JPH0815190B2 - Semiconductor device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a semiconductor device having a specific protective film on its surface.

(Prior Art) The characteristics of resin-molded semiconductor parts change due to stress during molding and stress due to heat generated during operation.
Frequent serious defects such as wire cutting and breakage of boards and cases. In addition, since the resin is sealed, moisture is likely to be absorbed from the joint and corrosion of the wire due to humidity is likely to occur. As a countermeasure against these problems, a method of providing a surface protective film on a semiconductor chip has been proposed, and silicone resins and polyimide resins have been generally studied (see, for example, Japanese Patent Publication No. 19436/50).

(Problems to be solved by the invention) When a surface protective film is provided on a semiconductor chip, when a silicone resin or a polyimide resin is used, high temperature and a long time are required for curing when forming the protective film, which results in high productivity. In addition to the remarkable decrease, these materials had the drawbacks of shrinking these materials during curing and breaking the wire.

In order to solve the above-mentioned problems, polyamide polymers and polyamideimide polymers, which are similar to thermoplastic resins, are expected to be preferable materials.
It is soluble in nitrogen-containing polar solvents with a high boiling point such as dimethylacetamide and N-methylpyrrolidone, but it is hardly dissolved in general organic solvents with a low boiling point such as tetrahydrofuran, dioxane, and cyclohexanone. There was a limit. Further, there is disclosed a polyether amide imide polymer having improved solubility in a low boiling point general organic solvent based on the high heat resistance of aromatic polyimide and aromatic polyamide (JP-A-59-202259). However, since this polymer contains many amide bond units derived from aromatic dicarboxylic acids, which are disadvantageous in solvent solubility, the solvent solubility is improved to the extent that a low boiling point general organic solvent can be used as a diluting solvent. However, it was difficult to make a solution containing only a general organic solvent.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to form a film at a low temperature in a short time by dissolving a specific polyamideimide polymer in a general organic solvent having a low boiling point, which can improve productivity and relieve stress on a semiconductor chip remarkably. An object of the present invention is to provide a semiconductor device having an excellent effect of preventing defects such as cutting of wires.

(Means for Solving the Problems) The present invention relates to a semiconductor device, wherein an aromatic tricarboxylic acid or a reactive acid derivative thereof and (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each independently represent hydrogen, a lower alkyl group, a lower alkoxy group or a halogen group,
-X- is a bond, -O-, -S-, Represent. R ₅ and R ₆ each independently represent hydrogen, a lower alkyl group, a trifluoromethyl group, a trichloromethyl group or a phenyl group. The aromatic polyether amide imide polymer obtained by reacting with an aromatic diamine represented by) is obtained by coating and drying a varnish prepared by dissolving an ether compound or an alicyclic ketone compound having a boiling point of less than 180 ° C. The present invention relates to a semiconductor device having a protective film.

The aromatic polyether amide imide polymer in the present invention has high heat resistance. In addition, its solubility in solvents is remarkably excellent, and it is also characterized in that it is soluble in ether compounds and alicyclic ketone compounds with a boiling point of less than 180 ° C, which does not dissolve conventional polyimide and polyamideimide, which are generally well known. . As the ether compound having a boiling point of less than 180 ° C, for example, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, polyethylene glycol dimethyl ether, etc. are used, and as the alicyclic ketone compound, for example, cyclohexanone, 4-
There are methylcyclohexanone, 2-cyclohexanone, 4-methyl-2-cyclohexanone and the like.

Incidentally, examples of the polyethylene glycol dimethyl ether, (wherein, l represents an integer of 2 or more) general formula _{(A) H 3 C-OCH} 2 CH 2 O l CH 3 (A) is a compound represented by the boiling point Those below 180 ℃ are selected and used.
Specifically, diethylene glycol dimethyl ether,
Examples include triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether.

