JP2002249550A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin composition having properties which excel in storage stability at normal temperatures, moldability, mold release characteristics, flame retardance and soldering stress resistance. SOLUTION: The semiconductor sealing epoxy resin composition comprises, as the essential components, (A) epoxy resins which are (a) a glycidyl etherified product of 4,4'-dihydroxy-3,3',5,5'-tetramethylbiphenyl and (b) a glycidyl etherified product of bis(3,5-dimethyl-4-hydroxyphenyl)methane, (B) a phenolic resin to be represented by formula (1) (wherein n is a mean value and an positive number of 1-10), (C) a whole inorganic substance, (D) a curing accelerator, and (E) a urethane product of an oxidized microcrystalline wax and a urethane product of an oxidized polyethylene wax.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition for semiconductor encapsulation having excellent room temperature storage properties, moldability and mold release properties, and a semiconductor device having excellent flame retardancy and solder stress resistance.

[0002]

2. Description of the Related Art Conventionally, semiconductor devices such as diodes, transistors, and integrated circuits are mainly sealed with an epoxy resin composition. These epoxy resin compositions usually impart flame retardancy. For this purpose, a bromine-containing organic compound and an antimony compound such as antimony trioxide and antimony tetroxide are usually blended. However, development of an epoxy resin composition excellent in flame retardancy without using a bromine-containing organic compound and an antimony compound is desired from the viewpoint of environment and hygiene. In addition, when a semiconductor device is mounted on a printed circuit board, lead-containing solder (tin-lead alloy) is used. Similarly, lead-containing solder (tin-lead alloy) is used from the viewpoint of environment and sanitation. It is desired not to use. The melting point of solder containing lead (tin-lead alloy) is 183 ° C
The soldering temperature during mounting is 220 to 240 ° C. On the other hand, a lead-free solder typified by a tin-silver alloy has a high melting point and a temperature of 260 ° C.
Since the temperature is about ℃, development of an epoxy resin composition having more excellent soldering stress resistance is desired.

In order to improve flame retardancy and solder stress resistance, it is necessary to increase the amount of an inorganic filler and reduce the content of a resin component. One of the methods is to use a low-viscosity resin. is there. At present, an epoxy resin composition using a low-viscosity resin without using a flame retardant and highly filled with an inorganic filler, an epoxy resin composition using a resin with high flame retardancy, and an epoxy resin using various flame retardants Although a composition has been proposed, an epoxy resin composition which completely satisfies good moldability or solder stress resistance has not been proposed yet. This is because a low-viscosity resin is generally a low-molecular-weight compound. Therefore, the cross-linking density of a cross-linked structure obtained by heating during molding becomes low, resulting in a cured product having low mechanical strength and a low elastic modulus when heated. Therefore, when the mold is released from the mold, the cured product is inferior in moldability and mold releasability, such as adhesion of the cured product to the mold or cracking or chipping of the molded product. Furthermore, in the step of sealing a semiconductor device with an epoxy resin composition, it is required to shorten the molding time as one of means for improving production efficiency. For this purpose, quick curing and high mold release during molding are required. When a conventional curing accelerator is added in an amount sufficient to achieve rapid curing at the time of molding, there is a problem that the storage stability of the epoxy resin composition at room temperature is extremely reduced. In addition, in the case of a conventionally used release agent, when a sufficient amount is added to improve the releasability,
Mold fogging due to a large amount of release agent adhering to the mold side,
There was a problem of deterioration in moldability, such as mold removal, and it was not always satisfactory. For this reason, there has been a demand for an epoxy resin composition having less mold contamination and having excellent moldability, release properties, moisture resistance and solder stress resistance.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to a storage medium at room temperature, less mold contamination, moldability, mold release, flame retardancy,
An object of the present invention is to provide a semiconductor device having excellent solder stress resistance.

[0005]

