JPH07326635A - Adhesive agent and semiconductor device - Google Patents

Abstract

PURPOSE:To provide adhesive agent which reduces generation of reflow crack at the time of solder reflow, and can improve the reliability as a semiconductor device, when it is used as the die bonding material of a semiconductor device. CONSTITUTION:The adhesive agent contains the following; (1) reaction product of acrylonitrile-butadiene copolymer having carboxylic radical on the end, and organic compound having acrylic radical or methacrylic radical and epoxy radical, (2) organic compound having acrylic radical or methacrylic radical, and (3) free-radical polymerization initiator. A semiconductor element is bonded to a retaining part member by using the adhesive agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive and a semiconductor device, and more particularly to an adhesive and a semiconductor device using the same which can provide a highly reliable semiconductor device free from reflow cracks during reflow soldering.

[0002]

2. Description of the Related Art Conventionally, as a method of joining a lead frame (support member) of a semiconductor element when manufacturing a semiconductor device,
(1) A method of using an inorganic material such as a gold-silicon eutectic as an adhesive, (2) Dispersing silver powder or the like in an organic material such as an epoxy resin-based or a polyimide resin-based to form a paste, and using this as an adhesive There is a method to use. However, the former method has a high cost and is 350 ° C to 40 ° C.
Since a high heat treatment of about 0 ° C. is required, the adhesive is hard, and the chip is broken by thermal stress, the latter method using a silver paste containing silver powder has recently become the mainstream. In this method, generally, a silver paste is applied to a die pad of a lead frame by using a dispenser or a stamping machine, and then a semiconductor element is die-bonded and heat-cured to be bonded. As a method of heat curing, a batch method of curing in an oven,
There is an in-line method of curing on a heated plate. Further, this semiconductor device is mounted by soldering on the substrate after sealing the outside with a sealing material. Currently, for high-density and high-efficiency mounting, the most common solder mounting method is a surface mounting method in which a lead frame of a semiconductor device is directly soldered to a substrate. For solder mounting, reflow soldering that heats the entire substrate with infrared rays or the like is used, and the package is heated to a high temperature of 200 ° C. or higher. As a result, moisture contained in the package, especially in the adhesive layer or the encapsulant, evaporates and wraps around between the die pad and the encapsulant, causing cracks (reflow cracks) in the package and reducing the reliability of the semiconductor device. There was a drawback to

[0003]

SUMMARY OF THE INVENTION The present invention eliminates the above-mentioned drawbacks of the prior art, and provides an adhesive free from reflow cracks and a semiconductor device using the same.

[0004]

The present invention comprises (1) a reaction product of an acrylonitrile-butadiene copolymer having a carboxyl group at the terminal and an organic compound having an acryl group or a methacryl group and an epoxy group, and (2) an acryl. The present invention relates to an adhesive containing an organic compound having a radical or a methacrylic group and (3) a free radical polymerization initiator, and a semiconductor device obtained by joining a semiconductor element to a supporting member using the adhesive.

The acrylonitrile butadiene copolymer having a terminal carboxyl group used in the present invention is a known compound, for example, liquid polybutadiene CTB.
N-1300 × 31, CTBN-1300 × 8 (both manufactured by Ube Industries, Ltd.) and the like can be mentioned.

Examples of the organic compound having an acrylic group or a methacrylic group and an epoxy group used in the present invention include glycidyl acrylate and glycidyl methacrylate.

The reaction product in the present invention comprises the acrylonitrile butadiene copolymer having a carboxyl group at the terminal and the organic compound having an acryl or methacryl group and an epoxy group at 10/90 to 90/10.
It can be obtained by reacting at 80 to 120 ° C. for about 30 minutes to 6 hours at a ratio of (parts by weight). A solvent may be used during the reaction, if necessary. As the solvent, butyl cellosolve,
An organic solvent having a relatively high boiling point such as carbitol, butyl cellosolve acetate, carbitol acetate, ethylene glycol diethyl ether, and α-terpineol can be used.

Organic compounds having an acrylic group or a methacrylic group used in the present invention are already known compounds, for example, alicyclic acrylate FA-513A, alicyclic methacrylate FA-513M (manufactured by Hitachi Chemical Co., Ltd.),
Alicyclic diacrylate R-684 (manufactured by Nippon Kayaku Co., Ltd.), aliphatic diacrylate HDDA (manufactured by Nippon Kayaku Co., Ltd.), aliphatic dimethacrylate SR-2000A (SARTOMER).
Company), NPG, 1.3BG, 4G, 10G (manufactured by Shin-Nakamura Chemical Co., Ltd.), aromatic dimethacrylate BPE-100, B
Examples include PE-200, BPE-500, BPE-1300 (manufactured by Shin-Nakamura Chemical Co., Ltd.).

