JP2001261777A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] There is no gold wire flow, there is little warpage at room temperature and in the soldering process, and since it has excellent adhesion to an organic substrate, it has excellent reliability such as solder resistance and temperature cycle resistance. And obtaining an epoxy resin composition for semiconductor encapsulation suitable for an area mounting type semiconductor device. A group of polyfunctional epoxy resins represented by general formulas (1) and (2) and / or crystalline epoxy resins represented by general formulas (3) to (7) and having a melting point of 50 to 150 ° C. At least one or more epoxy resins selected from
A phenolic resin represented by the general formula (8), fused silica,
And a compound (Y) having two or more phenolic hydroxyl groups in one molecule and a conjugate base of the compound (Y), wherein the conjugate base is the compound (Y) An area-mount type epoxy resin composition for semiconductor encapsulation, comprising a curing accelerator comprising a phenoxide-type compound from which one hydrogen has been removed from hydrogen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called area mounting type semiconductor device in which a semiconductor element is mounted on one surface of a printed wiring board or a metal lead frame, and substantially only one of the mounting surfaces is resin-sealed. The present invention relates to a suitable epoxy resin composition for semiconductor encapsulation and a semiconductor device using the same.

[0002]

2. Description of the Related Art In recent years, in the market trend of miniaturization, weight reduction and high performance of electronic equipment, high integration of semiconductor elements has been progressing year by year, and surface mounting of semiconductor devices has been promoted. In recent years, area-mounted semiconductor devices have been developed, and are beginning to shift from semiconductor devices having conventional structures. A typical example of an area-mounted semiconductor device is a BGA (ball grid array) or a CSP (chip scale package) pursuing further miniaturization.
The surface-mount type semiconductor device represented by P has been developed in order to meet the demand for more pins and higher speed, which is approaching the limit. As the structure, on one side of a rigid circuit board represented by a BT resin / copper foil circuit board (bismaleimide / triazine resin / glass cloth board) or a flexible circuit board represented by a polyimide resin film / copper foil circuit board A semiconductor element is mounted, and only the semiconductor element mounting surface, that is, only one side of the substrate is molded and sealed with an epoxy resin composition or the like. Further, on the surface opposite to the semiconductor element mounting surface of the substrate, solder balls are formed two-dimensionally in parallel, and are characterized in that they are joined to a circuit board on which a semiconductor device is mounted. Further, as a substrate on which a semiconductor element is mounted, a structure using a metal substrate such as a lead frame has been developed in addition to the above-described organic circuit substrate.

The structure of these area-mounted semiconductor devices is as follows:
A single-sided sealing configuration is adopted in which only the semiconductor element mounting surface of the substrate is sealed with the epoxy resin composition and the solder ball forming surface is not sealed. On a metal substrate such as a lead frame, a sealing resin layer of about several tens of μm may be present even on the surface on which the solder ball is formed, but several hundred μm on the semiconductor element mounting surface.
Since a sealing resin layer having a thickness of about several mm is formed, substantially single-sided sealing is achieved. For this reason, these semiconductor devices may be affected by mismatch of thermal expansion and thermal shrinkage between the organic substrate or the metal substrate and the cured product of the epoxy resin composition, or the effect of curing shrinkage during molding and curing of the epoxy resin composition. In this case, warpage tends to occur immediately after molding. Further, when soldering is performed on a circuit board on which these semiconductor devices are mounted, 200
Although the semiconductor device undergoes a heating process at a temperature of ℃ or more, warping of the semiconductor device also occurs at this time, and many solder balls do not become flat and rise from the circuit board on which the semiconductor device is mounted, and the reliability of the electrical connection is reduced. Deteriorating problems occur.

In a semiconductor device in which substantially only one surface on a substrate is sealed with an epoxy resin composition, in order to reduce warpage, the thermal expansion coefficient of the substrate and the thermal expansion coefficient of a cured product of the epoxy resin composition are determined. Two approaches are important: approaching the same and reducing the amount of cure shrinkage of the cured product of the epoxy resin composition. As a substrate, an organic substrate has a high glass transition temperature (hereinafter, referred to as T) such as BT resin or polyimide resin.
g) are widely used and have a Tg higher than around 170 ° C., which is the molding temperature of the epoxy resin composition. Therefore, during the cooling process from the molding temperature to room temperature, the organic substrate contracts only in the region of the linear expansion coefficient (hereinafter referred to as α1). Accordingly, if the cured product of the epoxy resin composition has a high Tg, the same α1 as that of the organic substrate, and the curing shrinkage is zero, the warpage is considered to be almost zero. For this reason, a method has already been proposed in which Tg is increased by combining a polyfunctional epoxy resin and a polyfunctional phenol resin, and α1 is adjusted by the amount of the inorganic filler. However, the combination of a polyfunctional epoxy resin and a polyfunctional phenol resin has problems such as a decrease in fluidity and a reduction in a gold wire deformation rate.

