JP5442929B2 - Epoxy resin composition for sealing and semiconductor device using the same - Google Patents

Description

  The present invention relates to an epoxy resin composition for sealing and a semiconductor device sealed using the same.

  In the sealing of electrical and electronic parts and semiconductor devices, low-pressure transfer molding using an epoxy resin composition as a sealing material has become the mainstream. In such a sealing method using an epoxy resin composition, a resin composition in which an o-cresol novolak type epoxy resin is blended as a resin component and a phenol novolak as a curing agent component is mainly used.

  On the other hand, as electronic components such as integrated circuits (ICs), large scale integrated circuits (LSIs), and very large scale integrated circuits (VLSIs) and semiconductor devices have become increasingly dense and highly integrated, their mounting methods have been inserted. It is changing from mounting to surface mounting. However, since surface mount packages are directly exposed to the solder temperature, if the package absorbs moisture, moisture absorbed rapidly expands during soldering, causing peeling inside the package or causing package cracks. It becomes. For this reason, the sealing material with favorable crack tolerance at the time of soldering, what is called reflow crack resistance, was calculated | required.

  In order to solve this problem, for example, it is conceivable to suppress moisture absorption of the package using a sealing material in which an inorganic filler is highly filled. However, since the fluidity at the time of molding of the sealing material is reduced due to the high filling of the inorganic filler, as a result, a significant improvement in reflow crack resistance cannot be expected.

Therefore, the present applicant contains an epoxy resin, a curing agent, an inorganic filler, and a diphenyl disulfide derivative as a specific component, and the content of the diphenyl disulfide derivative is 0.01 to the total amount of the resin composition. The semiconductor sealing resin composition (for example, refer patent document 1) which is -1weight% is proposed. Moreover, the resin composition for semiconductor sealing containing biphenyl type epoxy resin and biphenyl aralkyl type epoxy resin as an epoxy resin (for example, refer patent document 2), and semiconductor sealing containing terpene phenol resin as an epoxy resin hardening | curing agent Resin compositions (see, for example, Patent Document 3) have also been proposed.
JP 2006-028476 A JP 2004-107584 A Japanese Patent No. 3555803

  The resin composition for encapsulating semiconductors in Patent Documents 1 to 3 has good peeling resistance after moisture absorption reflow and has good reflow crack resistance. However, various approaches are conceivable for improving the reflow crack resistance of the sealing material, and it is the actual situation that a sealing material excellent in reflow crack resistance is still desired.

  This invention is made | formed in view of the situation as mentioned above, and makes it the subject to provide the epoxy resin composition for sealing excellent in reflow crack resistance.

  The present invention is characterized by the following in order to solve the above problems.

1stly, the epoxy resin composition for semiconductor sealing of this invention contains an epoxy resin, a phenol resin, and an inorganic filler as an essential component , and following Formula (1)

で表されるテルペンジフェノール樹脂であり、前記式（２）で表されるテルペンジフェノール樹脂の含有量がフェノール樹脂の全体量に対して４０〜１００質量％であり、無機充填材の含有量がエポキシ樹脂組成物の全体量に対して８５〜９３質量％であることを特徴とする。

The content of the terpene diphenol resin represented by the formula (2) is 40 to 100% by mass with respect to the total amount of the phenol resin, and the content of the inorganic filler Is 85-93 mass% with respect to the whole quantity of an epoxy resin composition, It is characterized by the above-mentioned.

Second, in the first epoxy resin composition for encapsulating a semiconductor , the epoxy resin contains an epoxy resin represented by the formula (1) and a biphenyl type epoxy resin .

Third , in the first or second epoxy resin composition for encapsulating a semiconductor, the phenol resin contains a terpene diphenol resin represented by the formula (2) and a phenol aralkyl resin. And

Fourthly, the semiconductor device of the present invention is characterized by being sealed with any one of the above-mentioned epoxy resin compositions for sealing a semiconductor.

