JPH0521652A - Semiconductor sealing epoxy resin composition - Google Patents

Abstract

PURPOSE:To provide clear markings which can be clearly recognized in a dark atmosphere and even if they are applied to a molded resin part of gray or black in the marking through a carbon dioxide gas YAG laser. CONSTITUTION:Semiconductor sealing epoxy resin is composed of essential components such as inorganic filler, epoxy resin, phenolic resin, curing accelerator, silicon compound, and anthraquinone black colorant (A), where 0.1-2.0% by weight of (A) component is contained.

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 a resin-sealed semiconductor device, which can make a clear marking on the surface by any laser marking device such as a carbon dioxide laser or a YAG laser.

[0002]

2. Description of the Related Art In recent years, due to environmental problems, the marking of resin-encapsulated semiconductor devices is carried out by using a freon or an ink marking that requires pre-cleaning with a chlorine-based solvent to emit a laser generated from a laser oscillator through a die-cut mask. There has been a shift to a laser marking method in which an image is focused on the semiconductor device and predetermined marking is performed or a character is directly drawn on the semiconductor device by a laser beam. Laser marking methods include pulse marking with a carbon dioxide gas laser (mask type), pulse marking with a YAG laser (mask type), and scanning marking (one-stroke writing).

In this marking method, the surface layer of the resin-sealed semiconductor device is several μm by the energy of the laser beam.
This is a method in which the surface is roughened by breaking to a depth of several tens of μm, and the marking is visually recognized by comparing the surface properties of the broken portion and the non-destructed portion. However, when marking is performed using a laser as described above, in the conventional resin-encapsulated semiconductor device, the comparison between the destructive portion and the non-destructive portion is not always good, and therefore, the marking is more difficult than the ink imprinting. Had a drawback that it could not be seen clearly.

The low-stress encapsulating material, which has become the mainstream in the recent trend of higher integration, is added with a silicone compound for the purpose of reducing stress, so that the marking is more unclear than the conventional material. There is a strong demand for improved visibility.

Under these circumstances, various studies have been made to improve the visibility, and it has been found that adjusting the components of the colorant is particularly effective. For example, a patent that a diazo dye or an azine dye is effective for improving visibility in carbon dioxide laser marking (for example, JP-A-60-1).
(Japanese Patent No. 19760) has also been filed. However, even if such a colorant shows a good marking with a carbon dioxide laser, it cannot absorb the laser energy at all with a YAG laser, and therefore the marking becomes completely invisible. This seems to be due to the difference in laser wavelength between the carbon dioxide laser and the YAG laser.

On the other hand, carbon black shows a good marking with a YAG laser, but has a drawback that visibility is poor with a carbon dioxide gas laser. At present, both the carbon dioxide gas laser marking machine and the YAG laser marking machine are used. Therefore, it is desired to develop an epoxy resin composition for semiconductor encapsulation which has good visibility with both laser types. As described above, none of the conventional epoxy resin encapsulating materials shows good visibility in both the carbon dioxide laser marking and the YAG laser marking laser types.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and a carbon dioxide gas laser marking machine, Y
It is intended to provide an epoxy resin composition for semiconductor encapsulation, in which marking can be clearly seen by a laser even when the marking is carried out by any of the AG laser marking machines in a relatively dark atmosphere, and the resin molding portion is gray or black.

[0008]

That is, the present invention comprises an inorganic filler, an epoxy resin, a phenol resin, a curing accelerator, a silicone compound and a mixture of compounds represented by the following formulas (1), (2) and (3). An anthraquinone-based black colorant as an essential component and an epoxy resin composition for semiconductor encapsulation containing 0.1 to 2.0% by weight of the anthraquinone-based black colorant in the entire resin composition.

[0009]

[Chemical 2]

That is, as the epoxy resin composition, a thermosetting resin, particularly one containing an epoxy resin as a main component, has been widely used. A resin composition containing such an epoxy resin as a main component generally contains, in addition to the epoxy resin,
Usually, a curing agent, a curing accelerator, a filler, and a release agent are blended, and if necessary, a flame retardant, a coloring agent, a coupling agent and the like are blended. As the pigment, carbon black or diazo dye is usually used. In the resin-sealed semiconductor device obtained by sealing using such a resin composition,
As described above, in both the carbon dioxide gas and YAG lasers, the destructive portion and the non-destructive portion on the surface of the semiconductor device due to the laser beam cannot be said to be clear and the marking cannot be clearly seen.

The present inventor has carried out research for the purpose of obtaining a sharp contrast between a destructive portion and a non-destructive portion on the surface of a semiconductor device by laser light, and as a result, it has been found that the anthraquinone colorant has a great influence. As a result of further research focusing on this dye, formulas (1), (2), and (3)
Anthraquinone-based black colorant consisting of a mixture of compounds shown in (hereinafter referred to as anthraquinone-based black colorant)
It was found that the contrast between the destructive part and the non-destructive part becomes clear when marking with any laser. As a result of further research based on this, 0.1% of the anthraquinone-based black colorant was added to the entire resin composition.
The content of up to 2.0% by weight (hereinafter, abbreviated as%) particularly improves the sharpness of the marking, and even if the resin-molded portion of the semiconductor device is colored such as gray or black, it is a relatively dark atmosphere. The inventors have found that the markings can be clearly recognized even underneath and have reached the present invention.

