JPH06122765A - Resin composition for semiconductor encapsulation - Google Patents

Abstract

(57) [Summary] [Purpose] Polymaleimide resins, which have better heat resistance than epoxy resins, generally have poor moldability and low strength. The purpose is to improve the properties of this polymaleimide resin as a semiconductor encapsulant. [Structure] The resin composition of the present invention comprises: Polymaleimide, B.I. An allylphenol compound having two or more allyl groups in the molecule, C.I. A polyaminosiloxane having a specific structure, D.I. Silica, E.I. It is characterized in that five components of the organoalkoxysilane compound having an amino group are essential components. [Effect] According to the resin composition containing the above-mentioned five components A to E as essential components, it is possible to obtain a cured product having excellent molding processability, particularly fluidity, and high mechanical strength. Further, the effect of lowering the elastic modulus due to the addition of silica is sufficiently exhibited without lowering the heat resistance, and it is extremely useful as a resin composition for semiconductor encapsulation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for semiconductor encapsulation, which is a polymaleimide resin having high heat resistance, which gives a cured product having excellent fluidity and curing characteristics during molding and high bending strength. It relates to a composition.

[0002]

2. Description of the Related Art Hitherto, many epoxy resins have been used as thermosetting resins. However, in recent years, the use conditions for molded articles have become increasingly severe, and as a result, it has become increasingly difficult for epoxy resins to satisfy all the properties. A polymaleimide resin is well known as a thermosetting resin having higher heat resistance than an epoxy resin, but in general, the polymaleimide resin has a high melting point or softening temperature, and it has been difficult to say that the moldability is good. Further, the obtained cured product had a high elastic modulus and a small elongation at break, so the strength was low, and as a result, only a brittle product was obtained.

As an example in which the characteristics of a resin cured product are improved by mixing a maleimide resin and an allylphenol type compound, a thermosetting polymaleimide resin and o, o '
-Regarding a resin composition with diallyl bisphenol A, published patent publication No. 55-39242, for a composition with a bismaleimide compound and a diallyl ether compound of bisphenol S, published patent publication No. 53-134099,
The composition of a bismaleimide compound and an allyl ether of phenol novolac is disclosed in JP-A-62-62.
No. -11716 is known. Furthermore, IC, L
In order to reduce the thermal stress on the surface of SI, it is known to add silica having a low coefficient of thermal expansion for plastic encapsulation, and a resin composition developed for silica encapsulation by adding silica to a bismaleimide compound. For example, JP-A-63-230728 and the like are known.

[0004]

However, in the above-mentioned Japanese Patent Laid-Open No. 63-230728, what kind of surface treatment agent is suitable is not concretely shown in the examples. Further, in the composition of polymaleimide and aminopolysiloxane, Japanese Patent Application Laid-Open No. 22222419/1990.
Although the examples of No. 1 are known, only the description of the direct reaction between polymaleimide and aminopolysiloxane is given, and addition of additives is not described.

As described above, in the plastic encapsulant for semiconductors, it is necessary to blend silica having a low coefficient of thermal expansion in order to reduce the thermal stress. It is expected that the fluidity of the obtained resin composition at the time of molding is lowered, and desired molding cannot be sufficiently performed. Moreover, since the resin component decreases relative to each other, the mechanical strength may decrease.

Therefore, in the production of a resin composition for semiconductor encapsulation containing silica, the characteristics as an encapsulant are excellent under a sufficient silica content without impairing the fluidity and curing characteristics of the composition. It is necessary to obtain such a resin composition, but such a study has not been made in the past, and the improvement is desired. The present invention has been made in view of the conventional circumstances described above, and is a polymaleimide resin composition useful as a semiconductor encapsulant capable of obtaining a cured product having excellent fluidity and curing characteristics and a low elastic modulus. The purpose is to provide.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a polymaleimide compound,
An allyl-phenol compound having two or more allyl groups in the molecule, a polyaminosiloxane, silica, and an organoalkoxysilane compound having an amino group are essential components, and by mixing these in specific amounts, the fluidity is excellent and the curing characteristics are high. The present invention has been accomplished by finding a resin composition that gives a cured product having excellent strength and high strength.

That is, the gist of the present invention is as follows.
It exists in a resin composition for semiconductor encapsulation containing B, C, D and E components as essential components. A. Polymaleimide B. Allylphenol compounds having two or more allyl groups in the molecule C.I. Polyaminosiloxane represented by the following general formula (1)

[0009]

[Chemical 2]

(R in (Formula 1)¹Is CH₃, C₆H_Five, R
^FourNH₂(R^FourIs an alkylene group), and R
²Is R^FiveNH₂, R^FiveNHR⁶NH₂, CH₃, C₆H
_Five(R ^Five, R⁶Is an alkylene group) and R
¹Or R²At least one of which has an amino group, R³Is
CH₃, C₆H_Five, And m is an integer greater than or equal to 1
And n represents an integer of 0 or more) D. Silica and E.I. Organoalkoxysilane Compound Having Amino Group Details of the present invention are described below.

The polymaleimide which is the component A used in the present invention is a polymaleimide compound represented by the following general formula (2) and having two or more maleimide groups in the molecule. In the following general formula (2), n represents an integer of 2 or more, and Y represents a divalent or higher polyvalent residue. Y may be aliphatic, aromatic, alicyclic, or heterocyclic as long as it is a divalent or higher polyvalent residue, but it is preferably aromatic.

[0012]

[Chemical 3]

The component A used in the present invention can be easily obtained by reacting a diamine or polyamine with maleic anhydride. Here, the diamine is represented by the general formula (H ₂ N) ₂ Y (Y
Is a compound which is the same as Y in formula (2) and represents a divalent residue). Specific examples of the bismaleimide compound obtained by the reaction of such a diamine and maleic anhydride include aliphatic bismaleimides such as 1,2-dimaleimideethane and 1,3-dimaleimidepropane, and bis (4 -Maleimidophenyl) methane, bis (3
-Ethyl-4-maleimidophenyl) methane, bis (3
-Ethyl-4-maleimido-5-methylphenyl) methane, 2,7-dimaleimidofluorene, 1,3-dimaleimidobenzene, 1,4-dimaleimidobenzene, 2,
4-dimaleimidotoluene, bis (maleimidophenyl) sulfone, bis (maleimidophenyl) ether,
2,2-bis (4- (4-maleimidophenoxy) phenyl) propane, bis (4- (4-maleimidophenoxy) phenyl) sulfone, 1,3-bis (2- (3-maleimidophenyl) propyl) benzene ( Aromatic bismaleimides such as etc., alicyclic bismaleimides such as 1,4-dimaleimidocyclohexane, heterocycles such as bis (maleimidophenyl) thiophene (including isomers), etc. Formula bismaleimide etc. can be illustrated. The bismaleimide compound used in the present invention is preferably aromatic bismaleimide from the viewpoint of heat resistance. On the other hand, as the polyamine, the general formula (H ₂ N) _n Y
(N is an integer of 3 or more, and Y is the same as Y in the general formula (2) and represents a trivalent or higher valent residue). Specific examples of the polymaleimide compound obtained by the reaction of polyamine and maleic anhydride include maleimide compounds of polycondensates of aniline or its derivative and formalin.

An example is an adduct obtained by reacting the various polymaleimide compounds obtained above with an aromatic diamine or an aliphatic diamine so that the maleimide functional group remains. Furthermore, it is also possible to use two or more of these polymaleimide compounds in combination, or to mix the above diamines or polyamines to form maleimides and use them as a mixture of polymaleimide compounds. Monomaleimide can be added within a range that does not impair the fluidity and moldability.

The component B of the present invention is an allylphenol compound having two or more allyl groups in the molecule. In order to smoothly mix with the polyaminosiloxane which is the C component, the B component is preferably liquid. Even if it is solid at room temperature, it may be liquid when heated. Specifically, 2,2-bis (3-allyl-4-hydroxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3-allyl-4-hydroxy) Examples thereof include phenyl) propane, bis (3-allyl-4-hydroxyphenyl) sulfone, bis (3-allyl-4-hydroxyphenyl) sulfide, and bis (3-allyl-4-hydroxyphenyl) ether. Furthermore, it is also possible to use two or more of these in combination.

In the present invention, the allyl group of the allylphenol compound is 0.5 to 1. per 1 equivalent of the maleimide functional group of the polymaleimide compound (component A) having two or more maleimide groups in the molecule. It is preferably in the range of 5 equivalents. When the amount of allyl groups is less than 0.5 equivalent, the obtained molded product becomes brittle, and when it is more than 1.5 equivalents, the heat resistance decreases.

The C component used in the present invention is a polyaminosiloxane having amino groups at both ends of the molecule or having aminosiloxane in a part of the siloxane main chain, and its structure is represented by the above general formula (1). C like this
The average molecular weight of the component is not a factor that affects the characteristics of the obtained composition, but a preferable range is 500 or more and 5000 or less. Further, it is necessary to have an amino group in the molecule, and when polysiloxane having no amino group is used as the C component, the elastic modulus of the cured product is high, and the effect of stress relaxation on heat shrinkage is I can't.

The component C has a composition ratio of 10 parts by weight or more and 5 parts by weight or more with respect to 100 parts by weight of the polymaleimide as the component A.
It is preferably 0 parts by weight or less. If the amount of this C component is less than 10 parts by weight, the elastic modulus of the cured product is high, and as a result, the stress against heat shrinkage that occurs during cooling when the molded product is taken out becomes large, and the metal lead frame and silicon chip. It may cause peeling at the interface with the chip or cause defects in the chip itself. On the other hand, when the content of the component C exceeds 50 parts by weight, the strength of the cured product is remarkably lowered and a satisfactory product is not provided.

The component D of the present invention is not particularly limited as long as it is silica. Silica is classified into shapes such as prismatic, spherical, manufacturing method, crushed, synthetic, vapor phase manufacturing, etc., but when using multiple groups of silica with different average particle sizes, mix with other materials. It is also possible to previously mix only silica with each other. At that time, silica having an average particle diameter of 0.01 μ to 150 μ can be used.
Silica is 20 to 95% by volume of the entire resin composition obtained.
Preferably from 60 to 90
% By volume. If the silica filling rate is less than 20% by volume, the effect of lowering the coefficient of thermal expansion is insufficient, and if the filling rate exceeds 95% by volume, the fluidity required for molding cannot be secured.

Further, as the filler other than silica, other inorganic fillers, reinforcing fibers and the like can be added. Specific examples thereof include alumina powder, mica, titania, zirconia, glass fiber, carbon fiber, aramid fiber, and holon fiber. The component E of the present invention may be any organoalkoxysilane compound having an amino group. Generally, it has one or two organic groups having an amino group and two alkoxy groups as a substituent of silicon.
It is a silane compound having one or three. The silicon atom in the molecule may have these substituents as essential,
There is no problem with the number.

A methoxy group or an ethoxy group is preferably used as the alkoxy group. Specifically, 3-aminopropyltriethoxysilane, 3- (N-allyl-N-
(2-Aminoethyl)) aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-
Examples include aminopropylmethyldimethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane. The amount to be added is often determined according to the surface properties of silica to be used, but it is generally used in the range of 0.1 to 5 grams, preferably 0.5 to 3 grams per 100 grams of silica. Used in.
The addition method may be such that it is added to the silica in advance, or it may be added when the silica is mixed as the resin component.

The mixing method of each component is not particularly limited, but it is preferable that the mixing temperature does not exceed 90 ° C. As the mixer, specifically, a heat roll, an extruder,
A kneader, a mixer and the like are generally mentioned. It is pointed out that even if the semiconductor is sealed, the impurities in the sealing material may rather destroy the memory and cause a malfunction. It is said that this cause is caused by radioactive elements such as uranium and thorium which are the α-ray source contained in the encapsulating material, and therefore it is desirable that the number of such elements is small.

Further, if necessary, dicumyl peroxide, butyl levulinate tertbutylperoxyketal, 1,4-bis (2- (2- (tert-butylperoxy) propyl)) benzene and the like are usually used in this field. Organic peroxides, amine compounds, curing accelerators such as imidazole compounds and phosphine compounds, natural waxes, synthetic waxes, internal release agents such as organic fatty acids and their esters or metal salts, brominated epoxy compounds and brominated It is possible to add flame retardants such as halogen compounds such as phenol compounds and antimony oxide, colorants such as carbon black, and functional modifiers such as flexibility-imparting agents such as nitrile rubber and silicone compounds other than polyaminosiloxane. .