The free radical polymerization initiator of the present invention is not particularly limited, and examples thereof include Perkmill D and Niper D (both manufactured by NOF Corporation).

Two or more kinds of the above-mentioned acrylonitrile-butadiene copolymer having a carboxyl group, an organic compound having an acrylic group or a methacrylic group and an epoxy group, an organic compound having an acrylic group or a methacrylic group and a free radical polymerization initiator are used. You may use in combination.

In the present invention, from the viewpoint of reflow crack resistance, 50 to 40 organic compounds having an acryl group or a methacryl group are added to 100 parts by weight of the above reaction product.
0 parts by weight and a free radical polymerization initiator of 0.1-10
It is preferably used in the range of parts by weight.

A filler such as silica powder, alumina powder, or silver powder is used in the adhesive according to the present invention, if necessary, and silver powder is preferred, and there is no limitation in particle size, shape, etc., and flakes,
Dendritic, spherical, and irregular shapes can be used. For example, Silvest TCG-1 (manufactured by Tokuriki Kagaku Kenkyusho), Silflakes Agc-A (manufactured by Fukuda Metal Foil & Powder Industry Co., Ltd.), etc. The filler is usually used in the range of 50 to 85% by weight with respect to the adhesive.

The adhesive according to the present invention further comprises a silane coupling agent such as KBM-573 (manufactured by Shin-Etsu Chemical Co., Ltd.) and an adhesive strength improving agent such as a titanium coupling agent, if necessary.
An anionic surfactant, a wetting improver such as a fluorine-containing surfactant, a defoaming agent such as silicone oil, and the like can be appropriately added.

The adhesive according to the present invention comprises, for example, an acrylonitrile-butadiene copolymer having a carboxyl group at the terminal, an organic compound having an acryl group or a methacryl group and an epoxy group, and optionally an organic solvent as described above. Is reacted at a temperature of 80 ° C. to 120 ° C. in a flask to give a varnish, and the varnish is obtained by mixing an organic compound having an acrylic group or a methacrylic group, a free radical polymerization initiator and, if necessary, a filler. Examples of the mixing device include a triple roll, a planetary mixer, a smelting machine, and a ball mill. The adhesive according to the present invention is preferably used as a semiconductor element adhesive used when bonding a semiconductor element to a supporting member such as a lead frame.

A semiconductor device using the adhesive according to the present invention is manufactured through the following manufacturing steps. That is, after applying the adhesive of the present invention to a supporting member such as a lead frame by a dispensing method using an injection cylinder, a stamping method, screen printing, etc., the semiconductor device is pressure-bonded, and then a hot air circulation dryer, a heat block, etc. The semiconductor device is bonded to the support member by heating and curing using the above heating device, and then the semiconductor device is manufactured through the usual wire bonding process and sealing process.

[0016]

EXAMPLES The present invention will be described below with reference to examples. Example 1 20 parts by weight of CTBN-1300 × 8 (liquid polybutadiene, trade name of Ube Industries Ltd.) was added to 1 part of glycidyl acrylate.
0 parts by weight and 10 parts by weight of butyl cellosolve acetate were added, and the mixture was heated to 100 ° C. and stirred for 1 hour to obtain a varnish.
Then, the mixture was cooled to 25 ° C., and R-684 (alicyclic diacrylate, trade name by Nippon Kayaku Co., Ltd.), Perkmill D (radical polymerization initiator, trade name by NOF CORPORATION) silver powder TCG-1
(Tokuriki Chemical Laboratory product name) was mixed with a compounding ratio (parts by weight, the same applies hereinafter) shown in Table 1 using a raisher machine to obtain an adhesive. The following solder reflow crack test was conducted using this adhesive. The test results are shown in Table 1.

Example 2 5 parts by weight of glycidyl methacrylate and 10 parts by weight of butyl cellosolve acetate were added to 20 parts by weight of CTBN-1300 × 8 (liquid polybutadiene, trade name of Ube Industries Ltd.), and the mixture was heated to 100 ° C. and stirred for 1 hour. Got a varnish.
Then, the mixture was cooled to 25 ° C., SR-2000A (aliphatic dimethacrylate, product name manufactured by SARTMER Co., Ltd.), Park Mill D (radical polymerization initiator, product name manufactured by NOF CORPORATION), and silver powder TCG-1 (product manufactured by Tokuriki Chemical Laboratory Co., Ltd.). Name)
An adhesive was obtained by mixing the compounding ratios shown in (1) with a raider. The following solder reflow crack test was conducted using this adhesive. The test results are shown in Table 1.

Example 3 To 20 parts by weight of CTBN-1300 × 31 (liquid polybutadiene, trade name of Ube Industries, Ltd.) was added 10 parts by weight of glycidyl methacrylate and 10 parts by weight of butyl cellosolve acetate, and the mixture was heated to 100 ° C. and stirred for 1 hour. Got a varnish. Then, the mixture was cooled to 25 ° C., FA-513A (alicyclic acrylate, trade name manufactured by Hitachi Chemical Co., Ltd.), Park Mill D (radical polymerization initiator, trade name manufactured by NOF CORPORATION), and silver powder TCG-1 (Tokuriki Chemical Laboratory). (Product name) was mixed with a compounding ratio shown in Table 1 using a smelting machine to obtain an adhesive. The following solder reflow crack test was conducted using this adhesive. The test results are shown in Table 1.

Comparative Example 1 30 parts by weight of YDCN-702S (cresol novolac resin, trade name manufactured by Toto Kasei Co., Ltd.), 10 parts by weight of H-1 (phenol novolac resin, trade name by Meiwa Kasei Kogyo Co., Ltd.) and 10 parts by weight of butyl cellosolve acetate. 80 ℃
The mixture was heated to 1, and stirred for 1 hour to obtain a varnish. Then 25 ° C
The mixture was cooled to room temperature, and Curesol 2P4MHZ (trade name, manufactured by Imidazole Shikoku Kasei Kogyo Co., Ltd.) and silver powder TCG-1 (trade name, manufactured by Tokuriki Kagaku Kenkyusho) were mixed at a compounding ratio shown in Table 1 to obtain an adhesive. . The following solder reflow crack test was conducted using this adhesive. The test results are shown in Table 1.

Comparative Example 2 35 parts by weight of Epicoat 1001 (bis A type epoxy resin, trade name manufactured by Yuka Shell Epoxy Co.), 10 parts by weight of H-1 (phenol novolac resin, trade name manufactured by Meiwa Kasei Kogyo Co., Ltd.) and butyl cellosolve acetate. Add 10 parts by weight, 80
The mixture was heated to ℃ and stirred for 1 hour to obtain a varnish. Then 25
After cooling to ℃, Curesol 2P4MHZ (trade name of Imidazole Shikoku Kasei Kogyo Co., Ltd.) and silver powder TCG-1 (trade name of Tokoriki Chemical Laboratory Co., Ltd.) were mixed with a compounding ratio shown in Table 1 to obtain an adhesive. It was The following solder reflow crack test was conducted using this adhesive. The test results are shown in Table 1.

Solder Reflow Crack Test Method Using the adhesives obtained in Examples and Comparative Examples, the following lead frames and silicon chips were cured and adhered under the following curing conditions. Then, it was sealed with an epoxy sealing material (trade name CEL-4620) manufactured by Hitachi Chemical Co., Ltd. to obtain a solder reflow test package. The package was allowed to absorb moisture for 48 hours in a constant temperature and humidity chamber in which the temperature and humidity were set to 85 ° C. and 85%, respectively. 215 ℃ /
Solder reflow was performed under a reflow condition of 90 seconds, and the number of external cracks generated in the package was observed with a microscope (magnification: 15 times). The number of cracked samples is shown for five samples. Chip size: 8mm x 10mm Package: QFP, 14mm x 20mm x 2mm Frame: 42 alloy Curing conditions: Raise to 180 ° C in 30 minutes, cure at 180 ° C for 1 hour

[0022]

[Table 1]

According to Table 1, in the comparative example, external cracks are generated in all the packages, leading to a decrease in reliability of the semiconductor device. However, the adhesive of the present invention suppresses the generation of external cracks in the package and improves reliability. It is shown that a highly versatile package can be obtained.

[0024]

The adhesive according to the present invention, when used as a die-bonding agent for a semiconductor device, can suppress the peeling of the paste layer during solder reflow, reduce the occurrence of reflow cracks, and provide a semiconductor device. The reliability of can be improved.

Claims (4)

[Claims] 1. A reaction product of (1) an acrylonitrile-butadiene copolymer having a carboxyl group at an end and an organic compound having an acryl group or a methacryl group and an epoxy group, and (2) an organic compound having an acryl group or a methacryl group. And (3) an adhesive containing a free radical polymerization initiator. 2. The adhesive according to claim 1, further comprising a filler. 3. The adhesive according to claim 2, wherein the filler is silver powder. 4. A semiconductor device obtained by adhering a semiconductor element to a support member using the adhesive according to claim 1.