JP2626377B2 - Epoxy resin composition and semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition and a semiconductor device particularly suitable for sealing a semiconductor device.

[0002]

2. Description of the Related Art Epoxy resin molding materials are generally superior to other thermosetting resins in electrical properties, mechanical properties, adhesion, moisture resistance, etc., and have sufficient fluidity even at low pressure during molding. Since it has properties such as not deforming or damaging the insert, IC, LSI, diode,
It is widely used for sealing and impregnating electronic components such as transistors and resistors.

Conventionally, typical curing agents for this epoxy resin molding material include acid anhydrides, aromatic amines, and novolak-type phenol resins. Among these, epoxy resins using novolak-type phenol resins as curing agents are among them. Resin molding materials have the characteristics that they are the best in terms of moisture resistance, reliability, moldability, etc., and are non-toxic and inexpensive compared to epoxy resin molding materials using other curing agents. Therefore, it is widely used as a resin sealing material for semiconductor devices such as ICs, LSIs, diodes, and transistors.

However, an epoxy resin molding material using a novolak type phenolic resin as a curing agent has poor electrical characteristics at high temperatures. Therefore, when an MOS type semiconductor device whose operating temperature is 80 ° C. or higher is sealed using the epoxy resin molding material, In this sealing device, if a leak current flows between the electrodes and it does not show normal semiconductor characteristics, or if the IC is sealed with resin and subjected to a deterioration test under high temperature and high humidity, it can be used for chip wiring. Aluminum wires are corroded in a short time, resulting in disconnection.

For this reason, not only the epoxy resin and the curing agent that constitute the epoxy resin composition, but also various other components have been studied in various ways. An epoxy resin composition using an organic phosphine compound as a curing accelerator has been developed. Epoxy resins for semiconductor encapsulation, for example, because the humidity resistance at high temperature and high humidity and the electrical characteristics at high temperature are improved as compared with the case of using a catalyst such as imidazole and tertiary amine. Although it is often used as a component of the composition, an epoxy resin composition having more excellent moisture resistance and high-temperature electrical properties is desired.

[0006] In view of the above circumstances, the present applicant has previously disclosed in Japanese Patent Publication No. 63-25010 an epoxy resin composition containing an epoxy resin, a phenol resin as a curing agent, a curing accelerator, and an inorganic filler. In the product, a cresol novolak epoxy resin having an organic acid content of 100 ppm or less as an epoxy resin, a chlorine ion content of 2 ppm or less, a hydrolyzable chlorine content of 500 ppm or less, and an epoxy equivalent of 180 to 230, A novolak type phenol resin having a softening point of 80 to 120 ° C., an organic acid content of 100 ppm or less, free Na and Cl of 2 ppm or less, and free phenol of 1% or less is used as the phenol resin. The molar ratio of the epoxy group (a) to the phenolic hydroxyl group (b) of the phenol resin ( / B) is adjusted to the range of 0.8 to 1.5, and a tertiary compound having at least one functional group selected from a carboxyl group, a methylol group, an alkoxy group, and a hydroxyl group in the molecule as a curing accelerator. An organic phosphine compound, specifically a compound represented by the following formula (I), is prepared by adding the epoxy resin and the phenol resin in a total amount of 10%.
An epoxy resin composition characterized by using 0.4 to 5 parts by weight per 0 parts by weight has been proposed.

[0007]

Embedded image (Wherein, R ^{1 to} R ⁵ are each constituted by any of a hydrogen atom, a carboxyl group, a methylol group, an alkoxy group, and a hydroxyl group, and at least one of R ^{1 to} R ⁵
The individual is selected from a carboxyl group, a methylol group, an alkoxy group, and a hydroxyl group, and n is an integer of 1 to 3. )

The epoxy resin composition has curing properties,
Electrical properties at high temperature, heat resistance (high glass transition temperature Tg),
It has excellent moisture resistance properties, and as a result, it does not corrode and break even when left for a long time under high temperature and high humidity, and has excellent molding workability and long-term storage stability. .

[0009]

However, as a result of further study of the epoxy resin composition proposed in Japanese Patent Publication No. 325010 by the present inventor, it was found that a voltage was applied to an IC molded with the epoxy resin composition. It has been found that there is a problem that the aluminum wiring often breaks when left in a high-temperature, high-humidity environment, and thus a solution to this problem has been desired.

