JP2001226562A - Composition, liquid sealing material composition for flip- chip, and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition low in viscosity, excellent in flowability and giving a cured product excellent in heat adhesion resistance, humidity resistance and flexural modulus. SOLUTION: The composition comprises (A) an epoxy compound having a cyclic skeleton and liquid at 25 deg.C, (B) an acid anhydride liquid at 25 deg.C, (C) an acrylic thermoplastic polymer having a weight-average mol.wt. of not larger than 100,000, (D) a curing catalyst and (E) a spherical silica having an average particle size of 2-10 μm and a specific area of not larger than 2 m2/g and the amount of the component (E) is 40-85 mass%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a composition having a low viscosity and excellent fluidity. In particular, a cured product having excellent heat resistance, moisture resistance and flexural modulus can be obtained. It relates to useful compositions.

[0002]

2. Description of the Related Art Conventionally, a wire bonding mounting method has been often used for connection between a connection terminal of a semiconductor bare chip and a terminal electrode of a circuit pattern on a connection substrate. However, in recent years, the degree of integration of semiconductor devices has been greatly improved. In addition, the number of connection terminals per unit area is increasing. As a result, the distance between connection terminals tends to be narrower, and it is currently difficult to cope with the conventional mounting method.

In recent years, a so-called flip-chip mounting method, in which solder bumps and gold bumps are separated and mounted by a face-down bonding method, is used to connect the connection terminals of the semiconductor bare chip to the terminal electrodes on the connection substrate. Attempts to reduce the size of semiconductor packages have been actively studied.

In this flip-chip mounting method, a sealing material must be filled between the semiconductor bare chip and the connection substrate. However, since the gap is usually as small as 20 to 100 μm, the sealing material flows at room temperature. In this way, the gap was filled, and this was cured to form a sealing layer.

Examples of these room temperature liquid sealing materials include a room temperature liquid epoxy compound described in Japanese Patent Application Laid-Open No. 62-277421 and a filler having an average particle size of 5 to 30 μm. Examples of the sealant include a silicone-modified epoxy compound described in JP-A-4-351630 containing fused silica having an average particle size of 10 μm or less and a coarse particle content of 30 μm or more and 0.5% or less.

However, in such a conventional liquid sealing material, the amount of coarse particles contained in the filler is too large or too large, or the number of irregularly shaped particles is too large. When applied, when the sealing material is caused to flow between the chip and the connection substrate, the above-described coarse particles and irregularly shaped particles are aggregated between the connection bumps, resulting in uneven filler concentration in the sealing material. Or the flow speed tends to be extremely slow. For this reason, since regions having different linear expansion coefficients are non-uniformly present in the sealing material, peeling tends to occur in the solder reflow process.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to control the shape of a filler contained in a sealing material containing a liquid epoxy compound and a liquid acid anhydride and to mix a specific polymer compound, It is an object of the present invention to obtain a composition suitable for a flip chip mounting method, having a low viscosity and excellent fluidity, and having good heat resistance, moisture resistance and flexural modulus, and a semiconductor device using the same.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have used spherical silica particles as an inorganic filler and limited the specific surface area thereof to a specific range. As a result, it has been found that the viscosity of the obtained composition is low and the fluidity can be improved.

Further, by incorporating an acrylic thermoplastic polymer, the dispersion stability of the spherical silica is improved,
It is possible to form a sealing layer in which the filler is uniformly dispersed without separating the inorganic filler at the time of filling the sealing material,
It has been found that the heat resistance is also improved.