Examples of the aromatic diamine represented by the general formula (I) in the present invention include 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-methyl-4
-(4-Aminophenoxy) phenyl] propane, 2,2-
Bis [3-bromo-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-ethyl-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-
Propyl-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-isopropyl-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-butyl-4- (4-aminophenoxy) ) Phenyl] propane, 2,2-bis [3-sec-butyl-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-methoxy-4- (4-aminophenoxy) phenyl] propane, 2 , 2-bis [3-ethoxy-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3,5-dimethyl-4- (4-aminophenoxy) phenyl] propane,
2,2-bis [3,5-dichloro-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3,5-dibromo-
4- (4-aminophenoxy) phenyl] propane, 2,2
-Bis [3,5-dimethoxy-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-chloro-4-
(4-Aminophenoxy) -5-methylphenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-methyl-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-chloro-4- (4-aminophenoxy) phenyl] ethane, 1,1
-Bis [3-bromo-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-ethyl-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-propyl-4 -(4-Aminophenoxy) phenyl] ethane, 1,1-bis [3-isopropyl-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-butyl-
4- (4-aminophenoxy) phenyl] ethane, 1,1-
Bis [3-sec-butyl-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-methoxy-4-
(4-Aminophenoxy) phenyl] ethane, 1,1-bis [3-ethoxy-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3,5-dimethyl-4- (4-aminophenoxy) phenyl ] Ethane, 1,1-bis [3,5-
Dichloro-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3,5-dibromo-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3,5-dimethoxy-4- (4-Aminophenoxy) phenyl] ethane, 1,1-bis [3-chloro-4- (4-aminophenoxy) -5-methylphenyl] ethane, bis [4- (4-
Aminophenyloxy) phenyl] ethane, bis [3-methyl-4- (4-aminophenyloxy) phenyl] methane,
Bis [3-chloro-4- (4-aminophenoxy) phenyl] methane, Bis [3-bromo-4- (4-aminophenoxy) phenyl] methane, Bis [3-ethyl-4-]
(4-Aminophenoxy) phenyl] methane, bis [3
-Propyl-4- (4-aminophenoxy) phenyl]
Methane, bis [3-isopropyl-4- (4-aminophenoxy) phenyl] methane, bis [3-butyl-4-
(4-Aminophenoxy) phenyl] methane, bis [3
-Sec-Butyl-4- (4-aminophenoxy) phenyl] methane, bis [3-methoxy-4- (4-aminophenoxy) phenyl] methane, bis [3-ethoxy-4
-(4-Aminophenoxy) phenyl] methane, bis [3,5-dimethyl-4- (4-aminophenoxy) phenyl] methane, bis [3,5-dichloro-4- (4-aminophenoxy) phenyl] methane, bis [ 3,5-dibromo-4- (4-aminophenoxy) phenyl] methane,
Bis [3,5-dimethoxy-4- (4-aminophenoxy) phenyl] methane, bis [3-chloro-4- (4-
Aminophenoxy) -5-methylphenyl] methane, 1,
1,1,3,3,3-hexafluoro-2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1,1,3,3,3-hexachloro-2,2-bis [ 4- (4-aminophenoxy) phenyl] propane, 3,3-bis [4- (4-aminophenoxy) phenyl] pentane, 1,1-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-hexachloro-2,2-bis [3,5-dimethyl-4
-(4-Aminophenoxy) phenyl] propane, 3,3-
Bis [3,5-dimethyl-4- (4-aminophenoxy)]
Phenyl] pentane, 1,1-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,
1,1,3,3,3-hexachloro-2,2-bis [3,5-dibromo-4- (4-aminophenoxy) phenyl] propane,
3,3-bis [3,5-dibromo-4- (4-aminophenoxy) phenyl] pentane, 1,1-bis [3,5-dibromo-
4- (4-aminophenoxy) phenyl] propane, 2,2
-Bis [4- (4-aminophenoxy) phenyl] butane, 2,2-bis [3-methyl-4- (4-aminophenoxy) phenyl] butane, 2,2-bis [3,5-dimethyl-4]
-(4-Aminophenoxy) phenyl] butane, 2,2-bis [3,5-dibromo-4- (4-aminophenoxy) phenyl] butane, 1,1,1,1,3,3,3-hexafluoro-2, 2-
Bis [3-methyl-4- (4-aminophenoxy) phenyl] propane 1,1-bis [4- (4-aminophenoxy) phenyl] cyclohexane, 1,1-bis [4- (4-
Aminophenoxy) phenyl] cyclopentane, bis [4- (4-aminophenyloxy) phenyl sulfone, bis [4-aminophenoxy) phenyl ether, bis [4- (3-aminophenoxy) phenyl sulfone, 4,
There are 4'-carbonylbis (p-phenyleneoxy) dianiline, 4,4'-bis (4-aminophenoxy) biphenyl and the like. Of these, 2,2-bis [4- (4-aminophenoxy) phenyl] propane is typical.
If necessary, the above diamines can be used as a mixture of two or more kinds.

