JPH09316300A - Resin composition for semiconductor sealing use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition excellent in soldering crack resistance and capable of reducing the amount of flame retardant to be incorporated in, by blending a resin prepared by reaction of a polycarbodiimide with compound(s) bearing both graft-reactive group and carboxylic anhydride group with an epoxy resin and filter. SOLUTION: This resin composition excellent in soldering crack resistance and flame retardancy is obtained by blending (A) a modified polycarbodiimide resin prepared by grafting at least one kind of compound bearing both graft- reactive group and carboxylic anhydride group (e.g. trimellitic anhydride) to a polycarbodiimide prepared by reaction between diphenylmethane-4,4'- diisocyanate and phenyl isocyanate in toluene in the presence of a carbodiimidating catalyst such as 3-methyl-1-phenyl-3-phospholene-1-oxide at 110 deg.C, with (B) an epoxy resin (e.g. biphenyl-type epoxy resin) and (C) 60-95wt.% of a filler (e.g. noncrystalline silica).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for semiconductor encapsulation, more specifically, a resin for semiconductor encapsulation which contains a specific modified polycarbodiimide and is excellent in solder crack resistance and flame retardancy. It relates to a composition.

[0002]

2. Description of the Related Art Conventionally, a semiconductor chip is sealed in order to protect it from changes in the external environment and mechanical shock, and also to maintain the electrical insulation of the chip from the outside to ensure the reliability of the element for a long period of time. Is being done. This encapsulation method includes an airtight encapsulation method using ceramics and the like, and a resin encapsulation method, but the resin encapsulation method is widely adopted because it is suitable for mass production and has a low manufacturing cost. As a sealing resin, an epoxy resin is mainly used from the viewpoint of balance of physical properties, moldability, cost and the like. In recent years, the method of mounting components on a printed circuit board has shifted from the conventional pin insertion method of soldering each lead pin to a surface mounting method of exposing the entire package to high temperature for soldering. However, when soldering the package sealed with the conventional sealing resin by the surface mounting method, cracks occur in the resin part and reliability decreases, and there is a problem that it cannot be used as a product. Has become. for that reason,
Various improved methods have been investigated in order to prevent cracking during soldering. For example, a method using a resin composition containing a novolac type epoxy resin and a phenol aralkyl resin (Japanese Patent Laid-Open No. 59-67660), A method of using a biphenyl type epoxy resin as the epoxy resin (JP-A-1-108256), a method of using a mixture of tris (hydroxymethyl) methane and a phenol aralkyl resin as a curing agent (JP-A 1-292029),
A method using a mixture of a phenol aralkyl resin and a dicyclopentadiene-modified phenol resin as a curing agent (JP-A-4-35913), and a method using a resin composition containing a biphenyl type epoxy resin and an amino group-containing silane coupling agent ( JP-A-7-242799),
A method using a mixture of a polyglycidyl ether of a polyaddition product of a phenol and a polycyclic aliphatic hydrocarbon such as dicyclopentadiene and a biphenol type epoxy resin as an epoxy resin (JP-A-7-247409), bis ( 3,5-Dimethyl-4-hydroxyphenyl) -p-
A method of using a resin composition containing an epoxy resin containing xylylene diglycidyl ether as a main component and a curing agent containing a paraxylylene-modified phenol resin as a main component (JP-A-7-268070), bisphenol A, dicyclopentadiene and Method using resin composition containing copolycondensation type polyfunctional epoxy resin of 2,6-xylenol and dihydroxynaphthalene resin (JP-A-7-2782)
59), hydroxyphenylene bond to the curing agent, p
-A method using a compound having a xylylene bond and a phenylmethylene bond (JP-A-7-278272), and a method using a phenolic resin obtained by the reaction of a phenol compound and a metaxylylene compound as a curing agent (JP-A-7-309932). Gazette) is proposed. However, even if any of these methods is considerably improved in terms of the ability to prevent the occurrence of cracks, it cannot be said to be sufficient. On the other hand, the resin composition for semiconductor encapsulation is also required to have flame retardancy, and conventional epoxy resins have insufficient flame retardancy. Therefore, a flame retardant such as a halide or antimony trioxide or a flame retardant aid. Is compounded. However, in recent years, from the viewpoint of environmental protection and safety, it is strongly required to reduce the amount of these flame retardants / flame retardant aids to be used. The epoxy resin composition for semiconductor encapsulation having improved performance has not been improved at all. That is, the conventional epoxy resin composition for semiconductor encapsulation has improved solder crack resistance and flame retardant
It has not been possible to achieve a satisfactory level of reduction of the flame retardant auxiliary agent at the same time.