[0005] When soldering is performed by soldering by means such as infrared reflow, vapor phase soldering, or solder immersion, moisture present inside the semiconductor device due to moisture absorption from the cured epoxy resin composition and the organic substrate. Cracks occur in the semiconductor device due to stress caused by rapid vaporization at high temperatures, and peeling may occur at the interface between the semiconductor element mounting surface of the organic substrate and the cured epoxy resin composition. In addition to low stress and low moisture absorption of products, adhesion to organic substrates is also required. Furthermore, due to the thermal expansion mismatch between the organic substrate and the cured product of the epoxy resin composition, peeling and cracking of the interface between the organic substrate and the cured product of the epoxy resin composition may occur even in a temperature cycle test, which is a typical example of a reliability test. appear. Conventional surface-mount type semiconductor devices such as QFP and SOP use a flexible epoxy resin such as a biphenyl-type epoxy resin to prevent cracks at the time of solder mounting and peeling at the interface of each material. Used in combination with a phenolic resin having an acidic skeleton,
Also, measures have been taken to reduce the moisture absorption by increasing the amount of the inorganic filler. However, with this approach,
Not only can the problem of warpage in a single-sided sealed semiconductor device not be solved, but also because the viscosity of the epoxy resin composition is high, gold wires flow during injection and the gold wires are short-circuited, which is a major problem. Was.

[0006]

DISCLOSURE OF THE INVENTION The present invention does not have a gold wire flow, has a small warpage after molding or soldering, and has particularly excellent adhesiveness to a substrate, so that the soldering resistance and the temperature cycle resistance are improved. An object of the present invention is to provide an epoxy resin composition for semiconductor encapsulation which is excellent and is suitable for an area mounting type semiconductor device, and a semiconductor device using the same.

[0007]

The present invention provides (A) a polyfunctional epoxy resin represented by the general formula (1) or (2) and / or a polyfunctional epoxy resin represented by the general formula (3) to (7): And the melting point is 5
At least one or more epoxy resins selected from the group of crystalline epoxy resins at 0 to 150 ° C., (B) a phenolic resin represented by the general formula (8), (C) fused silica,
And (D) a molecule comprising a tetra-substituted phosphonium (X) and a compound (Y) having two or more phenolic hydroxyl groups in one molecule and a conjugate base of a compound (Y) having two or more phenolic hydroxyl groups in one molecule. An aggregate wherein the conjugate base comprises a curing accelerator comprising a phenoxide-type compound obtained by removing one hydrogen from the compound (Y) having two or more phenolic hydroxyl groups in one molecule. An area mounting type epoxy resin composition for semiconductor encapsulation, and a semiconductor element mounted on one side of a substrate, and substantially only one side of the substrate side on which the semiconductor element is mounted is sealed using the epoxy resin composition. A semiconductor device which is stopped.

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[0008]

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[0009]

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[0010]

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[0011]

Embedded image (R in the formulas (1), (2), (7) and (8) is
A halogen atom or an alkyl group having 1 to 12 carbon atoms,
They may be the same or different. n is an average value and a positive number of 1 to 10, a is 0 or a positive integer of 1 to 4, b is 0 or a positive integer of 1 to 3, and c is 0
Or it is a positive integer of 1-2. R in the formulas (3) to (6) represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 12 carbon atoms, and may be the same or different. )

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Among the epoxy resins used in the present invention, an epoxy resin represented by the general formula (1) or an epoxy resin represented by the general formula (2), which is generally called a triphenolmethane type epoxy resin Is characterized by having a high cross-linking density, a high glass transition temperature, and a small curing shrinkage ratio of the cured product obtained by combining with the phenol resin of the general formula (8). The sealing of an area-mounted semiconductor device, which is an application of an object, is effective in reducing warpage. Specific examples of the general formulas (1) and (2) include the following, but are not limited thereto.

