JPH0881669A - Electrically conductive resin paste composition and semiconductor device - Google Patents

Abstract

PURPOSE: To obtain an electrically conductive resin paste composition capable of firmly bonding a semiconductor device to e.g. a metallic frame because of its high peel strength, and capable of preventing the paste layer debonding during soldering reflow, comprising an epoxy resin, specific curing agent and electrically conductive filler. CONSTITUTION: This paste composition comprises (A) pref. 5-50wt.% of an epoxy resin (pref. having two or more epoxy groups), (B) pref. 0.1-50wt.% of a curing agent comprising a reaction product between (i) an epoxy resin and (ii) a compound having both phenolic OH and carboxyl groups (e.g. diphenolic acid), and (C) pref. 20-80wt.% of an electrically conductive filler (pref. silver). It is preferable that the number ratio of the carboxyl group in the component (ii) to the epoxy group in the component (i) stand at 0.2-1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive resin paste composition, more specifically, a conductive material suitable for adhering semiconductor elements such as IC and LSI to substrates such as lead frames, ceramic wiring boards and glass epoxy wiring boards. Resin paste composition and a semiconductor device using the same.

[0002]

2. Description of the Related Art Conventionally, Au-Si eutectic, solder, conductive resin paste composition, etc. have been known as semiconductor die-bonding materials. However, in view of workability and cost reduction, conductive resin is used. Paste compositions have become widely used. However, when the conductive resin paste composition is used, there is a problem that the peeling strength is inferior to that of Au-Si eutectic and solder. In terms of high-density and high-efficiency mounting, the surface mounting method of directly soldering the leads of the semiconductor device to the substrate is the mainstream of solder mounting.
For solder mounting, reflow soldering that heats the entire substrate with infrared rays or the like is used. Since the package is heated to a high temperature of 200 ° C. or higher, moisture contained in the package, particularly in the adhesive layer or the sealing material is used. Is vaporized and wraps around between the die pad and the encapsulant, causing cracks (reflow cracks) in the package, which reduces the reliability of the semiconductor device.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and peels off strength (peel strength).
The present invention provides an improved conductive resin paste composition and a semiconductor device using the composition.

[0004]

Means for Solving the Problems The inventors of the present invention diligently studied the above-mentioned problems, and for an epoxy resin-based conductive resin paste composition, an epoxy resin was used as a curing agent.
The inventors have found that the above problems can be solved by blending a reaction product with a compound containing one or more phenolic OH groups and one or more carboxyl groups in the molecule, and arrived at the present invention. That is, the present invention relates to (A) epoxy resin,
A conductive resin paste composition containing (B) a curing agent and (C) a conductive filler, wherein (B) the curing agent is an epoxy resin and a compound having at least one phenolic OH group and one carboxyl group in each molecule. The present invention relates to a conductive resin paste composition containing a reaction product of and a semiconductor device obtained by bonding a semiconductor element and a substrate with the conductive resin paste composition and then sealing the same.

The epoxy resin (A) used in the present invention is not particularly limited, but a compound having two or more epoxy groups in one molecule is preferable from the viewpoint of curability. Examples of such epoxy resin include phenol novolac type epoxy resin [N-730S (manufactured by Dainippon Ink and Chemicals, Inc.), Quatrex-2010 (manufactured by Dow Chemical Co.)], cresol novolac type epoxy resin [YDC
N-702 (Toto Kasei Co., Ltd.), EOCN-100 (Nippon Kayaku Co., Ltd.)], bisphenol A type epoxy resin [AE
R-X8501 (manufactured by Asahi Kasei Co., Ltd.), YL-980 (manufactured by Yuka Shell Epoxy Co., Ltd.)], bisphenol F type epoxy resin [YDF-170 (manufactured by Toto Kasei Co.)], bisphenol AD type epoxy resin [R-1710 ( Mitsui Petrochemical Co., Ltd.)], polyfunctional epoxy resin [EPPN-501
(Manufactured by Nippon Kayaku Co., Ltd.), TACTIX-742 (manufactured by Dow Chemical Co., Ltd.), VG-3101 (manufactured by Mitsui Petrochemical Co., Ltd.), 1032S (manufactured by Yuka Shell Epoxy Co., Ltd.)], and epoxy resin having a naphthalene skeleton [HP -4032 (manufactured by Dainippon Ink and Chemicals, Inc.)], alicyclic epoxy resin [EHP
E-3150 (manufactured by Daicel Chemical Industries, Ltd.)], amine type epoxy resin [ELM-100 (manufactured by Sumitomo Chemical Co., Ltd.), YH-
434L (manufactured by Toto Kasei Co., Ltd.)], resorcin type epoxy resin [Denacol EX-201 (manufactured by Nagase Kasei Kogyo)], neopentyl glycol type epoxy resin [Denacol EX-211 (manufactured by Nagase Kasei Kogyo)], hexane dinel Glycol type epoxy resin [Denacol EX
-212 (made by Nagase Kasei Co., Ltd.)], ethylene / propylene glycol type epoxy resin [Denacol EX-81
0, 811, 850, 851, 821, 830, 83
2, 841, 861 (manufactured by Nagase Chemical Industry Co., Ltd.)] and the like. These epoxy resins may be used in appropriate combination. The amount of the epoxy resin (A) compounded is preferably 1.0 to 90% by weight with respect to the conductive resin paste composition,
5 to 50% by weight is more preferable.

