 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride 1.0 mol% and 4,
1.0 mol% of 4'-diaminodiphenyl ether was NM
A polyimide precursor varnish was prepared by reacting in P at 5 ° C. for 5 hours. Reduced viscosity ηsp / c of the obtained precursor varnish
Is 0.38 dl / g (0.5 wt%, NMP solution, 25
℃).

After diluting the above precursor varnish to 4% by weight, the transparent indium oxide electrode of the color liquid crystal display device shown in FIG. 3 was spin-coated and heat-treated at 250 ° C. for 30 minutes to 70.
A 0Å polyimide film was formed. In order to set the twist angle of the liquid crystal molecules to 260 degrees, the upper and lower substrates were rubbed at respective angles, and a spacer was sandwiched between the substrates to assemble a liquid crystal cell having a gap of 6.0 μm. The same liquid crystal material as in Example 1 was vacuum sealed in the liquid crystal cell. The attached color filter deteriorates and discolors, and the frequency change of the threshold voltage of the liquid crystal cell (30 Hz / 500 Hz) is 0.
It was 95. The cells were found to have uneven brightness. A substrate having a defective polyimide film was etched in alkali, but it took 30 minutes to peel it off.

In the case of curing the above at 220 ° C. for 5 minutes, there was no deterioration and discoloration of the color filter, but the imidization ratio was 50% or less, and more uneven brightness occurred than when curing at 250 ° C. ..

Comparative Example 2 1.0 mol% of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride and 1,1,1,3,3,3-hexafluoro-2,2 A polyimide precursor varnish was prepared in the same manner as in Comparative Example 1 except that 1.0 mol% of -bis [4- (4-aminophenoxy) phenyl] propane was used. Using this, a liquid crystal cell was prepared in the same manner as in Comparative Example 1. The attached color filter deteriorated and faded, and uneven brightness of the liquid crystal cell occurred. A substrate having a defective polyimide film was etched in alkali, but it took 30 minutes to peel it off.

In the case of curing the above at 220 ° C. for 5 minutes, there was no deterioration and discoloration of the color filter, but the imidization ratio was 50% or less, and more uneven brightness occurred than when curing at 250 ° C. ..

Comparative Example 3 The polyimide precursor varnish used in Comparative Example 1 was applied as the interlayer insulating film 10 of the semiconductor element 7 of the LSI shown in FIG. 7 and cured at 250 ° C. In addition, it is applied to the α-ray shielding layer 15 of the semiconductor memory device of FIG.
Cured at ° C.

Since the curing temperature of these is as high as 250 ° C., the thermal stress applied to the aluminum wiring layer becomes large and stress migration occurs.

[Comparative Example 4] The polyimide precursor varnish used in Comparative Example 2 was used as the interlayer insulating film 21 of the thin film magnetic head shown in FIG. 9 and the insulating film 2 of the magnetic bubble memory device shown in FIG.
3, applied to the insulating film 33 of the flexible printed circuit board,
Cured at 250 ° C. As a result, the conductor coil, permalloy, copper plate and the like deteriorated.

[0068]

EFFECT OF THE INVENTION The polyimide of the present invention can be cured at a temperature of 220 ° C. or lower in a short time to give an imidization ratio of 90% or more. Further, since the polyimide film can be easily etched, it is easy to remove unnecessary films. Therefore, the film-defective substrate can be easily regenerated, and the product yield can be improved.

Further, when it is used as an insulating film, a buffer coat film or the like of various electronic devices, it is possible to suppress the occurrence of stress migration and the like, so that it is possible to provide an electronic device of excellent quality.

In particular, the occurrence of uneven brightness in the alignment film of the liquid crystal display device is small, and deterioration and fading of the attached color filter film can be prevented.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum of 2,2-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] tridecane dianhydride.

FIG. 2 is an infrared absorption spectrum of 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] cyclohexane dianhydride.

FIG. 3 is a schematic cross-sectional view of a color liquid crystal display device.

4] 2,2-bis [3,5-dimethyl-4- (3,4
1 is an infrared absorption spectrum of -dicarboxybenzoyloxy) phenyl] dodecane dianhydride.

FIG. 5 is an infrared absorption spectrum of 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] -2-methyloctane dianhydride.

FIG. 6 is an infrared absorption spectrum of 1,1-bis [4- (3,4-dicarboxybenzoyloxy) phenyl] propylcyclohexane dianhydride.

FIG. 7 is a schematic cross-sectional view of an LSI having a multilayer wiring structure.

FIG. 8 is a schematic cross-sectional view of a semiconductor memory device having an α-ray shielding layer.

FIG. 9 is a schematic cross-sectional view of a thin film magnetic head.

FIG. 10 is a schematic cross-sectional view of a magnetic bubble memory device.

FIG. 11 is a schematic cross-sectional view of a high-density wiring board.

FIG. 12 is a schematic cross-sectional view of a flexible printed board.