That is, the present invention relates to (A) an epoxy compound having a cyclic skeleton which is liquid at 25 ° C .;
Acid anhydride in liquid at 10 ° C, (C) weight average molecular weight 10
(D) a curing catalyst (E) a composition comprising spherical silica having an average particle diameter of 2 to 10 μm and a specific surface area of 2 m ² / g or less, wherein component (E) is 4
0 to 85% by mass, a composition useful as a liquid sealing material for flip chips, and a cured product of the composition at 25 ° C.
The liquid crystal sealing material composition for a flip chip having a flexural modulus of 0.1 to 20 GPa, and a semiconductor device sealed with a cured product of the composition.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The composition of the present invention comprises a liquid epoxy compound having a specific structure (A), a liquid acid anhydride (B), and an acrylic thermoplastic polymer (C) having a weight average molecular weight of 100,000 or less. And (D) a mixture of a curing catalyst and an inorganic filler (E) having a specific structure.

Hereinafter, each component will be described in detail.

In the present invention, “(meth) acrylic acid” means “acrylic acid or methacrylic acid”.

The component (A) of the present invention is a cyclic skeleton-containing epoxy compound which is liquid at 25 ° C., and is a basic component exhibiting heat resistance and adhesion as a main component of the sealing material.

Such an epoxy compound can improve heat resistance while maintaining adhesion. Among them, an epoxy compound having an alicyclic and / or aromatic ring skeleton in the molecule is preferable, and a compound having two or more epoxy groups is particularly preferable.

Specific examples of the epoxy compound (A) of the present invention include, for example, a bisphenol A type epoxy compound (trade name: Epikote 828, manufactured by Yuka Shell Epoxy) and a bisphenol F type epoxy compound (trade name: Epicoat 806) , Yuka Shell Epoxy Co., Ltd.), hydrogenated bisphenol A diglycidyl ether (trade name: Rica Resin HBE-100, manufactured by Shin Nippon Rika Co., Ltd.), 1,4-cyclohexanedimethanol diglycidyl ether (trade name:
Rica Resin DME-100, manufactured by Nippon Rika Co., Ltd., 3, 4
-Epoxycyclohexylmethyl (3,4-epoxy)
Cyclohexanecarboxylate (trade name: ERL42)
21, Union Carbide), bis (3,4-epoxycyclohexyl) adipate (trade name: ERL42)
99, manufactured by Union Carbide Co., Ltd.), diglycidylaniline (trade name: GAN, manufactured by Nippon Kayaku Co., Ltd.), hexahydrophthalic acid epichlorohydrin diglycidyl ester (trade name: AK-601, manufactured by Nippon Kayaku Co., Ltd.), bisphenol A
Diglycidyl ether of 2 mol adduct of propylene oxide (trade name: Epolite 3002, manufactured by Kyoeisha Chemical Co., Ltd.), resorcin diglycidyl ether (trade name: Denacol EX201, manufactured by Nagase Kasei Kogyo Co., Ltd.) Triglycidyl tris (2-hydroxyethyl) isocyanate Nurate (trade name: Denacol EX301, manufactured by Nagase Kasei Kogyo Co., Ltd.) and the like.

These can be used alone or in combination of two or more.

In order to exhibit excellent heat resistance and flexural modulus, among these, bisphenol A type epoxy compound, bisphenol F type epoxy compound, 1,4-cyclohexanedimethanol diglycidyl ether,
4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate and the like are preferred.

The composition of the present invention contains an epoxy compound other than the component (A) as long as it does not affect the performance.
That is, one or more epoxy compounds having no cyclic skeleton may be used in combination.

Specific examples of such an epoxy compound include, for example, those further used as the epoxy compound (A) include, for example, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, and polyethylene glycol diglycidyl ether. Propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, 2 , 2-dibromoneopentyl glycol diglycidyl ether, sorbitol polyglycidyl ether, sorbitanpo Glycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol triglycidyl ether, pentaerythritol Li Toots tiger glycidyl ether, polytetramethylene glycol diglycidyl ether, and the like.

Further, when the viscosity of the composition at 25 ° C. is 1
Within a range not exceeding 00 Pa · s, for example, solid bisphenol A type epoxy compound, halogenated bisphenol A
Epoxy compound, bisphenol S epoxy compound, diphenyl ether epoxy compound, hydroquinone epoxy compound, phenol novolak epoxy compound, biphenyl novolak epoxy compound, cresol novolak epoxy compound, naphthalene epoxy compound, biphenyl epoxy compound, dicyclo An epoxy compound such as a pentadiene phenol epoxy compound may be dissolved and used.