[0003]

An object of the present invention is to provide a resin composition for semiconductor encapsulation which is excellent in solder crack resistance and which can reduce the amount of flame retardant / flame retardant aid used. It is in.

[0004]

The present invention provides (A) polycarbodiimide with at least one compound having a graft reactive group and a carboxylic acid anhydride group (hereinafter referred to as "reactive compound"). A resin composition comprising a grafted resin (hereinafter referred to as "modified polycarbodiimide"), (B) epoxy resin and (C) filler, wherein the content of the filler is the total resin composition composition. 60 to 95
A gist of the present invention is a resin composition for semiconductor encapsulation, which is characterized in that the content is% by weight.

Hereinafter, the present invention will be described in detail. (A) Modified Polycarbodiimide The modified polycarbodiimide in the present invention comprises a resin obtained by grafting one or more reactive compounds onto polycarbodiimide. Polycarbodiimide, which is a raw material for the modified polycarbodiimide, is a thermosetting resin in itself, and is well known to give a cured product having high heat resistance and flame retardancy. Has no action to initiate the curing reaction of the epoxy resin. However, the modified polycarbodiimide has a structure in which a reactive compound residue having an acid anhydride group derived from a reactive compound is grafted onto the polymer chain of the polycarbodiimide, and the acid anhydride group is a curing reaction of the epoxy resin. Has the action of starting. Therefore, the modified polycarbodiimide functions as an initiator of the curing reaction of the epoxy resin by the action of the acid anhydride group. Although polycarbodiimide does not act to start the curing reaction of the epoxy resin, when the curing reaction of the acid anhydride group and the epoxy resin proceeds, the intermediate of the curing reaction becomes reactive with the carbodiimide group. Therefore, it is presumed that, as a result, the reaction between the epoxy resin and the modified polycarbodiimide occurs. As a result, the resin composition containing the modified polycarbodiimide of the present invention and the epoxy resin is heated and cured, and the two resin components react with each other to be compatibilized with each other, resulting in a homogeneous cured product. It has been found that it has extremely high heat resistance and also has excellent physical properties such as electrical characteristics, moisture resistance, and flame retardancy. further,
It has been found that, by adding a filler to such a modified polycarbodiimide and an epoxy resin, the problems in the prior art can be solved and an excellent resin composition for semiconductor encapsulation can be obtained, and the present invention has been completed. It has come to do.