FIG. 13 is a schematic cross-sectional view of an LSI-installed printed wiring board.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Glass substrate, 2 ... Color filter, 3 ... Overcoat film, 4 ... Electrode, 5 ... Alignment film, 6 ... Liquid crystal layer, 7,34
... Substrate, 8 ... SiO ₂ film, 9, 32 ... Wiring layer, 10 ... Polyester imide film, 11 ... Epoxy resin, 12, 16, 2
2, 26 ... Substrate, 13 ... Memory element, 14 ... Bonding wire, 15 ... Alpha ray shielding layer, 17 ... Lower alumina, 1
8 ... Magnetic material, 19 ... Gap alumina, 20 ... Conductor coil, 21, 33, 40 ... Insulating film, 22 ... Substrate, 23, 28
... Insulating film, 24 ... Permalloy, 25 ... Conductor, 27
... SiO ₂ film, 29, 35 ... copper wiring, 30 ... Cr / Ni /
Au film, 31 ... Pb / Sn electrode, 36 ... Solder ball, 3
7 ... Carrier film, 38 ... Terminal, 39 ... LSI.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication location H01L 21/312 B 8518-4M H05K 1/03 L 7011-4E (72) Inventor Tadao Nakata Ibaraki Prefecture Hitachi, Ltd. 4026 Kujimachi, Hitachi City Hitachi Research Laboratory (72) Inventor Katsumi Kondo 4026 Kujicho, Hitachi City Hitachi City, Ibaraki Prefecture 7226 Hitachi Institute, Hitachi Research Institute (72) Inventor Shuichi Ohara Kujimachi Hitachi City, Ibaraki Prefecture 4026 Address Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Shinji Hasegawa 3300 Hayano, Mobara City, Chiba Hitachi Ltd. Mobara Factory

Claims (15)

[Claims] 1. A general formula [1]: (However, R ₁ is a C 7-18, R ₂ is a C 5-18 alkyl group, R ₃ and R ₄ are C 1-18 alkyl groups,
R ₅ and R _{6 each} represent hydrogen or an alkyl group having 1 to 18 carbon atoms, X represents an alkyl group having 1 to 4 carbon atoms, and a, b, c and d each represent an integer of 0, 1 or 2. Can be the same. ] A thermoplastic polyesterimide, which is a polymer of a composition of tetracarboxylic acid and diamine represented by 2. The heat according to claim 1, wherein the tetracarboxylic acid contains 95 to 5 mol of another tetracarboxylic acid with respect to 5 to 95 mol of the tetracarboxylic acid represented by the general formula [1]. Plastic polyester imide. 3. The diamine is represented by the general formula [2]: (Provided that R ₁ and R ₂ are alkyl groups and perfluoroalkyl groups), X ′ is a halogen atom and an alkyl group having 1 to 4 carbon atoms, and a, b, c and d are 0, 1 or 2 Indicates an integer and these may be the same. ] The thermoplastic polyesterimide according to claim 1 or 2, which is a diamine represented by the following formula. 4. The thermoplastic polyesterimide according to claim 3, wherein the diamine contains 95 to 5 mol of another diamine with respect to 5 to 95 mol of the diamine represented by the general formula [2]. 5. A liquid crystal display device comprising a pair of substrates having transparent electrodes, at least one of which is transparent, sandwiching a nematic liquid crystal exhibiting positive dielectric anisotropy, the liquid crystal display device having the general formula [1].
A liquid crystal display device characterized in that an alignment film of thermoplastic polyesterimide represented by is provided between the substrate and the liquid crystal. 6. A nematic liquid crystal having a positive dielectric anisotropy is sandwiched between a pair of substrates each having a transparent electrode and at least one of which is transparent, and a twist angle of the liquid crystal is 240 degrees or more. A super twist type liquid crystal display device, wherein the alignment film of the thermoplastic polyester imide represented by the general formula [1] is provided between the substrate and the liquid crystal layer. Liquid crystal display device. 7. A nematic liquid crystal exhibiting positive dielectric anisotropy is sandwiched between a pair of substrates having transparent electrodes, at least one of which is transparent, and a twist angle of the liquid crystal is 240 degrees or more. A color liquid crystal display device, wherein the overcoat film between the transparent electrode and the color filter is made of the thermoplastic polyesterimide represented by the general formula [1]. 8. The liquid crystal display device according to claim 5, wherein the electrode is an active matrix type electrode. 9. A semiconductor device in which wiring is provided on a semiconductor element and a surface of the semiconductor element via an insulating layer, wherein the insulating film is a thermoplastic polyesterimide represented by the general formula [1]. Semiconductor device. 10. A semiconductor device, wherein the α-ray shielding layer provided on the surface of the semiconductor device is a thermoplastic polyesterimide represented by the general formula [1]. 11. A lower magnetic material layer provided on an insulating substrate, an upper magnetic material layer insulated by an insulating layer on the lower magnetic material layer,
A thin film magnetic head having a conductor layer provided in the insulating layer, wherein the insulating layer is a thermoplastic polyesterimide represented by the general formula [1]. 12. A semiconductor device having wiring for connecting a semiconductor element mounted on a substrate and a circuit of a carrier film, and an interlayer insulating layer for insulating the wiring, wherein the interlayer insulating layer is represented by the general formula [1]. A semiconductor device, which is the thermoplastic polyesterimide shown. 13. A magnetic bubble memory device having a conductor pattern provided on a magnetic substrate and an insulating layer for insulating between the conductor pattern and an upper magnetic material pattern, wherein the insulating layer is represented by the general formula [1]. A magnetic bubble memory device characterized by being a thermoplastic polyesterimide. 14. A high-density ceramic wiring board in which metal wiring is provided on a ceramic substrate via a thin film insulating layer, wherein the thin film insulating layer is a thermoplastic polyesterimide represented by the general formula [1]. A high-density ceramic wiring board characterized by being present. 15. A flexible printed board having a flexible substrate and metal wiring provided thereon, wherein the substrate is a thermoplastic polyesterimide represented by the general formula [1]. Board.