JP2001261782A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin composition which is useful for sealing semiconductors and has excellent moldability, fast curability, flowability, flame retardancy, high temperature storage characteristics, moisture resistance reliability and solder crack resistance. SOLUTION: This epoxy resin composition for sealing semiconductors, characterized y containing an epoxy resin, a phenolic resin, a tetrasubstituted phosphonium compound, an inorganic filler, a metal hydroxide solid solution represented by general formula (1): Mg1-xM2+x(OH)2 [M2+ is at least one divalent metal ion selected from the group consisting of Mn2+, Fe2+, Co2+, Mi2+, Cu2+ and Zn2+; (x) exhibits the number of 0.01<=(x)<=0.5], and zinc borate represented by general formula (2): pZnO.qB2O3.rH2O (2) [(p), (q) and (r) are each the positive number] as essential components.

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 which does not contain a halogen-based flame retardant and an antimony compound and has excellent flame retardancy and high-temperature storage characteristics, and a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, electronic components such as diodes, transistors, and integrated circuits are mainly sealed with an epoxy resin composition. These epoxy resin compositions contain a halogen-based flame retardant and an antimony compound in order to impart flame retardancy. However, development of an epoxy resin composition having excellent flame retardancy without using a halogen-based flame retardant and an antimony compound is demanded from the viewpoint of environment and hygiene. Further, when a semiconductor device sealed with an epoxy resin composition containing a halogen-based flame retardant and an antimony compound is stored at a high temperature, a thermally decomposed halide is liberated from these flame retardant components and the semiconductor element is bonded. Is known to corrode the semiconductor device and impair the reliability of the semiconductor device.
There is a demand for an epoxy resin composition that can achieve a flame retardant grade of V-0 of UL-94 without using a halogen-based flame retardant and an antimony compound as the flame retardant. As described above, the junction portion (bonding pad portion) of the semiconductor element after storing the semiconductor device at a high temperature (for example, 185 ° C.).
The high-temperature storage characteristics are referred to as the high-temperature storage characteristics. Examples of a method for improving the high-temperature storage characteristics include a method using diantimony pentoxide (Japanese Patent Laid-Open No. 55-146950) and a method using antimony oxide and organic phosphine. (Japanese Patent Application Laid-Open No. 61-53321) and the like have been proposed and their effects have been confirmed. However, with respect to the recent high level of high-temperature storage characteristics required for semiconductor devices, depending on the type of epoxy resin composition, Some are unsatisfactory. In addition, zinc borate has been proposed as a flame retardant, and by adding a large amount thereof, a flame retardant grade V-0 can be achieved, and there is no problem in high-temperature storage characteristics. There is a problem that solder crack resistance is reduced. As a technique for improving the above-mentioned drawbacks, flame retardancy is achieved by using a combination of a specific metal hydroxide and a specific metal oxide, or using a composite metal hydroxide of a specific metal hydroxide and a specific metal oxide. Proposals have been made to solve the problems of the reliability and the humidity resistance (JP-A-10-251486, JP-A-11-11-11).
No. 945), in order to exhibit sufficient flame retardancy, a large amount of addition is required, and therefore, there is a problem that the moldability and the solder crack resistance are lowered. Also, in recent years, multi-molding has increased from the point of moldability, and the molding cycle has been shortened. In the case of using zinc borate, a problem that curability is reduced and the molding cycle cannot be shortened has begun to occur. . As a means of improving curability,
An increase in the amount of the curing accelerator may be mentioned, but problems such as poor filling and wire breakage occur due to a decrease in fluidity (increase in viscosity). That is, an epoxy resin composition which maintains flame retardancy, is excellent in moldability, rapid curing properties, high-temperature storage properties, moisture resistance reliability and solder crack resistance, does not use a halogen-based flame retardant, and does not use an antimony compound is required. I have.

[0003]

The present invention does not contain a halogen-based flame retardant and an antimony compound, and has excellent moldability, rapid curing properties, flame retardancy, high-temperature storage characteristics, moisture resistance reliability and solder crack resistance. An epoxy resin composition for semiconductor encapsulation, and a semiconductor device obtained by encapsulating a semiconductor element using the same.