Further, in the present invention, if necessary, known diamines such as 4,4'-diaminodiphenyl ether, 3,4'-diphenyl ether, 4,4'-diaminodiphenylmethane,
4,4'-diaminodiphenyl sulfone, 4,4'-benzophenone diamine, metaphenylenediamine, 4,4'-di (4-aminophenoxy) phenyl sulfone, paraphenylenediamine, 4,4'- At least one kind of di (3-aminophenoxy) phenyl sulfone, 3,3'-diaminodiphenyl sulfone and the like can be used in combination. The ratio of these diamines to the total diamines is preferably 30 mol% or less. If this ratio exceeds 30 mol%, the solubility of the polymer is adversely affected.

Further, it is preferable to use diaminosiloxane together as a diamine component in order to improve the adhesiveness with a metal. When used in combination, particularly preferable results are obtained when diaminosiloxane is used in the range of 0.2 to 40 mol% with respect to the total amount of diamine. Care must be taken because if the amount of diaminosiloxane is too large, the heat resistance tends to decrease. Diaminosiloxane can be obtained, for example, by the general formula (III) (Wherein R ₇ represents a divalent hydrocarbon group, R ₈ represents a monovalent hydrocarbon group, and m is an integer of 1 or more). R ₇ is preferably an alkylene group having 1 to 5 carbon atoms, a phenylene group or an alkyl-substituted phenylene group, and R ₈ is preferably an alkyl group or an alkoxy group having 1 to 5 carbon atoms, a phenyl group or an alkyl-substituted phenyl group. It is a base. In general formula (III), m is preferably 100 or less.
When m is too large, the ratio of the amide bond and the imide bond in the obtained polymer decreases, and the heat resistance tends to decrease. The two R ₇ may be the same or different,
A plurality of R ₈ may be the same or different from each other.

As diaminosiloxane, for example, And the like. Where m 'is 1 to
A number in the range of 100. Among the diaminosiloxanes, those of formula (a) wherein m'is 1, average 20 and average 50 are LP-7100, X-22-161A and X-22-161C, respectively.
(Both are trade names of Shin-Etsu Chemical Co., Ltd.). These diaminosiloxanes may be used alone or in combination of two or more.

The aromatic tricarboxylic acid in the present invention has 3 in the aromatic nucleus.
One carboxyl group is attached and two of the three carboxyl groups are attached to adjacent carbons. Of course, this aromatic ring may have a hetero ring introduced,
Further, the aromatic rings may be bonded to alkylene, oxygen, carbonyl group and the like. Further, a substituent that does not participate in the condensation reaction, such as alkoxy, allyloxy, alkylamino, and halogen, may be introduced into the aromatic ring. For example, as this compound trimellitate, 3,3,4 '
-Benzophenone tricarboxylic acid, 2,3,4'-diphenyl tricarboxylic acid, 2,3,6-pyridine tricarboxylic acid, 3,4,
4'-benzanilide tricarboxylic acid, 1,4,5-naphthalene tricarboxylic acid, 2'-methoxy-3,4,4'-diphenyl ether tricarboxylic acid, 2'-chlorobenzanilide-3,4,4'- And tricarboxylic acids. The above-mentioned reactive derivative of aromatic tricarboxylic acid means an acid anhydride, halide,
It means esters, amides, ammonium salts and the like. Examples of these are trimellitic anhydride, trimellitic anhydride monochloride, 1,4-dicarboxy-3-N, N
-Dimethylcarbamoylbenzene, 1,4-dicarbomethoxy-3-carboxybenzene, 1,4-dicarboxy-3-
Carbophenoxybenzene, 2,6-dicarboxy-3-carbomethoxypyridine, 1,6-dicarboxy-5-carbamoylnaphthalene, ammonium salts of the above aromatic tricarboxylic acids and ammonia, dimethylamine, triethylamine, etc. Can be given. Of these, trimellitic anhydride and trimellitic anhydride monochloride are representative.

