JP2003082193A - Method for manufacturing mold releasability-restoring resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a mold releasability-restoring resin composition excellent in mold releasability-restoring properties for a mold for semiconductor-sealing. SOLUTION: An epoxy resin (A), a phenolic resin (B), a curing accelerator (C), a reaction product of an oxidized α-olefin with ethanolamine and/or a reaction product of an oxidized α-olefin with an isocyanate (D1) and an inorganic filler (E) as essential ingredients are kneaded under heating, cooled and crushed to give a crushed matter having a particle size of 4 mesh or less. Other reaction product of an oxidized α-olefin with ethanolamine and/or other reaction product of an oxidized α-olefin with an isocyanate (D2) are admixed with the crushed matter to give the mold releasability-restoring resin composition. The compounding ratio is such that [(D1)+(D2)] is 0.1-3 wt.% of the whole resin composition and that [(D2)]/[(D1)+(D2)]>=25 wt.%, and the particle size of (D2) is at least 60 mesh and at most 16 mesh.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a mold release recovery resin composition for semiconductor encapsulation.

[0002]

2. Description of the Related Art In recent market trends of miniaturization, weight reduction, and high performance of electronic equipment, semiconductor elements are becoming highly integrated year by year, and surface mounting of semiconductor devices is being promoted.
The demand for epoxy resin compositions for semiconductor encapsulation is becoming more and more severe. Epoxy resin compositions for semiconductor encapsulation, which use various resins and additives that meet this requirement, are susceptible to mold defects during continuous molding, resulting in mold defects such as mold removal and unfilling. Therefore, it has become common to regularly clean the mold surface.

Conventionally, a cleaning material for a semiconductor encapsulation mold is composed of a resin having a high molding shrinkage ratio such as an amino resin and a filler having a high hardness such as crystal crushed silica and glass fiber. It was mainly used to scrape off the dirt on the surface of the mold. After using the cleaning material, the mold surface becomes clean, but the mold release agent on the mold surface is also removed, so that the semiconductor device molded immediately after cleaning has extremely poor mold releasability. There was a problem. Therefore, after the cleaning material is used, it is necessary to recover the mold releasability by using the mold release recovery resin composition to transfer and apply the mold release agent in the mold release recovery resin composition to the mold surface. is there.

The function of the mold release recovery resin composition is to transfer the mold release agent to the surface of the mold and apply it to quickly recover the mold release property. However, it is necessary to transfer a large amount of the mold release agent. If you do,
There is a problem of oil floating and dirt on the surface of the molded semiconductor device after that, and if the release agent cannot be transferred sufficiently, the releasability cannot be recovered, and it is necessary to use a large amount of mold release recovery resin composition. There is a problem that there is. Furthermore, when the mold releasability after recovery of the mold releasability cannot be maintained for a long time, it is necessary to frequently use the mold releasability recovery resin composition and the productivity is lowered. There is a demand for a mold release recovery resin composition for semiconductor encapsulation which is excellent in mold recovery.

[0005]

DISCLOSURE OF THE INVENTION The present invention is a mold release recovery resin composition obtained by a specific production method, wherein the resin composition recovers the mold releasability even in a small amount, and the mold releasability is improved. It is intended to provide a method for producing a mold release recovery resin composition for semiconductor encapsulation, which does not cause oil floating or stains on the surface of a semiconductor device immediately after recovery and can maintain mold releasability for a long time.

[0006]

The present invention provides [1] (A)
Epoxy resin, (B) phenol resin, (C) curing accelerator, (D1) reaction product of oxidized alpha-olefin and ethanolamine and / or reaction product of oxidized alpha-olefin and isocyanate, and (E) inorganic filler. After making each component an essential component and kneading and cooling the mixture into a pulverized product of 4 mesh or less, (D2) a reaction product of an oxidized alpha olefin and ethanolamine and / or a reaction product of an oxidized alpha olefin and an isocyanate is added to the pulverized product. A mold release recovery resin composition obtained by addition and mixing, wherein the compounding ratio [(D1) + (D2)] is 0.
1-3% by weight, [(D2)] / [(D1) + (D2)]
≧ 25% by weight, the particle size of (D2) is 60 mesh or more 1
A method for producing a mold release recovery resin composition for semiconductor encapsulation, which is 6 mesh or less, [2] The semiconductor according to item [1], wherein the carbon number of the alpha-olefin oxide is 20 to 70. Method for producing mold release recovery resin composition for sealing,
Is.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin used in the present invention is not particularly limited, but examples thereof include phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, bisphenol type epoxy resin, stilbene type epoxy resin. Epoxy resin, triphenol methane 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, and the like. These may be used alone or in combination.