The present invention has been made in view of the above circumstances,
Epoxy resin composition and cured product of the epoxy resin composition improved in the disadvantage that the epoxy resin composition proposed in Japanese Patent Publication No. 325010 mentioned above is inferior in moisture resistance in a state where a voltage is applied while maintaining excellent characteristics. It is an object to provide a semiconductor device sealed by the above.

[0011]

The present inventors have made intensive studies to achieve the above object, and as a result, among the components of the epoxy resin composition proposed in JP-B-63-25010, the curing acceleration As a tertiary organic phosphine compound used as an agent, a phenyl group of triphenylphosphine in which a methoxy group is introduced at the 2- and 6-positions, or a methoxy group introduced at the 4-position in addition to the 2- and 6-positions When an organic phosphorus compound represented by the following formula (1 ′) is compounded as a curing accelerator and silica powder is further compounded as an inorganic filler, a voltage is applied to the IC sealed with the epoxy resin composition. It has been found that even when exposed to high temperature and high humidity, the aluminum wiring has a remarkable effect that disconnection hardly occurs, and epoxy containing an organic phosphorus compound of the following formula (1 ′) is blended. It proposed a fat composition (JP-5-
No. 59150).

[0012]

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Subsequently, as a result of further study, two of the phenyl groups of triphenylphosphine in the above composition were
The tris (2,4,6-trimethoxyphenyl) phosphine having a methoxy group introduced at the 4-, 4- and 6-positions has the following general formula (2) A _x O _y (NO ₃ ) _z (OH) _w · h ( H ₂ O) (2) (where A represents one or more metals selected from Sb, Al and Bi, x = 1 to 5, y = 1 to 7,
z = 0 to 3, w = 0.2 to 3, and h = 0 to 2. ) Having an average particle size of 5 μm or less and a maximum particle size of 30 μm or less, preferably 0.5% (% by weight, the same applies hereinafter) of the whole composition. The ion exchanger reliably captures free impurities such as hydrolyzable chlorine and bromine, effectively suppresses corrosion of aluminum wiring due to a cured product of the composition, has good curability of the composition, and seals the semiconductor. It has been found that an epoxy resin composition that can be suitably used as a stopper or the like can be obtained.

[0014] In this case, the following formula alkenyl groups the alkenyl group-containing epoxy resin or alkenyl group-containing phenol resin ^{_{(3) H a R 1 b}} SiO 2- (a + b) / 2 ... (3) ( where Wherein R ¹ represents a substituted or unsubstituted monovalent hydrocarbon group, and a and b represent 0.001 ≦ a ≦ 1, 1 ≦ b ≦ 3,
It is a positive number satisfying 1 ≦ a + b <4. The number of silicon atoms in one molecule is an integer of 20 to 400, and the number of hydrogen atoms directly connected to the silicon atom in one molecule is an integer of 1 or more. By mixing a silicone-modified epoxy resin or a silicone-modified phenol resin, which is a polymer to which an SiH group of an organosilicon compound represented by the formula (1) is added, the above-mentioned effects are exhibited, and furthermore, excellent low stress property is obtained. It has been found that the present invention can be realized, and the present invention has been accomplished.

Accordingly, the present invention provides (1) an epoxy resin, (2) a phenolic curing agent, (3) a curing accelerator represented by the following formula (1), (4) silica powder, and (5) (2) an epoxy resin composition comprising an inorganic ion exchanger having an average particle size of 5 μm or less and a maximum particle size of 30 μm or less as an essential component; The present invention provides an epoxy resin composition containing the above-mentioned silicone-modified epoxy resin or silicone-modified phenol resin as part or all of the component (2), and a semiconductor device sealed with a cured product thereof.

Now, the present invention will be described in further detail. The epoxy resin as the first essential component used in the epoxy resin composition of the present invention has one or more, especially two or more epoxy groups in one molecule. If there is no particular limitation,
For example, bisphenol type epoxy resin, alicyclic epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, triphenolmethane type epoxy resin, naphthalene ring-containing epoxy resin, aralkyl group-containing epoxy resin, etc. The species can be used alone or in combination of two or more.

The epoxy resin used in the present invention includes:
The organic acid content contained therein is 100 ppm or less, more preferably 20 ppm or less, chloride ion is 2 ppm or less, more preferably 1 ppm or less, and the content of hydrolyzable chlorine is 500 ppm or less, more preferably 300 pp.
m is preferably used, and if at least one of these conditions is not satisfied, the moisture resistance may decrease.