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[0013]

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The crystalline epoxy resin represented by the general formulas (3) to (7) and having a melting point of 50 to 150 ° C. is a diepoxy compound having two epoxy groups in one molecule or an oligomer thereof. . Since all of these epoxy resins exhibit crystallinity, they are solid at a temperature lower than the melting point, but become a low-viscosity liquid material at a temperature higher than the melting point. For this reason, the epoxy resin composition using these has a low viscosity in a molten state, so that it has a high fluidity at the time of molding and is excellent in the filling property of a thin semiconductor device. Therefore, it is preferable to use these crystalline epoxy resins when increasing the amount of the fused silica to reduce the moisture absorption of the cured product of the obtained epoxy resin composition and improving the soldering resistance. . These crystalline epoxy resins have as few as two epoxy groups in one molecule, and generally have only a low crosslink density and a cured product with low heat resistance. However, since it has a rigid planar or rod-like skeleton as a structure and has the property of being crystallized, that is, the feature that molecules are easily oriented, it is combined with a polyfunctional phenol resin represented by the general formula (8). When used, the heat resistance such as the glass transition temperature of the cured product is not easily reduced. Therefore, a semiconductor device sealed with an epoxy resin composition obtained by combining these crystalline epoxy resins and a phenol resin represented by the general formula (8) can reduce the amount of warpage. Further, in a temperature region once exceeding the glass transition temperature, a compound having a small number of functional groups exhibits a low elastic modulus, which is effective in reducing stress at a solder processing temperature. Therefore, there is an effect of preventing the occurrence of cracks in the soldering process and the occurrence of peeling off at the interface between the substrate and the cured product of the epoxy resin composition. When the crystalline epoxy resin has a melting point of less than 50 ° C., it is not preferable because fusion tends to occur in the production process of the epoxy resin composition and workability is significantly reduced. On the other hand, when the temperature exceeds 150 ° C., the epoxy resin composition is not sufficiently melted in the production process of heating and kneading, and thus has a problem that the uniformity of the material is inferior. The melting point is measured by a differential scanning calorimeter [SSC520 manufactured by Seiko Denshi Co., Ltd., heating rate 5 ° C.
/ Min] from the endothermic peak temperature. Hereinafter, specific examples of these crystalline epoxy resins will be described, but the present invention is not limited thereto.

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[0015]

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[0016]

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Further, from the viewpoints of achieving both high fluidity during molding, reduction in warpage of the semiconductor device, and soldering resistance during mounting, it is difficult to obtain a multi-layer structure represented by the above general formulas (1) and (2). 20 to 90% by weight of functional epoxy resin in total epoxy resin
And further represented by the general formulas (3) to (7) and having a melting point of 5
It is particularly preferred that the total epoxy resin contains a crystalline epoxy resin at 0 to 150 ° C. in an amount of 10% by weight or more. The epoxy resin of the present invention can be appropriately used in combination with another epoxy resin. The epoxy resin that can be used in combination is not particularly limited, and examples thereof include bisphenol F type epoxy resin, bisphenol A type epoxy resin, orthocresol novolac type epoxy resin, and naphthol type epoxy resin. Alternatively, they may be used in combination.

The phenolic resin represented by the general formula (8) used in the present invention is a so-called triphenolmethane-type phenolic resin. Specific examples are shown below, but are not limited thereto.

Embedded image When these phenolic resins are used, the crosslink density of the cured product is increased and a cured product having a high glass transition temperature is obtained, so that the warpage of the semiconductor device can be reduced. The phenolic resin of the general formula (8) of the present invention can be appropriately used in combination with another phenolic resin. Phenol resins that can be used together include
Although not particularly limited, for example, a phenol novolak resin, a cresol novolak resin, a naphthol novolak resin and the like can be mentioned, and these may be used alone or in combination.

The fused silica used in the present invention can be used either in a crushed form or a spherical form. However, in order to increase the amount of the fused silica and to suppress an increase in the melt viscosity of the epoxy resin composition, a spherical form is required. It is preferable to mainly use silica. In order to further increase the content of the spherical silica, it is desirable to adjust the particle size distribution of the spherical silica to be wider.

The molecular association, which is the curing accelerator (D) used in the present invention, includes a tetrasubstituted phosphonium (X), a compound (Y) having two or more phenolic hydroxyl groups in one molecule, and phenol in one molecule. A molecular association with a conjugate base of a compound (Y) having two or more neutral hydroxyl groups,
The conjugate base has two phenolic hydroxyl groups per molecule.
It is a phenoxide-type compound obtained by removing one hydrogen from a compound (Y) having at least one hydrogen atom. 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-butyltriphenylphosphonium, 2-hydroxyethyltriphenylphosphonium, trimethylphenylphosphonium,
Examples thereof include methyldiethylphenylphosphonium, methyldiallylphenylphosphonium, and tetra-n-butylphosphonium.