The curing agent (B) used in the present invention includes a reaction product of an epoxy resin and a compound having at least one phenolic OH group and at least one carboxyl group in one molecule. The epoxy resin is not particularly limited, but one having two or more epoxy groups in one molecule is preferable, and the epoxy resin described above can be used. As the compound having one or more phenolic OH group and one or more carboxyl group in one molecule, diphenolic acid, dihydroxybenzoic acid, gallic acid and the like are used.

Epoxy resin and phenolic O in one molecule
The reaction with a compound containing one or more H groups and one or more carboxyl groups is carried out in the presence of a diluent, if necessary, and by adding a catalyst if necessary, and stirring at a temperature of 100 to 190 ° C. for a certain period of time. It can be carried out. As the catalyst added as necessary, tertiary amines, imidazoles, triphenylphosphine, etc. are used, and as the diluent, those which can be used as they are when they are made into a conductive paste are preferable. The compounding ratio of the epoxy resin and the compound having at least one phenolic OH group and one or more carboxyl group in one molecule is such that the compound is compounded at a ratio of 0.2 to 1 carboxyl group to 1 epoxy group of the epoxy resin. Preferably.

In the present invention, other curing agents may be used in combination with the above reaction product. The curing agent used in combination is not particularly limited, but for example, a phenol resin [H-
1 (manufactured by Meiwa Kasei Co., Ltd.)], phenol aralkyl resin [X
L-225 (manufactured by Mitsui Toatsu Chemical Co., Ltd.)], special phenol resin [PP-700-300 (manufactured by Nippon Petrochemical Co., Ltd.)], dicyandiamide (reagent), dihydrazide dihydrochloride [AD
H, PDH, SDH (manufactured by Nippon Hydrazine Industry Co., Ltd.)] and the like. The content of the other curing agent is preferably 3 parts by weight or less relative to 1 part by weight of the reaction product, and when the amount of the curing agent other than the reaction product used is more than 3 parts by weight, the peel strength is increased. The effect of improving is small. The content of the curing agent (B) is preferably 0.01 to 90% by weight, and 0.1 to 50% by weight, based on the conductive resin paste composition.
Is more preferable.

Further, a curing accelerator can be added to the conductive resin paste composition of the present invention, if necessary. As a curing accelerator, an organic boron salt [EMZ · K,
TPPK (manufactured by Hokuko Kagaku), tertiary amines and salts thereof [DBU, U-CAT 102, 106, 830, 84]
0,5002 (manufactured by San-Apro)], imidazoles [Curezol, 2P4MHZ, C17Z, 2PZ-O]
K (manufactured by Shikoku Kasei)] and the like. The compounding amount of the curing accelerator is usually 3 with respect to the conductive resin paste composition.
The amount is set to 0.0% by weight or less. The curing agent and the curing accelerator added as necessary may be used alone, or a plurality of types of curing agents and curing accelerators may be appropriately combined and used.