The structure of the phenolic curing agent (phenolic resin) as the second essential component is not particularly limited as long as it has two or more phenolic hydroxyl groups in one molecule. For example, phenol novolak resin, cresol Novolak resins, naphthol resins, aralkylphenol resins, triphenol resins and the like are preferably used. Like the epoxy resin, it is preferable that the free Na and Cl in the phenol resin be 2 ppm or less from the viewpoint of the moisture resistance of the semiconductor. In addition, the phenol of the monomer contained therein,
That is, if the amount of free phenol exceeds 1%, in addition to adversely affecting the above-mentioned moisture resistance, when a molded article is formed from this composition, defects such as voids, unfilled parts, sink marks and the like are easily generated in the molded article. The amount of the free phenol is preferably 1% or less. Further, it is effective that the amount of organic acid such as formic acid generated by a Cannizzaro reaction of a trace amount of formaldehyde remaining during the production of the phenol resin is also 100 ppm or less from the viewpoint of the moisture resistance of the semiconductor.

The phenol resin has a softening point of 8
If the temperature is lower than 0 ° C., Tg is lowered, and thus heat resistance may be deteriorated. If the softening point exceeds 120 ° C., the melt viscosity of the epoxy resin composition may be increased and workability may be deteriorated. Also in the case of the above, the moisture resistance may be deteriorated, so that the softening point of the phenol resin is preferably set to 80 to 120 ° C.

The more preferable range of the amount of free phenol in the phenol resin is 0.3% or less, the more preferable range of the amount of the organic acid is 30 ppm or less, and the more preferable range of the softening point of the phenol resin is 90 to 110. ° C, and the object of the present invention can be more reliably achieved by adjusting the temperature within the above range.

Further, it is preferable that the composition of the present invention contains a silicone-modified phenol resin and / or a silicone-modified epoxy resin, whereby the moisture resistance under a voltage applied state is more remarkably increased, and low linear expansion is achieved. And a composition giving a cured product having a low modulus of elasticity.

This silicone-modified phenol resin or silicone-modified epoxy resin is obtained by adding an SiH group of an organosilicon compound represented by the following general formula (2) to an alkenyl group of an alkenyl group-containing epoxy resin or an alkenyl group-containing phenol resin. Polymer.

[0023]

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In this case, as the alkenyl group-containing epoxy resin or alkenyl group-containing phenol resin, an alkenyl group-containing epoxy resin or phenol resin represented by the following formula (3) is more preferably used. The addition polymer with the organic silicon compound represented by (2) is effective.

[0025]

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In this case, the above-mentioned silicone-modified epoxy resin or phenol resin has a hydrolyzable chlorine content of 500 ppm or less, free Na and Cl ions of 2 ppm or less, and an organic acid content of 100 ppm or less. Preferably, hydrolysable chlorine, free Na, Cl
If the content of ions or organic acids exceeds the above values, the heat resistance of the sealed semiconductor device may be deteriorated.

The above silicone-modified epoxy resin or phenol resin may be used alone or as a mixture of two or more kinds. The compounding amount is 100 parts by weight of the total amount of the epoxy resin and the curing agent mixed in the composition ( It is preferably 5 to 70 parts, more preferably 8 to 50 parts per part by weight (hereinafter the same). If the blending amount of the silicone-modified epoxy resin or phenolic resin is less than 5 parts, it is difficult to obtain a sufficiently low stress property, and if it exceeds 70 parts, the mechanical strength of the molded article may decrease.

In the present invention, the epoxy resin (including the silicone-modified epoxy resin or phenol resin) and the phenol resin are used in a molar ratio between the epoxy group (a) of the epoxy resin and the phenolic hydroxyl group (b) of the phenol resin. (A / b) is set to 0.8 to 1.5, preferably 0.1 to 1.5.
It is preferable to adjust to a range of 9 to 1.5. If the molar ratio of the two groups is less than 0.8, the curing properties of the composition and the glass transition temperature (Tg) of the molded article may deteriorate, and the heat resistance may decrease. In some cases, the glass transition temperature and the electrical characteristics deteriorate.

Next, the composition of the present invention comprises a tris (2,4,6-) represented by the following general formula (1) as a curing accelerator.
(Trimethoxyphenyl) phosphine is used.