The phenol resin used in the present invention is not particularly limited, but examples thereof include phenol novolac resin, cresol novolac resin, naphthol aralkyl resin, triphenol methane resin, terpene modified phenol resin and dicyclopentadiene modified phenol. Examples of the resin include phenol aralkyl resin having a phenylene and / or diphenylene skeleton, and these may be used alone or in combination. The mixing ratio of the epoxy resin and the phenol resin is not particularly limited, but as the epoxy group / ferunol hydroxyl group ratio,
0.9 to 1.2 is preferable, and 0.95 is more preferable.
1.15 is desirable. If it deviates significantly from this range, the resin composition may not be sufficiently cured and workability may be deteriorated, such as a decrease in releasability.

The curing accelerator used in the present invention includes:
Refers to those that can serve as a catalyst for the crosslinking reaction between the epoxy resin and the phenol resin, such as tributylamine, 1,
Examples include amine compounds such as 8-diazabicyclo (5,4,0) undecene-7, organic phosphorus compounds such as triphenylphosphine, tetraphenylphosphonium / tetraphenylborate salts, and imidazole compounds such as 2-methylimidazole. However, it is not limited thereto. These curing accelerators may be used alone or in combination.

The reaction product of an alpha-olefin oxide and ethanolamine used in the present invention or a reaction product of an isocyanate is an alpha-olefin oxide having a carboxyl group or a hydroxyl group obtained by oxidizing an alpha-olefin obtained from a petroleum fraction and ethanol. Obtained by reacting with an amine or isocyanate. Generally, alpha olefins have poor compatibility with epoxy resin and phenol resin components, the viscosity of the mold release recovery resin composition increases, and further exudate on the mold surface during molding, and the mold release recovery effect. However, there is a drawback in that the semiconductor device molded immediately after the release property is recovered has oil floating and dirt. Therefore, by using alpha olefin oxide, it is possible to prevent oil floating and stains on the semiconductor device due to the appropriate compatibility with the epoxy resin and phenol resin components, and to impart more fluidity, and to achieve excellent mold release recovery. However, if the mold after recovery from mold release is left at a high temperature for a long time, there is a drawback that a part of the oxidized alpha olefin is thermally decomposed and the mold releasability is deteriorated to lower the mold releasability. When the reaction product of the oxidized alpha-olefin of the present invention and ethanolamine or the reaction product of isocyanate can be used to suppress thermal decomposition at high temperature, even after leaving the mold after recovery from mold release for a long time at high temperature, It has the feature that excellent releasability can be maintained. The carbon number of the oxidized alpha olefin used in the present invention is 20 to 20.
70, more preferably 40 to 60 is desirable. When the carbon number is less than 20, the melting point is too low and the compatibility with the epoxy resin or phenol resin component is excellent, but a sufficient releasing effect may not be exhibited. Further, when it exceeds 70, the releasing effect is exhibited, but the viscosity of the releasing resin composition is increased and the compatibility with the epoxy resin or the phenol resin component is extremely lowered, and the molding is performed immediately after the releasing property is recovered. There is a possibility that oil will float or stain the formed semiconductor device. The carbon number of the oxidized alpha olefin used in the present invention refers to all carbons in the molecule.

The rate of amination of the reaction product of the oxidized alpha olefin and ethanolamine or urethanization of the reaction product of the oxidized alpha olefin and isocyanate is not particularly limited, but the nitrogen content in the obtained release agent is not limited. As for, the content of 0.3 to 5% by weight is desirable. If there are too many amination or urethanization moieties, the viscosity of the release agent itself may increase and it may be difficult to materialize it, which is not preferable.
The ethanolamine reaction product is obtained by reacting a hydroxyl group or a carboxyl group of an oxidized alpha olefin with ethanolamine to obtain an amine. It can be obtained by reacting with other compounds to form urethane. The reaction product of the oxidized alpha olefin and ethanolamine and the reaction product of the oxidized alpha olefin and isocyanate may be used alone or in combination. These are commercially available from Toyo Petrolite Co., Ltd. and can be easily obtained from the market.

