JP2002069158A - Epoxy resin composition and semiconductor sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin composition which guarantees long term reliability without causing a resin cracking, and which is excellent in moisture resistance after mounting or soldering heat resistance, adhesiveness when mounted, while hygroscopicity is low, fluidity is good and moldability is excellent. SOLUTION: This epoxy resin composition containes a phenol compound shown by formula (A), a phenol compound show by formula (B), an epoxy resin shown by formula (C), an inorganic filler and a curing accelerator as essential components and is characterized by including the inorganic filler at 80-85 wt.% of a rate to the resin composition, and the semiconductor sealing device which is sealed by this curing material is provided.

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 having high adhesion, flame retardancy, low water absorption, excellent moldability, and excellent solder heat resistance, and a semiconductor chip sealed with the composition. Semiconductor sealing device.

[0002]

2. Description of the Related Art In order to protect semiconductor integrated circuits from mechanical and chemical actions, sealing resin compositions have been developed.
In recent years, ICs have become larger and more multi-polarized due to higher integration of chips, while the package outer diameter has been reduced and the mounting density on a substrate has been increased. In order to increase the mounting density, surface mounting of a semiconductor device is indispensable. When performing surface mounting, a technique such as IR reflow is used, but a semiconductor sealing device corresponding to this mounting method is required to have high solder heat resistance. The important thing about the solder heat resistance is the adhesion to various members inside the package,
Low water absorption of the resin composition. Therefore, the sealing resin composition has been made to have high adhesion to solve the problem, to increase the amount of the inorganic filler to reduce water absorption, and to add an adhesion promoter. However, this improvement also causes problems during molding. For example, there are drawbacks such as an increase in outer nests and inner nests, deformation of bonding wires, and insufficient filling in a thin package.

[0003] In addition, halogen-based flame retardants and the like have been used in conventional sealing resin compositions in order to maintain flame retardancy. However, from the environmental point of view, sealing resins containing no such flame retardants are used. Compositions are becoming a major need in the market. Similarly, due to environmental concerns, solders that do not use lead tend to be used, but by removing lead from the solder, the mounting temperature of semiconductor devices may be raised. Further, higher solder heat resistance is required.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and maintains high solder heat resistance, and has good fluidity and moldability and does not cause a change in wire. Another object of the present invention is to provide a sealing resin composition and a semiconductor sealing device having high flame retardancy without using a flame retardant auxiliary such as antimony or a halogen-based flame retardant.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve the above object, and as a result, by using a specific phenol compound and a specific epoxy resin,
The resin composition maintains high solder heat resistance and has good moldability by combining high fluidity.High flame retardancy without the use of flame retardant aids such as antimony or halogen-based flame retardants. It has been found that a resin composition having the following formula is obtained, and the present invention has been completed.

That is, the present invention provides: (A) a phenol compound represented by the following general formula:

Embedded image (Wherein, n represents an integer of 1 or more) (B) a phenol compound represented by the following general formula:

Embedded image (Wherein, n represents an integer of 1 or more) (C) an epoxy resin represented by the following general formula:

Embedded image (Wherein, R ¹ represents a methyl group, and R ² represents a hydrogen atom or a methyl group, respectively) (C) an inorganic filler and (D) a curing accelerator as essential components, and (D) An epoxy resin composition comprising an inorganic filler in a proportion of 80 to 95% by weight. Another aspect of the present invention is a semiconductor encapsulation device, wherein a semiconductor chip is encapsulated by a cured product of the epoxy resin composition.

Hereinafter, the present invention will be described in detail.

As the phenol compound used in the present invention, a phenol compound (A) represented by the above general formula (7) and a phenol compound (B) represented by the above general formula (8) are used in combination. Further, the component (A) and the component (B)
The mixing ratio of the components is 3: 1 to 20: 1 by weight, respectively.
It is desirable to mix in the ratio of. The sealing resin composition used alone with the phenol compound as the component (A) is inferior in workability due to low curability. Further, the sealing resin composition used alone with the phenol compound as the component (B) is not preferable because it has a large moisture absorption and impairs solder heat resistance.

The epoxy resin (C) used in the present invention is an epoxy resin represented by the general formula (9). Further, in addition to the epoxy resin (C), a novolak epoxy resin, a biphenyl epoxy resin, and other known epoxy resins can be used in combination.

As the inorganic filler (D) used in the present invention, generally used inorganic fillers are widely used. Among them, silica powder having a low impurity concentration and an average particle diameter of 30 μm or less is preferably used. Can be. If the average particle size exceeds 30 μm, the moisture resistance and the moldability are poor, which is not preferable. It is desirable that the blending ratio of the inorganic filler is 80 to 95% by weight based on the entire resin composition. If the proportion is less than 80% by weight, the moisture absorption rate of the resin composition becomes large, and the moisture resistance after solder immersion is inferior. .