[0030]

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That is, the present invention uses tris (trimethoxyphenyl) phosphine in which a methoxy group is introduced at the 2-, 4-, and 6-positions of triphenylphosphine as a curing accelerator. Triphenylphosphine in which a methoxy group has not been introduced or triphenylphosphine in which a methoxy group has been introduced only at the 4-position cannot achieve the object of the present invention as will be shown in Examples described later.

The amount of the tris (trimethoxyphenyl) phosphine compounded is such that the epoxy resin as the first component and the phenolic curing agent (phenol resin) as the second component
The total amount is preferably from 0.4 to 5 parts, more preferably from 0.8 to 2 parts, per 100 parts of the total amount, and an excellent effect for the purpose of the present invention is exhibited at this compounding amount. However, when the compounding amount of the organic phosphine compound according to the present invention is out of the above range, it is difficult to obtain desired physical properties. That is,
If the amount is too small, the curability is poor. If the amount is too large, the storage stability, the electrical properties at high temperatures, and the moisture resistance of the composition may deteriorate.

In the present invention, in addition to the above-mentioned tris (trimethoxyphenyl) phosphine, other curing accelerators such as triphenylphosphine, tricyclohexylphosphine, tributylphosphine, methyldiphenylphosphine, and the like which have been conventionally used. Organic phosphine compounds such as 1,2-bis (diphenylphosphino) ethane and bis (diphenylphosphino) methane;
Tertiary amines such as diazabicyclo (5.4.0) undecene-7, imidazoles and the like may be added as long as the effects of the present invention are not impaired. In this case, in combination with 1,8-diazabicycloundecene is particularly preferred from the viewpoint of moisture resistance, and 0.0 to 1 part of the compound of the formula (1) is used.
It is preferable to use 2 to 2 parts in combination.

Further, silica powder is used as an inorganic filler in the composition of the present invention. Examples of the silica powder include fused and crystalline silica, and it is more preferable to use fused silica in order to reduce the linear expansion coefficient of the obtained cured product. In particular, in order to have a low linear expansion and a low melt viscosity of the composition, fused silica having a wide particle size distribution is used in an amount of 200 to 90 parts per 100 parts of the total amount of the epoxy resin and the phenol resin.
It is preferable to use 0 parts, especially 300 to 700 parts. The above-mentioned silica powder which has been treated with a silane coupling agent or the like can be used.

If necessary, in addition to the above-mentioned silica powder, other conventionally known inorganic fillers such as natural silica such as crystalline silica and amorphous silica, synthetic high-purity can be used as long as the object of the present invention is not impaired. Silica, synthetic spherical silica, talc, mica, silicon nitride, boron nitride, alumina and the like may be used in combination.

The composition of the present invention further comprises an inorganic ion exchanger represented by the following general formula (2): A _x O _y (NO ₃ ) _z (OH) _w · h (H ₂ O) (2) Is blended.

The inorganic ion exchanger of the formula (2) has an effect of trapping free impurity ions in the epoxy resin composition. Here, in equation (2), A is S
one or two or more metals selected from b, Al and Bi, x represents 1 to 5, y represents 1 to 7, and specific examples of AxOy include Sb ₂ O ₃ , Al ₂ O ₃ , and Bi. ₂ O _{3 and the} like can be mentioned. In addition, z indicating the number of NO ₃ groups in the formula (2) is 0 to 3, but is preferably 0.02 or more, particularly 0.02 to 0.2 from the viewpoint of the effect of trapping impurities. When z is larger than 3, the curability of the composition becomes poor. Further, in the formula (2), w is 0.2 to 3, preferably 0.5 to 1.5, h is 0 to 2, preferably 0.2.
~ 1.

Specific examples of the inorganic ion exchanger of the above formula (2)
The following are Al _TwoO_2.2(OH)_0.8・ 0.5H_TwoO Sb_TwoBi_1.2O_6.8(OH )_0.8・ 0.5H_TwoO Sb_TwoBi_1.2O_6.4(NO_Three)_0.5(OH )_0.9・ 0.5H_TwoO Sb_TwoBi_1.2O_6.8(NO_Three)_0.08(OH )_0.8・ 0.4H_TwoO 2 can be mentioned, and among these, the curing characteristics of the composition are
Good retention of properties and good trapping effect of free impurities?
Thus, the compound of the following formula (2a) is more preferably used. Sb_aBi_bO_c(NO_Three)_d(OH )_e・ FH_TwoO ... (2a) (where a and b are each 1-2, c is 4-10,
d is 0.02 to 0.2; e is 0.5 to 1.5;
It is a number of 2 to 1. )

The average particle size of the inorganic ion exchanger is preferably 5 μm or less, and particularly preferably 0.1 to 2 μm in order to enhance the effect of capturing impurity ions.