Means for Solving the Problems The present invention provides [1] (A)
Glycidyl ether of 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl (a) and glycidyl ether of bis (3,5-dimethyl-4-hydroxyphenyl) methane (b) An epoxy resin, (B) a phenolic resin represented by the general formula (1),
(C) All inorganic substances, (D) Formula (2), general formula (3), or a compound (Q) having tetra-substituted phosphonium (P) and two or more phenolic hydroxyl groups in one molecule, and phenol in one molecule A compound (M) with a conjugate base of a compound (Q) having two or more phenolic hydroxyl groups, wherein the conjugate base is one compound from the compound (Q) having two or more phenolic hydroxyl groups in one molecule. One or more curing accelerators selected from curing accelerators comprising a phenoxide type compound excluding hydrogen, and (E) a urethane compound of oxidized microcrystalline wax and a urethane compound of polyethylene oxide wax as essential components; Weight ratio between (a) and (b) (a / b)
Is 1/3 to 3 and the total amount of inorganic substances is 87 to 94% by weight in the total epoxy resin composition. The urethane compound of the oxidized microcrystalline wax and the urethane compound of the polyethylene oxide wax are included in the total epoxy resin composition in an amount of 0. 05-
(2) (A) glycidyl ether of 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl, wherein the epoxy resin composition is 0.4% by weight. (A) and an epoxy resin which is a glycidyl etherified product of bis (3,5-dimethyl-4-hydroxyphenyl) methane (b), (B) a general formula (1)
A phenolic resin represented by the formula: (C) all inorganic substances, (D) formula (2), general formula (3), tetra-substituted phosphonium (P)
A compound (Q) having two or more phenolic hydroxyl groups in one molecule and a conjugate base (M) of a compound (Q) having two or more phenolic hydroxyl groups in one molecule, One or more curing accelerators selected from curing accelerators composed of a phenoxide-type compound in which one hydrogen is removed from the compound (Q) in which the conjugate base has two or more phenolic hydroxyl groups in one molecule, and (E) ) An urethane-oxidized microcrystalline wax and a polyethylene oxide wax are used as essential components. The weight ratio (a / b) of (a) and (b) is 1/3 to 3, and all inorganic substances are all epoxy resin. 87 to 94% by weight of the composition, the bromine-containing organic compound and the antimony compound each containing 1000 ppm or less of each flame retardant component, and urethane of oxidized microcrystalline wax. Product urethane product of oxidized polyethylene wax, 0.05 total epoxy resin composition
0.4% by weight of an epoxy resin composition for semiconductor encapsulation,

[0006]

Embedded image (N is an average value and a positive number from 1 to 10)

[0007]

Embedded image

[0008]

Embedded image (Wherein, X1, X2, X3, and X4 are monovalent organic acids or monovalent aliphatic groups having an aromatic ring or a heterocyclic ring, and they may be the same or different from each other. Y1, Y2, Y3, and Y4 are a monovalent organic acid or a monovalent aliphatic group having an aromatic ring or a heterocyclic ring, and at least one of them is a proton that can be released outside the molecule. Is a group obtained by releasing one proton, which may be the same or different from each other.) [3] Item [1] 1 or [2] A semiconductor device, wherein a semiconductor element is encapsulated using the epoxy resin composition for semiconductor encapsulation described above.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxy resin used in the present invention comprises:
Glycidyl ether of 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl (a) and glycidyl ether of bis (3,5-dimethyl-4-hydroxyphenyl) methane (b) Yes, it is a crystalline solid at room temperature, but has the property of becoming a very low viscosity liquid when melted by heating. This makes it possible to increase the amount of the inorganic filler, and thus reduce the moisture absorption of the cured product of the epoxy resin composition. Therefore, a semiconductor device sealed with a resin composition using these epoxy resins can have high reliability even under a soldering process at the time of mounting.

The epoxy resin used in the present invention is 4,4 ′
Glycidyl etherified product of -dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl (a) and bis (3,3)
The weight ratio (a / b) of 5-dimethyl-4-hydroxyphenyl) methane to the glycidyl etherified product (b) is preferably in the range of 1/3 to 3, more preferably 1/2.
~ 2. If the ratio is out of this range, characteristics such as excellent fluidity, curability, and resistance to solder stress cannot be sufficiently exhibited, which is not preferable. The method for mixing the resins is not particularly limited. 4,4'-dihydroxy-3,3 ', 5,5'
An epoxy resin comprising a glycidyl etherified product of tetramethylbiphenyl (a) and a glycidyl etherified product of bis (3,5-dimethyl-4-hydroxyphenyl) methane (b) as long as the epoxy resin does not impair the essential properties. You may use together with resin. When used in combination, it is desirable to use as low a viscosity as possible for all monomers, oligomers and polymers having an epoxy group in the molecule.
However, when a low-viscosity epoxy resin is used, the inorganic filler can be highly filled and the soldering stress resistance can be improved. However, since the crosslink density is low, moldability and mold release properties may be inferior. Therefore, the moldability and the mold release property can be improved by using the curing accelerator and the mold release agent of the present invention described later.

The phenolic resin represented by the general formula (1) used in the present invention has a methylene-biphenyl skeleton-methylene structure, and a cured product of an epoxy resin composition using the same has a low elastic modulus. Also, since it has low moisture absorption, it has excellent adhesion to metals such as lead frames and semiconductor elements such as silicon chips. n is an average value of 1 to 10 positive numbers, and the weight ratio of n = 1 to 3 is desirably 50% or more. When the weight ratio of n = 4 or more increases, the resin viscosity increases and the fluidity decreases. General formula (1)
By adjusting the amount of the phenol resin used, the solder stress resistance can be maximized. To bring out the effect of solder stress resistance,
It is desirable that the phenolic resin represented by the general formula (1) be contained in an amount of at least 30% by weight, preferably at least 50% by weight, based on the total amount of the phenolic resin. If the amount is less than 30% by weight, the solder stress resistance may be insufficient. The phenol resin represented by the general formula (1) used in the present invention may be used in combination with another phenol resin as long as the properties of the phenol resin are not impaired.
When used in combination, it is desirable to use a monomer, oligomer or polymer having a phenolic hydroxyl group in the molecule that has as low a viscosity as possible. However, when a phenol resin having low viscosity and flexibility is used, the crosslink density becomes low, so that the moldability and the releasability may be inferior. Therefore, by using the curing accelerator and the release agent of the present invention described later, the moldability and the release property can be improved. The equivalent ratio of the epoxy group of all epoxy resins used in the present invention to the phenolic hydroxyl group of all phenolic resins is preferably 0.5 to 2, and more preferably 0.7 to 1.5. 0.5-2
If the ratio is out of the range, the moisture resistance, the curability and the like are undesirably reduced.

The total inorganic substance used in the present invention is a sum of an inorganic filler generally used in a sealing material and an inorganic substance such as an antimony compound as a flame retardant and an inorganic ion exchanger added as needed. is there. The type of the inorganic filler used in the present invention is not particularly limited, and examples thereof include fused silica, fused spherical silica, crystalline silica, secondary aggregated silica, alumina, titanium white, and aluminum hydroxide. Is preferred. As the shape of the fused spherical silica, it is preferable that the shape is infinitely spherical and the particle size distribution is broad in order to improve fluidity. The content of all inorganic substances is preferably 87 to 94% by weight in the whole epoxy resin composition. If it is less than 87% by weight, low moisture absorption is not obtained and solder stress resistance becomes insufficient, and bromine-containing organic compounds such as brominated orthocresol novolak type epoxy resin and brominated bis A type epoxy resin and antimony trioxide, Unless a flame retardant such as an antimony compound such as antimony tetroxide is added, the flame retardancy is insufficient, which is not preferable. If it exceeds 94% by weight, the fluidity is reduced,
It is not preferable because there is a possibility that incomplete filling or the like may occur at the time of molding or a problem such as deformation of a gold wire in the semiconductor device due to an increase in viscosity may occur. In the present invention, the flame retardant of the bromine-containing organic compound and the antimony compound is 1000 ppm or less for each flame retardant component. Even if the flame retardant is not intentionally added, it is difficult to set the level mixed in the raw materials and the production stage to 0 ppm for economic reasons. And 0 ppb, the function of the present invention is effective. It is preferable that the inorganic filler used in the present invention is sufficiently mixed in advance. If necessary, the inorganic filler may be treated in advance with a coupling agent, an epoxy resin, or a phenol resin, and may be used.
There are a method of removing the solvent after mixing using a solvent, and a method of adding the solvent directly to the inorganic filler and treating the mixture using a mixer.

The curing accelerator represented by the formula (2) used in the present invention does not exhibit catalytic activity at normal temperature, so that the curing reaction of the epoxy resin composition does not proceed, and the catalytic activity is exhibited at high temperature during molding. Once exhibited, they exhibit a higher catalytic activity than conventional curing accelerators, and have the characteristic of highly curing epoxy resin compositions. The curing accelerator represented by the general formula (3) used in the present invention comprises phosphonium borate. However, in the general formula (3), X1, X2, X3 and X4 of the phosphonium group are a monovalent organic group or a monovalent aliphatic group having an aromatic ring or a heterocyclic ring, and they are the same as each other. May also be different. Such phosphonium groups include, for example, tetraphenylphosphonium, tetratolylphosphonium,
Tetraethylphenylphosphonium, tetramethoxyphenylphosphonium, tetranaphthylphosphonium, tetrabenzylphosphonium, ethyltriphenylphosphonium, n-butyltriphenylphosphonium, 2-hydroxyethyltriphenylphosphonium, trimethylphenylphosphonium, methyldiethylphenylphosphonium, methyldiallylphenylphosphonium And tetra-n-butylphosphonium. In the general formula (3), X1, X2, X3 and X4 are particularly preferably a monovalent organic group having an aromatic ring,
The melting point of the phosphonium borate represented by the general formula (3) is not particularly limited, but is preferably 250 ° C. or less from the viewpoint of uniform dispersion. In particular, phosphonium borate having a tetraphenylphosphonium group,
It has good compatibility with epoxy resins and phenolic resins, and can be suitably used.

In the general formula (3), Y of the borate group
1, Y2, Y3 and Y4 are a monovalent organic group or a monovalent aliphatic group having an aromatic ring or a heterocyclic ring, and at least one of them has at least a proton capable of being released outside the molecule. The proton donor having one proton is a group formed by releasing one proton, and Y1, Y2, Y3 and Y4
May be the same or different. Examples of such a proton donor that provides a borate group include aromatic acids such as benzoic acid, 1-naphthoic acid, 2-naphthoic acid, phthalic acid, trimellitic acid, pyromellitic acid, and 2,6-naphthalenedicarboxylic acid. Phenolic compounds such as carboxylic acid, phenol, biphenol, bisphenol A, bisphenol F, 1-naphthol, 2-naphthol, and polyphenol are good and can be suitably used. When the curing accelerator represented by the general formula (3) used in the present invention is mixed with the epoxy resin composition, it does not show catalytic activity at room temperature, so that the curing reaction of the epoxy resin does not progress, and the At high temperatures, catalytic activity develops,
Once developed, the epoxy resin composition exhibits a higher catalytic activity than conventional curing accelerators and cures the epoxy resin composition to a high degree.

The compound (Q) having two or more phenolic hydroxyl groups in one molecule and the tetra-substituted phosphonium (P) used in the present invention and two or more phenolic hydroxyl groups in one molecule.
A compound (M) with a conjugate base of a compound (Q) having at least two phenolic hydroxyl groups, wherein the compound is a phenoxide-type compound obtained by removing one hydrogen from the compound (Q) having at least two phenolic hydroxyl groups. The substituent of the tetra-substituted phosphonium (P), which is one of the constituents, is not limited, and the substituents may be the same or different. For example, a tetra-substituted phosphonium ion having a substituted or unsubstituted aryl group or alkyl group as a substituent is preferable because it is stable against heat and hydrolysis. Specifically, tetraphenylphosphonium, tetratolylphosphonium, tetraethylphenylphosphonium, tetramethoxyphenylphosphonium, tetranaphthylphosphonium, tetrabenzylphosphonium,
Examples include ethyltriphenylphosphonium, n-butyltriphenylphosphonium, 2-hydroxyethyltriphenylphosphonium, trimethylphenylphosphonium, methyldiethylphenylphosphonium, methyldiallylphenylphosphonium, tetra-n-butylphosphonium and the like.

The compound (Q) having two or more phenolic hydroxyl groups in one molecule, which is a component of the molecular aggregate (M) used in the present invention, includes, for example, bis (4-hydroxy-3,5-dimethyl) Phenyl) methane (commonly known as tetramethylbisphenol F), 4,4'-sulfonyldiphenol, 4,4'-isopropylidenediphenol (commonly known as bisphenol A), bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) )methane,
(2-hydroxyphenyl) (4-hydroxyphenyl) methane and their bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) methane,
Bisphenols such as three kinds of mixtures of (2-hydroxyphenyl) (4-hydroxyphenyl) methane (for example, bisphenol FD manufactured by Honshu Chemical Industry Co., Ltd.), 1,2-benzenediol, and 1,3 Dihydroxybenzenes such as -benzenediol and 1,4-benzenediol; trihydroxybenzenes such as 1,2,4-benzenetriol; various isomers of dihydroxynaphthalenes such as 1,6-dihydroxynaphthalene; '
-Phenol, compounds such as various isomers of biphenols such as 4,4'-biphenol, phenol novolak resins, phenol aralkyl resins and the like. Further, the conjugate base as another component is a phenoxide-type compound obtained by removing one hydrogen from the compound (Q).