The component (B) of the present invention acts as a curing agent for the component (A), and together with the component (A), exerts heat resistance, adhesiveness, and other properties particularly required for a sealing material. It is a component of.

In order to enhance the effect of lowering the viscosity of the composition, the viscosity of the component (B) at 25 ° C.
It is preferable to set the range to mPa · s or less.

Specific examples of the component (B) include, for example, trialkyltetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, dodecenylphthalic anhydride and the like. However, these may be used alone or in combination of two or more.

In the present invention, the mixing ratio of component (A) to component (B) is such that the epoxy equivalent of component (A) is a
And the acid anhydride equivalent of the component (B) is b, a: b
= 1: 2 to 2: 1, preferably a: b = 0.8: 1 to 1: 0.8.

In the present invention, the total use ratio of the components (A) and (B) is 6 in the total amount of the components (A) to (D).
The range of 0 to 99.99% by mass, particularly the range of 79 to 96.9% by mass is preferred.

The component (C) of the present invention has a weight average molecular weight of 1
It is an acrylic thermoplastic polymer of 00000 or less, and is a component for improving the dispersion stability of the inorganic filler.

When the sealing material composition containing the component (C) is injected into a narrow gap between the semiconductor bare chip and the connection substrate, the sealing layer in which the inorganic filler is uniformly dispersed without separation is obtained. It can be formed.

Specific examples of component (C) include, for example, (meth) acrylic acid, methyl (meth) acrylate, (meth)
Ethyl acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic acid 2-ethylhexyl, lauryl (meth) acrylate, stearyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) 4-hydroxybutyl acrylate, glycidyl (meth) acrylate, dimethyl (meth) acrylate, aminomethyl,
Diethylaminomethyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, allyl (meth) acrylate, (meth) acrylic 2-ethoxyethyl acid, (meth)
Homopolymers or copolymers of one or more of (meth) acrylic monomers such as isobornyl acrylate and phenyl (meth) acrylate are exemplified.

The weight average molecular weight of the acrylic thermoplastic polymer (C) is 100,000 or less, preferably in the range of 5,000 to 100,000, more preferably 10 to 100,000.
000 to 70,000.

The component (C) has a weight average molecular weight of 10,000.
If it exceeds 0, the viscosity of the obtained encapsulant composition will increase extremely, and the workability of injecting into the narrow gap between the semiconductor bare chip and the connection substrate tends to be poor.

The proportion of the component (C) is not particularly limited, but is preferably in the range of 1 to 30% by mass, more preferably 3 to 20% by mass, based on the total amount of the components (A) to (D).
If the amount of the component (C) is less than 1% by mass, the dispersibility of the spherical silica (E) tends to be inferior. If the amount exceeds 30% by mass, the heat resistance and flexural modulus of the cured product of the obtained composition are reduced. It tends to decrease.

The composition of the present invention uses a curing catalyst (D).

Specific examples of the component (D) include, for example,
N, N'-dimethylpiperazine, pyridine, picoline,
Benzyldimethylamine, 2 (dimethylaminomethyl)
Phenol, 2,4,6-tris (dimethylaminomethyl) phenol, 1,8-diazabiscyclo (5,4
0) Tertiary amines such as undecene-1; 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2
-Ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1
-Benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-
Undimilimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4
-Methylimidazolium trimellitate, 1-cyanoethyl-2-undecylimidazolium trimellitate,
1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,
4-diamino-6- [2'-ethyl-4-methylimidazolyl (1 ')]-ethyl-s-triazine, 2,4-
Diamino-6- [2'-undecylimidazolyl] -ethyl-s-triazine, 2,4-diamino-6- [2 '
-Methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-
Dihydroxymethylimidazole, 2-phenyl-4-
Imidazole compounds such as methyl-5-di (2-cyanoethoxy) methylimidazole and 1-cyanoethyl-2-phenyl-4,5-di (2-cyanoethoxy) methylimidazole; 1,3-bis (hydrazinocarboethyl ) -5-isopropylhydantoin, 7,11-octadecadien-1,18-dicarbohydrazide, eicosane diacid dihydrazide, adipic acid dihydrazide compound, dicyandiamide and the like.

