JP2671727C - - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-treated silica which can be suitably used as a component for imparting mechanical strength to a composite material such as a resin composition for sealing a semiconductor device. And a method for producing the same and a filler for a semiconductor encapsulating resin composition comprising the surface-treated silica. 2. Description of the Related Art Conventionally, semiconductor elements such as transistors, ICs, and LSIs are usually encapsulated in a ceramic package, a plastic package, or the like to form a semiconductor device. The ceramic package itself has heat resistance because of its constituent material itself and also has excellent resistance to penetration, so it is strong against temperature and humidity, and because of the hollow package, it has high mechanical strength and high reliability. Sealing is possible. [0003] However, the constituent materials of the ceramic package are relatively expensive,
Due to the problem of poor mass productivity, resin sealing using a plastic package has recently become mainstream. An epoxy resin composition is mainly used for this resin sealing because of its excellent properties. However, with the technological innovation in the semiconductor field, the degree of integration of semiconductor devices has been improved, the element size has been increased, and the wiring has been miniaturized, and the packages have been becoming smaller and thinner. Improvements in reliability (low stress, moisture resistance reliability, shock resistance reliability, heat resistance reliability, crack resistance) have been demanded for stop materials. To respond to this request,
It has been studied to reduce the thermal stress by modifying the sealing resin with rubber, or to increase the amount of the inorganic filler.However, there are few that give sufficient reliability to the composite material. There is a strong demand for the development of a technology that can improve the reliability in order to cope with an increase in size. The present invention has been made in view of the above circumstances, and provides a surface silica which can be suitably used as an inorganic filler to be incorporated in a composite material such as a resin composition for encapsulating a semiconductor device, and a method for obtaining the surface-treated silica. It is intended to provide a manufacturing method. Means for Solving the Problems and Action The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that a silane coupling having at least one functional group other than a vinyl group. An organic compound having at least one functional group capable of reacting with the functional group by coating the surface of the silica particle with the silane coupling agent by mixing and stirring the agent and silica, and coating the silica particle coated with the silane coupling agent with the functional group. (
However, except for the silane coupling agent having an alkoxysilyl group) , the mixture is stirred and further reacted with the functional group of the silane coupling agent and the functional group of the organic compound. By coating with silica, it is possible to obtain silica having desired properties, and when this surface-treated silica is blended as an inorganic filler in a composite material such as an epoxy resin composition for semiconductor encapsulation, the inorganic filler may be used. Since the affinity between certain silica and the resin matrix is strengthened, it is possible to obtain a cured product with low stress and excellent impact resistance, moisture resistance, and crack resistance, especially when the resin composition for semiconductor encapsulation is filled. The inventors have found that they are very useful as agents, and have accomplished the present invention. [0006] Hereinafter, when describing the present invention in more detail, the surface-treated silica of the present invention, a vinyl group
The surface of the silica particles is coated with a silane coupling agent having at least one functional group other than the above, and further an organic compound having at least one functional group capable of reacting with the above functional group (however,
Excluding silane coupling agents having alkoxysilyl groups)
It is coated with the above organic compound by reacting with the functional group of the coupling agent . Here, the type and shape of the silica to be surface-treated are not particularly limited, and specific examples thereof include fused silica and crystalline silica. The particle size is also not limited, but when used as a filler of the resin composition for semiconductor encapsulation, the average particle size is 5 to 5.
70 μm is preferred. As the silane coupling agent having at least one functional group other than a vinyl group used for coupling of the silica, known ones can be used. Illustrative examples include γ-glycidoxypropyltrimethoxysilane and γ-glycol. Sidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-β- (aminoethyl) γ-aminopropyltrimethoxysilane, N-β-
(Aminoethyl) γ-aminopropylmethyldiethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane , trimethoxysilylpropylnadic anhydride, etc. Is mentioned. On the other hand, examples of the organic compound having at least one functional group capable of reacting with the functional group of the silane coupling agent include those having the following functional groups, but the functional groups are not limited thereto. is not. [0010] The organic compound having one or more functional groups includes an alkoxysilyl group
Other than the silane coupling agents having the following, the following are exemplified, and one of these can be used alone or in combination of two or more. Embedded image In order to obtain the surface-treated silica of the present invention, first, the above-mentioned silane coupling agent having one or more functional groups and silica are mixed and stirred, and the surface of the silica particles is coated with the above-mentioned silane coupling agent. . In this case, the compounding amount of the silane coupling is silica 10
It is preferably 0.01 to 10 parts, particularly preferably 0.1 to 2 parts with respect to 0 parts (parts by weight, hereinafter the same). When the silica and the silane coupling agent are mixed and agitated, an appropriate mixture before the mixing and agitation with the silane coupling agent is used in order to strengthen the bond between the silane coupling agent and the silanol group present on the silica surface. It is preferable to heat at a temperature for a long time or heat-treat at a high temperature. In this case, the thermoforming temperature is preferably 20 to 50 ° C. for 10 to 50 hours, and the heat treatment is preferably performed at 50 to 200 ° C. for 1 to 8 hours. The coating treatment may be carried out in a solvent-free system (dry treatment), in a solvent (wet treatment), or in a solvent after treatment in a solvent-free system. Most preferably, the reaction is carried out in a solvent such as alcohol, toluene and the like. In addition,
In the dry treatment, surface treatment is performed using a high-speed stirrer such as Henschel, and in the wet treatment, a solvent and silica are put in a container such as a flask, and a coupling agent is added while stirring and surface treatment is performed. In this coating treatment, the silica was kept at 70 to 130 ° C., and the silane coupling agent was added while stirring with a stirrer.