The molecular-molecule aggregate (M) of the present invention has a phosphonium-phenoxide type salt in its structure as described above, but differs from the conventional phosphonium-organic acid anion salt type compound in that In the molecular aggregate (M) of the present invention, a higher-order structure due to hydrogen bonding surrounds ionic bonds. In the salt of the prior art, the reactivity is controlled only by the strength of the ionic bond. On the other hand, in the molecular aggregate (M) of the present invention, the enclosing by the higher order structure of the anion protects the active site at normal temperature. While doing
In the molding stage, the active sites are exposed by the collapse of the higher-order structure, and a so-called latency that expresses reactivity is imparted. The method for producing the molecular aggregate (M) of the present invention is not limited at all, but two typical methods can be mentioned. The first is to react a tetra-substituted phosphonium / tetra-substituted borate (Z) with a compound (Q) having two or more phenolic hydroxyl groups in one molecule at a high temperature, and then further to a boiling point of 60 ° C. or more. Is a method in which a thermal reaction is carried out in a solvent of The second is a method in which a compound (Q) having two or more phenolic hydroxyl groups in one molecule is reacted with an inorganic base or an organic base and a tetra-substituted phosphonium halide.

The substituent of the tetra-substituted phosphonium halide to be used is not limited at all, and the substituents may be the same or different. For example, a tetra-substituted phosphonium ion having a substituted or unsubstituted aryl group or alkyl group as a substituent is preferable because it is stable against heat and hydrolysis. Specifically, tetraphenylphosphonium, tetratolylphosphonium, tetraethylphenylphosphonium, tetramethoxyphenylphosphonium, tetranaphthylphosphonium, tetrabenzylphosphonium, ethyltriphenylphosphonium, n-
Examples thereof include butyltriphenylphosphonium, 2-hydroxyethyltriphenylphosphonium, trimethylphenylphosphonium, methyldiethylphenylphosphonium, methyldiallylphenylphosphonium, and tetra-n-butylphosphonium. Examples of the halide include chloride and bromide, which may be selected from the properties of the tetra-substituted phosphonium halide, such as the price and moisture absorption, and the availability, and any of them may be used. Also, as long as the properties of these curing accelerators are not impaired, triphenylphosphine, 1,8-diazabicyclo (5,4,
0) There is no problem when used in combination with other curing accelerators such as undecene-7 and 2-methylimidazole.

The urethane compound of the oxidized microcrystalline wax and the urethane compound of the oxidized polyethylene wax used in the present invention act as a release agent. The oxidized microcrystalline wax before urethanization is obtained by oxidizing a microcrystalline wax containing n-paraffin and a branched hydrocarbon obtained from a heavy oil fraction, and contains a carboxyl group and a hydroxyl group. Generally, oxidized microcrystalline wax is
While the viscosity of the epoxy resin composition can be reduced, the compatibility with the resin component is poor, and the epoxy resin composition excessively seeps into the mold surface during molding, and has excellent mold releasability, but has the disadvantage of severe mold contamination. Therefore, when a urethane compound of oxidized microcrystalline wax is used, it is possible to prevent mold staining due to appropriate compatibility with a resin component and achieve excellent mold release properties.

The oxidized polyethylene wax before urethanization is obtained by an ethylene polymerization method or by oxidizing polyethylene wax obtained as a thermal decomposition product of polyethylene, and contains a carboxyl group or a hydroxyl group. Those having a molecular weight of about 1,000 to 10,000 are generally used. Although the molecular weight is not particularly limited, it is preferable to use one having a low molecular weight in order to reduce the viscosity of the epoxy resin composition. In general, oxidized polyethylene wax has the disadvantage that the melting point is high, the compatibility with the resin component is poor, the mold surface excessively seeps out during molding, and the mold stain is severe. Therefore, when a urethane compound of oxidized polyethylene wax is used, it is possible to prevent mold contamination due to appropriate compatibility with the resin component.

According to the present invention, the use of a urethane compound of oxidized microcrystalline wax and a urethane compound of polyethylene oxide wax prevents the contamination of the mold, has excellent releasability, and furthermore, the semiconductor element inside the semiconductor device and the semiconductor element mounted thereon. The adhesiveness of the interface between the lead frame and the cured product of the epoxy resin composition is also improved, and the moisture resistance and solder crack resistance are dramatically improved. The method of urethanization is not particularly limited, but is performed by reacting isocyanates such as methylene diisocyanate and tolylene diisocyanate with hydroxyl groups and carboxyl groups of oxidized microcrystalline wax or oxidized polyethylene wax. In the present invention, a pre-urethane oxidized microcrystalline wax and a pre-urethane oxidized polyethylene wax may be used as a releasing agent, or a pre-mixed oxidized microcrystalline wax and polyethylene oxide may be used. The urethane compound may be used as the release agent. The proportion of urethanization is not particularly limited, but the content of nitrogen in the obtained wax is preferably about 0.3 to 5% by weight. If the urethane portion is too large, the adhesiveness is improved, but the viscosity of the wax itself increases, and it becomes difficult to materialize. If the urethane-forming portion is too small, sufficient adhesion cannot be obtained, and moisture resistance and solder crack resistance cannot be exhibited.