The proportion of the component (D) is not particularly limited, but is preferably 0.01 to 1 in the total amount of the components (A) to (D).
A range of 0% by weight, particularly a range of 0.1 to 1% by weight is particularly preferred. If the amount of the component (D) is less than 0.01% by mass, the curability tends not to be sufficiently exerted.
If the amount exceeds 0% by mass, the viscosity of the obtained sealing material composition tends to increase and the moisture resistance tends to decrease.

The composition of the present invention contains an inorganic filler as an essential component for lowering the linear expansion coefficient of the obtained encapsulant and approaching the linear expansion coefficient of the semiconductor bare chip.

The component (E) of the present invention has an average particle diameter of 2 to 10.
It is a spherical silica (E) having a diameter of ² μm and a specific surface area of 2 m ² / g or less.

When crushed silica or fused silica obtained by melting crushed silica is used as the inorganic filler component of the composition used in the flip chip mounting method, the viscosity of the obtained sealing material composition increases and the fluidity becomes poor. And the filling property tends to decrease.

Further, in order to fill the narrow gap of 20 to 100 μm in which a large number of connection bumps between the semiconductor bare chip and the connection substrate are arranged with the composition by utilizing the capillary phenomenon,
It is necessary that the average particle size of the component (E) be within the range of 2 to 10 μm.

When the average particle size is smaller than 2 μm, the viscosity of the resulting composition tends to increase and the fluidity tends to decrease because the specific surface area of silica is too large. In the method, while the obtained composition is injected between the semiconductor bare chip and the connection substrate, silica tends to aggregate around the connection bumps and the flow tends to stop halfway.

The specific surface area of the component (E) must be within a range of 2 m ² / g or less in order to suppress an increase in the viscosity of the composition. In a composition in which spherical silica having a specific surface area of more than 2 m ² / g is dispersed, the viscosity is excessively increased, the fluidity is reduced, and the filling between the semiconductor bare chip and the connection substrate tends to be poor.

In order to improve the filling rate of the inorganic filler, the component (E) is adjusted so that the average particle size of the component (E) is in the range of 2 to 10 μm and the specific surface area is in the range of 2 m ² / g or less.
In the range of 30% by mass or less in the components, the particle size is 0.1 to 1 μm.
Spherical silica as small as may be used in combination.

The proportion of the component (E) used is (A) to (E)
In the components, it is in the range of 40 to 85% by mass, preferably 50 to 8%.
The range is 0% by mass.

When the use amount of the component (E) is less than 40% by mass, the obtained sealing material composition tends to have a large shrinkage stress upon curing, and the semiconductor bare chip may be destroyed. If it exceeds 85% by mass, the viscosity of the sealing material composition tends to be too high, and the fluidity as a sealing material composition for flip chips tends to be insufficient.

The composition of the present invention may further comprise, if necessary,
Various additives can be blended.

For example, pigments such as carbon black, dyes, antioxidants, leveling agents, dispersants, flame retardants, flame retardant auxiliaries, coupling agents and the like can be used.

The composition of the present invention can be obtained by blending the above-mentioned various components and mixing them uniformly. The viscosity of the composition is not particularly limited.
The viscosity at 5 ° C. is preferably in the range of 1 to 100 Pa · s. If the viscosity is lower than 1 Pa · s, the inorganic filler tends to agglomerate during filling.
If the value exceeds a · s, there is a tendency that a sufficient filling property cannot be obtained as a composition for a flip chip.

In the composition of the present invention, the cured product has a flexural modulus in the range of 0.1 to 20 GPa, more preferably 1 to 20 GPa.
It is preferably in the range of 15 GPa to 15 GPa.

When the flexural modulus is less than 0.1 GPa, sufficient heat-resistant adhesiveness tends not to be obtained.
Exceeding a, if the substrate connecting the semiconductor bare chip to the flip chip is an organic substrate, stress distortion in the solder reflow process due to the difference in the coefficient of linear expansion between the two cannot be relaxed, and peeling may occur. Tend to be higher.

In the semiconductor device of the present invention, after the semiconductor bare chip is mounted on the connection substrate with the connection bump, the sealing material composition is filled between the semiconductor bare chip and the connection substrate and cured. This filling method is not particularly limited, for example, by a conventionally known solder reflow method,
A method of mounting a semiconductor bare chip on a connection board with connection bumps such as solder bumps, then dropping an appropriate amount of the semiconductor bare chip on one side of the semiconductor bare chip in an atmosphere of 50 to 80 ° C., and filling it by utilizing a capillary phenomenon.

The method of curing the filled composition is not particularly limited. For example, the curing temperature in a hot-air oven or the like is in the range of 100 to 220 ° C. for 15 minutes to 4 hours. A method of thermally curing is used. Further, the heating method may be implemented by dividing the temperature range into several steps.

If the curing temperature is lower than 100 ° C., the encapsulant composition of the present invention tends to be insufficiently cured,
When the temperature exceeds 20 ° C., when the connection substrate used for the flip chip is an organic substrate, it tends to be thermally decomposed.

If the curing time is less than 15 minutes, the curing tends to not proceed sufficiently, and if it exceeds 4 hours, the productivity tends to be poor.

[0054]

The present invention will be specifically described below with reference to examples and comparative examples.

Example 1 An epoxy compound, a liquid acid anhydride, an acrylic thermoplastic polymer, and an inorganic filler were uniformly mixed at the compounding amounts shown in Table 1, and dispersed with a three-roll mill to obtain eight kinds of materials. A composition was obtained. After defoaming the obtained composition under vacuum,
The viscosity at 25 ° C. was measured using a mold viscometer. The results are shown in Table 1.

For each of the eight compositions thus obtained, a semiconductor bare chip of 10 × 10 × 0.4 mm was bonded on a glass substrate via a solder bump (the distance between the semiconductor bare chip and the glass substrate was 80 μm). Injection was performed from one side of the semiconductor bare chip on a hot plate at ° C., and the time when the composition finished flowing to one side on the opposite side of the injection was measured as the filling time.

This filled material is heated at 150 ° C. in air.
Curing was performed for one hour, and the filling state of the composition was observed from the glass substrate side using an optical microscope. The results are shown in Table 1.

Next, the above eight compositions were injected and sealed in a flip chip in which a semiconductor bare chip was connected via a solder bump on a glass epoxy substrate in the same manner as described above, and the mixture was then heated at 30 ° C. and 70% PH. After leaving for 192 hours, it was put into an N ₂ reflow bath at a peak temperature of 230 ° C. for 90 seconds, taken out, observed with an ultrasonic probe, and the presence or absence of peeling of the cured composition was evaluated as heat resistance and humidity resistance. The results are shown in Table 1.

The modulus of elasticity of the cured composition is determined according to JIS.
-Standard size of test piece described in K7171 (80 mm x 10 m
m × 4 mm) were filled with the above eight compositions,
JIS-K using a sample obtained by curing at ℃ for 1 hour.
Table 1 shows the results measured by a method based on 7171.

[0060]

[Table 1] The units of the components (A) to (E) in the table are parts by mass.

* 1) Numerical values in parentheses indicate epoxy equivalents.

* 2) Numerical values in parentheses indicate acid anhydride equivalents.

* 3) Measurement was not possible because the flow stopped during filling.

YL983: Bisphenol F type epoxy compound manufactured by Yuka Shell Epoxy (epoxy equivalent: 169,
ERL4221: alicyclic epoxy compound manufactured by Union Carbide (epoxy equivalent 134, viscosity 4 at 25 ° C.)
DME100: an alicyclic epoxy compound manufactured by Shin-Nippon Rika Co., Ltd. (epoxy equivalent: 157, viscosity at 25 ° C .: 60 mPa · s)
s) W100: Fatty epoxy compound manufactured by Shin-Nippon Rika Co., Ltd. (epoxy equivalent: 152, viscosity at 25 ° C .: 21 mPa · s) MT500: Methyltetrahydrophthalic anhydride manufactured by Shin-Nippon Rika Co., Ltd. (acid anhydride equivalent: 170, viscosity at 25 ° C .: 47)
MH700: Methyl hexahydrophthalic anhydride manufactured by Shin Nippon Rika Co., Ltd. (acid anhydride equivalent 162, viscosity at 25 ° C. 65)
m1: Pas) P1: Methyl methacrylate (37% by mass) / n-butyl methacrylate (62% by mass) / methacrylic acid (1% by mass) copolymer (weight average molecular weight: 45,000) P2: Methyl methacrylate (94% by mass) %) / Methyl acrylate (6% by mass) copolymer (weight average molecular weight 1500)
00) 2E4MZCN: 1-cyanoethyl-2-ethyl-4-
Methylimidazole SSB515: Spherical silica manufactured by Izumi Tech (average particle size: 6 μm, maximum particle size: 15 μm, specific surface area: 1.1 m ² / g) QS4: Spherical silica manufactured by Mitsubishi Rayon (average particle size: 4 μm)
m, maximum particle diameter 12 μm, specific surface area 0.7 m ² / g) SOE2: spherical silica manufactured by Tatsumori (average particle diameter 0.5 μm,
Maximum particle size 2 μm, specific surface area 8 m ² / g) SSPF1: fused silica manufactured by Izumi Tech Co. (average particle size 1
4 μm, maximum particle size 40 μm, specific surface area 5 m ² / g)

[0065]

As described above, according to the present invention, the filler contained in the encapsulant containing the liquid epoxy compound and the liquid acid anhydride is spherical and the specific surface area is limited to a specific range. By using a high molecular compound, it is possible to obtain a composition having a low viscosity and excellent fluidity, and a cured product obtained by using the composition as a sealing material for a flip chip has high heat resistance and moisture resistance. It has good properties and flexural modulus and is very useful industrially.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) H01L 23/31 F-term (Reference) 4J002 BG01X BG04X BG05X BG06X BG07X CD01W CD02W CD03W CD05W CD08W CD13W CD14W DJ016 EF127 EN068 EN108 ER008 048008 EU0 EU118 EU138 EU178 EU188 FA086 FD016 FD147 FD158 GQ05 HA02 4J036 AA01 AD01 DA01 DB05 DB15 DB21 DC05 DC06 DC31 DC35 DC39 DC40 DC45 FA05 FB03 JA07 4M109 AA01 BA04 CA04 EA03 EA12 EC05 EC09 EC20

Claims (4)

[Claims] 1. An epoxy compound having a cyclic skeleton which is liquid at 25 ° C., an acid anhydride which is liquid at 25 ° C., an acrylic thermoplastic polymer having a weight average molecular weight of 100,000 or less, ) Curing catalyst (E) A composition comprising spherical silica having an average particle size of 2 to 10 μm and a specific surface area of 2 m ² / g or less, wherein component (E) is 4
A composition comprising 0 to 85% by mass. 2. The composition according to claim 1, which is used as a liquid sealing material for flip chips. 3. The cured product has a flexural modulus at 25.degree.
2. The composition according to claim 1, wherein the composition is 1 to 20 GPa. 4. A semiconductor device encapsulated with a cured product of the composition according to claim 1.