The content of the inorganic ion exchanger is preferably 0.5% or more, especially 1 to 5% of the whole composition, and if the content is less than 0.5%, trapping of impurity ions is performed. May be reduced.

The composition of the present invention may further contain various additives, if necessary, depending on the purpose and use. For example, waxes, release agents such as fatty acids such as stearic acid and metal salts thereof, pigments such as carbon black, dyes, flame retardants, surface treatment agents (such as γ-glycidoxypropyltrimethoxysilane), aging Inhibitors and other additives may be blended.

The composition of the present invention can be prepared by uniformly stirring and mixing the above-mentioned components, kneading with a roll or kneader heated to 60 to 95 ° C., cooling, and pulverizing. Obtainable. There is no particular limitation on the order of compounding the components.

The epoxy resin composition of the present invention comprises an IC, L
It is suitably used for sealing semiconductor devices such as SIs, transistors, thyristors, and diodes, and for manufacturing printed circuit boards. When the semiconductor device is sealed, a conventional molding method such as transfer molding, injection molding, and casting method can be employed. In this case, the molding temperature of the epoxy resin composition is 150 to 180 ° C., and the post cure is 150 to 1
It is preferable to carry out at 80 ° C. for 2 to 16 hours.

[0044]

EXAMPLES The present invention will be described below in detail with reference to examples and comparative examples, but the present invention is not limited to the following examples. In addition, in the following examples, a part shows a weight part.

Example 1, Comparative Examples 1-4 Cresol novolak epoxy resin having an epoxy equivalent of 196 (chlorine ion 1 ppm, hydrolyzable chlorine 300 pp)
m, organic acid content 20 ppm) 59.0 parts, softening point 10
Phenol type novolak resin at 0 ° C (organic acid content 10
ppm, Na ion, Cl ion each 1 ppm, free phenol 0.1%) 33.0 parts, brominated phenol novolak resin (Nippon Kayaku, BREN-S) 8.0
Parts, antimony trioxide 10 parts, fused silica 400 parts, carnauba wax 1 part, carbon black 1 part, γ-glycidoxypropyltrimethoxysilane 1 part, and the organic phosphorus compounds and inorganics of the type and amount shown in Table 1 After sufficiently mixing the composition to which the ion exchanger was added, the mixture was kneaded with a heating roll, then cooled and pulverized to obtain an epoxy resin composition (Example 1, Comparative Examples 1 and 2). The ratio of epoxy group / phenol group was 1.1 (molar ratio).

For these epoxy resin compositions, the secondary transition temperature Tg was measured, and the Tg when the composition was forcibly humidified to a water absorption of 0.2% by weight was calculated as Tg at the time of moisture absorption.
g. In addition, the following tests A to C were performed. The results are shown in Table 1.

A. Measurement of Volume Resistivity A test was conducted by molding at a molding temperature of 160 ° C., a molding pressure of 70 kg / cm ² , and a molding time of 2 minutes to produce a disk having a diameter of 9 cm and a thickness of 2 mm, and post-curing the same at 180 ° C. for 4 hours. The value of the piece when heated at 150 ° C is J
It measured according to IS-K6911.

B. Measurement of Humidity Resistance After the test piece obtained in the same manner as in A above was kept in steam at 120 ° C. for 500 hours, the dielectric loss tangent (1 kHz) was measured according to JIS-K6911.

C. Aluminum corrosion test 14-pin IC with aluminum wiring on chip
Was molded in a transfer molding machine, and the molded product was post-cured at 180 ° C. for 4 hours, and then placed in a test vessel at 130 ° C. and 85% RH with a voltage of 20 V applied.
After leaving for 00 hours, the disconnection of the aluminum wiring was detected to determine the defect (n = 20).