According to the first, second, and third inventions, the epoxy resin represented by the formula (1), the terpene diphenol resin represented by the formula (2), and an inorganic filler are contained. When the content of the material is 85 to 93% by mass with respect to the total amount of the epoxy resin composition, the moisture resistance and adhesion after moisture absorption reflow after molding can be improved, and the reflow crack resistance can be improved. it can.

Further, by epoxy resin represented by the front following formula (1) is 30 to 70% by weight, based on the total weight of the epoxy resin, it is possible to further improve the reflow crack resistance.

Furthermore , when the terpene diphenol resin represented by the formula (2) is 40 to 100% by mass with respect to the total amount of the phenol resin, the adhesion is surely increased, and the reflow crack resistance is further improved. be able to.

And since the semiconductor device of the said 4th invention is manufactured by carrying out sealing molding using the said epoxy resin composition for semiconductor sealing, it becomes the thing excellent in reflow crack resistance.

  The epoxy resin composition for sealing of the present invention contains an epoxy resin, a phenol resin, and an inorganic filler as essential components.

  The epoxy resin is an epoxy resin represented by the above formula (1), and the phenol resin is a terpene diphenol resin represented by the above formula (2). And an inorganic filler makes the content become the range of 85-93 mass% with respect to the whole quantity of an epoxy resin composition. Thereby, about the sealing material using this epoxy resin composition, the moisture resistance and adhesiveness after the moisture absorption reflow after shape | molding the sealing material can be improved, and reflow crack resistance can be improved.

  The epoxy resin represented by the formula (1) is used as all of the epoxy resin in the epoxy resin composition of the present invention or together with other epoxy resins. The other epoxy resin in this case may be various epoxy resins generally used for semiconductor encapsulation, and is not particularly limited. For example, biphenyl type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol type epoxy resin, stilbene type epoxy resin, triphenolmethane type epoxy resin, phenol aralkyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy Examples thereof include resins. These are not limited to one type, and a plurality of types may be used in combination.

  The content of the epoxy resin represented by the formula (1) is preferably 30 to 70% by mass with respect to the total amount of the epoxy resin, and thereby has low hygroscopicity, high adhesion, and reflow crack resistance. It can be improved effectively. If it is less than 30% by mass, the effect of the epoxy resin represented by the formula (1) cannot be sufficiently exhibited, and the reflow crack resistance may not be improved. If it exceeds 70% by mass, the melt viscosity is high, and defects such as gold wire deformation may occur.

  The phenol resin of the present invention is used as a curing agent. And the terpene diphenol resin represented by said Formula (2) is used as the whole phenol resin, or with another phenol resin. Other phenol resins in this case may be various phenol resins generally used for semiconductor encapsulation, and are not particularly limited. For example, various polyhydric phenol compounds such as phenol novolak resin, cresol novolak resin, phenol aralkyl resin, naphthol aralkyl resin, or naphthol compounds can be used. These are not limited to one type, and a plurality of types may be used in combination.

  The content of the terpene diphenol resin represented by the formula (2) is preferably 40 to 100% by mass with respect to the total amount of the phenol resin, whereby good adhesion can be obtained. The reflow crack resistance can be effectively improved. If it is less than 40% by mass, the effect of the phenol resin represented by the formula (2) cannot be sufficiently exhibited, and good adhesion may not be obtained effectively, which is not preferable.

  As described above, the content of the inorganic filler in the present invention is 85 to 93% by mass with respect to the total amount of the epoxy resin composition. If it is less than 85% by mass, sufficient low hygroscopicity and low linear expansion cannot be obtained, and the desired reflow crack resistance cannot be obtained. When it exceeds 93 mass%, fluidity | liquidity will fall and malfunctions, such as a gold wire deformation | transformation, will arise by high viscosity. The kind of the inorganic filler is not particularly limited as long as it is generally used for semiconductor encapsulation. Examples thereof include fused silica, crystalline silica, alumina, silicon nitride, and aluminum nitride.

  As described above, the epoxy resin composition for sealing of the present invention includes the epoxy resin represented by the formula (1), the terpene diphenol resin represented by the formula (2), and an inorganic filler as essential components. Although it contains, in addition to these, you may contain the various additives generally used for semiconductor sealing. Specific examples include a curing accelerator and a release material.

