JP2001206933A - Resin composition for sealing use and semiconductor- sealed device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject resin composition having a good flowability/ formability and soldering heat resistance in its mounting, causing no resin cracking, high in adhesivity, excellent in moisture resistance after mounted, and securing its long-term reliability, and to provide semiconductor-sealed devices using the above resin composition. SOLUTION: This resin composition for sealing use essentially comprises (A) a phenolic resin curing agent modified with a condensed polycyclic aromatic hydrocarbon such as naphthalene or anthracene, (B) an epoxy resin, (C) 25-95 wt.% of an inorganic filler and (D) a curing promoter. The other objective semiconductor-sealed devices are such that the semiconductor chips are sealed with the cured product of the above resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing resin composition having high adhesion, high strength, low water absorption, excellent moldability and soldering heat resistance, and a semiconductor sealing device.

[0002]

2. Description of the Related Art In order to protect semiconductor integrated circuits and the like 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, while the outer diameter of packages has been reduced. Therefore, high solder heat resistance is required for a device for surface mounting, which has a great need in the market. What is important for the solder heat resistance is the improvement of the adhesion to various members inside the package and the strength of the resin composition itself. In order to solve the problems, the sealing resin composition has been made to have high adhesion, high strength, and low water absorption by increasing the amount of an inorganic filler and adding an adhesion promoter. However, on the other hand, there has been a result that defects at the time of molding are likely to occur. For example, there are disadvantages such as an increase in outer nests and inner nests, deformation of bonding wires, and insufficient filling in thin packages.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned drawbacks. The present invention maintains high solder heat resistance during mounting, and has good fluidity and moldability, and is capable of deforming a wire. It is an object of the present invention to provide a sealing resin composition and a semiconductor sealing device which do not cause the problem.

[0004]

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 resin as a curing agent for an epoxy resin composition, the coefficient of thermal expansion thereof has been reduced. Reduced, high fluidity, excellent mechanical properties, the resulting semiconductor encapsulation device is solder immersion,
The inventors have found that there is no occurrence of resin cracks after solder reflow, and have completed the present invention.

That is, the present invention provides (A) the following formula:
Phenolic resin curing agent modified with condensed polycyclic aromatic hydrocarbon,

Embedded image (However, in the formula, R represents any condensed polycyclic aromatic ring such as naphthalene or anthracene, n represents an integer of 1 or more, and when n is 2 or more, Rs may be the same or different.)
(B) epoxy resin, (C) inorganic filler and (D)
A sealing resin composition comprising a curing accelerator as an essential component and the inorganic filler (C) in a proportion of 25 to 95% by weight based on the resin composition. A semiconductor sealing device, wherein a semiconductor chip is sealed with a cured product of a resin composition for stopping.

Hereinafter, the present invention will be described in detail.

As the (A) phenol resin curing agent modified with the condensed polycyclic aromatic hydrocarbon used in the present invention, those represented by the above-mentioned general formula 3 are used. Specifically, for example,

Embedded image These can be used alone or in combination of two or more. In addition, a novolak phenol resin, an aralkyl phenol resin, and other known phenol resins can be used in combination with the modified phenol resin.

As the epoxy resin (B) used in the present invention, novolak epoxy resins, biphenyl epoxy resins, and other known epoxy resins can be used in combination.

As the inorganic filler (C) used in the present invention, generally known 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. The inorganic filler is desirably contained in a proportion of 25 to 95% by weight based on the whole resin composition. If the proportion is less than 25% by weight, the moisture absorption of the resin composition becomes large, and the moisture resistance after solder immersion is inferior. If it exceeds 95% by weight, the fluidity becomes extremely poor, and the moldability deteriorates, which is not preferable. .

As the (D) 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. More than one species can be used in combination.
It is desirable to mix the curing accelerator so that it is contained in an amount of 0.01 to 5% by weight based on the entire resin composition. If the proportion is less than 0.01% by weight, the gel time of the resin composition will be long and the curing properties will be poor. It is unfavorable because it deteriorates and has poor moisture resistance.

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

As a general method for preparing the encapsulating resin composition of the present invention as a molding material, the above-mentioned specific phenol resin curing agent, epoxy resin, inorganic filler and curing accelerator, and other components are used. After mixing the raw materials selected in a predetermined composition ratio and mixing them sufficiently uniformly with a mixer or the like, further performing a melt-mixing treatment with a hot roll or a kneading treatment with a kneader or the like, and then solidifying by cooling and pulverizing to an appropriate size. To form a molding material. If the molding material thus obtained is applied to coating, insulation, etc. of electronic parts or electric parts such as semiconductor devices, excellent properties and reliability can be imparted.

