JPH04224859A - Resin composition - Google Patents

Abstract

PURPOSE:To prepare a resin compsn. excellent in the resistance to heat and crack by compounding an org. component contg. a specific polymaleimide compd. a dicyclopentadiene-phenol resin, and optionally an epoxy resin with an inog. filler. CONSTITUTION:A resin compsn. which is prepd. by compounding an org. component contg. a polymaleimide compd. of formula 1 (wherein R1 is an m-valent org. group having at least two carbon atoms; and m is an integer of 2 or higher), a dicyclopentadiene-phenol resin of formula II (wherein R2 is H or a 4C or lower alkyl group; and n is an integer of 0-5), and optionally an epoxy resin with an inorg. filler.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent heat resistance and crack resistance. In other words, it is related to resin compositions that aim to improve heat resistance and crack resistance as insulating materials, laminate materials, and resin sealing materials for electronic/electrical parts, semiconductor fields, etc., and particularly requires solder crack resistance. The present invention relates to a resin composition suitable for encapsulating semiconductor devices.

0002

BACKGROUND OF THE INVENTION In recent years, there has been a demand for resin compositions with excellent heat resistance and crack resistance in the fields of electronic/electrical parts, semiconductors, etc. For example, in the field of electrical and electronic components, especially semiconductors, as equipment and equipment that use these components become smaller and thinner, there is a tendency for the density of mounting on wiring boards to be increased, and the components themselves are becoming smaller and thinner. There is a trend toward multifunctionality. As a material for sealing this, there is a strong desire to develop a resin composition that has excellent heat resistance against high-temperature soldering in the soldering process to wiring boards. Conventionally, resin compositions for such uses, so-called semiconductor encapsulation resin compositions, have been mainly composed of epoxy resins such as O-cresol novolac type epoxy resins, phenol novolac resins as curing agents, and silica. Resin compositions have excellent moldability and reliability and are the mainstream in this field.

0003

However, resin-sealed semiconductor devices are being replaced by surface-mounted semiconductor devices due to the above-mentioned trend toward high-density packaging. In such a surface mount type semiconductor device, unlike a conventional insertion type semiconductor device, the entire semiconductor device is exposed to a soldering temperature of 200° C. or higher during the soldering process to a substrate. At this time, a problem has arisen in that cracks occur in the sealing resin, significantly reducing the reliability of the semiconductor device. Cracks occur during soldering when moisture absorbed during storage of the semiconductor device expands explosively at temperatures of 200° C. or higher, generating stress, and when this stress exceeds the strength of the sealing resin, cracks occur. At this time, the stress applied to the resin is approximately expressed by the following equation. σ=k・p・a2/t2 However, σ: Stress applied to the resin k: Constant p: Water vapor pressure a: Length of the short side of the die pad t: Thickness of the resin at the bottom of the die pad Therefore, the glass transition temperature of the sealing resin Imide-based resins have been studied in order to increase the resin strength and provide sufficient resin strength to overcome the stress caused by expansion of water. However, the cured product of imide resin tends to have an increased water absorption rate, which, considering the above equation, increases the stress applied to the resin and makes it impossible to take advantage of the high strength characteristic of imide resin. Therefore, lowering the water vapor pressure during soldering by reducing the water absorption rate is an effective means for suppressing the occurrence of cracks.

An object of the present invention is to provide a resin composition with excellent heat resistance and crack resistance, which can be applied to resin-encapsulated semiconductor devices that require solder crack resistance during mounting. Furthermore, it is an object of the present invention to provide a resin composition that can be widely applied to electronic and electrical parts for improving the heat resistance and crack resistance of insulating materials, laminates, and the like.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the present inventors, as a result of intensive research, have used polymerimide, which can be cured at a relatively low temperature as an imide resin, and have further improved the water absorption. By using dicyclopentadiene phenol resin, which has a low water absorption rate, in combination, we succeeded in significantly improving the strength of the sealing resin without increasing its water absorption rate, and completed the present invention.

That is, the present invention provides an organic component containing a polymaleimide represented by the general formula (1) and a dicyclopentadiene phenol resin represented by the general formula (2), or an organic component containing an epoxy resin in addition to these. This is a resin composition containing a component and an inorganic filler. More specifically, as component (A), (a) general formula (1);

A polymaleimide compound represented by the following formula (wherein R1 represents an m-valent organic group having at least 2 carbon atoms, and m represents a positive integer of 2 or more) and (b) the general formula (2);

[Formula 8] (wherein, R2 represents a hydrogen atom or an alkyl group having 4 or less carbon atoms, and n represents an integer of 0 to 5) or a combination of the resin and phenols. and an inorganic filler as the (B) component, and the above-mentioned (a) polymaleimide compound and (b) dicyclopentadiene as the (A) component. A resin composition comprising a phenol resin or a mixture of the resin and phenols, and further contains (c) an organic component including an epoxy resin and an inorganic filler as a component (B), and is particularly resistant to solder cracks. This is a resin composition for semiconductor encapsulation that is suitable for semiconductor encapsulation with excellent properties.

[0007] In the composition of the present invention, the organic component (A)
The component (a) used as is a polymaleimide compound represented by general formula (1). The polymaleimide compound represented by the general formula (1) is a compound having two or more maleimide groups in one molecule. Examples of such polymaleimide compounds include N,N'-ethylene bismaleimide, N,N'-hexamethylene bismaleimide, N,N'-(1,3-phenylene) bismaleimide, and N,N'- (1,4-phenylene) bismaleimide, bis(4-maleimidophenyl) methane, bis(4-maleimidophenyl) ether, bis(3-
chloro-4-maleimidophenyl) methane, bis(4-maleimidophenyl) sulfone, bis(4-maleimidophenyl)
maleimidocyclohexyl) methane, 1,4-bis(4-maleimidophenyl) cyclohexane, 1,
4-bis(maleimidomethyl)cyclohexane, 1
,4-bis(maleimidomethyl)benzene, 1,3
-bis(4-maleimidophenoxy)benzene, 1
, 3-bis(3-maleimidophenoxy) benzene, bis[4-(3-maleimidophenoxy) phenyl]methane, bis[4-(4-maleimidophenoxy) phenyl]methane, 1,1-bis[4-(3 - maleimidophenoxy) phenyl]ethane, 1,1-bis[4-(4-maleimidophenoxy) phenyl]
Ethane, 1,2-bis[4-(3-maleimidophenoxy) phenyl]ethane, 1,2-bis[4-(4-
maleimidophenoxy) phenyl]ethane, 2,2
-bis[4-(3-maleimidophenoxy) phenyl]propane, 2,2-bis[4-(4-maleimidophenoxy) phenyl]propane, 2,2-bis[4
-(3-maleimidophenoxy) phenyl]butane, 2,2-bis[4-(4-maleimidophenoxy)
Phenyl]butane, 2,2-bis[4-(3-maleimidophenoxy)phenyl]-1,1,1,3,3
, 3-hexafluoropropane, 2,2-bis[4-(
4-maleimidophenoxy) phenyl]-1,1,
1,3,3,3-hexafluoropropane, 4,4'-
bis(3-maleimidophenoxy) biphenyl,
4,4'-Bis(4-maleimidophenoxy) biphenyl, bis[4-(3-maleimidophenoxy)
phenyl]ketone, bis[4-(4-maleimidophenoxy) phenyl]ketone, bis[4-(3-maleimidophenoxy) phenyl]sulfide, bis[4
-(4- Maleimidophenoxy) Phenyl] sulfide, Bis[4-(3- Maleimidophenoxy) Phenyl] sulfoxide, Bis[4-(4- Maleimidophenoxy) Phenyl] sulfoxide, Bis[4-(
3-maleimidophenoxy) phenyl]sulfone,
Bis[4-(4-maleimidophenoxy) phenyl]sulfone, bis[4-(3-maleimidophenoxy) phenyl]ether, bis[4-(4-maleimidophenoxy) phenyl]ether, polymaleimidophenylmethylene, and general formula (5):

Examples include polymaleimide compounds represented by the following formula (wherein l is 0 to 10 on average). Further, these polymaleimide compounds may be used alone or in combination of two or more types.

[0008] Furthermore, in the composition of the present invention, an organic component (
Component (b) used as A) is a dicyclopentadiene phenol resin represented by the general formula (2) or a mixture of the resin and phenols, and the dicyclopentadiene phenol resin represented by the general formula (2) The phenol resin may be used alone or in combination with a compound having two or more phenolic hydroxyl groups in one molecule. The dicyclopentadiene phenol resin represented by general formula (2) can be obtained by reacting phenol or alkyl-substituted phenol with dicyclopentadiene. In order to obtain the effects of the present invention, a dicyclopentadiene phenol resin represented by general formula (2) with a repeating number n of 5 or less is preferably used, and when n exceeds 5, the viscosity of the resin composition decreases. This makes melt kneading and transfer molding difficult.

In the composition of the present invention, phenol compounds having two or more phenolic hydroxyl groups in one molecule that can be used in combination with the dicyclopentadiene phenol resin represented by general formula (2) include phenol and substituted phenol. The general formula (3
)

[Formula 10] (wherein, R3 is a hydrogen atom, a hydroxyl group, or a carbon number of 1 to 9
is an alkyl group, and r is an integer of 1 or more. 8) and (9);

[Chemical formula 11]

[Chemical formula 12]

[Chemical formula 13]

An aralkyl resin represented by the formula (wherein q is an integer of 0 to 5), and trihydroxyphenylmethane,
Examples include polyhydric phenols such as tetrahydroxyphenylethane and alkanetetrakisphenol. When the phenol compound is used in combination with the dicyclopentadiene phenol resin represented by the general formula (2), it is preferable that the ratio of both is in the range of 0 to 100 parts by weight per 100 parts by weight of the former. .

Furthermore, when component (c) is included as the organic component (A), the epoxy resin used as component (c) is not suitable for reactions between phenol, substituted phenols, and aldehydes in terms of heat resistance and electrical properties. General formula (4) derived from the product novolac type phenolic resin;

[Chemical 1
5] (wherein R4 represents a hydrogen atom or an alkyl group having 1 to 9 carbon atoms, and p represents an integer of 1 or more) is most preferably used, but at least 2 Any epoxy group having 2 epoxy groups can be used. Specifically, epoxy resins derived from compounds having two or more active hydrogens in one molecule, for example,
Bisphenol A, bisphenol F, resorcinol, bishydroxydiphenyl ether, bishydroxybiphenyl, tetrabromobisphenol A, trihydroxyphenylmethane, tetrahydroxyphenylethane,
Polyhydric phenols such as alkanetetrakisphenol;
Polyhydric alcohols such as ethylene glycol, neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol, diethylene glycol, polypropylene glycol; Amines such as ethylenediamine, aniline, bis(4-aminophenyl)methane; adipic acid, phthalic acid, Epoxy resin obtained by reacting polycarboxylic acids such as isophthalic acid with epichlorohydrin or 2-methylepichlorohydrin, and general formula (1
0), (11);

[Chemical formula 16]

embedded image (In each formula, X represents an integer of 0 to 5), and one or more of these epoxy resins are used.

[0011] The above epoxy resin may also be in the form of an oil,
It can also be used after being modified with a rubber-like silicone compound. For example, as disclosed in JP-A-62-270617 and JP-A-62-273222, silicone-modified epoxy resins are produced by dispersing fine particles of silicone polymer in a reaction product of epoxy resin and vinyl polymer. It is. In the composition of the present invention, the component (A) is a polymaleimide compound represented by the general formula (1) of the component (a) and the general formula (
The amount of the dicyclopentadiene phenol resin represented by 2) or the mixture of this resin and phenol is usually 100 parts by weight of component (a) and 1 part by weight of component (b).
It ranges from 0 to 500 parts by weight, preferably from 25 to 300 parts by weight.

In addition, in the composition of the present invention, when component (A) contains component (c), the general formula of component (a) (
A polymaleimide compound represented by 1), a dicyclopentadiene phenol resin represented by general formula (2) as component (b) or a mixture of this resin and phenols, and (c
The blending amount of the epoxy resin of the component (a) is 100% of the component (a).
The total amount of component (b) and component (c) is 1 part by weight.
0 to 500 parts by weight, preferably 25 to 300 parts by weight, based on the dicyclopentadiene phenol resin represented by the general formula (2) of component (b) or the mixture of this resin and phenols (c) The equivalent ratio of the component epoxy resin is in the range of 0.1 to 10, preferably 0.5 to 2.0.
is within the range of In the present invention, the resin composition may be blended and kneaded in a conventional manner, or the polymaleimide compound may be added to part or all of the above component (b) or a mixture of components (b) and (c) in advance. You can also leave it dissolved,
Alternatively, these may be used as a reacted prepolymer.

The inorganic filler used as component (B) in the composition of the present invention can be an inorganic powder or fibrous material, such as crystalline silica, fused silica, alumina, silicon nitride. , silicon carbide, talc, calcium silicate, calcium carbonate, mica, clay, titanium white, etc.; fibrous materials such as glass fiber, garbon fiber, etc., but from the viewpoint of thermal expansion coefficient and thermal conductivity, crystalline , fusible silica powder is preferred. Furthermore, from the viewpoint of fluidity during molding, spherical silica powder or a mixture of spherical and irregularly shaped silica powders are preferred. The amount of inorganic filler (B) component is (
The total amount of the polymaleimide compound represented by the general formula (1) as the component (a) and the dicyclopentadiene phenol resin represented by the general formula (2) as the component (b) or a mixture of the resin and phenols, or 100 parts by weight of the total amount of the epoxy resin (c) added to this
~900 parts by weight, preferably 2
00 to 600 parts by weight.

[0014] Furthermore, from the viewpoint of mechanical strength and heat resistance, it is preferable to use a coupling agent in combination with the above-mentioned inorganic filler for the purpose of improving adhesiveness with the resin. Coupling agents such as titanate, aluminate and zircoaluminate can be used. Among them, silane coupling agents are preferred;
In particular, a silane coupling agent having a reactive functional group is most preferred. Examples of such silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, N-(2-aminoethyl)3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)
3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-anilinopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3, Examples include 4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane, and one or more of these may be used. These silane coupling agents are preferably fixed in advance on the surface of the inorganic filler by adsorption or reaction.

In the present invention, when curing the resin composition, it is desirable to contain a curing accelerator.
Such curing accelerators include 2-methylimidazole,
Imidazoles such as 2-methyl-4-ethylimidazole and 2-heptadecylimidazole; Amines such as triethanolamine, triethylenediamine, and N-methylmorpholine; Organic phosphines such as tributylphosphine, triphenylphosphine, and tritolylphosphine. ;
tetraphenylphosphonium tetraphenylborate,
Tetraphenylboron salts such as triethylammonium tetraphenylborate; 1,8-diaza-bicyclo(
5,4,0) undecene-7 and its derivatives. These curing accelerators may be used alone or in combination of two or more types, and if necessary, an organic peroxide or an azo compound can also be used in combination. The content of these curing accelerators is determined between the (a) component, the polymaleimide compound represented by the general formula (1), and the (b) component, the dicyclopentadiene phenol resin represented by the general formula (2), or the resin. 0 for the total amount of the mixture with phenols or the total amount of the epoxy resin as component (c)
．． It ranges from 0.01 to 10% by weight.

[0016] In addition to various components, the resin composition of the present invention contains, if necessary, reactive compounds commonly used for imide resins such as diallyl phthalate, triallyl isocyanate, and o,o'-diallyl bisphenol A. Diluents; various silicone oils; mold release agents such as fatty acids, fatty acid salts, and wax; flame retardants such as bromine compounds, antimony, and phosphorus;
A coloring agent such as carbon black can be blended, mixed and kneaded to form a molding material.

[0017]

[Examples] The present invention will be specifically explained below using examples. The test method is as follows.・Glass transition temperature: TMA method ・Bending strength and flexural modulus: JIS K-6911
Water absorption Ralflow: Using a test piece for bending test, 65℃
, the weight increase was measured after being left in a constant temperature and humidity chamber at 95% for 168 hours.・V. P. S. Test: Semiconductor device for testing at 65°C.
After being left in a constant temperature and humidity chamber at 95% for 168 hours, the semiconductor devices were immediately placed in a molten solder bath at 260° C., and the number of semiconductor devices with cracks in the package resin was counted. The test value is expressed as a fraction, and the numerator is the number of cracked semiconductor devices,
The denominator is the total number of semiconductor devices tested.

Synthesis Example 1 (Dicyclopentadiene Phenol Resin-1) A glass reactor equipped with a thermometer and a stirring device was charged with 1645 g (17.5 mol) of phenol and 1 g of trifluoromethanesulfonic acid as a catalyst, and stirred. The temperature was raised and maintained at 120°C. Next, 463 g (3.5 mol) of dicyclopentadiene was added dropwise to this over 5 hours. After the dropwise addition, aging was performed at the same temperature for 5 hours to complete the reaction. Next, this viscous reaction solution was heated under vacuum to an internal temperature of 1.
After raising the temperature to 60°C and collecting unreacted phenol, etc., the reactor was immediately discharged and allowed to cool. In this way, 1003 g of dicyclopentadiene phenol resin-1, which is a dark red copolymer of phenol and dicyclopentadiene, was obtained. JIS-K-2 of this
The softening point measured by the ring and ball method according to No. 548 was 103° C., and the hydroxyl equivalent was 174.7 g/eq.