In the present invention, the reaction method is an isocyanate method (for example, JP-B-44-19274, JP-B-45-2397,
JP-B-50-33120), acid chloride method (eg JP-B-42-15637), direct polycondensation method (eg JP-B-49-4077), melt polycondensation method (eg JP-B-SHO)
40-8910) and polycondensation by a known production method. The acid chloride method and the direct polycondensation method are preferable in view of the cost, the relative ease of procuring raw materials, the ease with which a high molecular weight product is obtained, and the solubility of the obtained polymer in an organic solvent.

 The acid chloride method will be described below.

The aromatic tricarboxylic acid anhydride monochloride is preferably 80 to 120 mol% with respect to the total amount of the diamine,
It is particularly preferable to use 95 to 105 mol% of the inorganic acid acceptor 90
A polyamidoamic acid is obtained as an intermediate by reacting in a non-reactive polar organic solvent in the presence of ˜200 mol% at minus several tens to 100 ° C., preferably −20 to 50 ° C. for several minutes to several days. At this time, the inorganic acid acceptor may be added during the reaction. Also, as the inorganic acid acceptor, triethylamine, tripropylamine, tributylamine,
Examples include tertiary amines such as triamylamine and pyridine, and 1,2-epoxides such as propylene oxide, styrene oxide, and cyclohexene oxide. The non-reactive organic solvent includes N, N-dimethylacetamide, N, N-dimethylalumamide, N-methyl-2-pyrrolidone, cresol and the like, and particularly N, N-dimethylacetamide and N-methyl-2. -Pyrrolidone is preferred. Then, in order to obtain polyamideimide from this polyamic acid, a dehydration cyclization method may be used. The dehydration cyclization methods include (1) a method of once isolating a polymer and then cyclizing by heat, (2) a method of cyclization by heat in a solution state, and (3) a chemical dehydrating agent in a solution state. Cyclization.

Regarding (1), CEEroouk (CESroo
g) Macromolecular synthesis
Syntheses) Collective Volume, Volume 1, p. 295 (1977).
It is preferable to heat at 0 to 350 ° C.

In the method (2), 80 to 400 ° C, preferably 100 to 25
By heating the solution to 0 ° C. At this time, it is preferable to use a solvent such as benzene, toluene and xylene, which is azeotropic with water.

In the method (3), the reaction is carried out in the presence of a chemical dehydrating agent at 0 to 120 ° C, preferably 10 to 80 ° C. Examples of the chemical dehydrating agent include acid anhydrides such as acetic acid, propionic acid, butyric acid, and benzoic acid. At this time, it is preferable to use pyridine or the like as a substance that promotes the cyclization reaction.

 Next, the direct polycondensation method will be described.

The aromatic tricarboxylic acid and / or its derivative (excluding the acid halide derivative) is preferably 80 to 120 mol%, particularly preferably 9%, based on the total amount of the diamine.
5 to 105 mol%, and 1 to 15 mol% of dehydration catalyst in a non-reactive polar organic solvent in the presence of 0.5 to 10 mol%
The reaction is carried out at 60 to 350 ° C, preferably 200 to 270 ° C. Examples of the dehydration catalyst include triphenyl phosphite, tricyclohexyl phosphite, phosphoric acid, triphenyl phosphonate, phosphorus compounds such as phosphorus pentoxide, boric acid, boric anhydride and the like. Examples of the non-reactive organic solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methyl-caprolactam, cresol, xylenol, chlorophenol and the like. Especially N-methyl-2-
Pyrrolidone is preferred.

The aromatic polyether amide imide polymer thus obtained has the general formula (IV) The repeating unit represented by and the general formula (V) It is considered to be a polymer in which the repeating units represented by and are appropriately bonded to each other. However, in the general formulas (IV) and (V), A is a residue obtained by removing the carboxyl group of any of the above aromatic tricarboxylic acids, and B is a residue obtained by removing the amino group of any of the above diamines. When the repeating unit of the general formula (IV) and the repeating unit of the general formula (V) are bonded to each other, one B is bonded to the other N.