The amount of the reaction product of the oxidized alpha olefin and ethanolamine and / or the reaction product of the isocyanate used in the present invention is 0.1 to 0.1% based on the total resin composition.
It is preferably 3% by weight, more preferably 0.5 to 2% by weight. If it exceeds 3% by weight, it will exude into the mold excessively,
There is a problem that oil floating occurs in the semiconductor device immediately after the release is recovered. On the other hand, if the amount is less than 0.1% by weight, the release agent may not sufficiently migrate to the surface of the mold, and the expected mold release recovery may not be obtained. In the method for producing a mold release recovery resin composition of the present invention, a release agent (D1) added in the first half of the production process and a release agent (D2) added in the second half of the production process.
[(D1) + (D2)] is 0.1 to 3% by weight in the total resin composition, and the compounding ratio [(D2)] /
[(D1) + (D2)] ≧ 25 wt%, (D2)
The grain size is 60 mesh or more and 16 mesh or less.

When the particle size of (D2) is smaller than 60 mesh, a part of the releasing agent melted by the heat at the time of molding becomes compatible with the resin component, and the exudation on the surface of the mold is reduced, which is sufficient. The effect of recovering releasability of the mold is not exhibited, and the compounding amount of the resin composition for recovering the mold releasability becomes large, resulting in a decrease in productivity. Again 16
When the particle size is larger than that of the mesh, there is a problem that the excessively exuded release agent excessively transfers to the mold, causing oil floating and dirt on the semiconductor device. [(D2)] / [(D
1) + (D2)] is less than 25% by weight, the releasing property of the mold release recovery resin composition itself is sufficient, but the amount of the releasing agent that migrates to the surface of the mold and can be applied is small, which is sufficient. No release effect can be obtained.

As the inorganic filler used in the present invention,
Although not particularly limited, it is generally used for a sealing material, and examples thereof include fused crushed silica, fused spherical silica, crystalline silica, and the like, and fused spherical silica is particularly preferable. The shape is not limited to a perfect sphere, and the filling amount can be increased by mixing particles having different particle sizes. These may be used alone or in combination.

The mold release recovery resin composition of the present invention comprises
In addition to the components (A) to (E), additives such as a release agent such as carnauba wax, stearic acid, montanic acid wax, a coupling agent, and a coloring agent such as carbon black may be used, if necessary. . The mold release recovery resin composition of the present invention comprises (A) epoxy resin, (B) phenol resin,
(C) A curing accelerator, (D1) a reaction product of an oxidized alpha olefin and ethanolamine and / or a reaction product of an oxidized alpha olefin and an isocyanate, and (E) an inorganic filler are mixed using a mixer or the like, and then heated. The mixture is heated and kneaded by using a kneader, a heat roll, an extruder, etc., and then cooled and pulverized into a pulverized product having a size of 4 mesh or less.
2) It is obtained by adding and mixing a reaction product of an ethanolamine of an oxidized alpha olefin and / or an oxidized alpha olefin and an isocyanate having a particle size of 16 mesh or less, and then tabulating the mixture. If the mixing method is such that heat is generated when the pulverized product of 4 mesh or less and 60 mesh or more and 16 mesh or less (D2) are mixed, (D2) is melted and the epoxy resin and the phenol resin component become compatible with each other, and gold As a mold release recovery resin composition, the release agent is not sufficiently transferred to the surface of the mold at the time of use and cannot be applied, and a sufficient release recovery effect cannot be exhibited, which is not preferable.