The semiconductor encapsulation device of the present invention can be easily manufactured by encapsulating 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 ℃. Substrates for mounting chips include ceramics, plastics,
Examples include, but are not limited to, polyimide films and lead frames.

[0014]

The sealing resin composition and the semiconductor sealing device of the present invention use the above-mentioned specific phenol resin to reduce the coefficient of thermal expansion of the resin composition and to fill the inorganic filler with a high amount. By having high fluidity even after the formation, the thermo-mechanical properties are improved, the occurrence of resin cracks after solder immersion and solder reflow is eliminated, and deterioration of moisture resistance is reduced.

[0015]

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 FPI-5127 (trade name, manufactured by Kashima Oil Co., Ltd.) as the above-mentioned condensed polycyclic aromatic modified phenolic resin of Chemical Formula 3
4.0%, biphenyl epoxy resin 5.0%, silica powder 90%, curing accelerator 0.2%, ester wax 0.
3% and 0.5% of the silane coupling agent were mixed at room temperature, kneaded at 90 to 95 ° C, and cooled and solidified to produce a molding material (A).

Example 2 As in Example 1, FPI-5127 (manufactured by Kashima Oil Co., Ltd.) was used as the condensed polycyclic aromatic modified phenol resin of Chemical Formula 3.
Trade name) 4.0%, Novolak epoxy resin 5.0%,
90% of silica powder, 0.2% of curing accelerator, 0.3% of ester wax and 0.5% of silane coupling agent are mixed at room temperature, kneaded at 90-95 ° C, solidified by cooling and molding. Material (B) was produced.

Comparative Example 1 4.0% phenol aralkyl resin, 5.0% biphenyl epoxy resin, 90% silica powder, 0.2 curing accelerator
%, Ester wax 0.3% and silane coupling agent 0.5% were mixed at room temperature, kneaded at 90-95 ° C., and cooled and solidified to produce a molding material (C).

Comparative Example 2 Phenol aralkyl resin 4.0%, novolak epoxy resin 5.0%, silica powder 90%, curing accelerator 0.2
%, Ester wax 0.3% and silane coupling agent 0.5% were mixed at room temperature, kneaded at 90-95 ° C., and cooled and solidified to produce a molding material (D).

The molding materials (A) to (D) 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.

[0021]

[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 was prepared in the same manner as in the case of the water absorption rate, post-cured at 175 ° C. for 8 hours, and a test piece having an appropriate size was measured using a thermomechanical analyzer.

* 3: Tested according to JIS-K-6911.

* 4: Using a molding material, a silicon chip having two aluminum wirings was bonded to a normal 42 alloy frame, transfer-molded at 180 ° C. for 1 minute, and after 8 hours at 175 ° C. Curing was performed. The molded product 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 6.0 × 6.0 mm dummy chip is placed in a QFP (14 × 14 × 1.0 mm) package.
After transfer molding at 180 ° C. for 1 minute using the molding material, post-curing was performed at 175 ° C. for 8 hours. After the thus-manufactured semiconductor sealing device is subjected to a moisture absorption treatment at 85 ° C. and 85% for 168 hours, IR reflow at 240 ° C. is performed for 30 minutes.
The test was performed for 2 seconds to evaluate whether or not a package crack occurred.

[0026]

As apparent from the above description and Table 1, the encapsulating resin composition and the semiconductor encapsulating apparatus of the present invention are:
The fluidity is good, the moldability is excellent, the moisture resistance at the time of mounting and the solder heat resistance are excellent, and there is no resin crack. As a result, long-term reliability can be guaranteed.

Claims (2)

[Claims] (A) A phenol resin curing agent modified with a condensed polycyclic aromatic hydrocarbon represented by the following formula: (However, in the formula, R represents any condensed polycyclic aromatic ring such as naphthalene or anthracene, n represents an integer of 1 or more, and when n is 2 or more, Rs may be the same or different.)
(B) epoxy resin, (C) inorganic filler and (D)
A sealing resin composition comprising a curing accelerator as an essential component and the inorganic filler (C) in a proportion of 25 to 95% by weight based on the resin composition. (A) a phenol resin curing agent modified with a condensed polycyclic aromatic hydrocarbon represented by the following formula: (However, in the formula, R represents any condensed polycyclic aromatic ring such as naphthalene or anthracene, n represents an integer of 1 or more, and when n is 2 or more, Rs may be the same or different.)
(B) epoxy resin, (C) inorganic filler and (D)
A semiconductor chip is sealed with a cured product of a sealing resin composition containing a curing accelerator as an essential component and (C) the inorganic filler in a ratio of 25 to 95% by weight based on the resin composition. A semiconductor encapsulation device, comprising: