JP4765310B2 - Manufacturing method of resin-encapsulated semiconductor device - Google Patents

Description

  The present invention relates to a mold release recovery resin composition for sealing a semiconductor used for recovering the mold release property of a mold for sealing used in the manufacture of a resin sealed semiconductor device, and a semiconductor device using the same It is related with the manufacturing method.

  Epoxy resin composition for semiconductor encapsulation as the integration of semiconductor elements progresses year by year and the surface mounting of semiconductor devices is promoted in the market trend of downsizing, weight reduction and high performance of electronic devices in recent years. The demand for things has become increasingly severe. Epoxy resin compositions for semiconductor encapsulation using various resins and additives that meet this requirement are prone to mold fouling during continuous molding, and mold defects such as unfilling are likely to occur. Therefore, it has become normal to periodically clean the mold surface.

  Conventionally, a semiconductor sealing mold cleaning material consists of a resin having a high molding shrinkage such as an amino resin and a filler having high hardness such as crystal-crushed silica and glass fiber. The main thing was scraping off the dirt on the mold surface. After using the cleaning material, the mold surface will be clean, but the mold release agent will also be removed, so the cured resin of the semiconductor device molded immediately after cleaning is extremely releasable. There was a problem of getting worse. Therefore, after using the cleaning material, it is necessary to mold the mold release recovery resin composition, transfer the mold release agent in the mold release recovery resin composition to the mold surface, and apply it to recover the release properties. is there.

The function of the mold release recovery resin composition is to transfer and apply the release agent to the mold surface, and to quickly recover the release property, but if a large amount of release agent is transferred, After that, there is a problem of causing oil floating or dirt on the surface of the cured resin of the molded semiconductor device. If the release agent cannot be transferred sufficiently, the release property cannot be recovered, and a large amount of the release recovery resin composition is required. There arises a problem that it is necessary to use it. Furthermore, when the releasability after recovery of releasability cannot be sustained for a long time, it is necessary to frequently use a releasable recovery resin composition, and productivity is lowered.
For this reason, a technique for improving mold release sustainability by adding an antioxidant to a montanic acid ester wax or oxidized or non-oxidized polyethylene wax as a mold release agent is disclosed (for example, see Patent Document 1). ). Although this method improves mold release sustainability, since the main chain of the mold release agent is a carbon chain, it is relatively compatible with the epoxy resin composition for semiconductor encapsulation, and is formed on the surface of the molded semiconductor device. The problem of causing oil floating and dirt could not be solved sufficiently.

JP-A-4-259513 (2-5 pages)

  The present invention relates to a mold release recovery resin composition for semiconductor encapsulation used for recovering the mold release property of a mold for encapsulation used in the production of a resin-encapsulated semiconductor device. Mold release recovery resin composition for semiconductor encapsulation, which can maintain mold release characteristics without recovering oil floatation and dirt on the surface of the semiconductor device immediately after mold release recovery, and molding using the same It is an object of the present invention to provide a method for manufacturing a resin-encapsulated semiconductor device that recovers mold releasability.

The present invention
[1] In a method for manufacturing a resin-encapsulated semiconductor device in which a semiconductor element is molded and sealed using a semiconductor-encapsulating resin composition, molding is performed using a cleaning material for cleaning the surface of a semiconductor-encapsulating mold. A step, then a step of recovering the mold release property of the molding die using the mold release recovery resin composition for semiconductor sealing, and then a step of continuously molding using the resin composition for semiconductor sealing, The mold release recovery resin composition for semiconductor encapsulation is represented by (A) an epoxy resin, (B) a phenol resin, (C) a curing accelerator, (D) an inorganic filler, (E) represented by the general formula (1) The modified organopolysiloxane, which is a reaction product of the organopolysiloxane and the epoxy resin or phenol resin, is an essential component, and the (E) modified organopolysiloxane is 0.1 to 20 weight in the total epoxy resin composition. Method of manufacturing a resin-sealed semiconductor device, wherein the contained,
It is.

（式中、Ｒ_１、Ｒ_２はアミノ基、ヒドロキシル基、エポキシ基、カルボキシル基、ヒドロキシルフェニル基から選択される基であり互いに同一であっても異なっていてもよい。Ｒ_３、Ｒ_４はアルキル基、アリール基、アラルキル基から選択される有機基であり、互いに同一であっても異なっていてもよい。重量平均分子量は１３０〜１００００の正数である。）

(In the formula, R ₁ and R ₂ are groups selected from an amino group, a hydroxyl group, an epoxy group, a carboxyl group, and a hydroxylphenyl group, and may be the same or different from each other. R ₃ and R ₄ may be different from each other. (It is an organic group selected from an alkyl group, an aryl group, and an aralkyl group, and may be the same or different from each other. The weight average molecular weight is a positive number of 130 to 10,000.)

  The mold release recovery resin composition for semiconductor encapsulation of the present invention can recover the mold release property by molding a few times, and oil is applied to the surface of the semiconductor device in the semiconductor seal molding immediately after the mold release recovery. It is industrially useful because it contributes to the improvement of productivity in the manufacture of semiconductor devices, because it can maintain a good release property for a long time without causing floating and dirt.

The present invention includes an epoxy resin, a phenol resin, a curing accelerator, an inorganic filler, and a modified organopolysiloxane that is a reaction product of an organopolysiloxane represented by the general formula (1) and an epoxy resin or a phenol resin. The mold release recovery resin composition contained in the mold can be used to recover the mold releasability of the mold, so that the mold release can be recovered with a small number of moldings. In the stop molding, the surface of the semiconductor device does not cause oil floating or dirt, and a remarkable effect can be obtained that a good releasability can be maintained for a long time.
Hereinafter, the present invention will be described in detail.

  Although it does not specifically limit as an epoxy resin used by this invention, For example, a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a biphenyl type epoxy resin, a bisphenol type epoxy resin, a stilbene type epoxy resin, a triphenolmethane Type epoxy resin, phenol aralkyl type epoxy resin, naphthalene type epoxy resin, alkyl-modified triphenol methane type epoxy resin, triazine nucleus-containing epoxy resin, dicyclopentadiene-modified phenol type epoxy resin, etc. It may be used.

The phenolic resin used in the present invention is not particularly limited. Examples thereof include phenol aralkyl resins having a phenylene and / or diphenylene skeleton, and these may be used alone or in combination.
The blending ratio of the epoxy resin and the phenol resin is not particularly limited, but the ratio of epoxy group / phenolic hydroxyl group is preferably 0.7 to 1.5, more preferably 0.9 to 1.2, More preferably, 0.95 to 1.15 is desirable. If it deviates significantly from this range, the mold release recovery resin composition will not be sufficiently cured, and workability such as deterioration of mold release may be deteriorated.

  The curing accelerator used in the present invention is one that can be a catalyst for the crosslinking reaction between the epoxy resin and the phenol resin, and examples thereof include tributylamine, 1,8-diazabicyclo (5,4,0) undecene-7, and the like. Amine compounds, organic phosphorus compounds such as triphenylphosphine and tetraphenylphosphonium tetraphenylborate salts, and imidazole compounds such as 2-methylimidazole, but are not limited thereto. These curing accelerators may be used alone or in combination.

（式中、Ｒ_１、Ｒ_２はアミノ基、ヒドロキシル基、エポキシ基、カルボキシル基、ヒドロキシルフェニル基から選択される基であり互いに同一であっても異なっていてもよい。Ｒ_３、Ｒ_４はアルキル基、アリール基、アラルキル基から選択される有機基であり、互いに同一であっても異なっていてもよい。重量平均分子量は１３０〜１００００の正数である。） The modified organopolysiloxane which is a product obtained by reacting the organopolysiloxane represented by the general formula (1) used in the present invention with an epoxy resin or a phenol resin is an organopolysiloxane represented by the general formula (1) before the reaction. Because it has a better dispersibility in the molded product than siloxane and has a function of improving the mold release property, the mold release recovery resin composition using this is an excellent metal after using the cleaning material. Exhibits mold release recovery.

(In the formula, R ₁ and R ₂ are groups selected from an amino group, a hydroxyl group, an epoxy group, a carboxyl group, and a hydroxylphenyl group, and may be the same or different from each other. R ₃ and R ₄ may be different from each other. (It is an organic group selected from an alkyl group, an aryl group, and an aralkyl group, and may be the same or different from each other. The weight average molecular weight is a positive number of 130 to 10,000.)

When the organopolysiloxane represented by the general formula (1) is used without reacting with an epoxy resin or a phenol resin, the dispersibility in the molded product becomes insufficient, and a viscosity increase occurs during molding sealing, It may cause package contamination.
R ₁ and R ₂ in the organopolysiloxane represented by the general formula (1) react with a group selected from an amino group, a hydroxyl group, an epoxy group, a carboxyl group, and a hydroxylphenyl group, that is, an epoxy resin or a phenol resin. Functional group to be obtained, which may be the same or different. R ₃ and R ₄ are organic groups selected from an alkyl group, an aryl group, and an aralkyl group, and may be the same as or different from each other. The weight average molecular weight is a positive number from 130 to 10,000. If it falls below the lower limit, it volatilizes during the reaction with the epoxy resin or the phenol resin and cannot sufficiently react, so that it does not have a releasing effect. When the upper limit is exceeded, the viscosity of the reaction product increases, the dispersibility in the resin composition deteriorates, and it becomes easy to exude excessively on the mold surface. However, it is not preferable because the semiconductor device formed immediately after the releasability of mold release has the disadvantage that oil floats and stains occur.

  Specific examples of the epoxy resin to be reacted in advance include general epoxy resins, but bisphenol F type epoxy resins, bisphenol A type epoxy resins, epoxy derivatives of 4,4'-ethylidene bisphenol, and the like are preferable. Among these, those having an epoxy equivalent of 150 to 210 and a liquid to a softening point of 100 ° C. are particularly preferable.

  Specific examples of the phenol resin to be reacted in advance include novolak resins such as phenol novolak, cresol novolak, and naphthol novolak, phenol aralkyl resins, biphenyl skeleton-containing phenol aralkyl resins, dicyclopentadiene skeleton-containing phenol resins, naphthol aralkyl resins, and bisphenol A. Examples thereof include bisphenol compounds.

  In the present invention, when the organopolysiloxane represented by the general formula (1) is chemically reacted with the epoxy resin or the phenol resin, the mixing ratio of the two is based on 1 equivalent of the organopolysiloxane represented by the general formula (1). The epoxy resin or phenol resin is preferably 1 to 10 equivalents, more preferably 1 to 6 equivalents.

  A catalyst for promoting the reaction may be used for the chemical reaction of the organopolysiloxane represented by the general formula (1) and the epoxy resin or the phenol resin. Although it does not specifically limit as a catalyst, An imidazole compound, an amino compound, and an organic phosphine compound are used. An organic phosphine compound such as triphenylphosphine is particularly preferable from the viewpoint of reliability. The reaction temperature of the organopolysiloxane represented by the general formula (1) and the epoxy resin or the phenol resin is in the range of 70 to 200 ° C, particularly preferably 100 to 180 ° C.

  The compounding quantity of the modified organopolysiloxane which is a reaction product of the organopolysiloxane represented by the general formula (1) and the epoxy resin or the phenol resin is 0.1 to 20% by weight in the total epoxy resin composition. If the value is below the lower limit, the mold release agent does not sufficiently migrate to the mold surface, and there is a possibility that the expected mold release recoverability may not be obtained. When the upper limit is exceeded, there is a problem that the mold exudes excessively and oil floating occurs in the molded semiconductor device immediately after the release of the mold.

In addition to the components (A) to (E), the mold release recovery resin composition for semiconductor encapsulation of the present invention includes a mold release agent such as carnauba wax, stearic acid, and montanic acid wax as needed. Additives such as colorants such as ring agents, antioxidants, and carbon black may be used.
The mold release recovery resin composition for semiconductor encapsulation of the present invention is obtained by mixing the raw materials sufficiently uniformly using a mixer or the like, then melt-kneading with a hot roll or kneader, etc., cooling and pulverizing. .

Examples of the present invention are shown below, but the present invention is not limited thereto. The blending ratio is parts by weight.
Example, the modified organopolysiloxane 1-4 and organopolysiloxane 1-2 used in Comparative Example, R ₁ to R 4 in the general formula _(1), the weight average molecular weight, the reactive resin and mole basis blending ratio, Table 1 is shown collectively.

実施例１
オルソクレゾールノボラック型エポキシ樹脂（軟化点６５℃、エポキシ当量２０９）
２０．２重量部
フェノールノボラック樹脂（軟化点９０℃、水酸基当量１０４） １０．０重量部
１，８−ジアザビシクロ（５，４，０）ウンデセン−７（以下、ＤＢＵという）
０．２重量部
溶融球状シリカ（平均粒径２１μｍ） ６７．０重量部
変性オルガノポリシロキサン１ ２．０重量部
カルナバワックス ０．３重量部
カーボンブラック ０．３重量部
をミキサーを用いて各成分を混合した後、表面温度が９５℃と２５℃の２軸ロールを用いて２０回混練して得られた混練物シートを冷却後粉砕した４メッシュ以下の粉砕物をタブレット化した。得られた樹脂組成物の特性を以下の方法で評価した。評価結果を表２に示す。

Example 1
Orthocresol novolac type epoxy resin (softening point 65 ° C., epoxy equivalent 209)
20.2 parts by weight Phenol novolac resin (softening point 90 ° C., hydroxyl group equivalent 104) 10.0 parts by weight 1,8-diazabicyclo (5,4,0) undecene-7 (hereinafter referred to as DBU)
0.2 parts by weight Fused spherical silica (average particle size 21 μm) 67.0 parts by weight Modified organopolysiloxane 1 2.0 parts by weight Carnauba wax 0.3 parts by weight Carbon black 0.3 parts by weight using a mixer After mixing, the kneaded material sheet obtained by kneading 20 times using a biaxial roll having surface temperatures of 95 ° C. and 25 ° C. was cooled and then pulverized with a mesh size of 4 mesh or less. The characteristics of the obtained resin composition were evaluated by the following methods. The evaluation results are shown in Table 2.

Evaluation Method Mold Release Recovery: Using a melamine resin-based cleaning material (EMEC3, manufactured by Sumitomo Bakelite Co., Ltd.) for cleaning the mold surface, the molded product was molded three times with a mold for load release evaluation. After removing the mold release agent component on the surface of the mold, the mold release recovery resin composition was molded three times, and the mold temperature was 175 ° C., the injection pressure was 6.9 MPa, and the curing time was 2 minutes. The material for evaluation was transfer molded, and the release load at the time of product extraction was measured. The unit is MPa. The judgment criteria were 30 MPa or higher as rejected and 30 MPa or lower as acceptable. The mold for load release evaluation consists of an upper mold, a middle mold, and a lower mold. After molding, a 14 mm diameter and 1.5 mm thick circular molded product is attached to the middle mold, and a push-pull gauge from the upper hole of the middle mold And the load applied when the molded product was protruded was measured. As an evaluation material, Sumitomo Bakelite Co., Ltd., epoxy resin molding material EME-7351 for semiconductor encapsulation was used.

  Mold release sustainability: Using a melamine resin-based cleaning material (EMEC3, manufactured by Sumitomo Bakelite Co., Ltd.) for cleaning the mold surface, the molded product was molded three times with a mold for load release evaluation, After removing the mold release agent component on the mold surface, the mold release recovery resin composition was molded three times, and then the evaluation material was obtained at a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 2 minutes. Transfer molding was performed, and the mold release load at the time of product extraction was measured. The mold release load is molded using a mold for load evaluation at the time of mold release composed of an upper mold, a middle mold, and a lower mold, and after molding, the medium mold is formed into a circular molded product having a diameter of 14 mm and a thickness of 1.5 mm. A push bull gauge was applied from the upper hole of the slab, and the load applied when the molded product was projected. Subsequently, 200 shots of the evaluation material were molded, and the change in the release load for each shot was measured. At this time, the number of shots when the load was 80 MPa or more was described in the results. 200 <means 200 shots or more, and expresses that the load is 80 MPa or less even after 200 shots. The judgment criteria were less than 150 shots as unacceptable and 150 shots or more as acceptable.

  Molded product stain: Immediately after the use of the mold release recovery resin composition, the oil floating on the molded product surface of the molded evaluation material was visually confirmed. The case where the product surface was stained was expressed as “X”, and the case where the product surface was not stained was expressed as “◯”.

Examples 2-9, Comparative Examples 1-5
Using the modified organopolysiloxane and organopolysiloxane shown in Table 1, a resin composition was prepared in the same manner as in Example 1 in accordance with the formulations in Tables 2, 3, and 4, and evaluated in the same manner as in Example 1. did. The results are shown in Table 2, Table 3, and Table 4. The biphenyl type epoxy resin (YX-4000 manufactured by Japan Epoxy Resin Co., Ltd.) used in Example 2 has a melting point of 105 ° C. and an epoxy equivalent of 195. The phenol aralkyl resin (Mitsui Chemicals, XL-225) used in Example 2 has a softening point of 79 ° C. and a hydroxyl group equivalent of 174. In Example 3, montanic acid wax was used as a release agent.

  The mold release recovery resin composition for semiconductor encapsulation of the present invention can recover the mold release property by molding a few times, and oil is applied to the surface of the semiconductor device in the semiconductor seal molding immediately after the mold release recovery. It is industrially useful because it contributes to the improvement of productivity in the manufacture of semiconductor devices, because it can maintain a good release property for a long time without causing floating and dirt.

Claims (1)

In the method of manufacturing a resin-encapsulated semiconductor device in which a semiconductor element is molded and sealed using a resin composition for semiconductor encapsulation, a step of molding using a cleaning material for cleaning the surface of the mold for semiconductor encapsulation, A step of recovering mold releasability of a molding die using a mold release recovery resin composition for semiconductor sealing, and a step of continuously molding using the resin composition for semiconductor sealing. The mold release recovery resin composition for a stopper is (A) an epoxy resin, (B) a phenol resin, (C) a curing accelerator, (D) an inorganic filler, (E) an organopolyester represented by the general formula (1) A modified organopolysiloxane which is a reaction product of siloxane and an epoxy resin or a phenol resin is an essential component, and the modified epoxy resin (E) is contained in an amount of 0.1 to 20% by weight in the total epoxy resin composition. Method for manufacturing a resin-sealed semiconductor device according to claim Rukoto.

(In the formula, R ₁ and R ₂ are groups selected from an amino group, a hydroxyl group, an epoxy group, a carboxyl group, and a hydroxylphenyl group, and may be the same or different from each other. R ₃ and R ₄ may be different from each other. (It is an organic group selected from an alkyl group, an aryl group, and an aralkyl group, and may be the same or different from each other. The weight average molecular weight is a positive number of 130 to 10,000.)