[0016]

EXAMPLES The present invention will be specifically described below with reference to examples.
The mixing ratio is parts by weight. Example 1 Orthocresol novolac type epoxy resin (softening point 65 ° C., epoxy equivalent of 200) 21.4 parts by weight Phenol novolac resin (softening point 80 ° C., hydroxyl equivalent of 104) 10.1 parts by weight 1,8-diazabicyclo (5,5) 4,0) Undecene-7 (hereinafter referred to as DBU) 0.2 parts by weight Spherical fused silica 65.6 parts by weight Release agent 1 0.4 parts by weight Release agent 2 0.2 parts by weight Carnauba wax 0.3 parts by weight After mixing 0.3 parts by weight of carbon black with each component using a mixer, the surface temperature was 9
The release agent 1 was added to 98.5 parts by weight of a pulverized product (composition) of 4 mesh or less obtained by pulverizing after cooling a kneaded product sheet obtained by kneading 20 times using biaxial rolls at 5 ° C and 25 ° C. Further 1.
After blending and mixing 5 parts by weight, tablets were formed. The release agent 1 is a mixture of a reaction product of an alpha olefin oxide (50 carbon atoms) and monoethanolamine and a reaction product of an alpha olefin oxide (50 carbon atoms) and toluene diisocyanate in a weight ratio of 1: 1 (melting point). 75 ° C, acid value 2, saponification value 3
0) is adjusted to a particle size of 32 mesh or more and 16 mesh or less, and the release agent 2 is a reaction product (melting point 90, acid value 12, saponification value 40) of oxidized alpha olefin (carbon number 50) and toluene diisocyanate. 32 mesh or more 16
The particle size is adjusted to be smaller than that of the mesh. The characteristics of the obtained mold release recovery resin composition were evaluated by the following methods.
The evaluation results are shown in Table 1.

Evaluation method Spiral flow: Using a mold for spiral flow measurement according to EMMI-1-66, mold temperature 175 ° C.
It was measured at an injection pressure of 70 kg / cm ² and a curing time of 2 minutes.
The unit is cm. Mold release recovery: A melamine resin-based cleaning material for cleaning the mold surface was used to mold a molded product with a mold for load evaluation during mold release, and the mold release agent component on the surface of the mold was removed. After molding the mold release recovery resin composition three times, transfer molding of the evaluation material was performed at a mold temperature of 175 ° C., an injection pressure of 70 kg / cm ² , and a curing time of 2 minutes, and the mold was released when the molded product was taken out. The load was measured. The unit is MPa. The mold for load evaluation during release is composed of upper mold, middle mold, and lower mold. A 14 mmΦ 1.5 mm thick circular molded product adhered to the middle mold after molding is pushed through the hole in the upper part of the middle mold to push bull gauge. Was applied, and the load applied when the molded product was projected was measured. As an evaluation material, an epoxy molding material EME-7351 manufactured by Sumitomo Bakelite Co., Ltd. for semiconductor encapsulation was used. Mold release sustainability: Mold the molded product with a mold for load evaluation during mold release,
After removing the release agent component on the surface of the mold, the mold release recovery resin composition is molded three times, and the mold temperature is 175 ° C.
The evaluation material was transfer-molded at an injection pressure of 70 kg / cm ² and a curing time of 2 minutes, and the initial mold release load when the molded product was taken out was measured. As for the mold release load, a mold for load evaluation at the time of mold release consisting of an upper mold, a middle mold and a lower mold is used for molding, and after molding, a circular molded product of 14 mmΦ and 1.5 mm thick is attached to the middle mold. A push bull gauge was applied from the hole on the top, and the load was applied when the molded product was ejected. Subsequently, the evaluation material was molded for 200 shots, and the change of the mold release load for each shot was measured. At this time, it was expressed by the number of shots in which the mold release load increased by 30% or more with respect to the initial mold release load. 200 <expresses that the release load is 200% or more and 30% or less of the initial release load. Mold release maintainability: Molded products are molded with a mold for load evaluation during mold release,
After removing the release agent component on the surface of the mold, the mold release recovery resin composition is molded three times, and the mold temperature is 175 ° C.
The material for evaluation was transfer-molded at an injection pressure of 70 kg / cm ² and a curing time of 2 minutes, and the initial mold release load when the molded product was taken out was measured. As for the mold release load, a mold for load evaluation at the time of mold release consisting of an upper mold, a middle mold and a lower mold is used for molding, and after molding, a circular molded product of 14 mmΦ and 1.5 mm thick is attached to the middle mold. Apply the push bull gauge from the hole on the top,
The load applied when the molded product was projected. Then, after leaving the mold heated at 175 ° C. for 24 hours, the mold release load was measured again in the same manner, and the increase ratio of the mold release load to the initial value was expressed in%. Product stain: The oil release and stain condition on the surface of the molded product of the evaluation material molded immediately after the mold release recovery resin composition was used were confirmed. When the surface was wiped, those that could be wiped off were judged to be oily, and those that could not be removed were judged to be stains. When the product surface had stains, it was expressed as ×, when there was no stain but oil was floating, it was expressed as Δ, and when there was neither, it was expressed as ○.