<Polycarbodiimide> Polycarbodiimide is a resin obtained by decarboxylation condensation of a polyisocyanate compound, and specifically, is represented by the general formula (1) -N = C = NR ¹ -... (1) (however, , R ¹ represents a divalent organic group derived from a polyisocyanate compound). Polycarbodiimides and methods for their preparation are described, for example, by DJ Lyman et al. In Die Makromol. Chem., 67, 1 (19).
63), J. Am. Chem. Soc., 80, 5495 (195) by E. Deyer et al.
8), J. Appl. Polym. Sci., 21,1 by LM Alberion et al.
999 (1977), TW Campbell, J. Org. Chem., 28, 2069.
(1963), JP-A-51-61599, JP-A-4-
It is disclosed in Japanese Patent Publication No. 261428. The method for synthesizing polycarbodiimide is not particularly limited, but, for example, reacting an organic polyisocyanate in the presence of a catalyst that accelerates a carbodiimidization reaction of an isocyanate group (hereinafter, referred to as “carbodiimidization catalyst”). Thus, polycarbodiimide can be synthesized. As the organic polyisocyanate used for the synthesis of polycarbodiimide, organic diisocyanate is preferable. Examples of such an organic diisocyanate include diphenylmethane-2,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate and 1,3-xylylene diisocyanate. , 1,4-xylylene diisocyanate, phenylene-1,3-diisocyanate, phenylene-1,4-diisocyanate, 1-methoxyphenylene-2,4-diisocyanate, biphenylene-4,4'-diisocyanate, 3,
3'-dimethoxybiphenylene-4,4'-diisocyanate, 3,3'-dimethylbiphenylene-4,4'-
Diisocyanate, 3,3'-dimethoxydiphenylmethane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, naphthylene-1,5-diisocyanate, cyclobutylene-1,3-diisocyanate, cyclo Pentylene-1,
3-diisocyanate, cyclohexylene-1,3-diisocyanate, cyclohexylene-1,4-diisocyanate, 1-methylcyclohexylene-2,4-diisocyanate, 1-methylcyclohexylene-2,6-
Diisocyanate, 1-isocyanate-3,3,5-
Trimethyl-5-isocyanate methylcyclohexane, cyclohexane-1,3-bis (methylisocyanate), cyclohexane-1,4-bis (methylisocyanate), isophorone diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, dicyclohexylmethane-4, 4'-diisocyanate, ethylene diisocyanate, tetramethylene-1,4-diisocyanate, hexamethylene-1,6-diisocyanate, dodecamethylene-1,12-diisocyanate, lysine diisocyanate methyl ester, etc., and stoichiometry of these organic diisocyanates Examples thereof include both-terminal isocyanate prepolymers obtained by the reaction between a specific excess amount and a bifunctional active hydrogen-containing compound. Among these organic diisocyanates, especially diphenylmethane-
4,4'-diisocyanate is preferred. The organic diisocyanates may be used alone or in admixture of two or more.

It is also possible to use other organic polyisocyanates, optionally together with organic diisocyanates, in amounts not exceeding 20 mol% of the total organic polyisocyanate component. Examples of the other organic polyisocyanates include benzene-1,3,5-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, diphenylmethane-2,5,4'-triisocyanate and triphenylmethane-2. , 4 ', 4 "-triisocyanate, triphenylmethane-4,4', 4"-
Triisocyanate, diphenylmethane-2,4
2 ', 4'-tetraisocyanate, diphenylmethane-2,5,2', 5'-tetraisocyanate, cyclohexane-1,3,5-triisocyanate, cyclohexane-1,3,5-tris (methylisocyanate), 3 , 5-Dimethylcyclohexane-1,3,5-
Tris (methylisocyanate), 1,3,5-trimethylcyclohexane-1,3,5-tris (methylisocyanate), dicyclohexylmethane-2,4,2 ′
-Triisocyanate, dicyclohexylmethane-2,
Trifunctional or more trifunctional organic polyisocyanates such as 4,4′-triisocyanate, or a stoichiometric excess of these trifunctional or more polyfunctional polyisocyanates with a difunctional or more polyfunctional active hydrogen-containing compound The terminal isocyanate prepolymer obtained can be mentioned. These other organic polyisocyanates can be used alone or in admixture of two or more.

Further, in the synthesis of polycarbodiimide, the molecular weight of the obtained polycarbodiimide can be appropriately regulated by adding an organic monoisocyanate if necessary. Examples of such organic monoisocyanate include methyl isocyanate, ethyl isocyanate, n-propyl isocyanate, n-
Aliphatic monoisocyanates such as butyl isocyanate, lauryl isocyanate, stearyl isocyanate; alicyclic monoisocyanates such as cyclohexyl isocyanate, 4-methylcyclohexyl isocyanate, 2,5-dimethylcyclohexyl isocyanate;
Phenyl isocyanate, o-tolyl isocyanate,
m-tolyl isocyanate, p-tolyl isocyanate, 2-methoxyphenyl isocyanate, 4-methoxyphenyl isocyanate, 2-chlorophenyl isocyanate, 4-chlorophenyl isocyanate, 2-trifluoromethylphenyl isocyanate, 4-trifluoromethylphenyl isocyanate, naphthalene- 1
-Aromatic monoisocyanates such as isocyanates can be mentioned. The organic monoisocyanates can be used alone or in combination of two or more, and the amount used varies depending on the desired molecular weight of the polycarbodiimide, the presence or absence of the other organic polyisocyanates, and the like. Usually 0 per 100 parts by weight of ingredient
-40 parts by weight, preferably 0-20 parts by weight.