  The curing accelerator is not particularly limited as long as it accelerates the reaction between the epoxy group and the phenolic hydroxyl group. Examples thereof include organic phosphines such as tetraphenylphosphonium / tetraphenylborate and triphenylphosphine, tertiary amines such as diazabicycloundecene, and imidazoles such as 2-methylimidazole and 2-phenylimidazole.

  Examples of the release material include carnauba wax, polyethylene wax, stearic acid, montanic acid, carboxyl group-containing polyolefin, and the like.

  If necessary, silane coupling agents such as γ-glycidoxypropyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane, phosphorus flame retardants, bromine compounds, flame retardants such as antimony trioxide, carbon black, organic A coloring agent such as a dye or a modifying agent such as a silicone rubber powder whose surface is coated with a silicone resin can be added.

  The epoxy resin composition for sealing according to the present invention as described above is blended with the above epoxy resin, phenol resin, inorganic filler, and various additives as necessary, and mixed uniformly with a mixer or blender. Later, it can be prepared by kneading with a heating roll or a kneader. Here, the blending order of each of the above components is not particularly limited, and the kneaded product may be cooled and solidified as necessary, pulverized into pellets or powder, or used as a tablet. it can.

  And a semiconductor device is producible by carrying out sealing molding using the epoxy resin composition for sealing prepared in this way. For example, a semiconductor device in which a semiconductor element is encapsulated with a resin composition for encapsulating a semiconductor can be produced by setting a lead frame on which a semiconductor element such as an IC is mounted in a transfer mold and performing transfer molding. Is. In the semiconductor device thus obtained, the adhesion of the sealing epoxy resin composition to the semiconductor element and the lead frame is high, and moisture absorption is also suppressed, so that the reflow crack resistance is excellent.

  Hereinafter, examples will be shown, and the embodiments of the present invention will be described in more detail. Of course, the present invention is not limited to the following examples, and it goes without saying that various aspects are possible in detail.

<Examples 1-11, Comparative Examples 1-4>
Each component is blended in the blending amounts shown in Table 1, mixed for 30 minutes with a blender, homogenized, kneaded and melted with two rolls heated to 80 ° C., extruded, cooled, and then adjusted to a predetermined particle size with a pulverizer. The pulverized epoxy resin composition for sealing was obtained by pulverization.

  As the epoxy resin, epoxy resin 1: biphenyl aralkyl type epoxy resin (Nippon Kayaku NC3000 epoxy equivalent 283), epoxy resin 2: biphenyl type epoxy resin (Japan Epoxy Resin YX4000H epoxy equivalent 195) were used.

  As the phenol resin, phenol resin 1: terpene diphenol resin (YP90 hydroxyl group equivalent 192 manufactured by Yasuhara Chemical), phenol resin 2: phenol aralkyl resin (Mirex XL-225 hydroxyl group equivalent 176 manufactured by Mitsui Chemicals) were used. The epoxy resin 1 is an epoxy resin represented by the formula (1), and the phenol resin 1 is a phenol resin represented by the formula (2). The epoxy resin 2 is a commonly used epoxy resin, and the phenol resin 2 is a generally used phenol resin.

  Further, silica (FB820 manufactured by Electrochemical Co., Ltd.) as an inorganic filler, γ-glycidoxypropyltrimethoxysilane (KBM403 manufactured by Shin-Etsu Chemical Co., Ltd.) as a coupling agent, and carbon black (Mitsubishi, Ltd.) as a colorant. Chemical 40B), triphenylphosphine (Hokuko Chemical Co., Ltd. “TPP”) as a curing accelerator, and carnauba wax (Daiichi Chemical F1-100) as a release agent were used.