[0004]

Means for Solving the Problems The present inventor has proposed a halogen-based compound.
Moldability, fast curing without flame retardant and antimony compound
, Flame-retardant, high-temperature storage characteristics, moisture-resistant reliability and solder-resistant
As a result of intensive studies to improve
Epoxy resin using curing agent and specific compound as curing accelerator
Fat compositions have been found to exhibit very good properties.
The present invention has been completed on the basis of the findings described above. The present invention
Are (A) epoxy resin, (B) phenolic resin,
(C) tetra-substituted phosphonium compound, (D) inorganic filling
Material, (E) solid solution of metal hydroxide represented by general formula (1)
And (F) zinc borate represented by the general formula (2).
Sub ingredient, Mg_1-xM²⁺ _x(OH)_Two (1) (where M²⁺Is Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu
²⁺And Zn²⁺At least one member selected from the group consisting of
X is a number satisfying 0.01 ≦ x ≦ 0.5
PZNO · qB_TwoO_Three・ RH_TwoO (2) (where p, q, and r are positive numbers) More preferably, the tetra-substituted phosphonium compound is
Compound represented by general formula (3), represented by general formula (4)
Compound, (G) Tetra-substituted phosphonium (X) and one molecule
Having two or more phenolic hydroxyl groups therein (Y)
Having two or more phenolic hydroxyl groups in one molecule
A molecular association of the compound (Y) with a conjugate base,
The base has two or more phenolic hydroxyl groups in one molecule.
Phenoxide obtained by removing one hydrogen from a compound (Y),
One or more selected from the group consisting of:
In the formula, M of the metal hydroxide solid solution represented by the general formula (1)²⁺
Is Zn ²⁺Or Ni²⁺And zinc borate is 2ZnO · 3B_Two
O_Three・ 3.5H_TwoO for semiconductor sealing characterized by being O
Epoxy resin composition and encapsulating semiconductor device using the same
A semiconductor device characterized by being stopped.

Embedded image (Wherein R _{1 to} R ₄ are the same or different groups selected from an alkyl group having 1 to 8 carbon atoms, a phenyl group or a substituted phenyl group)

[0005]

Embedded image (Here, R ₅ is an alkyl group, a phenyl group, or a naphthyl group.)

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin used in the present invention refers to all monomers, oligomers and polymers having two or more epoxy groups in one molecule, and their molecular weight and molecular structure are not particularly limited. For example, biphenyl type epoxy resin, bisphenol type epoxy resin,
Stilbene epoxy resin, naphthol epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin, triphenolmethane epoxy resin, alkyl-modified triphenolmethane epoxy resin, epoxy resin containing triazine nucleus, dicyclopentadiene-modified phenol resin An epoxy resin, a phenol aralkyl type epoxy resin (having a phenylene skeleton, a diphenylene skeleton and the like) and the like can be used, and these may be used alone or in combination.

The phenolic resin used in the present invention includes:
Monomers, oligomers and polymers generally having two or more phenolic hydroxyl groups in one molecule are not particularly limited in molecular weight and molecular structure. For example, phenol novolak resin, cresol novolak resin, dicyclopentadiene-modified phenol Resins, terpene-modified phenolic resins, triphenolmethane-type resins, phenol aralkyl resins (having a phenylene skeleton, diphenylene skeleton, and the like), naphthol aralkyl resins, and the like, may be used alone or in combination.
Of these, phenol novolak resins, dicyclopentadiene-modified phenol resins, phenol aralkyl resins, terpene-modified phenol resins, and the like are particularly preferable. The ratio of the number of epoxy groups in all epoxy resins to the number of phenolic hydroxyl groups in all phenolic resins is preferably 0.8 to 1.3.

[0008] The curing accelerator used in the present invention is a tetra-substituted phosphonium compound and has a latent property. Since this curing accelerator does not show catalytic activity in a relatively low temperature range, the curing reaction of the epoxy resin composition does not proceed. That is, when the components are heated and kneaded, a part of the crosslinking reaction does not proceed promptly, so that a predetermined fluidity is maintained, and for the same reason, the epoxy resin composition also has excellent room temperature storage characteristics. In addition, in the high temperature range during molding, the epoxy resin composition exhibits higher catalytic activity than conventional curing accelerators, and highly cures the epoxy resin composition. The tetra-substituted phosphonium compound of the present invention includes a tetraphenylphosphonium-tetra-substituted borate represented by the general formula (3), a compound represented by the general formula (4), and (G) a tetra-substituted phosphonium (X) in one molecule. A molecular assembly of the compound (Y) having two or more phenolic hydroxyl groups and the compound (Y) having two or more phenolic hydroxyl groups in one molecule with a conjugate base,
The conjugate base is preferably at least one selected from the group consisting of phenoxide-type compounds obtained by removing one hydrogen from the compound (Y) having two or more phenolic hydroxyl groups in one molecule.

Examples of the tetraphenylphosphonium / tetrasubstituted borate compound represented by the general formula (3) include, for example, tetraphenylphosphonium / tetraphenylborate, tetraphenylphosphonium / ethyltriphenylborate, tetraphenylphosphonium / tetraethylborate, tetraphenyl Examples thereof include phosphonium tetrabutyl borate, and among these, tetraphenyl phosphonium tetraphenyl borate and tetraphenyl phosphonium tetrabutyl borate are preferable. As the compound represented by the general formula (4), a compound in which R ₅ is an alkyl group, a phenyl group, or a naphthyl group is preferable, and a compound in which R ₅ is a naphthyl group is particularly preferable.

The molecular aggregate of the present invention comprises a tetrasubstituted phosphonium (X) and a compound (Y) having two or more phenolic hydroxyl groups in one molecule and a compound (Y) having two or more phenolic hydroxyl groups in one molecule. ), Which is a phenoxide-type compound obtained by removing one hydrogen from the compound (Y) having two or more phenolic hydroxyl groups in one molecule. The substituent of the tetra-substituted phosphonium (X), which is one of the components of the molecular assembly of the present invention, 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 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.

[0011] The constituent component of the molecular aggregate of the present invention, 1
As the compound (Y) having two or more phenolic hydroxyl groups in the molecule, for example, bis (4-hydroxy-3,
5-dimethylphenyl) methane (commonly known as tetramethylbisphenol F), 4,4′-sulfonyldiphenol,
4,4′-isopropylidene diphenol (commonly known as bisphenol A), bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) methane, (2-hydroxyphenyl)-(4-hydroxyphenyl) methane, and these Inner bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) methane, and a mixture of three kinds of (2-hydroxyphenyl)-(4-hydroxyphenyl) methane (for example, manufactured by Honshu Chemical Industry Co., Ltd.
Bisphenols such as bisphenol FD);
-Benzenediol, 1,3-benzenediol, 1,
Dihydroxybenzenes such as 4-benzenediol,
Trihydroxybenzenes such as 1,2,4-benzenetriol; various isomers of dihydroxynaphthalenes such as 1,6-dihydroxynaphthalene; various kinds of biphenols such as 2,2′-biphenol and 4,4′-biphenol Examples include compounds such as isomers. Further, the conjugate base as another component is a phenoxide-type compound obtained by removing one hydrogen from the compound (Y).

Although the molecular aggregate of the present invention has a phosphonium-phenoxide type salt in its structure as described above, the difference from the conventional phosphonium-organic acid anion salt type compound is that In the aggregate, the higher-order structure due to the hydrogen bond surrounds the ionic bond. In the salt of the prior art, the reactivity is controlled only by the strength of the ionic bond, whereas in the molecular aggregate of the present invention, the enclosing by the higher-order structure of the anion protects the active site at normal temperature, while In the molding stage, the active sites are exposed due to the collapse of the higher-order structure, and so-called latency, which expresses reactivity, is imparted.

The method for producing the molecular aggregate of the present invention includes:
Although not limited at all, two typical methods can be mentioned. The first is a tetra-substituted phosphonium / tetra-substituted borate (Z) and two phenolic hydroxyl groups in one molecule.
This is a method in which a compound (Y) having at least one compound is reacted at a high temperature and then thermally reacted in a solvent having a boiling point of 60 ° C. or more. The second is a compound (Y) having two or more phenolic hydroxyl groups in one molecule, an inorganic base or an organic base,
This is a method of reacting with 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 from each other. For example, a tetra-substituted phosphonium ion having a substituted or unsubstituted aryl 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-butyltriphenylphosphonium, 2-hydroxyethyltriphenylphosphonium, Examples include trimethylphenylphosphonium, methyldiethylphenylphosphonium, methyldiallylphenylphosphonium, tetra-n-butylphosphonium and the like. Examples of the halide include chloride and bromide. The halide may be selected from the properties of the tetra-substituted phosphonium halide, such as the price and moisture absorption, and the availability thereof, and any of them may be used.

Further, other curing accelerators may be used together as long as the properties of the tetra-substituted phosphonium compound of the present invention are not impaired. For example, 1,8-
Examples thereof include diazabicyclo (5,4,0) undecene-7, triphenylphosphine, 2-methylimidazole and the like, and these may be used alone or as a mixture.
The amount of the curing accelerator of the present invention is 1.0 parts by weight per 100 parts by weight of the total amount of all epoxy resins and all phenolic resins.
-2.5 parts by weight is preferred, and it can be usually mixed at 70-150 ° C. If the amount is less than 1.0 part by weight, sufficient curability may not be obtained at the time of heat molding. On the other hand, if it exceeds 2.5 parts by weight, the curing is too fast and the flowability during molding decreases. It is not preferable because there is a possibility that poor filling may occur.

As the inorganic filler used in the present invention, those generally used for a sealing material can be used. For example, fused silica, crystalline silica, talc, alumina, silicon nitride and the like can be mentioned, and these may be used alone or in combination. As the compounding amount of the inorganic filler,
The total amount of the metal hydroxide solid solution, zinc borate, and the inorganic filler is preferably 60 to 95% by weight in the total epoxy resin composition in view of the balance between moldability and solder crack resistance. If it is less than 60% by weight, the solder cracking resistance decreases with an increase in water absorption, and if it exceeds 95% by weight, problems such as wire sweep and pad shift are caused, which is not preferable.

The metal hydroxide solid solution represented by the general formula (1) used in the present invention acts as a flame retardant. Its flame retarding mechanism is that the metal hydroxide solid solution starts dehydration and absorbs heat during combustion. It is considered that the combustion reaction is thereby inhibited, and the carbonization of the cured resin component is promoted to form a flame-retardant layer that blocks oxygen on the surface of the cured product. Further, the metal hydroxide solid solution of the present invention has an effect of appropriately lowering the endothermic onset temperature and improving the flame retardancy. If the endothermic start temperature is low, the moldability and reliability are adversely affected, and if the endothermic start temperature is higher than the decomposition temperature of the resin component, the flame retardancy decreases, but the endothermic start temperature of the metal hydroxide solid solution of the present invention is reduced. Is 300-35
It is a moderate value around 0 ° C. Of these, particularly preferred M ²⁺ are Ni ²⁺ and Zn ²⁺ . The amount of the metal hydroxide solid solution of the present invention is preferably 1 to 15% by weight, more preferably 1 to 1% by weight, based on the total epoxy resin composition.
0% by weight. If it is less than 1% by weight, the flame retardancy is insufficient and
If the content exceeds 5% by weight, the solder crack resistance and the moldability are undesirably reduced. The average particle size of the metal hydroxide solid solution of the present invention is preferably 0.5 to 30 μm, and more preferably 0.5 to 10 μm.

The zinc borate represented by the general formula (2) used in the present invention acts as a flame retardant similarly to the metal hydroxide solid solution. Zinc borate represented by the general formula (2) is 2ZnO.3B ₂ O ₃ from the viewpoint of a balance between flame retardancy and moisture resistance reliability.
· 3.5 H ₂ O and _{4ZnO · B 2 O 3 · H} 2 O and the like, in _{particular, 2ZnO · 3B 2 O 3 ·} 3.5H 2 O exhibits a high flame retardancy. The amount of zinc borate is preferably from 1 to 20% by weight, more preferably from 1 to 10% by weight, based on the whole epoxy resin composition. If it is less than 1% by weight, the flame retardancy is insufficient, and if it exceeds 20% by weight, the moisture resistance reliability and the moldability are undesirably reduced. 1 to 30μ as average particle size
m is preferable, and more preferably, 5 to 20 μm.

Each of the metal hydroxide solid solution and zinc borate has a property of imparting flame retardancy even when used alone, but a large amount of compounding is required to express sufficient flame retardancy. However, if it is blended in a large amount, the moldability and strength tend to decrease, and the water absorption tends to increase, and the solder crack resistance decreases. In order to prevent these physical properties from deteriorating, it is necessary to reduce the compounding amount as much as possible. The present inventor has found that by using a metal hydroxide solid solution and zinc borate in combination, the flame retardancy is further improved as a synergistic effect, and the blending amount can be reduced. Each of the flame retardants has an endothermic effect at the time of combustion, the metal hydroxide solid solution promotes the carbonization of the cured resin component, and the zinc borate enhances the strength of the carbonized layer by forming a glassy film. Although the reason is not clear, the combined use of both makes it possible to complement each other's abilities and obtain high flame retardancy as a synergistic effect. As a result, flame retardancy can be maintained even if the blending amount is reduced, and a decrease in moldability and strength, an increase in water absorption, and the like can be prevented.

The epoxy resin composition of the present invention comprises (A)
The component (F) is an essential component, but if necessary, a silane coupling agent, a coloring agent such as carbon black, a release agent such as natural wax and synthetic wax, and a low stress such as silicone oil and rubber. Various additives such as additives may be appropriately compounded. In addition, the epoxy resin composition of the present invention is prepared by mixing the components (A) to (F) and other additives sufficiently and uniformly using a mixer or the like, and then melt-kneading with a hot roll or a kneader. , After cooling and pulverized. Various electronic components such as semiconductor elements are encapsulated using the epoxy resin composition of the present invention, and semiconductor devices are manufactured by curing and molding using conventional molding methods such as transfer molding, compression molding, and injection molding. do it.

[0020]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited to these examples. First, the abbreviations and structures of the epoxy resins and phenol resins used in the examples and comparative examples are shown below. Epoxy resin (E-1): an epoxy resin represented by the formula (E-1) (epoxy equivalent: 265 g / eq)

Embedded image

Epoxy resin (E-2): an epoxy resin having a structure represented by the formula (E-2) as a main component (epoxy equivalent: 190 g / eq)

Embedded image

Phenol resin (H-1): Formula (H-1)
Phenolic resin (hydroxyl equivalent 104g / e)
q)

Embedded image

Phenol resin (H-2): Formula (H-2)
Phenolic resin (hydroxyl equivalent 165 g / e)
q)

Embedded image

[Synthesis Example of Molecular Aggregate] (Synthesis Example 1) Bisphenol F manufactured by Honshu Chemical Industry Co., Ltd.
-D [trade name of an isomer mixture of bis (monohydroxyphenyl) methane. Corresponds to compound (Y). ] 300g
(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 G1. Further, G1 was measured by ¹ H-NMR using heavy solvent as a solvent. The peaks around 4.8 ppm and 3.3 ppm are the peaks of the solvent, and the peak group around 6.4 to 7.1 ppm is the starting material bisphenol F [the number of moles (a) relative to 1 mole of (X) (X)] From bisphenol F 1
Phenoxide-type conjugated base [(X) 1
6. phenyl protons in moles per mole (b)];
The peak group around 6 to 8.0 ppm is attributed to the phenyl proton of the tetraphenylphosphonium group, and from their area ratio, the molar ratio is (a + b) / (X) = 2.2 / 1.
It was calculated to be

(Synthesis Example 2) 300 g (1.5 mol) of bisphenol FD (corresponding to compound (Y)) manufactured by Honshu Chemical Industry Co., Ltd. was placed in a 5-liter separable flask. 314 g (0.75 mol) of tetraphenylphosphonium bromide and 3000 g of methanol were charged and completely dissolved. Sodium hydroxide 3
A methanol / water mixed solution containing 0 g was added dropwise 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 was removed by filtration, and the product obtained by drying was designated as compound G2. The solvent as a heavy methanol, ¹ G2 H-NM
Measurements at R were made. Around 4.8 ppm and 3.3 pp
The peak near m is the peak of the solvent, which is 6.4 to 7.1 pp.
The peak group near m is bisphenol F as a raw material.
[(X) 1 mole per mole (a)] and a phenoxide-type conjugate base obtained by removing one hydrogen from this bisphenol F [(X) mole number (b) per 1 mole] 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) /
It was calculated that (X) = 2/1.