Other release agents can be used in combination as long as the properties of the urethanized wax of the present invention are not impaired. Examples of those which can be used in combination include natural waxes such as carnauba wax and metal salts of higher fatty acids such as zinc stearate. These may be used alone or in combination. The addition amount of the urethanized wax of the present invention is 0.05 to 0.4 in all epoxy resin compositions.
% By weight is preferred. If the amount is less than 0.05% by weight, sufficient releasability cannot be obtained, and if the amount exceeds 0.4% by weight, although mold releasability is sufficient, mold fogging is not preferred.

The epoxy resin composition of the present invention comprises (A)
In addition to the component (E), if necessary, an inorganic ion exchanger such as bismuth oxide hydrate, a coupling agent such as γ-glycidoxypropyltrimethoxysilane, a coloring agent such as carbon black and red iron, silicone oil, Various additives such as a low-stress component such as silicone rubber and an antioxidant may be appropriately compounded. The epoxy resin composition of the present invention is obtained by mixing the components (A) to (E) and other additives at room temperature using a mixer, kneading the mixture with a kneading machine such as a roll, a kneader, an extruder, and cooling. Obtained by grinding. In order to manufacture a semiconductor device by encapsulating an electronic component such as a semiconductor element using the epoxy resin composition of the present invention, it is sufficient to cure and mold by a molding method such as a transfer mold, a compression mold, and an injection mold.

[Synthesis of Molecular Association (M)] Synthesis Example 1 Bisphenol FD 300 manufactured by Honshu Chemical Industry Co., Ltd.
g (1.5 mol) and 329 g (0.5 mol) of tetraphenylphosphonium / tetraphenylborate (Z) were charged into a 3 L separable flask and reacted at 200 ° C. for 3 hours. The amount of benzene distilled in this reaction was 97% by weight of the theoretical amount (that is, the benzene distillation rate was 97%). The crude product of this reaction is pulverized, charged into a separable flask, 2-propanol is added in an amount three times the charged weight of the crude product, and the internal temperature is increased to 82.4 ° C. (boiling point temperature of 2-propanol). Stir for 5 hours. Thereafter, most of the 2-propanol was removed, and a low-boiling component was further removed under heating and reduced pressure. The obtained product was designated as compound (M-1). The solvent was deuterated methanol, and the ¹ H-
NMR measurements were made. Around 4.8 ppm and 3.3
The peak around ppm is the peak of the solvent, 6.4 to 7.1.
The peak group around ppm is bisphenol F as a raw material.
[(P) 1 mole per mole (a)] and a phenoxide type conjugate base obtained by removing one hydrogen from this bisphenol F [mole number (b) per 1 mole (P)] phenyl proton, 7.6 The peak group around -8.0 ppm
It is assigned to the phenyl proton of the tetraphenylphosphonium group, and the molar ratio is [(a + b) /
(P)] = 2.2 / 1.

Synthesis Example 2 In a 5 L separable flask, 300 g (1.5 mol) of bisphenol FD manufactured by Honshu Chemical Industry Co., Ltd., and 314 g (0.75 mol) of tetraphenylphosphonium bromide manufactured by Hokuko Chemical Industry Co., Ltd. ) And 3000 g of methanol were charged and completely dissolved. A methanol / water mixed solution containing 30 g of sodium hydroxide was added dropwise thereto with stirring. A reprecipitation operation of dropping the obtained solution into a large amount of water was performed to obtain the target substance as a solid. The solid obtained by filtration was taken out and dried to obtain a product, which was obtained as compound (M-
2). The solvent is heavy methanol, and (M-2)
Was measured by ¹ H-NMR. The peaks around 4.8 ppm and 3.3 ppm are the peaks of the solvent, 6.4 ppm.
A group of peaks in the vicinity of to 7.1 ppm is the starting material bisphenol F [moles (a) per mol of (P)] and a phenoxide-type conjugate base [(P) 1 Number of moles per mole (b)]
The peak group around 7.6 to 8.0 ppm is assigned to the phenyl proton of the tetraphenylphosphonium group, and the molar ratio is [(a
+ B) / (P)] = 2/1.