[0050]

[Table 1]

[0051]

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[Example 2, Comparative Examples 5 to 7] 42.3 parts of the following epoxy resin I, brominated phenol novolak epoxy resin (BREN manufactured by Nippon Kayaku Co., Ltd.)
-S) 8 parts, triphenolmethane (phenol equivalent:
94) 28.7 parts, 21 parts of a silicone-modified epoxy resin I shown below, an organic phosphorus compound shown in Table 2, the above-mentioned inorganic ion exchanger A, fused silica (specific surface area: 1.0 m ² /
g, spherical silica having an average particle size of 30 μm and coarse particles of 0.1% of coarse particles of 75 μm or more, a specific surface area of 3.2 m ² / g, and an average particle size of 8 μ
100 parts of a mixture of crushed silica having a coarse particle size of 75 μm or more and 0.1% coarse particles and spherical silica having a specific surface area of 10 m ² / g and an average particle size of 1.0 μm in a ratio of 70:20:10 parts is γ. Glycidoxypropyltrimethoxysilane 0.60
Part), 600 parts of Sb ₂ O ₃ , 1.5 parts of carbon black, 1 part of carnauba wax and γ
After sufficiently mixing 3 parts of glycidoxypropyltrimethoxysilane, the mixture was kneaded with a heating roll, then cooled and pulverized to obtain an epoxy resin composition. In addition, epoxy group /
The ratio of all phenol groups was 1.0 (molar ratio).

[0053]

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For these compositions, the secondary transition temperature Tg, Tg at the time of moisture absorption, volume resistivity, moisture resistance, and aluminum corrosion test were conducted in the same manner as in Example 1. The results are also shown in Table 2.

[0055]

[Table 2]

From the results in Tables 1 and 2, when triphenylphosphine, which is a conventionally used catalyst, was used (Comparative Examples 2, 4, and 6 in both tables), not only the initial Tg was low, but also the initial Tg was low. Tg at the time of moisture absorption is greatly reduced, and heat resistance is poor. In addition, tris (4-
When (methoxyphenyl) phosphine is used (Comparative Examples 1 and 3 in both tables), a defect is very likely to occur in the corrosiveness of aluminum with a bias applied.

On the other hand, the composition of the present invention containing tris (2,4,6-trimethoxyphenyl) phosphine of the formula (1) and an inorganic ion exchanger of the formula (2) Example) has a high glass transition temperature, has no decrease in Tg during moisture absorption, has excellent electrical properties, and has excellent corrosion resistance in a biased aluminum corrosion test. Was confirmed.

[0058]

As described above, the epoxy resin composition of the present invention is excellent in moisture resistance, heat resistance (high glass transition temperature), and high-temperature electrical characteristics by adopting the above-mentioned structure, and in particular, when a voltage is applied. It is excellent in moisture resistance in a state where it is made, and can be suitably used for sealing semiconductor devices.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication location H01L 23/31 (72) Inventor Shinichi Jingu 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture 10 Shinetsu Chemical Inside the Silicone Electronic Materials Research Laboratory, Industrial Co., Ltd. (72) Inventor Kenichi Totsuka 1-10, Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (56) References JP-A-3 JP-A-239718 (JP, A) JP-A-63-146917 (JP, A) JP-A-63-268727 (JP, A) JP-A-62-280215 (JP, A) JP-A-62-27723 (JP, A) )

Claims (3)

(57) [Claims] (1) an epoxy resin; (2) a phenolic curing agent; (3) a curing accelerator represented by the following formula (1): (4) silica powder, (5) the following general formula (2) A _x O _y (NO ₃ ) _z (OH) _w · h (H ₂ O) (2) (where A is Sb, Al and Represents one or more metals selected from Bi, x = 1 to 5, y = 1 to 7,
z = 0 to 3, w = 0.2 to 3, and h = 0 to 2. An epoxy resin composition comprising an inorganic ion exchanger having an average particle size of 5 μm or less and a maximum particle size of 30 μm or less as an essential component. Wherein the following formula alkenyl groups the alkenyl group-containing epoxy resin or alkenyl group-containing phenol resin ^{_{(3) H a R 1 b}} SiO 2- (a + b) / 2 ... (3) ( In the formula R ¹ represents a substituted or unsubstituted monovalent hydrocarbon group, and a and b are 0.001 ≦ a ≦ 1, 1 ≦ b ≦ 3,
It is a positive number satisfying 1 ≦ a + b <4. The number of silicon atoms in one molecule is an integer of 20 to 400, and the number of hydrogen atoms directly connected to the silicon atom in one molecule is an integer of 1 or more. The epoxy resin composition according to claim 1, further comprising a silicone-modified epoxy resin or a silicone-modified phenol resin, which is a polymer obtained by adding a SiH group of the organosilicon compound represented by the formula (1). 3. A semiconductor device sealed with a cured product of the epoxy resin composition according to claim 1.