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, it is different from the conventional phosphonium-organic acid anion salt type compound in the structure of the molecule of the present invention. 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.

In the molecular aggregate of the present invention, a conventional curing accelerator can be appropriately used in combination. The curing accelerator that can be used in combination is not particularly limited.
General formula (9) disclosed in -295721,
A latent catalyst comprising a phosphonium borate represented by the general formula (10) and 1,8-diazabicyclo (5,4,
0) amine compounds such as undecene-7 and tributylamine; organic phosphorus compounds such as triphenylphosphine and tetraphenylphosphonium / tetraphenylborate; and imidazole compounds such as 2-methylimidazole. They may be used alone or as a mixture.

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The epoxy resin composition of the present invention comprises (A)
In addition to the component (D), if necessary, a coupling agent such as γ-glycidoxypropyltrimethoxysilane, a coloring agent such as carbon black, a brominated epoxy resin, a flame retardant such as antimony oxide, a phosphorus compound, and a silicone oil. And various additives such as a low-stress component such as silicone rubber, a natural wax, a synthetic wax, a higher fatty acid and a metal salt thereof, a releasing agent such as paraffin, and an antioxidant. The epoxy resin composition of the present invention comprises (A)
(D) The component and other additives are mixed at room temperature using a mixer, kneaded with a kneader such as a roll or an extruder, cooled, and pulverized. 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. In particular, the epoxy resin composition of the present invention is suitable for an area mounting type semiconductor device.

[0026]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited thereto. [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. It 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 D1. In addition, D1 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 (equivalent to compound (Y)) manufactured by Honshu Chemical Industry Co., Ltd. 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 taken out by filtration, and the product obtained by drying was designated as compound D2. The solvent as a heavy methanol, ¹ of D2 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 mixing ratio is by weight. << Example 1 >> 4.6 parts by weight of epoxy resin represented by the formula (11) [manufactured by Yuka Shell Epoxy Co., Ltd., Epicoat 1032H, softening point 60 ° C., epoxy equivalent 170] 4.6 parts by weight • formula (12) 4.6 parts by weight of a biphenyl type epoxy resin [YX-4000H, melting point 105 ° C, epoxy equivalent 195, manufactured by Yuka Shell Epoxy Co., Ltd.] MEH-7500, softening point 107 ° C., hydroxyl equivalent 97; 4.8 parts by weight, spherical fused silica 84.8 parts by weight, compound D1 0.4 part by weight, carnauba wax 0.5, manufactured by Meiwa Kasei Co., Ltd. Parts by weight ・ After mixing 0.3 parts by weight of carbon black with a mixer, the surface temperature was 90 ° C. and 4 parts by weight.
The mixture was kneaded 30 times using two rolls at 5 ° C., cooled and pulverized 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: Using a mold for spiral flow measurement according to EMMI-1-66, mold temperature 175
C., injection pressure was 70 kg / cm ² , and curing time was 2 minutes. The unit is cm. Glass transition temperature (Tg) and coefficient of linear expansion (α1): A test piece obtained by transfer molding at a mold temperature of 175 ° C., an injection pressure of 75 kg / cm ² for 2 minutes, and a further 175
The composition was post-cured at 8 ° C. for 8 hours, and measured using a thermomechanical analyzer (TMA-120, manufactured by Seiko Electronics Co., Ltd., heating rate 5 ° C./min). The unit of Tg is ° C, and the unit of α1 is ppm /
° C.・ Heat elastic modulus: The flexural modulus at 240 ° C.
It was measured according to 6911. The unit is N / mm ² . Curing shrinkage: mold temperature 180 ° C, injection pressure 75kg /
The test piece transfer molded in 2 cm ² was post-cured at 175 ° C. for 8 hours. The cavity dimensions of the mold heated to 180 ° C. and the dimensions of the molded article heated to 180 ° C. were measured using calipers, and the curing shrinkage was calculated as (molded article dimension) / (mold cavity dimension). Expressed as a ratio. Units%. Package warpage: 225-pin BGA package (substrate is a 0.36 mm thick BT resin substrate, package size is 24 × 24 mm, thickness 1.17 mm, silicon chip is 9 × 9 mm, thickness 0.35 mm, chip and circuit board Is bonded with a 25 μm diameter gold wire) at a mold temperature of 180 ° C. and an injection pressure of 7 μm.
Transfer molding was performed at 5 kg / cm ² for 2 minutes and post-cured at 175 ° C. for 8 hours. After cooling to room temperature, the displacement in the height direction was measured diagonally from the gate of the package using a surface roughness meter, and the value with the largest variation difference was defined as the amount of warpage. The unit is μm.・ Gold wire deformation rate: 22 formed by evaluation of package warpage amount
The 5-pin BGA package was observed with a soft X-ray fluoroscope, and the deformation rate of the gold wire was represented by the ratio of (flow amount) / (gold wire length).
Units%. Adhesion: A test piece of 2 × 2 × 2 mm is placed on a BT resin substrate at a mold temperature of 175 ° C. and an injection pressure of 70 kg / c.
m ² , 2 minutes of curing time, post-curing at 175 ° C. for 6 hours, 168 ° C. in a high-temperature and high-humidity bath at 85 ° C. and 85% relative humidity.
It was subjected to a moisture absorption treatment for an hour, and further subjected to an IR reflow treatment at 240 ° C. The shear adhesion between the cured product and the substrate was measured using Tensilon. The unit is kg / mm ² .