Further, in the present invention, if necessary, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl Phenyltetracarboxylic dianhydride, 2,2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane dianhydride,
1,1,1,3,3,3-hexafluoro-2,2-bis [4- (2,3
-Or 3,4-dicarboxyphenoxy) phenyl] propane dianhydride and other known tetrabasic dianhydrides, terephthalic acid, isophthalic acid, phthalic acid and other known dicarboxylic acids,
Diimidedicarboxylic acid obtained by reacting the above-mentioned known diamine with trimellitic acid or a reactive derivative of trimellitic acid, the following general formula (VI) (R ₉ and R ₁₀ represent a monovalent hydrocarbon group, R ₉ and R ₁₀ may be the same or different, and n is an integer of 1 or more), preferably a tetrabasic dianhydride. In the general formula (VII), R ₁₁ and R ₁₂ are methyl groups, and n is 1 or 2, such as a tetrabasic dianhydride can be used in combination as an acid component. The ratio of these tetrabasic acid dianhydride, dicarboxylic acid and diimidedidicarboxylic acid to the total acid component is preferably 30 mol% or less. If this ratio exceeds 30 mol%, the solubility or heat resistance of the polymer is adversely affected.

The reaction solution obtained as described above is poured into a large excess of a solvent that is compatible with the lower alcohol such as methanol and the above organic solvent such as water and is a poor solvent for the resin.
The aromatic polyether amide imide in the present invention can be recovered by obtaining a precipitate, filtering the precipitate, and drying.

The aromatic polyether amide imipolymer obtained by the present invention preferably has a reduced viscosity in a 0.2% by weight dimethylformamide solution at 30 ° C. of 0.2 to 2.0 dl / g. If this reduced viscosity is too small, heat resistance and mechanical strength will decrease, and if it is too large, solubility in the solvent will decrease.

To form a protective film containing the aromatic polyether amide imide polymer, first, the polymer is dissolved in a solvent to form a varnish, and the varnish is potted or coated on the device, and then the solvent is removed. Therefore, it is dried by heating to form a film.

In order to obtain the effect as the surface protective film, it is preferable that the film thickness after drying is 1 to 100 μm.

In addition, the polyamide-imide polymer film has good adhesiveness to metals such as Si, Al and Ni even if it is left as it is,
Further, a coupling agent such as a silane coupling agent may be added to the varnish in order to improve the adhesive strength.

The solvent used to form the varnish of the polymer is the above-mentioned ether compound or alicyclic ketone compound having a boiling point of less than 180 ° C. Nitrogen-containing polar solvents such as dimethylformamide, N-methylpyrrolidone, and dimethylacetamide, and as poor solvents, general organic solvents other than the above-mentioned good solvents, such as ketones, esters, alcohols, ethers, cellosolves, and fats. Group, alicyclic and aromatic hydrocarbons, halogenated hydrocarbons, water and the like may be used in combination, but the amount is preferably limited to a small amount.

When an ether compound or alicyclic ketone compound having a boiling point of less than 180 ° C is used as a solvent, a protective film can be obtained by drying at a relatively low temperature (for example, room temperature to 100 ° C) in a short time, so that stress on the device is significantly reduced. It can be relaxed, and the effect of preventing defects such as cutting wires is particularly excellent.

Transistors and memories are used as semiconductor device elements.
There are IC elements, hybrid IC elements, etc. It also includes those collectively referred to as semiconductor chips.

Examples of the protective film by application include semiconductor junction coats, memory IC α-ray shield films, surface-mount IC buffer coats, and the like. For a semiconductor junction coating, an inorganic powder generally added to improve dielectric properties, such as SiO ₂ , Al ₂ O ₃ , ZrO ₂ , Pb ₃ O _4, etc., is used as the aromatic polyether amide imide polymer 100. It can be added in the range of 1 to 200 parts by weight with respect to parts by weight (added at the above varnish stage). For α-ray shielding, if the uranium and thorium contents are refined to 0.1 ppb or less, the generation of α-rays from the aromatic polyether amide imide polymer itself is not a practical problem. Effective. Purification can be performed by recrystallization, sublimation, distillation or the like of the polymer raw material or solvent, and also by reprecipitation purification of the polymer itself. In addition, the sodium content must be 1ppm or less to reduce corrosion and leakage during the humidity resistance test, but this can be performed in the same process as the above purification.