The carbodiimidization catalyst is not particularly limited, and examples thereof include 1-phenyl-2-
Phosphorene-1-oxide, 1-phenyl-3-methyl-2-phosphorene-1-oxide, 1-phenyl-2-
Phosphorene-1-sulfide, 1-phenyl-3-methyl-2-phosphorene-1-sulfide, 1-ethyl-2
-Phospholen-1-oxide, 1-ethyl-3-methyl-2-phospholen-1-oxide, 1-ethyl-2-phospholen-1-sulfide, 1-ethyl-3-methyl-
2-phospholen-1-sulfide, 1-methyl-2-phosphorene-1-oxide, 1-methyl-3-methyl-2
-Phosphorene-1-oxide, 1-methyl-2-phosphorene-1-sulfide, 1-methyl-3-methyl-2-
Phosphorene-1-sulfide and phospholene compounds such as 3-phosphorene isomers thereof; iron pentacarbonyl,
Non-carbonyldiiron, tetracarbonylnickel, hexacarbonyltungsten, hexacarbonylchromium, and other metal carbonyl complexes; beryllium, aluminum, zirconium, chromium, iron, and other metals, acetylacetone complexes; trimethylphosphate, triethylphosphate, triisopropylphosphate, tri- Examples thereof include phosphoric acid esters such as t-butyl phosphate and triphenyl phosphate. The carbodiimidization catalyst is
Can be used alone or in combination of two or more,
The amount used is usually 0.001 to 30 parts by weight, preferably 0.01 to 10 parts by weight, based on 100 parts by weight of the total organic isocyanate component.

The synthesis reaction of polycarbodiimide is usually
It is carried out in a suitable solvent. As the solvent, any solvent may be used as long as it can dissolve polycarbodiimide by heating during the synthesis reaction, for example, 1,1-dichloroethane, 1,2.
-Dichloroethane, 1,1,1-trichloroethane,
1,1,2-trichloroethane, 1,1,1,2-tetrachloroethane, 1,1,2,2-tetrachloroethane, 1,1-dichloroethylene, 1,2-dichloroethylene, trichloroethylene, tetrachloroethylene, chlorobenzene, o- Halogenated hydrocarbon solvents such as dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, 1,2,4-trichlorobenzene and trichloromethylbenzene; dioxane, anisole, tetrahydrofuran, tetrahydropyran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Ether-based solvents such as diethylene glycol dipropyl ether and diethylene glycol dibutyl ether; methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 2- Cetyl cyclohexanone, 2-
Ketone solvents such as methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, cycloheptanone; aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, cumene; N-methyl-2-pyrrolidone, N- Acetyl-2-pyrrolidone, N-methyl-3-pyrrolidone, N-acetyl-3-
Amide solvents such as pyrrolidone, N-methylformamide, N, N-dimethylformamide, N-ethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropionamide. Aprotic polar solvent such as dimethyl sulfoxide; 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2-propoxyethyl acetate, 2-butoxyethyl acetate,
Acetate solvents such as 2-phenoxyethyl acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monopropyl ether acetate, and diethylene glycol monobutyl ether acetate can be mentioned. These solvents can be used alone or in combination of two or more. In the polycarbodiimide synthesis reaction, the solvent is used in such a proportion that the concentration of all organic isocyanate components is usually 0.5 to 60% by weight, preferably 5 to 50% by weight. In this case, if the concentration of all organic isocyanate components is too high,
The resulting polycarbodiimide may gel during the synthesis reaction, and if the concentration of all organic isocyanate components is too low, the reaction rate will be slow and productivity will be reduced.

The temperature of the polycarbodiimide synthesis reaction is
The temperature is usually 20 to 200 ° C., though it is appropriately selected depending on the types of the organic isocyanate component and the carbodiimidization catalyst. In the polycarbodiimide synthesis reaction, the organic isocyanate component may be added in its entirety before the reaction, or a part or all of it may be added continuously or stepwise during the reaction. Further, in the present invention, a compound capable of reacting with an isocyanate group is added at an appropriate reaction stage from the initial stage to the latter stage of the polycarbodiimide synthesis reaction to seal the terminal isocyanate group of the polycarbodiimide to obtain a polycarbodiimide obtained. The molecular weight of the polycarbodiimide can be adjusted, or the molecular weight of the resulting polycarbodiimide can be regulated to a predetermined value by adding it at a later stage of the synthesis reaction of the polycarbodiimide. Examples of the compound capable of reacting with such an isocyanate group include alcohols such as methanol, ethanol, isopropanol and cyclohexanol; amines such as dimethylamine, diethylamine and benzylamine. The polycarbodiimide synthesized as described above is separated from the solution as needed. In this case, as a method for separating polycarbodiimide, for example, a polycarbodiimide solution is added to a non-solvent inert to the polycarbodiimide, and the resulting precipitate or oil is separated and collected by filtration or decantation. Method: Separation / collection by spray drying; Separation / collection using the change in solubility with temperature of the solvent used in the synthesis of the obtained polycarbodiimide, that is, a poly (vinyl chloride) dissolved in the solvent immediately after synthesis When carbodiimide is precipitated by lowering the temperature of the system, a method of separating / collecting the turbid liquid by filtration or the like can be mentioned, and further, these separating / collecting methods can be appropriately combined. The polystyrene reduced number average molecular weight (hereinafter referred to as “Mn”) of the polycarbodiimide obtained by gel permeation chromatography (GPC) of the present invention is usually 400 to 100,000, preferably 1,000 to 50,000. , Particularly preferably 1,000
〜１０10,000.

<Reactive Compound> Next, the reactive compound used for the synthesis of the modified polycarbodiimide is a compound having a graft reactive group and a carboxylic acid anhydride group, and the compound is an aromatic compound. It may be an aliphatic compound or an alicyclic compound, and in the case of a cyclic compound, it may be a carbocyclic compound or a heterocyclic compound. Here, the graft reactive group means a group capable of reacting with polycarbodiimide to give a modified polycarbodiimide grafted with a reactive compound residue having a carboxylic acid anhydride group. Such a graft-reactive group may be a functional group having active hydrogen, and examples thereof include a carboxyl group or a primary or secondary amino group. In the reactive compound, these graft-reactive groups may have one or more identical or different groups and one or more carboxylic acid anhydride groups. Examples of the reactive compound include trimellitic anhydride, benzene-1,2,3-tricarboxylic anhydride, naphthalene-1,2,4-tricarboxylic anhydride,
Naphthalene-1,4,5-tricarboxylic acid anhydride, naphthalene-2,3,6-tricarboxylic acid anhydride, naphthalene-1,2,8-tricarboxylic acid anhydride, 4- (4-carboxybenzoyl) phthalic acid anhydride , 4- (4-carboxyphenyl) phthalic anhydride, 4- (4-carboxyphenoxy) phthalic anhydride, and other aromatic tricarboxylic anhydrides: 3-carboxymethyl glutaric anhydride,
Butane-1,2,4-tricarboxylic acid-1,2-anhydride, propene-1,2,3-tricarboxylic acid-1,2-
Aliphatic tricarboxylic acid anhydrides such as anhydrides; 3-amino-4-cyano-5-methylphthalic anhydride, 3-amino-4-cyano-5,6-diphenylphthalic anhydride, 3
-Amino aromatic dicarboxylic acid anhydrides such as methylamino-4-cyano-5-methylphthalic anhydride and 3-methylamino-4-cyano-5,6-diphenylphthalic anhydride; aminosuccinic anhydrides, 4 -Amino-1,2-butanedicarboxylic anhydride, 4-aminohexahydrophthalic anhydride, N-methylaminosuccinic anhydride, 4-methylamino-1,2-butanedicarboxylic anhydride, 4-methyl Mention may be made of aminoaliphatic dicarboxylic acid anhydrides such as aminohexahydrophthalic anhydride. Among these reactive compounds, trimellitic anhydride is particularly preferred. The reactive compounds can be used alone or in combination of two or more.

<Synthesis of Modified Polycarbodiimide> Next,
A method for synthesizing the modified polycarbodiimide will be described. The modified polycarbodiimide is obtained by adding at least one reactive compound to at least one polycarbodiimide having a repeating unit represented by the general formula (1) at a suitable temperature in the presence or absence of a suitable catalyst. It can be synthesized by grafting (hereinafter, referred to as "modification reaction"). The amount of the reactive compound used in the modification reaction is appropriately adjusted according to the type of the compound or polycarbodiimide, the specific application of the resin composition, etc., but the repeating unit represented by the general formula (1) of polycarbodiimide is used. With respect to 1 mol, the graft reactive group in the reactive compound is usually
It is used in an amount of 0.01 to 1 mol, preferably 0.02 to 0.8 mol. In this case, if the proportion of graft-reactive groups is less than 0.01 mol, it may be necessary to heat the resin composition for a long period of time, and if it exceeds 1 mol, polycarbodiimide's original content may be exceeded. The characteristics may be impaired. In the modification reaction, the reaction between the graft-reactive group in the reactive compound and the repeating unit represented by the general formula (1) of polycarbodiimide proceeds quantitatively, and the graft amount corresponding to the amount of the reactive compound used. Is obtained. The modification reaction can be carried out in the absence of a solvent, but it is preferably carried out in a suitable solvent. Such a solvent is inert to the polycarbodiimide and the reactive compound, and as long as it can dissolve these,
It is not particularly limited, and examples thereof include the ether-based solvent used in the synthesis of polycarbodiimide,
Amide solvent, ketone solvent, aromatic hydrocarbon solvent,
An aprotic polar solvent etc. can be mentioned. These solvents can be used alone or in combination of two or more. When the solvent used in the synthesis of the polycarbodiimide can be used for the modification reaction, the polycarbodiimide solution obtained by the synthesis can be used as it is. The amount of the solvent used in the modification reaction is usually 10 to 10 per 100 parts by weight of the total amount of the reaction raw materials.
000 parts by weight, preferably 50 to 5,000 parts by weight. The temperature of the modification reaction is appropriately selected according to the type of polycarbodiimide or reactive compound, but is usually 100 ° C.
Hereinafter, it is preferably −10 to + 80 ° C. The Mn of the modified polycarbodiimide obtained as described above is usually 500 to 200,000, preferably 1,000 to
100,000, more preferably 1,000-50,
000. The modified polycarbodiimide obtained as described above is usually separated from a solution and used as a polymer powder. As a method of separating the modified polycarbodiimide obtained as a solution at the time of synthesis from the solvent, the same method as the above-mentioned separation method of polycarbodiimide can be mentioned. The modified polycarbodiimide in the present invention is a residue having a carboxylic acid anhydride group of the compound in which the grafting reactive group in the reactive compound reacts with the repeating unit of polycarbodiimide (-N = C = NR ^1- ). Has a grafted structure, and has a structure essentially different from that of the polycarbodiimide before the modification reaction. Therefore, the modified polycarbodiimide has different properties from the polycarbodiimide before the modification reaction, and by mixing with an epoxy resin and heating, the curing catalyst is used by the action of the carboxylic acid anhydride group in the modified polycarbodiimide. Even if not, it is usually 100 to 350 ° C., preferably 15
It has the property of being easily cured at a temperature of 0 to 300 ° C.

(B) Epoxy Resin The epoxy resin in the present invention is not particularly limited as long as it is a compound having two or more epoxy groups in the molecule, and examples thereof include biphenyl type epoxy resin and naphthalene type epoxy resin. , Phenol novolac type epoxy resin, orthocresol novolac type epoxy resin,
Bisphenol A type epoxy resin, bisphenol F type epoxy resin, dicyclopentadiene-phenol polyaddition type epoxy resin, linear aliphatic epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, halogenated epoxy resin, etc. You can These epoxy resins may be used alone or in combination of two or more. The compounding amount of the epoxy resin in the present invention is such that the total carbodiimide group in the polycarbodiimide before the modification reaction is 0.05 to 1 equivalent of the epoxy group in the epoxy resin.
A ratio of 1.5 equivalents is preferable, and 0.1 to 1.0 is particularly preferable.
The equivalent ratio is preferable. In this case, if the total carbodiimide groups are less than 0.05 equivalents, the solder heat resistance and flame retardancy of the cured product tend to decrease, and if it exceeds 1.5 equivalents, the moldability of the resin composition tends to decrease. There is.