Conductive filler (C) used in the present invention
Is not particularly limited, various types are used,
Examples thereof include powders of gold, silver, copper, nickel, iron, aluminum, stainless steel and the like. Of these, silver is preferable because of its excellent conductivity and small ionic impurities. The shapes of these conductive metal powders include flakes, dendritic shapes, spherical shapes, and amorphous shapes, and these various shapes can be used in combination. The content of the conductive filler (C) is 5.0 to 9 with respect to the conductive resin paste composition.
5.0 wt% is preferable, and 20.0 to 80.0 wt% is more preferable.

A diluent may be added to the conductive resin paste composition according to the present invention, if necessary, in order to improve workability in preparing the paste composition and coating workability in use. it can. These diluents include
Butyl cellosolve, carbitol, butyl cellosolve acetate, carbitol ethylene glycol diethyl ether acetate, α-terpineol and other organic solvents having a relatively high boiling point, PGE (Nippon Kayaku Co., Ltd.), PP-101 (Toto Kasei Co., Ltd.), ED- 502, 503, 509 (manufactured by Asahi Denka Co., Ltd.), YED-122 (manufactured by Yuka Shell Epoxy Co., Ltd.), K
BM-403, LS-7970 (manufactured by Shin-Etsu Chemical Co., Ltd.),
TSL-8350, TSL-8355, TSL-990
5 (manufactured by Toshiba Silicone Co., Ltd.) and the like, and a reactive diluent having 1 to 2 epoxy groups in one molecule. The conductive resin paste composition according to the present invention further includes, if necessary, a silane coupling agent, an adhesiveness improving agent such as a titanium coupling agent, a nonionic surfactant, a wetting improving agent such as a fluorochemical surfactant. , A defoaming agent such as silicone oil, an ion trap agent such as an inorganic ion exchanger, and the like can be appropriately added.

To produce the conductive resin paste composition of the present invention, (A) epoxy resin, (B) curing agent, (C)
Conductive filler, together with diluents and various additives that are used as needed, can be combined or divided into agitators, rakers, triple rolls, planetary mixers, etc. It may be heated to mix, dissolve, disintegrate, knead, or disperse into a uniform paste. In the present invention, a semiconductor device can be obtained by further adhering a semiconductor element and a substrate using the conductive resin paste composition produced as described above and then sealing. In order to adhere a semiconductor element to a substrate such as a lead frame using the conductive resin paste composition of the present invention, first, the conductive resin paste composition is applied on the substrate by a dispensing method, a screen printing method, a stamping method or the like. After that, the semiconductor element may be pressure-bonded, and then, heat-cured by using a heating device such as an oven or a heat block. Further, after the wire bonding step, the semiconductor device can be completed by sealing by a usual method.

[0013]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto. The epoxy resin and curing agent used in Examples and Comparative Examples were those prepared as follows. (1) Preparation of Epoxy Resin (A) YDF-170 (Toto Kasei Co., Ltd., trade name, bisphenol F type epoxy resin, epoxy equivalent = 170) 7.5 parts by weight and YL-980 (Okaka Shell Epoxy Co., 7.5 parts by weight of trade name, bisphenol A type epoxy resin, epoxy equivalent = 185) was heated to 80 ° C. and stirred for 1 hour to obtain a uniform epoxy resin solution.

(2) Preparation of curing agent (B) 1) Preparation of reaction product solution (1) Denacol 810 (manufactured by Nagase Chemical Industry Co., Ltd., trade name, ethylene propylene glycol type epoxy resin, epoxy equivalent = 112) 30 weight 40 parts by weight of dihydroxybenzoic acid (reagent, carboxylic acid equivalent = 154) to 12 parts by weight.
Stir at 0 ° C., sample at regular intervals, cool to room temperature when the reaction rate by acid value measurement with a potassium hydroxide alcohol solution becomes 95% or more, and add PP-101 (Toto Made by Kasei Co., trade name, alkylphenyl glycidyl ether, epoxy equivalent = 23
0) Add 30 parts by weight and heat to 80 ° C. and stir to obtain a reaction product solution of an epoxy resin and dihydroxybenzoic acid.
I got (1). 2) Preparation of phenol resin solution 1 part by weight of H-1 (manufactured by Meiwa Kasei Co., Ltd., trade name, phenol novolac resin, OH equivalent = 106) and PP-101 as a diluent (trade name of Toto Kasei Co., Ltd., alkylphenylglycidyl) 2 parts by weight of ether and epoxy equivalent = 230) were heated to 100 ° C., and stirring was continued for 1 hour to obtain a uniform phenol resin solution.