A method such as stirring for up to 5 hours can be employed. In this case, it is preferable to use a catalyst such as diazabicycloundecene. The surface of the silica particles whose surface is thus coated with the silane coupling agent is further reacted and coated with an organic compound having at least one functional group capable of reacting with the functional group of the silane coupling agent. Preferably, a method in which the organic compound is added while the temperature is preferably maintained at 25 to 120 ° C., and stirring is continued for 1 to 10 hours can be employed. Also in this case, it is preferable to use a catalyst such as diazabicycloundecene as in the case of mixing with the silane coupling agent. The ratio of the silane coupling agent to the organic compound is 0.01 ≦ B / A ≦ 2, where A is the equivalent of the silane coupling agent and B is the equivalent of the organic compound.
It is particularly preferable that 0.04 ≦ B / A ≦ 1.2. If this value is less than 0.01, the effect of the organic compound may not be exhibited due to the large number of functional groups of the silane coupling agent remaining unreacted. If it exceeds 2, the unreacted organic compound may remain. Therefore, when the surface-treated silica is mixed in the composite material, the resin component may be adversely affected. After the organic solvent is distilled off under reduced pressure from the reaction product treated with the silane coupling agent and the organic compound as described above, the target surface-treated silica can be obtained by drying the organic solvent. . When the surface-treated silica of the present invention is blended with various resin compositions such as conventionally known molding materials and sealing materials, and cured, the composition has low stress, impact resistance, and moisture resistance. A cured product having excellent heat resistance and crack resistance can be provided. Therefore, the surface-treated silica of the present invention is suitably used as a filler for a resin composition for encapsulating a semiconductor. In this case, the amount of the surface-treated silica is 100 to 45 parts per 100 parts of the resin.
It is preferably 0 parts. When the surface-treated silica of the present invention is used as a filler for a composite material, the other components of the composition may have the same composition as a conventionally known composite material component. EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. Example 1 3 kg of silica (average particle size: 30 μm) and 2 kg of toluene as a solvent were placed in a 5-liter four-necked flask equipped with a reflux condenser, a stirrer, and a dropping funnel, and azeotroped for 2 hours. After the dehydration, 20 g of 15 g of an epoxy group-containing silane coupling agent (γ-glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd., KBM403) was added at a temperature of 112 ° C. with a dropping funnel while stirring with a stirrer.
After stirring at the same temperature for 3 hours, 7 g of paraaminophenol was added at the same temperature while stirring was continued, and the stirring was further continued at the same temperature for 3 hours. After the solvent was distilled off from the thus obtained reaction product under reduced pressure, it was dried at 150 ° C. for 4 hours to obtain 3 kg of surface-treated silica. This surface-treated silica (inorganic filler) and other sealing resin components were mixed in the mixing ratio shown in Table 1, and were melt-kneaded using a buscon kneader to produce an epoxy resin composition. Using this epoxy resin composition, a test piece for glass transition temperature (4 mm in diameter)
, A test piece having a length of 15 mm), a disk having a diameter of 70 mm, and a semiconductor chip for reliability evaluation were respectively transfer-molded under the conditions of 175 ° C., 70 kg / cm ² , and a molding time of 2 minutes, and cured at 180 ° C. for 4 hours. Various molded articles for reliability evaluation test were obtained, and heat resistance, thermal shock resistance and crack resistance were evaluated by the following reliability evaluation test methods.
Table 2 shows the results. (Reliability Evaluation Test Method) The glass transition temperature was measured by increasing the temperature of a heat-resistant reliability test piece by 5 ° C. per minute by a TMA method (thermomechanical analysis method). Thermal shock resistance After each sample was heated to 180 ° C. in a thermostat, a destruction test was performed with heat using an impact tester, and evaluation was made based on the total absorbed energy until the sample was destroyed. Crack resistance Each sample was left in an atmosphere of 121 ° C. and 100% RH for 100 hours to absorb moisture, then subjected to a test of immersing in a solder bath at a temperature of 240 ° C. for 30 seconds, and evaluated by the number of generated package cracks. . Example 2 3 kg of silica (average particle size 30 μm) and an amino group-containing silane coupling agent (N-β (aminoethyl) γ-aminopropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd. After adding 15 g of KBM603) and mixing for 15 minutes, the mixture was heat-treated at 120 ° C. for 4 hours. This was transferred to a four-necked flask similar to that used in Example 1, and 1 kg of toluene and 1 kg of methyl isobutyl ketone were added as solvents, and the organic compound YX40 represented by the following formula was stirred at a temperature of 112 ° C. with a stirrer.