[0026]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. The mixing ratio is by weight. Example 1 The following composition: an epoxy resin containing a glycidyl etherified product of 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylbiphenyl as a main component (YX4000H, melting point: 105 ° C, epoxy equivalent: 197 g) Epoxy resin (hereinafter referred to as E-1) 2.03 parts by weight Epoxy resin containing glycidyl ether of bis (3,5-dimethyl-4-hydroxyphenyl) methane as a main component (epoxy equivalent: 192 g / eq. (Hereinafter referred to as epoxy resin (E-2)) 2.03 parts by weight Phenolic resin represented by formula (4) (hydroxyl equivalent: 203 g / eq) 4.24 parts by weight Fused spherical silica 90.00 parts by weight Formula (2) Curing accelerator shown 0.30 parts by weight Wax 1 [Tolylene diisocyanate of oxidized microcrystalline wax and polyethylene oxide wax -Melting point 89 ° C., acid value 16, saponification value 60] 0.30 part by weight Inorganic ion exchanger 0.50 part by weight γ-glycidoxypropyltrimethoxysilane 0.30 part by weight Carbon black 0.30 part by weight Of the mixture at room temperature using a mixer.
The mixture was kneaded using an axial roll, cooled and pulverized to obtain a resin composition. The obtained resin composition was evaluated by the following method. Table 1 shows the results.

Embedded image

Evaluation method Spiral flow: Measurement was performed using a mold for spiral flow measurement in accordance with EMMI-1-66 at a mold temperature of 175 ° C., an injection pressure of 70 kg / cm ² , and a curing time of 2 minutes. The unit is cm. Curing Torque: Using a curast meter (manufactured by Orientec Co., Ltd., JSR curast meter IVPS type), a torque at a mold temperature of 175 ° C. and 90 seconds after the start of heating was determined.
The torque in the curast meter is a parameter of curability, and the larger the numerical value, the better the curability. The unit is kgf · cm. Storage at 25 ° C .: After storing the resin composition at 25 ° C. for 3 days, the spiral flow was measured and expressed as a percentage of the spiral flow immediately after the adjustment of the resin composition. Flame retardancy: tableting the resin composition, using a low pressure transfer molding machine, mold temperature 175 ° C, injection pressure 75
kg / cm ² , curing time 2 minutes, length 127 mm, width 1
A molded product having a thickness of 2.7 mm and a thickness of 1.6 mm is formed and UL-
A flame retardancy test was performed according to 94. Releasability: Using a transfer molding machine, mold temperature 18
0 ° C., injection pressure 75 kg / cm ² , curing time 1 min.
4pLQFP (20 × 20 × 1.4mm thickness) 300
Molded continuously. X indicates that the product adhered to the mold at the time of mold release or cracked or chipped, and ○ indicates that it did not.
It was determined. Mold contamination: mold temperature 1 using a transfer molding machine
80 ° C, injection pressure 75 kg / cm ² , curing time 1 min.
44pLQFP (20 × 20 × 1.4mm thickness) with 30
Molding was performed 0 times continuously. A sample having whitening on both the surface of the molded product and the mold surface was evaluated as x, a sample having whitening on either one was evaluated as Δ, and a sample having neither whitening was evaluated as ○. Moisture resistance: tableting the resin composition, using a low pressure transfer molding machine, mold temperature 180 ° C, injection pressure 10
0 kg / cm ² , curing time 1 minute, 144pLQFP (2
(0 × 20 × 1.4 mm thickness). Eight packages treated at 175 ° C for 8 hours as post cure,
After processing for 168 hours in an environment of 85 ° C. and a relative humidity of 60%, IR reflow processing (260 ° C.) was performed. The presence or absence of peeling inside after the treatment was observed with an ultrasonic flaw detector, and those with peeling from the internal element were judged as x, and those without peeling were judged as o. Solder stress resistance: The resin composition is made into tablets, and using a low-pressure transfer molding machine, a mold temperature of 180 ° C., an injection pressure of 100 kg / cm ² , and a curing time of 1 minute are set to 144.
pLQFP (20 × 20 × 1.4 mm thickness) was molded. Eight packages treated at 175 ° C. for 8 hours as post-curing were placed in an environment at 85 ° C. and a relative humidity of 60% for 1 hour.
After the treatment for 68 hours, an IR reflow treatment (260 ° C.) was performed. The presence or absence of internal cracks after the treatment was observed with an ultrasonic flaw detector, and the number of defective packages was counted. When the number of defective packages is n, it is displayed as n / 8. Table 1 shows the evaluation results.