Example 1 The epoxy resin, the reaction product solution, PP-101 as a diluent and 2P as a curing accelerator in the compounding ratios shown in Table 1 were used.
4MHZ (manufactured by Shikoku Kasei, trade name, imidazoles) and TCG-1 (manufactured by Tokuriki Kagaku Kenkyusho, trade name, silver powder) as a conductive filler are mixed and kneaded using a triple roll, and then 5 torr ( The defoaming treatment was performed for 10 minutes under the conditions of Torr) to obtain a conductive resin paste composition. The characteristics (viscosity, adhesive strength and peel strength) of this conductive resin paste composition were examined by the methods described below. The results are shown in Table 1, and it was confirmed that this composition exhibits a strong peel strength.

(1) Viscosity: The viscosity (Pa · s) at 25 ° C. was measured using an EHD type rotational viscometer (manufactured by Tokyo Keiki Co., Ltd.). (2) Adhesive strength: About 200 μg of the conductive resin paste composition was applied on a copper frame with Ag plating, and 2 mm was applied on this.
A × 2 mm Si chip (thickness: about 0.4 mm) was pressure-bonded, placed on a heat block set at 200 ° C., and heated for 60 seconds. The shear adhesive strength (kg / chip) at room temperature was measured using an automatic adhesive strength tester (manufactured by Dege, Microtester). (3) Peel strength: About 3.2 mg of the conductive resin paste composition was applied on 42 alloy, and S of 8 mm × 8 mm was applied on this.
An i-chip (thickness 0.4 mm) was pressure-bonded, placed on a heat block set at 200 ° C., and heated for 60 seconds. Using an automatic adhesive force device (made by Hitachi Chemical Co., Ltd.), 2
The peel strength (kg / chip) at 40 ° C. was measured.

[0017]

[Table 1]

Example 2 A conductive resin paste composition was prepared in the same manner as in Example 1 except that the reaction product solution and the phenol resin solution described above were mixed as the curing agent in the proportions shown in Table 1. Obtained. The characteristics of this composition were examined in the same manner as in Example 1, and the results are shown in Table 1. It was confirmed that even when this composition was used, a strong peel strength was exhibited.

Example 3 Denacol 212 (manufactured by Nagase Kasei Co., Ltd., trade name, 1,6-hexanediol type epoxy resin, epoxy equivalent = 150) was used instead of Denacol 810 in the reaction product solution (1) of Example 1. Reaction product solution obtained using (2)
A conductive resin paste composition was obtained in the same manner as in Example 1 except that was used. The characteristics of this composition were examined in the same manner as in Example 1, and the results are shown in Table 1. It was confirmed that even when this composition was used, a strong peel strength was exhibited.

Comparative Examples 1 and 2 In Example 1, YDF was used as the epoxy resin (A).
170 and YL-980 were each prepared by blending 8.5 parts by weight, and a phenol resin solution alone was used as a curing agent without using the reaction product.
A conductive resin paste composition was obtained in the same manner as in Example 1 except that the compounding amount shown in was used. The properties of each of the obtained compositions were examined in the same manner as in Example 1, and the results are shown in Table 1. The peel strength was low when any of the compositions was used.

[0021]

According to the conductive resin paste composition of the present invention, a semiconductor element such as an IC or LSI can be firmly adhered to a metal frame, a ceramic substrate, an organic substrate or the like, and a paste layer at the time of solder reflow can be formed. Since peeling can be suppressed, occurrence of reflow cracks can be reduced and reliability as a semiconductor device can be improved.

Claims (2)

[Claims] 1. A conductive resin paste composition comprising (A) epoxy resin, (B) curing agent and (C) conductive filler, wherein (B) curing agent is epoxy resin and phenolic OH in one molecule. A conductive resin paste composition comprising a reaction product of a compound having one or more groups and one or more carboxyl groups. 2. A semiconductor device obtained by bonding a semiconductor element and a substrate with the conductive resin paste composition according to claim 1 and then sealing the same.