As the (E) curing accelerator used in the present invention, DBU-based curing accelerators, phosphorus-based curing accelerators, imidazole-based curing accelerators, and other curing accelerators are widely used. These can be used alone or in combination of two or more. The mixing ratio of the curing accelerator is 0.1 to the resin composition.
It is desirable to mix them so as to contain from 01 to 5% by weight. If the proportion is less than 0.01% by weight, the gel time of the resin composition is long, the curing properties are deteriorated, and 5% by weight.
If it exceeds, the fluidity becomes extremely poor and the moldability is inferior, and the electrical properties also deteriorate, and the moisture resistance is inferior.

The epoxy resin composition of the present invention contains the above-mentioned specific phenolic compound, the specific epoxy resin, the inorganic filler and the curing accelerator as essential components. Depending on, for example, natural waxes, synthetic waxes, metal salts of linear fatty acids, release agents such as acid amides, esters and paraffins, coloring agents such as carbon black and red iron, silane coupling agents, rubber A system-based or silicone-based low stress imparting agent or the like can be appropriately added and blended.

As a general method for preparing the epoxy resin composition of the present invention as a molding material, a specific phenol compound, a specific epoxy resin, an inorganic filler, a curing accelerator and other components described above are added to a predetermined component. After blending the raw material components selected in the composition ratio and mixing them sufficiently uniformly with a mixer or the like, further perform a melting and mixing treatment with a hot roll or a mixing treatment with a kneader or the like, and then cool and solidify,
It can be pulverized to an appropriate size to obtain a molding material.
If the molding material thus obtained is applied to sealing, coating, insulating, etc. of electronic parts or electric parts such as semiconductor devices, excellent properties and reliability can be imparted.

The semiconductor sealing device of the present invention can be easily manufactured by sealing a semiconductor chip using the above-mentioned molding material. The semiconductor chip to be sealed is not particularly limited to, for example, an integrated circuit, a large-scale integrated circuit, a transistor, a thyristor, a diode, and the like. The most common sealing method is a low-pressure transfer molding method, but sealing by injection molding, compression molding, casting or the like is also possible. The molding material is heated and cured at the time of sealing, and finally a semiconductor sealing device sealed with the cured product is obtained. Curing by heating is 150
Desirably, the composition is cured by heating to a temperature of at least ℃. The substrate on which the chip is mounted is not particularly limited, such as ceramic, plastic, polyimide film, and lead frame.

[0015]

The epoxy resin composition and the semiconductor encapsulation device of the present invention use the specific phenol compound and the specific epoxy resin described above to reduce the water absorption of the resin composition and improve the flame retardancy. Also, by having high fluidity, good moldability is imparted, resin cracks after solder immersion and solder reflow are eliminated, and deterioration of moisture resistance is reduced.

[0016]

Next, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, “%” means “% by weight”.

Example 1 2.7% of the above-mentioned phenol compound of the formula 7, 0.5% of the phenol compound of the above-mentioned formula 8, 3,3 ', 5,5'-
Tetramethyl-4,4'-bis (2,3-epoxypropyloxy) diphenylmethane 4.0%, silica powder 9
2%, 0.2% of a curing accelerator, 0.2% of a natural wax and 0.4% of a silane coupling agent are mixed at room temperature, kneaded at 70 to 80 ° C, and cooled and solidified to form a molding material ( A) was prepared.

Example 2 3.3% of the phenol compound of the formula (7) used in Example 1, 0.7% of the phenol compound of the formula (8), 3,3 ', 5,5'-
4.9% of tetramethyl-4,4'-bis (2,3-epoxypropyloxy) diphenylmethane, silica powder 9
0%, a curing accelerator 0.2%, a natural wax 0.2% and a silane coupling agent 0.7% are mixed at room temperature, further kneaded at 70 to 80 ° C., and cooled and solidified to form a molding material ( B) was prepared.

Example 3 5.1% of the above-mentioned phenol compound of formula 7, 1.0% of the above-mentioned phenol compound of formula 8, 3,3 ', 5,5'-
7.6% of tetramethyl-4,4'-bis (2,3-epoxypropyloxy) diphenylmethane, silica powder 8
5%, a curing accelerator 0.4%, a natural wax 0.2% and a silane coupling agent 0.7% are mixed at room temperature, further kneaded at 70 to 80 ° C, and cooled and solidified to form a molding material ( C) was prepared.