The resin composition thus obtained has a low coefficient of thermal expansion without lowering the heat resistance, has a good adhesion to a metal, has a good fluidity, and has a mechanical property of a cured product. It has a high dynamic strength and is suitable as a resin for semiconductor encapsulation.

[0025]

EXAMPLES The present invention will be described in more detail with reference to examples. Synthesis example : Bis (4-maleimidophenyl) methane 100
Gram, 27.7 g of bis (4-aminophenyl) methane, was heated in 200 ml of dimethylformamide (DMF) at 120 ° C. for 30 minutes, poured into water, and the obtained precipitate was filtered and dried to obtain an adduct A. 120.2 grams was obtained. The vinyl proton of maleimide was confirmed by the nuclear magnetic resonance method.

Example 1 31.0 grams of bis (4-maleimidophenyl) methane, 25.8 grams of 2,2-bis (3-allyl-4-hydroxyphenyl) propane, and 7.7 grams of adduct A. Was added, heated at 150 ° C. for 20 minutes, stirred, and cooled, and then 336 g of spherical silica having an average particle size of 18 μ, 84 g of crushed silica having an average particle size of 7 μ, 4.2 g of 3-aminopropyltriethoxysilane, an average of A polydimethylsiloxane having a molecular weight of 3000 and having an amino group at the end (in the formula (1) in the specification, R
¹ = (CH ₂ ) ₃ NH ₂ , R ² = R ³ = CH ₃ , m + n
= 38 (calculated from average molecular weight)) 6.5 g, butyl levulinate tert butyl peroxyketal 1.3
Gram, 1,4-bis (2- (2- (tert-butylperoxy) propyl)) benzene 0.3 g, carnauba wax 0.7 g, carbon black having a primary particle size of 20 μ, 0.6 g, A resin composition was obtained by mixing 0.3 g of antimony trioxide, and 1.6 g of a tetrabromobisphenol A type epoxy resin having an epoxy equivalent of 340 and a bromine content of 47% at 75 ° C. for 30 minutes. The composition has a temperature of 180 ° C. and a molding time of 3
Transfer molding was carried out under the condition of minutes to obtain a resin cured product. The fluidity of the obtained resin composition and the bending strength of the cured product were measured.

Example 2 : 29.7 g of bis (4-maleimidophenyl) methane, 24.7 g of 2,2-bis (3-allyl-4-hydroxyphenyl) propane and 7.4 g of adduct A. Was added, and the mixture was heated at 150 ° C. for 20 minutes, stirred, and cooled, and then 336 g of spherical silica having an average particle size of 18 μ, 84 g of crushed silica having an average particle size of 7 μ, 4.2 g of γ-aminopropyltriethoxysilane, an average of 9.3 g of polydimethylsiloxane having a molecular weight of 3000 and having an amino group at the end, 1.2 g of butyl levulinate tert-butyl peroxyketal,
1,4-bis (2- (2- (tert-butylperoxy) propyl)) benzene 0.3 g, carnauba wax 0.6 g, carbon black having a primary particle size of 20 μ 0.6 g, trioxide A resin composition was obtained by mixing 0.3 g of antimony and 1.6 g of a tetrabromobisphenol A type epoxy resin having an epoxy equivalent of 340 and a bromine content of 47% with a two-roll mill at 75 ° C. for 30 minutes. It was molded in the same manner as in Example 1 and its physical properties were measured.

Example 3 Example 3 except that 378 g of spherical silica having an average particle size of 18 μ in Example 2 and 42 g of spherical silica having an average particle size of 1 μ were used instead of crushed silica having an average particle size of 7 μ. A resin composition was obtained in the same manner as in 2. It was molded in the same manner as in Example 1 and the physical properties were measured.

Example 4 : Instead of 3-aminopropyltriethoxysilane in Example 1, 3- (N-allyl-
A resin composition was obtained in the same manner as in Example 1 except that N- (2-aminoethyl)) aminopropyltrimethoxysilane was used. It was molded in the same manner as in Example 1 and the physical properties were measured.

Comparative Example 1 : Example 1 except that 3-glycidoxypropyltrimethoxysilane was used instead of 3-aminopropyltriethoxysilane in Example 1.
A resin composition was obtained in the same manner as above, and the physical properties were measured. The contents of the compositions of Examples 1 to 4 and Comparative Example 1 are shown in Table 1.
In addition, Table 2 shows the physical properties of the obtained resin composition and cured product. As is clear from Table 2, the resin composition according to the present invention is excellent in fluidity at the time of molding and properties of a cured product obtained therefrom.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

EFFECTS OF THE INVENTION According to the resin composition of the present invention containing the components A to E as essential components, it is possible to obtain a cured product having excellent molding processability, particularly fluidity, and high mechanical strength.
Further, the effect of lowering the elastic modulus due to the addition of silica is sufficiently exhibited without lowering the heat resistance, and it is extremely useful as a resin composition for semiconductor encapsulation.

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[Procedure amendment]

[Submission date] November 20, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

Example 1 31.0 grams of bis (4-maleimidophenyl) methane, 25.8 grams of 2,2-bis (3-allyl-4-hydroxyphenyl) propane, and 7.7 grams of adduct A. Was added, heated at 150 ° C. for 20 minutes, stirred, and cooled, and then 336 g of spherical silica having an average particle size of 18 μ, 84 g of crushed silica having an average particle size of 7 μ, 4.2 g of 3-aminopropyltriethoxysilane, an average of A polydimethylsiloxane having a molecular weight of 3000 and having an amino group at the end (in the formula (1) in the specification, R
¹ = (CH ₂ ) ₃ NH ₂ , R ² = R ³ = CH ₃ , m + n
= 38 (calculated from average molecular weight)) 6.5 g, butyl levulinate tert butyl peroxyketal 1.3
Gram, 1,4-bis (2- (2- (tert-butylperoxy) propyl)) benzene 0.3 g, carnauba wax 0.7 g, carbon black having a primary particle size of 20 nm 0.6 g , Antimony trioxide 0.3
Gram and epoxy equivalent 340, bromine content 47%
A resin composition was obtained by mixing 1.6 g of tetrabromobisphenol A type epoxy resin with a two-roll mill at 75 ° C. for 30 minutes. This composition was transfer molded under the conditions of a temperature of 180 ° C. and a molding time of 3 minutes to obtain a resin cured product.
The fluidity of the obtained resin composition and the bending strength of the cured product were measured.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

Example 2 : 29.7 g of bis (4-maleimidophenyl) methane, 24.7 g of 2,2-bis (3-allyl-4-hydroxyphenyl) propane and 7.4 g of adduct A. Was added, and the mixture was heated at 150 ° C. for 20 minutes, stirred, and cooled, and then 336 g of spherical silica having an average particle size of 18 μ, 84 g of crushed silica having an average particle size of 7 μ, 4.2 g of γ-aminopropyltriethoxysilane, an average of 9.3 g of polydimethylsiloxane having a molecular weight of 3000 and having an amino group at the end, 1.2 g of butyl levulinate tert-butyl peroxyketal,
1,4-bis (2- (2- (tert-butylperoxy) propyl)) benzene 0.3 g, carnauba wax 0.6 g, carbon black having a primary particle size of 20 nm 0.6 g, three 0.3 g of antimony oxide,
And epoxy equivalent 340, bromine content 47% tetrabromobisphenol A type epoxy resin 1.6 g 2
A resin composition was obtained by mixing with a main roll at 75 ° C. for 30 minutes. It was molded in the same manner as in Example 1 and its physical properties were measured.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

[0031]

[Table 1]

Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location C08L 29/10 LGZ 6904-4J 83/08 LRY 8319-4J H01L 23/29 23/31

Claims (1)

[Claims] 1. A. Polymaleimide B. Allylpheno having two or more allyl groups in the molecule
Compound C.I. Polyaminosiloxane represented by the following general formula (1):(R in (Formula 1)¹Is CH₃, C₆H_Five, R^FourNH₂(R
^FourIs an alkylene group), and R²Is R^FiveNH
₂, R^FiveNHR⁶NH₂, CH₃, C₆H_Five(R ^Five, R
⁶Is an alkylene group) and R¹Or R²of
At least one has an amino group, R³Is CH₃, C₆
H_Five, M is an integer of 1 or more, and n is
Indicates an integer of 0 or more) D. Silica E. Resin composition for semiconductor encapsulation containing an organoalkoxysilane compound having an amino group as an essential component