The semiconductor device according to the present invention may be further sealed with epoxy resin or the like.

(Examples) Next, the present invention will be described based on Examples, but the present invention is not limited to these.

Example 1 Under nitrogen, 164 g (400 mmol) of 2,2-bis [4- (4-aminophenoxy) phenyl] propane and 34.8 of propylene oxide were placed in a four-necked flask equipped with a thermometer, a stirrer, a nitrogen introducing tube, and a cooling tube. g (600 mmol) was added and dissolved in 564 g of dimethylacetamide. Cool the solution to 0 ° C.,
84.2 g of trimellitic anhydride monochloride at this temperature
(400 mmol) was added so that the temperature did not exceed 5 ° C.

After stirring at room temperature for 3 hours, add 200 g of acetic anhydride and 50 g of pyridine.
Stirring was continued at 60 ° C for one day.

The obtained reaction solution was poured into methanol to isolate the polymer. After drying this, it was again dissolved in dimethylformamide, and this was put into methanol to purify the aromatic polyether amide imide silicon polymer and dried under reduced pressure.

The reduced viscosity (ηsp / c) of this polymer (dimethylformamide 0.2% by weight solution, measured at 30 ° C, the same below) is 0.73dl / g.
It was.

5 g of the aromatic polyether amide imide polymer powder thus obtained was dissolved in 95 g of tetrahydrofuran to form a 5% by weight varnish, which was applied on the surface of the power transistor element as shown in FIG. After standing for a minute, a film of aromatic polyether amide imide polymer having a thickness of 5 μm was formed on the surface of the device. The residual solvent at this time was 0.8%. After that, transfer molding was performed using epoxy resin molding material and sealing was performed. The failure rate of this semiconductor device after 1000 hours at 80 ° C. and 90% RH was 0/100 (0 out of 100), which was excellent.

FIG. 1 is a schematic perspective view of this semiconductor device, in which a heat dissipation fin 1 and a lead wire 2 are connected to a substrate 3, a power transistor element 4 is mounted on the substrate 3, and the element 4 and the lead are connected. A wire 5 is connected to the wire 2. Element 4
Is covered with an aromatic polyether amide imide polymer film 6 and is sealed with an epoxy resin molding material 7.

Example 2 5 g of the polyamide-imide polymer obtained in Example 1 was dissolved in 95 g of dioxane to give a 5% by weight varnish. This varnish was applied to the surface of a semiconductor chip of a power transistor device similar to that of Example 1, left at room temperature for 30 minutes, and then heated at 70 ° C. for 30 minutes to form a 5 μm thick film of aromatic polyether amide imide polymer. It was formed on the device surface. The residual solvent at this time is 0.3
It was in%. After that, the semiconductor device obtained in the same manner as in the example had an excellent failure rate of 0/100 after 1000 hours at 80 ° C. and 90% RH.

Example 3 10 g of the aromatic polyether amide imide polymer obtained in Example 1 was mixed with tetrahydrofuran / cyclohexanone 80/20.
It was dissolved in 90 g of a mixed solvent (weight ratio) to prepare a 10 wt% varnish. This varnish was applied to the surface of a semiconductor chip of the same device as in Example 1 and left at room temperature for 30 minutes, then at 120 ° C.-30
After heating for a minute, a film of aromatic polyether amide imide polymer having a thickness of 10 μm was formed on the surface of the device. The residual solvent at this time was 0.5%. Thereafter, the failure rate of the semiconductor device obtained in the same manner as in Example 1 after 1000 hours at 80 ° C. and 90% RH was 0/100.
It was excellent.

Example 4 Instead of 164 g (400 mmol) of 2,2-bis [4- (4-aminophenoxy) phenyl] propane in Example 1, 172.4 g (400 mmol) of bis [4- (4-aminophenoxy) phenyl sulfone is used. Other than that, the same operation as in Example 1 was carried out to obtain an aromatic polyether amide imide polymer having a reduced viscosity of 0.91 dl / g.