Example 4 3.1% of the above-mentioned phenol compound of the formula (7), 0.6% of the phenol compound of the above-mentioned formula (8), 2,2 ', 3,3',
5,5'-hexamethyl-4,4'-bis (2,3-epoxypropyloxy) diphenylmethane 5.1%, silica powder 90%, curing accelerator 0.2%, natural wax 0.2% and silane cup 0.8% of a ring agent was mixed at room temperature, further kneaded at 70 to 80 ° C, and cooled and solidified to produce a molding material (D).

Comparative Example 1 Biphenyl type epoxy resin 4.9%, phenol aralkyl resin 3.9%, silica powder 90%, curing accelerator 0.
2%, natural wax 0.2% and silane coupling agent 0.8% were mixed at room temperature, kneaded at 70-80 ° C, and cooled and solidified to produce a molding material (E).

Comparative Example 2 Biphenyl type epoxy resin 7.7%, phenol aralkyl resin 6.2%, silica powder 85%, curing accelerator 0.1%
3%, natural wax 0.2% and silane coupling agent 0.6% were mixed at room temperature, kneaded at 70-80 ° C, and cooled and solidified to produce a molding material (F).

The molding materials (A) to (F) thus produced
Was transferred into a mold heated to 180 ° C. and cured to seal a semiconductor chip, thereby manufacturing a semiconductor sealing device. Various tests were performed on these semiconductor sealing devices, and the results are shown in Table 1. The epoxy resin composition and the semiconductor sealing device of the present invention have excellent fluidity, moisture resistance, and solder heat resistance. Thus, a remarkable effect of the present invention could be confirmed.

[0024]

[Table 1] * 1: A molded article having a diameter of 50 mm and a thickness of 3 mm was prepared by transfer molding, left in a saturated steam at 127 ° C. and 2.5 atm for 24 hours, and measured by the increased weight.

* 2: A molded article similar to that in the case of the water absorption was prepared, post-cured at 175 ° C. for 8 hours, a test piece of an appropriate size was measured using a thermomechanical analyzer.

* 3: Tested according to EMMI1-66.

* 4: Using a molding material, a silicon chip having two aluminum wirings bonded to a normal QFP frame was transfer molded at 180 ° C. for 1 minute, and then at 175 ° C. for 8 hours. Was post-cured. The molded article thus obtained was subjected to a moisture resistance test in saturated steam at 127 ° C. and 2.5 atm to evaluate the time at which 50% disconnection (defect occurrence) due to aluminum corrosion occurred.

* 5: A 60 × 60 mm dummy chip is QF
It was placed in a P (10 × 10 × 1.0 mm) package, transfer-molded at 180 ° C. for 1 minute using a molding material, and then post-cured at 175 ° C. for 8 hours. The semiconductor sealing device thus manufactured was subjected to a moisture absorption treatment at 85 ° C., 85% for 168 hours, and then subjected to IR reflow at 270 ° C. for 30 seconds to evaluate the occurrence of package cracks.

[0029]

As is clear from the above description and Table 1, the epoxy resin composition and the semiconductor encapsulation device of the present invention have good fluidity, excellent moldability, and solder heat resistance during mounting. It has excellent adhesion, good resin adhesion, excellent moisture resistance after mounting, and can guarantee reliability for a long period of time.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 CC032 CC042 CD051 DJ017 EJ016 EJ036 EJ046 EU118 EW138 FD017 FD142 FD146 FD158 4J036 AD08 DC41 FA05 FB08 4M109 AA01 BA01 BA03 BA05 CA21 EA03 EB03 EB04 EC20 EC05 EC05

Claims (2)

[Claims] (A) a phenolic compound represented by the following general formula: (Wherein, n represents an integer of 1 or more) (B) A phenol compound represented by the following general formula: (Wherein, n represents an integer of 1 or more) (C) an epoxy resin represented by the following general formula: (Wherein, R ¹ represents a methyl group, and R ² represents a hydrogen atom or a methyl group, respectively) (C) an inorganic filler and (D) a curing accelerator as essential components, and (D) An epoxy resin composition comprising an inorganic filler in a proportion of 80 to 95% by weight. (A) a phenolic compound represented by the following general formula: (Wherein, n represents an integer of 1 or more) (B) a phenol compound represented by the following general formula: (Wherein, n represents an integer of 1 or more) (C) an epoxy resin represented by the following general formula: (Wherein, R ¹ represents a methyl group, and R ² represents a hydrogen atom or a methyl group, respectively) (C) an inorganic filler and (D) a curing accelerator as essential components, and (D) A semiconductor sealing device, wherein a semiconductor chip is sealed with a cured product of an epoxy resin composition containing an inorganic filler in a ratio of 80 to 95% by weight.