[Production Example of Epoxy Resin Composition] The compounding ratio is by weight. (Example 1) Epoxy resin (E-1) 13.3 parts by weight Phenol resin (H-1) 5.2 parts by weight Tetraphenylphosphonium / tetraphenylborate (hereinafter referred to as TPPK) 0.25 parts by weight Melted sphere Silica 67.95 parts by weight Metal hydroxide solid solution (Mg _0.8 Zn _0.2 (OH) ₂ , average particle size 1 μm) 6.0 parts by weight Zinc borate (2ZnO.3B ₂ O ₃ .3.5H ₂ O, average particle size 6.0 parts by weight Epoxy silane coupling agent 0.5 parts by weight Carbon black 0.3 parts by weight Carnauba wax 0.5 parts by weight was mixed at room temperature using a super mixer, and 70 to 10 parts by weight were mixed.
Roll kneading was performed at 0 ° C., followed by cooling and pulverization to obtain an epoxy resin composition. The obtained epoxy resin composition was evaluated by the following method. Table 1 shows the results.

Evaluation method Spiral flow: Measured using a mold for measuring spiral flow according to EMMI-1-66, at a mold temperature of 175 ° C., a pressure of 70 kg / cm ² and a curing time of 120 seconds. Shore D hardness: mold temperature 180 ° C, injection pressure 100kg
/ Cm ² and a curing time of 50 seconds, and the value of Shore D hardness measured 10 seconds after opening the mold is defined as curability. Shore D hardness is an index of curability, and the larger the numerical value, the better the curability. Flame retardancy: A test piece (127 mm × 12.7 mm × 3.2 mm) was molded using a low pressure transfer molding machine at a molding temperature of 175 ° C., a pressure of 70 kg / cm ² , and a curing time of 120 seconds. After treating for 8 hours, the flame retardancy was determined according to the UL-94 vertical method. Hot strength: A test piece (80 mm × 10 mm × 4 mm) was molded using a low pressure transfer molding machine at a molding temperature of 175 ° C., a pressure of 70 kg / cm ² and a curing time of 120 seconds, and treated at 175 ° C. for 8 hours as an after-bake. After that, 24
The flexural strength at 0 ° C. was measured according to JIS K 6911. The unit is N / mm ² . Water absorption: A test disk (diameter 50 mm, thickness 4 mm) was molded using a low-pressure transfer molding machine at a molding temperature of 175 ° C., a pressure of 70 kg / cm ² , and a curing time of 120 seconds. After that, 150
Dry at 16 ° C for 16 hours, 85 ° C, 85% relative humidity
168 hours, the percentage of increase in weight relative to the initial weight was determined. Units%. Solder crack resistance: 80 pQFP (2 mm thick, chip size 9.0 mm × 9.0 mm) was molded using a low pressure transfer molding machine at a molding temperature of 175 ° C., a pressure of 70 kg / cm ² , and a curing time of 120 seconds, followed by after-baking. After treatment at 175 ° C for 8 hours, 85 ° C and relative humidity of 8
96 hours processing at 5%, IR reflow processing (24
(0 ° C., 10 seconds). Using an ultrasonic flaw detector, defects such as peeling and cracks inside the package were observed. The number of defective packages in the six packages is shown. High-temperature storage characteristics: using a low-pressure transfer molding machine, molding temperature 175 ° C., pressure 70 kg / cm ² , curing time 12
16pDIP in 0 seconds (chip size 3.0mm × 3.5
mm), and after-baked at 175 ° C. for 8 hours, subjected to a high-temperature storage test (185 ° C., 1000 hours).
The increased package was determined to be defective. The percentage defective in the 15 packages is shown as a percentage. Units%. Moisture resistance: Using a low-pressure transfer molding machine, 16pDIP (chip size: 3.0 mm × 3.5 mm) at a molding temperature of 175 ° C., a pressure of 70 kg / cm ² , and a curing time of 120 seconds.
Was molded. Thereafter, a pressure cooker test (125
C., 2.4 kg / cm ² ), and the failure occurrence time when the open failure of the circuit was measured every 50 hours was measured. The unit is time. Storage at 25 ° C .: After storing at 25 ° C. for 7 days, the spiral flow was measured and expressed as a percentage of the spiral flow immediately after adjustment. Units%.

(Examples 2 to 11, Comparative Examples 1 to 6)
According to the formulation in Table 2, an epoxy resin composition was obtained in the same manner as in Example 1, and evaluated in the same manner as in Example 1. The results are shown in Tables 1 and 2. The curing accelerator used in Examples 3 to 7, Example 11, Comparative Example 3, and Comparative Example 5 is a compound represented by Formula (5). The curing accelerator used in Comparative Examples 2 and 6 is: 1,8-diazabicyclo (5,4,0) undecene-7 (hereinafter referred to as DBU). The epoxy equivalent of the brominated bisphenol A type epoxy resin used in Comparative Example 1 was 365 g / eq. It is.

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[0029]

[Table 1]

[0030]

[Table 2]

[0031]

According to the present invention, an epoxy resin composition for semiconductor encapsulation which does not contain a halogen-based flame retardant and an antimony compound and has excellent moldability, rapid curability and fluidity can be obtained.
A semiconductor device using this is excellent in flame retardancy, high temperature storage characteristics, moisture resistance reliability, and solder crack resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 23/29 H01L 23/30 R 23/31 F term (Reference) 4J002 CC02X CC04X CC05X CC06X CC07X CD00W CD04W CD05W CD06W CD07W CD20W DE078 DE098 DE147 DJ007 DJ017 DJ047 DK009 EW176 FD017 FD138 FD139 FD156 FD160 FD200 GQ00 4J036 AA02 AC01 AC02 AC15 AD01 AD18 AF01 AF05 AF06 FA01 FA06 FA12 FB07 4M109 AA01 BA01 CA21 EA02 EB03 EC05

Claims (9)

[Claims] 1. An epoxy resin, (B) a phenolic resin, (C) a tetra-substituted phosphonium compound, (D) an inorganic filler, (E) a solid solution of a metal hydroxide represented by the general formula (1), and (F) An epoxy resin composition for semiconductor encapsulation, comprising zinc borate represented by the general formula (2) as an essential component. Mg _1-x M ²⁺ _x (OH) ₂ (1) (where M ²⁺ is Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu
Represents at least one kind of divalent metal ion selected from the group consisting of ²⁺ and Zn ²⁺ , and x represents a number of 0.01 ≦ x ≦ 0.5) pZnO · qB ₂ O ₃ · rH ₂ O (2) (where p, q, and r are positive numbers) 2. A compound represented by the general formula (3), a compound represented by the general formula (4), (G) a tetra-substituted phosphonium (X) and a phenolic hydroxyl group in one molecule. And a compound (Y) having two or more phenolic hydroxyl groups in one molecule and a conjugate base, wherein the conjugate base has two or more phenolic hydroxyl groups in one molecule. 2. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the compound is at least one selected from compounds comprising a phenoxide-type compound obtained by removing one hydrogen from a compound (Y) having at least one compound. 3. Embedded image (Wherein R _{1 to} R ₄ are the same or different groups selected from an alkyl group having 1 to 8 carbon atoms, a phenyl group or a substituted phenyl group) (Here, R ₅ is an alkyl group, a phenyl group, or a naphthyl group.) 3. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein M ^{2+ of the} metal hydroxide solid solution represented by the general formula (1) is Zn ²⁺ or Ni ²⁺ . 4. Zinc borate is 2ZnO.3B ₂ O _3.
3.5 H ₂ O at which claims 1-3 semiconductor encapsulating epoxy resin composition. 5. The compound (Y) having two or more phenolic hydroxyl groups in one molecule is selected from dihydroxybenzenes, trihydroxybenzenes, bisphenols, biphenols, dihydroxynaphthalenes, phenol novolak resins and phenol aralkyl resins. The epoxy resin composition for semiconductor encapsulation according to claim 2, which is at least one selected from the group consisting of: 6. A molecular aggregate comprising reacting a tetra-substituted phosphonium / tetra-substituted borate (Z) with a compound (Y) having two or more phenolic hydroxyl groups in one molecule at a high temperature, and further reacting the compound. The epoxy resin composition for semiconductor encapsulation according to claim 2, wherein the epoxy resin composition is obtained by a thermal reaction in a solvent having a boiling point of 60 ° C. or higher. 7. A molecular aggregate obtained by reacting a compound (Y) having two or more phenolic hydroxyl groups in one molecule, an inorganic base or an organic base, and a tetra-substituted phosphonium halide. Item 6. The epoxy resin composition for semiconductor encapsulation according to Item 2 to 5. 8. The epoxy resin composition for semiconductor encapsulation according to claim 2, wherein the tetra-substituted phosphonium (X) is tetraphenylphosphonium. 9. A semiconductor device comprising a semiconductor element encapsulated with the epoxy resin composition for semiconductor encapsulation according to claim 1.