5 g of this aromatic polyether amide imide polymer was dissolved in 95 g of tetrahydrofuran to form a 5% by weight varnish,
This varnish was applied to the surface of a power transistor device similar to that in Example 1, and left at room temperature for 30 minutes to form a 5 μm thick film of aromatic polyether amide imide polymer on the device surface. The residual solvent at this time was 0.8%. After this,
The semiconductor device obtained in the same manner as in Example 1 was heated to 80 ° C., 90% RH, 10
The failure rate after 00 hours was 0/100.

Example 5 Instead of 164 g (400 mmol) of 2,2-bis [4- (4-aminophenoxy) phenyl] propane of Example 1, 2,2
-Bis [4- (4-aminophenoxy) phenyl] propane 147.6 g (360 mmol) and 1.3-bis (aminopropyl)
The procedure of Example 1 was repeated except that 9.92 g (40 mmol) of tetramethyldisiloxane was used. Reduced viscosity of polymer is 0.70dl
It was / g. The failure rate of the semiconductor device using this polymer as a surface protective film after 1000 hours at 80 ° C. and 90% RH was 0/100.

Comparative Example 1 The above organisms except trimellitic anhydride were placed in a four-necked flask equipped with a stirrer, a nitrogen inlet tube, and a water content meter, and gradually stirred at 205 ° C while passing nitrogen gas.
The temperature was raised to. After keeping at the same temperature for about 1 hour, it was cooled to 175 ° C. and trimellitic anhydride was added at the same temperature for about 10 minutes. Then, the temperature was raised and the reaction proceeded in the temperature range of 205-210 ℃. Water distilled after the addition of trimellitic acid anhydride was promptly removed to the outside of the reaction system, and at the same time, the reaction was advanced while supplementing the distilled N-methylpyrrolidone. The end point of the reaction was controlled by the Gardner viscosity to obtain a polyamideimide polymer having a reduced viscosity of 0.50 (dl / g).

When the solubility of the obtained polyamide-imide polymer was examined, it was found to be insoluble in any of tetrahydrofuran, dioxane, and cyclohexanone.

(Effect of the Invention) The present invention relates to a semiconductor device using a specific polyamide-imide polymer dissolved in an ether compound and / or alicyclic ketone compound having a boiling point of 180 ° C. or less as a surface protective film of a semiconductor chip, -Since the film can be formed in a short time, the productivity can be significantly improved, the stress on the semiconductor chip can be relieved, and the semiconductor device excellent in the defect prevention effect such as the wire cutting is provided.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an example of a semiconductor device according to the present invention. Explanation of symbols 1 ... Heat dissipation fin, 2 ... Lead wire 3 ... Substrate 4 ... Power transistor element 5 ... Wire 6 ... Aromatic polyether amide imide polymer film 7 ... Epoxy resin molding material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshiyuki Mukaiyama Yoshinobu Mukaiyama 4-13-1 Higashimachi, Hitachi City, Ibaraki Hitachi Chemical Co., Ltd. Ibaraki Laboratory (72) Inventor Junichi Sakata 4-13, Higashimachi, Hitachi City, Ibaraki Prefecture No. 1 Hitachi Chemical Co., Ltd. in Ibaraki Research Institute (72) Inventor Sotoji Oshima 2-1-1 Nishi Shinjuku, Shinjuku-ku, Tokyo Inside Hitachi Chemical Co., Ltd. (56) Reference JP-A-57-64955 (JP, A)

Claims (1)

[Claims] 1. In a semiconductor device, an aromatic tricarboxylic acid or a reactive acid derivative thereof and a compound represented by the general formula (I) are provided on a surface of an element. (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each independently represent hydrogen, a lower alkyl group, a lower alkoxy group or halogen;
-X- is a bond, -O-, -S-, Wherein R ₅ and R ₆ are independently obtained by reacting with an aromatic diamine represented by hydrogen, a lower alkyl group, a trifluoromethyl group, a trichloromethyl group or a phenyl group) A semiconductor device having a protective film obtained by applying and drying a varnish obtained by dissolving an aromatic polyether amide imide polymer in an ether compound and / or an alicyclic ketone compound having a boiling point of less than 180 ° C.