(C) Filler As the filler in the present invention, for example, amorphous silica,
Examples thereof include crystalline silica, calcium carbonate, magnesium carbonate, calcium silicate, silicon nitride, silicon carbide, antimony oxide, titanium oxide, alumina, magnesia, clay, talc, glass fiber, ceramic fiber and whiskers. Among these fillers, amorphous silica is preferable because it has a large effect of lowering the thermal expansion coefficient of the resin composition after curing. The shape and particle size of the filler are not particularly limited, but the average particle size is 30 μm from the viewpoint of moisture resistance and fluidity.
Spherical amorphous silica of m or less is preferable. Further, the filler is used by surface treatment in advance with a coupling agent such as a silane coupling agent or a titanate coupling agent, or is used in combination with these coupling agents, as has been conventionally practiced. However, it is preferable from the viewpoint of improving reliability as a semiconductor sealing material. As such a coupling agent, for example, a silane coupling agent having a functional group such as an epoxy group, an amino group, a mercapto group, a (meth) acryloyl group and a vinyl group is preferable. The compounding amount of the filler in the present invention is 60 to 95% by weight, preferably 80 to 95% by weight of the total resin composition. In this case, if the compounding amount of the filler is less than 60% by weight, the effect of lowering the thermal expansion coefficient and water absorption of the cured product becomes insufficient,
If the solder crack resistance is reduced, and if it exceeds 95% by weight, the viscosity of the resin composition is increased and the moldability is impaired.

Furthermore, in the resin composition for encapsulating a semiconductor of the present invention, if necessary, for example, a coloring agent, a release agent, a stress reducing agent, an antioxidant, a heat stabilizer, an antistatic agent, and an adhesive agent. Other additives such as a sex improving agent and an antifungal agent can also be added. Examples of the colorant include carbon black and iron oxide, and examples of the release agent include long-chain fatty acids, metal salts of long-chain fatty acids, amides of long-chain fatty acids, and esters of long-chain fatty acids. Paraffin wax can be used, and examples of the stress reducing agent include modified nitrile rubber, modified polybutadiene rubber, silicone rubber, modified silicone oil, and the like. The blending amount of these additives may be the same as the blending amount in the conventional epoxy resin composition for semiconductor encapsulation. The resin composition for semiconductor encapsulation of the present invention has essentially high flame retardancy without blending a flame retardant or a flame retardant auxiliary agent, but especially for applications requiring flame retardancy. When used, blending a flame retardant or a flame retardant aid in order to further improve the reliability as a semiconductor encapsulating material does not depart from the gist of the present invention. Examples of such flame retardants include halogen compounds, phosphorus compounds, reactive flame retardants and the like, and examples of flame retardant aids include antimony trioxide and the like. The blending amount of these flame retardant and flame retardant auxiliary is less than the blending amount in the conventional epoxy resin composition for semiconductor encapsulation. The resin composition for semiconductor encapsulation of the present invention has excellent curing properties by itself, but if desired, the carbodiimide group and / or acid anhydride group in the (A) modified polycarbodiimide or the (B) epoxy can be used. A compound having reactivity with the epoxy group in the resin and having an action of promoting the curing reaction of the resin composition can be further added. Examples of such compounds include compounds having basic active hydrogen such as dicyandiamide and organic acid dihydrazide, tertiary amine compounds, tertiary amine salt compounds, quaternary ammonium salt compounds, and imidazole compounds. You can The compounding amount of these compounds is preferably in the range of 0.1 to 5 parts by weight per 100 parts by weight of the modified polycarbodiimide. The resin composition for semiconductor encapsulation of the present invention comprises (A) modified polycarbodiimide, (B) epoxy resin and (C).
Fillers, optionally with other additives,
For example, use a mixer to mix evenly, and
For example, by melting and kneading using a known kneading device such as a heat roll, a Banbury mixer, a kneader, a single-screw or twin-screw extruder, and then cooling and solidifying the mixture, the semiconductor is sealed by crushing into an appropriate size. Can be prepared in the form of a molding material powder suitable for. In this case, the particle size of the powder may be the same as the particle size in the conventional epoxy resin composition for semiconductor encapsulation. The method for sealing a semiconductor using the resin composition for semiconductor encapsulation of the present invention thus obtained is not particularly limited, and a known molding method,
For example, a low pressure transfer molding method, an injection molding method, a compression molding method, a casting method or the like can be adopted. The molding temperature during semiconductor encapsulation is usually 150 to 200 ° C.,
The post-curing condition after molding is 170 to 220.
Preferred is 1 to 10 hours at ° C.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to these examples as long as the gist thereof is not exceeded. Here,% and parts are based on weight unless otherwise specified. Synthesis Example 1 After the inside of a separable flask having an inner volume of 500 ml was replaced with nitrogen, 277 g of toluene was added. Then diphenylmethane-4,4'-diisocyanate (M
DI) 60.6 g and phenyl isocyanate (PhI)
3.13 g was added and stirred with a stirrer to give a uniform solution. To this solution was added 3 as a carbodiimidization catalyst.
-Methyl-1-phenyl-3-phosphorene-1-oxide (46.5 mg) was added, the temperature was raised to about 110 ° C with stirring, and toluene was refluxed to start the reaction. After reacting for 5 hours, the temperature of the reaction system was cooled to 80 ° C. After that, 4.85 g of trimellitic anhydride dissolved in 19.4 g of acetone was added dropwise over 30 minutes as a reactive compound. After continuing the reaction for another 30 minutes, 250 g of acetone was gradually added, and the precipitated polymer powder was collected by vacuum filtration and dried under reduced pressure at 40 ° C. overnight to 49.4.
g of modified polycarbodiimide powder was obtained. The Mn of this modified polycarbodiimide was 3,900.