<< Examples 2 to 9, Comparative Examples 1 to 3 >> According to the formulations in Tables 1 and 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. Formula (1) used in Examples and Comparative Examples
The structures and properties of 1), the formula (12), the epoxy resins of the formulas (14) to (18), and the phenolic resins of the formulas (13) and (19) are shown below.

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[0031]

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[0032]

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An epoxy resin having a structure of the formula (14) as a main component: a melting point of 144 ° C. and an epoxy equivalent of 175; an epoxy resin having a structure of the formula (15) as a main component: a melting point of 52 ° C. and an epoxy equivalent of 225; Epoxy resin having a structure of formula (16) as a main component: melting point 133 ° C., epoxy equivalent 182 ・ Epoxy resin having a structure of formula (17) as a main component: melting point 82 ° C., epoxy equivalent 190, formula (18) Epoxy resin represented by: softening point 65 ° C,
Epoxy equivalent 210, phenol resin of formula (19): softening point 80 ° C., hydroxyl equivalent 104 104 The hardening accelerator used in Comparative Example 1 was triphenylphosphine, and the hardening accelerator used in Comparative Example 2 was 1, 8-diazabicyclo (5,4,0) undecene-7 (hereinafter DB)
U).

[Table 1]

[0034]

[Table 2]

[0035]

The epoxy resin composition for semiconductor encapsulation according to the present invention has no flow of gold wire, has a small warpage in the area mounting type semiconductor device using the same at room temperature and in the soldering step, and further has a good effect on the organic substrate. Because of its excellent adhesion, it has excellent reliability such as solder resistance and temperature cycle resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H01L 23/29 H01L 23/30 R 23/31 F-term (Reference) 4J002 CC06X CD03W CD04W CD05W CD07W CD12W DJ016 EW177 FD130 FD157 FD160 FD200 4J036 AA01 AC01 AC02 AC03 AC06 AD01 AD04 AD05 AD08 FA05 FA12 FB08 4M109 AA01 BA01 BA04 CA21 EA03 EB03 EB04 EB08 EB09 EB13 EC05 EC09

Claims (2)

[Claims] (A) a polyfunctional epoxy resin represented by the general formula (1) or (2) and / or a general formula (3) to
(7) at least one epoxy resin selected from the group of crystalline epoxy resins having a melting point of 50 to 150 ° C, (B) a phenolic resin represented by the general formula (8), (C) Fused silica, and (D) a conjugate base of tetra-substituted phosphonium (X), compound (Y) having two or more phenolic hydroxyl groups in one molecule and compound (Y) having two or more phenolic hydroxyl groups in one molecule Wherein the conjugate base comprises a curing accelerator consisting of a phenoxide-type compound obtained by removing one hydrogen from the compound (Y) having two or more phenolic hydroxyl groups in one molecule. Characteristic epoxy resin composition for area mounting type semiconductor encapsulation. Embedded image Embedded image Embedded image Embedded image Embedded image (R in the formulas (1), (2), (7) and (8) is
A halogen atom or an alkyl group having 1 to 12 carbon atoms,
They may be the same or different. n is an average value and a positive number of 1 to 10, a is 0 or a positive integer of 1 to 4, b is 0 or a positive integer of 1 to 3, and c is 0
Or it is a positive integer of 1-2. R in the formulas (3) to (6) represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 12 carbon atoms, and may be the same or different. ) 2. A semiconductor element is mounted on one side of a substrate, and substantially only one side on the substrate side on which the semiconductor element is mounted is sealed with the epoxy resin composition according to claim 1. A semiconductor device characterized by the above-mentioned.