Examples 2 to 6, Comparative Examples 1 to 7 Resin compositions were obtained in the same manner as in Example 1 according to the formulations in Tables 1 and 2, and evaluated in the same manner as in Example 1. The results are shown in Tables 1 and 2. In Examples 2 and 6, and Comparative Examples 2 and 6, the curing accelerator of the formula (5) was used. DB of Comparative Examples 3 and 7
U is 1,8-diazabicyclo (5,4,0) undecene-7. In Comparative Examples 5 and 6, a phenol aralkyl resin (manufactured by Mitsui Chemicals, Inc., XL-225, softening point 75)
° C and a hydroxyl equivalent of 174 g / eq). Example 2,
Wax 2 used in Comparative Examples 1 and 5 was tolylene diisocyanate of oxidized microcrystalline wax and polyethylene oxide, and had a melting point of 82 ° C., an acid value of 18, and a saponification value of 50. The oxidized microcrystalline wax used in Comparative Examples 4 and 6 has a melting point of 90 ° C. The oxidized polyethylene wax used in Comparative Examples 4 and 7 had a melting point of 92.
° C.

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[0029]

[Table 1]

[0030]

[Table 2]

[0031]

According to the present invention, it is possible to stably store at room temperature for a long period of time without curing, and when heated during molding, a rapid curing reaction develops, resulting in good moldability. Thus, an epoxy resin composition showing releasability is obtained, and a semiconductor device using the same is excellent in flame retardancy and solder stress resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 75/04 C08L 75/04 H01L 23/29 H01L 23/30 R 23/31

Claims (3)

[Claims] (A) 4,4'-dihydroxy-3,
Glycidyl etherified product of 3 ', 5,5'-tetramethylbiphenyl (a) and bis (3,5-dimethyl-4-
An epoxy resin which is a glycidyl etherified product of (hydroxyphenyl) methane (b), (B) a phenolic resin represented by the general formula (1), (C) all inorganic substances, (D) a formula (2), a general formula (3), Alternatively, a compound (Q) having two or more phenolic hydroxyl groups in one molecule with a tetra-substituted phosphonium (P) and a compound having two or more phenolic hydroxyl groups in one molecule.
A molecular conjugate (M) of a compound (Q) having at least two phenolic hydroxyl groups in one molecule of the compound (Q) having at least two phenolic hydroxyl groups in the molecule. One or more curing accelerators selected from curing accelerators comprising a phenoxide-type compound, and (E) a urethane compound of oxidized microcrystalline wax and a urethane compound of polyethylene oxide wax as essential components;
And the weight ratio (a / b) of (b) to (b) is 1/3 to 3, the total amount of the inorganic substance is 87 to 94% by weight in the total epoxy resin composition, and the urethane compound of the oxidized microcrystalline wax and the polyethylene oxide wax The epoxy resin composition for semiconductor encapsulation, wherein the urethane compound is 0.05 to 0.4% by weight of the total epoxy resin composition. (A) 4,4′-dihydroxy-3,
Glycidyl etherified product of 3 ', 5,5'-tetramethylbiphenyl (a) and bis (3,5-dimethyl-4-
An epoxy resin which is a glycidyl etherified product of (hydroxyphenyl) methane (b), (B) a phenolic resin represented by the general formula (1), (C) all inorganic substances, (D) a formula (2), a general formula (3), Tetra-substituted phosphonium (P)
A compound (Q) having two or more phenolic hydroxyl groups in one molecule and a conjugate base (M) of a compound (Q) having two or more phenolic hydroxyl groups in one molecule, One or more curing accelerators selected from curing accelerators composed of a phenoxide-type compound in which one hydrogen is removed from the compound (Q) in which the conjugate base has two or more phenolic hydroxyl groups in one molecule, and (E) ) An urethane-oxidized microcrystalline wax and a polyethylene oxide wax are used as essential components. The weight ratio (a / b) of (a) and (b) is 1/3 to 3, and all inorganic substances are all epoxy resin. 87 to 94% by weight of the composition, the bromine-containing organic compound and the antimony compound each containing 1000 ppm or less of each flame retardant component, and urethane of oxidized microcrystalline wax. Product urethane product of oxidized polyethylene wax, 0.05 total epoxy resin composition
An epoxy resin composition for semiconductor encapsulation, which is 0.4% by weight. Embedded image (N is an average value and a positive number of 1 to 10) Embedded image (Wherein, X1, X2, X3, and X4 are monovalent organic acids or monovalent aliphatic groups having an aromatic ring or a heterocyclic ring, and they may be the same or different from each other. Y1, Y2, Y3, and Y4 are a monovalent organic acid or a monovalent aliphatic group having an aromatic ring or a heterocyclic ring, and at least one of them is a proton that can be released outside the molecule. Is a group obtained by releasing one proton, which may be the same or different from each other.) 3. A semiconductor device comprising a semiconductor element encapsulated with the epoxy resin composition for semiconductor encapsulation according to claim 1 or 2.