The above-mentioned epoxy resin composition for sealing was transfer molded (mold temperature: 175 ° C., injection pressure: 70 kgf / cm ² , molding time: 90 seconds, post-curing: 175 ° C./6 h), and the following measurement method was used. Characteristics were evaluated.
<Spiral flow>
Using a spiral flow measuring mold in accordance with ASTM D3123, molding was performed under the above transfer molding conditions, and the flow distance (cm) was measured.
<Reflow crack resistance 1>
A 128 pin QFP package having an outer dimension of 14 × 14 × 2.7 mm, in which a test chip having a size of 8 × 9 × 0.4 mm is mounted on a Cu lead frame using a silver paste, is molded under the transfer molding conditions described above. After absorbing moisture for 168 hours under the condition of 85% RH, reflow treatment was performed under the conditions of 240 ° C. and 10 seconds using an IR reflow apparatus to confirm the presence or absence of cracks. The resistance to reflow cracking was evaluated by the number of crack generation packages relative to the number of test packages.
<Reflow crack resistance 2>
The evaluation was performed in the same manner as in the reflow crack resistance 1 except that the moisture absorption time was 72 h, 96 h, and 168 h, and the reflow treatment was performed at 260 ° C. for 10 seconds using an IR reflow apparatus.

  The results are shown in Table 1.

表１にみられるように、前記式（１）で表されるエポキシ樹脂と、前記式（２）で表されるフェノール樹脂と、無機充填材とを用い、さらに無機充填材の含有量がエポキシ樹脂組成物の全体量に対して８５〜９３質量％の封止用エポキシ樹脂組成物（実施例１〜１１）は、スパイラルフローによる流動距離に問題がなく、吸湿リフロー後のクラック発生も認められず、耐リフロークラック性が向上していることが確認された。特に、前記式（１）で表されるエポキシ樹脂がエポキシ樹脂の全体量に対して３０〜７０質量％の封止用エポキシ樹脂組成物、または前記式（２）で表されるテルペンジフェノール樹脂がフェノール樹脂の全体量に対して４０〜１００質量％の封止用エポキシ樹脂組成物が耐リフロークラック性に優れていることが確認された。

As seen in Table 1, the epoxy resin represented by the formula (1), the phenol resin represented by the formula (2), and an inorganic filler were used, and the content of the inorganic filler was an epoxy. The epoxy resin composition for sealing (Examples 1 to 11) in an amount of 85 to 93% by mass with respect to the total amount of the resin composition has no problem in the flow distance due to the spiral flow, and generation of cracks after moisture absorption reflow is also observed. It was confirmed that the reflow crack resistance was improved. Particularly, the epoxy resin represented by the formula (1) is 30 to 70% by mass based on the total amount of the epoxy resin, or the terpene diphenol resin represented by the formula (2). However, it was confirmed that 40 to 100% by mass of the epoxy resin composition for sealing was excellent in reflow crack resistance with respect to the total amount of the phenol resin.

  On the other hand, the epoxy resin composition for sealing which does not use the epoxy resin represented by the formula (1) or the phenol resin represented by the formula (2) (Comparative Examples 1 to 3), the content of the inorganic filler is In the epoxy resin composition for sealing (Comparative Example 4) which is not 85 to 93% by mass with respect to the total amount of the epoxy resin composition, occurrence of cracks was observed after moisture reflow.

  As mentioned above, it was confirmed by this invention that the epoxy resin composition for sealing excellent in reflow crack resistance is provided.

Claims (4)

Contains epoxy resin, phenolic resin, and inorganic filler as essential components.

(In the formula, Gr is a glycidyl group, n is an average of 1 to 5), and the content of the epoxy resin is 30 to 70% by mass with respect to the total amount of the epoxy resin. Is the following formula (2)

The content of the terpene diphenol resin represented by the formula (2) is 40 to 100% by mass with respect to the total amount of the phenol resin, and the content of the inorganic filler Is 85 to 93 mass% with respect to the total amount of the epoxy resin composition, an epoxy resin composition for semiconductor encapsulation.   2. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the epoxy resin contains an epoxy resin represented by the formula (1) and a biphenyl type epoxy resin.   The epoxy resin composition for semiconductor encapsulation according to claim 1 or 2, wherein the phenol resin contains a terpene diphenol resin represented by the formula (2) and a phenol aralkyl resin.   A semiconductor device sealed with the epoxy resin composition for semiconductor sealing according to any one of claims 1 to 3.