[0018]

【Example】

Examples 1 to 4 The modified polycarbodiimide obtained in Synthesis Example 1 and the resin composition of the formulation shown in Table 2 using the epoxy resin shown in Table 1 were thoroughly mixed with a mixer, and then the roll surface temperature was 100 to 120 ° C. It melt-kneaded for 10 minutes using the hot roll of. Then, it cooled and grind | pulverized and obtained the resin composition powder. Then, using these resin composition powders, 175 ° C.
Perform low pressure transfer molding under molding conditions of × 4 minutes,
After molding a QFP package (52 pins, chip size 6 × 6 mm) encapsulating the simulated element, post-curing was performed at 175 ° C. for 6 hours to fabricate a test element.
Using these test devices, solder heat resistance and flame retardancy were evaluated by the following procedures. Table 2 shows the evaluation results. Solder heat resistance: 20 test elements were humidified for 72 hours in an environment of 85 ° C x 85% relative humidity, and then 260 ° C
It was dipped in the solder bath for 10 seconds and evaluated by the number of test elements in which cracks occurred. Flame retardance: evaluated according to UL-94 standard.

Comparative Examples 1 to 4 The resin compositions having the formulation shown in Table 2 were thoroughly mixed by a mixer and then melt-kneaded for 10 minutes using a hot roll having a roll surface temperature of 80 to 100 ° C. Then, it cooled and grind | pulverized and obtained the resin composition powder. Next, using these resin composition powders, a test element was prepared and evaluated in the same manner as in Examples 1 to 4. Table 2 shows the evaluation results.

[0020]

[Table 1]

[0021]

[Table 2]

[0022]

EFFECT OF THE INVENTION The resin composition for semiconductor encapsulation of the present invention is excellent in solder crack resistance and can reduce the amount of the flame retardant or flame retardant auxiliary agent used. It can be manufactured without problems in environmental protection and safety.

Claims (1)

[Claims] 1. A resin comprising (A) a polycarbodiimide grafted with at least one compound having a graft reactive group and a carboxylic acid anhydride group, (B) an epoxy resin and (C) a filler. A resin composition for semiconductor encapsulation, wherein the content of the filler is 60 to 95% by weight of the total resin composition.