22.4 g of 00H (manufactured by Yuka Shell Epoxy) was added, and stirring was continued at the same temperature for 3 hours. After distilling off the solvent from the reaction product thus obtained under reduced pressure,
After drying at 120 ° C. for 4 hours, 3 kg of surface-treated silica was obtained. Embedded image The surface-treated silica thus obtained and other sealing components were mixed in the mixing ratio shown in Table 1 in the same manner as in Example 1 to produce an epoxy resin composition.
The same test piece was prepared and the same reliability evaluation test was performed. The results are also shown in Table 2. Example 3 3 kg of silica (average particle size 30 μm) and 15 g of an epoxy group-containing silane coupling agent (KBM403) were put into a Henschel mixer, mixed for 15 minutes, and then mixed with a diamine BAPPHG (2.2) represented by the following formula. -Bis [4- (4-aminophenoxy p
-Phenyl] propane) and mixed for an additional 15 minutes. The thus obtained product was dried at 120 ° C. for 4 hours to obtain 3 kg of surface silica. Embedded image The surface-treated silica thus obtained and other sealing components were mixed in the mixing ratio shown in Table 1 in the same manner as in Example 1, and a test piece similar to that in Example 1 was prepared. Was tested for reliability. The results are also shown in Table 2. Example 4 Silica (average particle size: 30 μm) 3 was placed in the same four-necked flask as used in Example 1.
Then, while stirring with a stirrer, 15 g of an acid anhydride-containing silane coupling agent represented by the following formula was dropped into the dropping funnel over a period of 20 minutes, and the mixture was further stirred at the same temperature for 3 hours Thereafter, 18.9 g of the diamine used in Example 3 was added while stirring was continued, and the mixture was further dried at 150 ° C. for 6 hours.
g was obtained. Embedded image An epoxy resin composition was produced by mixing the surface-treated silica thus obtained and other sealing components at the compounding ratios shown in Table 1 in the same manner as in Example 1 to obtain an epoxy resin composition. A similar test piece was prepared and a similar reliability evaluation test was performed. The results are also shown in Table 2. Comparative Example 1 Untreated silica and other sealing resin components were mixed in the mixing ratio shown in Table 1 in the same manner as in Example 1 to produce an epoxy resin composition. A reliability evaluation test was performed. Comparative Example 2 3 kg of silica and 2 kg of toluene were placed in a four-necked flask similar to that used in Example 1.
And subjected to azeotropic dehydration for 2 hours, and then, while stirring with a stirrer, a dropping funnel at a temperature of 112 ° C. with an epoxy group-containing silane coupling agent (KB, manufactured by Shin-Etsu Chemical Co., Ltd.)
M403) was added dropwise over 20 minutes, and the mixture was further stirred at the same temperature for 3 hours. The thus obtained surface-treated silica and other sealing components were mixed in the proportions shown in Table 1 in the same manner as in Example 1 to produce an epoxy resin composition, and the same as in Example 1. Were prepared and subjected to the same reliability evaluation test. The results are also shown in Table 2. [Table 1] [Table 2] According to the present invention, a surface-treated silica suitable as a filler for a composite material can be easily and efficiently produced. Gives cured products excellent in stress, humidity resistance, impact resistance, and heat resistance. Therefore, the silica of the present invention is useful as a filler for a resin composition for encapsulating a semiconductor.

Claims (1)

Claims: 1. The surface of a silica particle is coated with a silane coupling agent having at least one functional group other than a vinyl group , and further has at least one functional group capable of reacting with the functional group. Organic compounds (excluding silane coupling agents having an alkoxysilyl group)
C) by reacting the functional group with the functional group of the silane coupling agent.
A surface-treated silica , which is coated with the organic compound . 2. A mixture of a silane coupling agent having at least one functional group other than a vinyl group and silica and stirring to coat the surface of the silica particles with the silane coupling agent, and the silica particles are coated with the silane coupling agent. An organic compound having at least one functional group capable of reacting with the above-mentioned functional group with silica particles (however, a silane compound having an alkoxysilyl group)
(Except for the coupling agent ) and mix and stir with the functional group of the silane coupling agent.
A method for producing surface-treated silica, comprising reacting a functional group of an organic compound to coat the silica particles with the organic compound. 3. A filler for a resin composition for semiconductor encapsulation, comprising the surface-treated silica according to claim 1.