Synthesis Example 2 (Dicyclopentadiene phenol resin-2) 270 g (2.5 mol) of p-cresol and 0.5 g of pentafluoroethanesulfonic acid as a catalyst were placed in a glass reactor equipped with a thermometer and a stirring device. was charged, and the temperature was raised while stirring and maintained at 90°C. Next, 132.2 g (1 mol) of dicyclopentadiene was added dropwise to this over 4 hours. After the dropwise addition, aging was carried out at a temperature range of 90 to 100° C. for 5 hours to complete the reaction. Next, this viscous reaction solution was heated to an internal temperature of 160° C. under vacuum, and unreacted p-cresol and the like were recovered. Add 500 g of toluene to this distillation residue to make a homogeneous solution, and add water under stirring.
Added 500g. After maintaining the reflux state for 1 hour, the mixture was allowed to stand, and the mixture was separated into two layers. After removing the lower aqueous layer and distilling toluene from the upper toluene layer under vacuum, the mixture was immediately discharged and allowed to cool. In this way, 280 g of dicyclopentadiene phenol resin-2, which is a brownish-brown copolymer of p-cresol and dicyclopentadiene, was obtained. The softening point of this product measured by the ring and ball method according to JIS-K-2548 is 128 °C, and the hydroxyl equivalent is 188
．． It was 3g/eq.

Examples 1 to 8 and Comparative Examples 1 and 2 Blends having the compositions (parts by weight) shown in Table 1 were mixed in a Henschel mixer, and then melted and kneaded for 3 minutes with a heated roll at 100 to 130°C. . This mixture was cooled, pulverized, and tableted to obtain a molding resin composition.

[0021] Furthermore, with the raw materials used in Table 1, Synthesis Example 1,
The following materials were used except those according to No. 2.・Phenol compound; novolac type phenol resin (P
N-80, manufactured by Nippon Kayaku Co., Ltd.) ・Epoxy resin; o-cresol novolac type epoxy resin (ECON-1020, manufactured by Nippon Kayaku Co., Ltd.) ・Inorganic filler: Spherical fused silica (Harimic S-CO, A mixture of 50 parts by weight of amorphous fused silica (Fuse Rex RD-8, manufactured by Tatsumori Co., Ltd.) and 50 parts by weight of silane coupling agent (SZ-6083, manufactured by Dow Corning Toray Silicone Co., Ltd.) ) made)

Transfer molding (180° C., 30 kg/kg) using the molding resin composition obtained as above.
cm2 for 3 minutes) to form test pieces for measuring physical properties. In addition, a test element (10 mm x 10 mm
transfer molding (180 °C, 3
0 kg/cm2 for 3 minutes) to obtain a test semiconductor device. These test moldings were tested before each test.
Post-curing was carried out at 180° C. for 6 hours. Table 2 shows the test results.
Shown below.

[0023]

[Table 1]

[Table 2]

[0024]

[Effect of the invention] As explained in the examples and comparative examples,
The resin composition according to the present invention can efficiently impart the heat resistance of an imide resin without impairing water absorption. Therefore, when a surface-mounted semiconductor device to which reflow and flow soldering methods are applied is encapsulated with this resin composition, a resin-encapsulated semiconductor device exhibiting excellent solder crack resistance and high reliability can be obtained. This is an industrially useful invention.

Claims (6)

[Claims] Claim 1: As component (A), (a) general formula (1); and (b) general formula (2); A resin composition comprising an organic component containing a dicyclopentadiene phenol resin represented by (representing an integer from 0 to 5) or a mixture of the resin and phenols, and an inorganic filler as component (B). . [Claim 2] As component (A), (a) general formula (1); (indicating a positive integer of ) and (b) general formula (2); (representing an integer from 0 to 5) or a mixture with the resin; (c) an epoxy resin; and (B) an inorganic filler as the component. Resin composition. 3. A resin composition for semiconductor encapsulation consisting essentially of the resin composition according to claim 1. 4. A resin composition for semiconductor encapsulation consisting essentially of the resin composition according to claim 2. 5. In the component (b), the phenol forming the mixture with the dicyclopentadiene phenol resin is a reaction product of phenol and/or substituted phenol with an aldehyde according to the general formula (3) [Chemical formula 5] (in the formula , R3 represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 9 carbon atoms, and r represents an integer of 1 or more. Sealing resin composition. 6. The epoxy resin (c) has the general formula (4) derived from a novolac type phenolic resin which is a reaction product of phenol and/or substituted phenol and aldehydes; 5. The resin composition for semiconductor encapsulation according to claim 4, which is an epoxy resin represented by the following formula: represents a hydrogen atom or an alkyl group having 1 to 9 carbon atoms, and p represents an integer of 1 or more.