Examples 2 to 5 and Comparative Examples 1 to 6 According to the formulations shown in Tables 1 and 2, the same mold release recovery resin composition as in Example 1 was obtained. The biphenyl type epoxy resin (YX-4000 manufactured by Japan Epoxy Resin Co., Ltd.) used in Examples 4 and 5 and Comparative Examples 4 to 6 has a melting point of 105 ° C. and an epoxy equivalent of 195. Phenol aralkyl resin used in Examples 4 and 5 and Comparative Examples 4 to 6 (manufactured by Mitsui Chemicals, Inc.,
XL-225) has a softening point of 79 ° C. and a hydroxyl equivalent of 174. The microcrystalline waxes of Comparative Examples 1 and 4 have a melting point of 90 ° C. The polyethylene waxes of Comparative Examples 1 and 2 have a melting point of 92 ° C. The melting point of the oxidized polyethylene wax of Comparative Example 3 is 92 ° C. The particle sizes of the microcrystalline wax, polyethylene wax, and oxidized polyethylene wax are all adjusted to 32 mesh or more and 16 mesh or less.

[0019]

[Table 1]

[0020]

[Table 2]

[0021]

[Effects of the Invention] After using the mold release recovery resin composition for semiconductor encapsulation obtained by the production method of the present invention, the molded semiconductor device has no oil floating or dirt, and has a good mold release recovery property. It is excellent and can maintain mold releasability for a long time, which contributes to productivity improvement and is industrially useful.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08K 5/00 C08K 5/00 5F06 H01L 21/56 H01L 21/56 T 23/29 23/30 R 23 / 31F Term (Reference) 4F070 AA46 AC04 AC23 AC45 AC47 AC84 AC86 AC94 AE01 AE08 DA45 DC07 DC11 FA03 FA07 FA17 FB07 4F202 AA39 AH33 AM13 CA12 CB12 CS02 4J002 CC04X CC05X CD03W CD04W CD06W EU070 CD0W26O0E0X0 EN26W0E0XEN026E0XEN0X26EN0E0XEN0W026W0E0X0EN0W026W0E0X0EN0W0E0X0EN0W0E0X0W0 FD018 FD14X FD156 FD160 FD167 GJ02 GQ00 HA09 4J036 AA01 DA02 FA01 FA12 FB07 JA07 KA05 4M109 AA01 CA21 EA02 EB03 EB04 EB06 EB08 EB09 EB13 EB18 GA10 5F061 CA21 DA01 DC01

Claims (2)

[Claims] 1. (A) Epoxy resin, (B) Phenolic resin, (C) Curing accelerator, (D1) Reaction product of oxidized alpha-olefin and ethanolamine and / or reaction product of oxidized alpha-olefin and isocyanate, And (E)
An inorganic filler is used as an essential component, and each of the above components is heated, kneaded, and cooled into a pulverized product having a size of 4 mesh or less.
A mold release recovery resin composition obtained by adding and mixing a reaction product of an oxidized alpha olefin and ethanolamine and / or a reaction product of an oxidized alpha olefin and an isocyanate, wherein the compounding ratio [(D1) + ( D2)] is 0.1 to 3% by weight in the total resin composition, and [(D2)] /
[(D1) + (D2)] ≧ 25% by weight, and the particle size of (D2) is 60 mesh or more and 16 mesh or less, a method for producing a mold release recovery resin composition for semiconductor encapsulation. 2. The carbon number of the oxidized alpha olefin is 2.
It is 0-70, The manufacturing method of the mold release recovery resin composition for semiconductor sealing of Claim 1.