The encapsulating epoxy resin composition of the present invention contains an epoxy resin, a phenol resin, a curing accelerator, a silicone compound, an inorganic filler such as fused silica or crystalline silica, and an anthraquinone-based mixed black colorant as essential components. In addition, if necessary, a silane coupling agent, a brominated epoxy resin, a flame retardant such as antimony trioxide, hexabromobenzene, a release agent such as a natural wax or a synthetic wax, and various additives are appropriately mixed. There is no problem.

In order to produce the encapsulating epoxy resin composition of the present invention as a molding material, the epoxy resin, the phenol resin, the curing accelerator, the silicone compound, the filler, and other additives are sufficiently homogenized by a mixer or the like. Then, the mixture can be melt-kneaded with a hot roll or a kneader, cooled, and then pulverized to obtain a molding material.

These molding materials can be applied to electronic parts or sealing, coating and insulation of electronic parts. The epoxy resin used in the present invention is not particularly limited in molecular structure, molecular weight and the like as long as it is a compound having at least two epoxy groups in its molecule, and it is generally used as a sealing material, For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin,
Bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy type epoxy resin, glycidyl ester type epoxy resin, diglycidyl amine type epoxy resin, isocyanurate type epoxy resin, bisphenol A or bisphenol F Examples thereof include glycidyl ether compounds of polycondensation products of and formaldehyde, and their halides and hydrogenated compounds. These may be used alone or in combination of two or more.

Further, as a phenol resin as a curing agent,
Examples of the novolak type phenol resin system and modified resins thereof include phenol novolac, O-cresol novolac, and alkyl-modified phenol novolac resin. These may be used alone or in combination of two or more kinds. Absent.

The compounding ratio of the epoxy resin and the curing agent is such that the equivalent ratio of the epoxy group of the epoxy resin and the hydroxyl group of the curing agent is 0.5.
It is desirable to be in the range of -5. If the equivalent ratio is less than 0.5 or exceeds 5, moisture resistance, molding workability, and electrical characteristics of the cured product deteriorate, which is not preferable.

The curing accelerator used in the present invention may be any one as long as it accelerates the reaction between the epoxy group and the phenolic hydroxyl group, and those generally used for sealing materials can be widely used. For example, diazabicycloundecene (DBU), triphenylphosphine (TPP), dimethylbenzylamine (BDMA), 2-methylimidazole (2MZ) and the like are used alone or in combination of two or more.

Examples of the filler used in the present invention include fused silica, crystalline silica, alumina, silicon nitride and magnesium oxide, which may be used alone or in combination of two or more. Examples of the silicone compound include silicone oil, silicone rubber, and silicone gel, which may be used alone or in admixture of two or more, and are added to impart low stress to the epoxy resin composition. Anthraquinone-based mixed black colorant is used as the colorant, and this colorant has the formula (1), (2),
It is a fine powder dye mixture containing the three compounds shown in (3).

This anthraquinone-based mixed black colorant is contained in the composition in an amount of 0.1 to 2.0%, more preferably 0.1.
It is better to contain 3 to 1.5%. That is, when the amount of this anthraquinone-based mixed black colorant added is less than 0.1%, the contrast between the destructive portion and the non-destructive portion becomes unclear, and conversely, when the amount exceeds 2%, the resin-encapsulated semiconductor device. This is because it causes a defect such as a decrease in reliability (moisture resistance).
In particular, when the content of the anthraquinone-based mixed black colorant is set to 0.3 to 1.5%, the marking becomes remarkably clear. The anthraquinone-based mixed black colorant contains 5% by weight of any of the compounds of formulas (1), (2) and (3).
Must be included. Even if one kind of compound is less than 5% by weight, desired blackness cannot be obtained. In addition to the above colorant, a colorant conventionally added to the resin composition, such as carbon black, may be used. As described above, the use of this anthraquinone-based mixed black colorant as a colorant is a major feature of the present invention, which allows clear marking even in a relatively dark atmosphere or when the resin molding portion is gray or black. Will be done.

The present invention will be specifically described below with reference to examples.

[0021]

Example 1 Fused silica 68.0 parts by weight O-cresol novolac epoxy resin 16.0 parts by weight (epoxy equivalent 200, softening point 65 ° C.) phenol novolac resin 9.0 parts by weight (OH equivalent 104, softening point 100 ° C.) brominated bisphenol A type epoxy resin 1.7 parts by weight (Br content 46%, epoxy equivalent 360) DBU 0.2 parts by weight Antimony trioxide 1.7 parts by weight Carnova wax 0.3 parts by weight Silicone oil 3.0 parts by weight (SF-8413, Toray Dow Corninda Silicone) 0.8 parts by weight of γ-glycidmethoxysilane 0.15 parts by weight of anthraquinone-based mixed black colorant were mixed at room temperature with a mixer, kneaded at 70 to 100 ° C. with a biaxial roll, cooled, and ground to obtain a molding material.

The obtained molding material was made into tablets, which were then transferred to a low-pressure transfer molding machine at 175 ° C., 70 kg / cm ² , 1
Sealed in a 16p DIP package under the condition of 20 seconds, 175 ℃,
After post-curing under the condition of 8 hours, laser marking was performed and the visibility was evaluated using a 21-step sensitivity guide.

As a laser marking machine, carbon dioxide gas laser mark 940 type manufactured by Lumonix and YA manufactured by NEC are used.
G laser mark SL-476A was used.

Examples 2 to 4 A molding material was obtained in the same manner as in Example 1 except that the compounding amount of the anthraquinone-based black colorant was changed. A product was prepared and a laser marking test was conducted. The test results are shown in Table 1.

Comparative Examples 1 to 4 Resin compositions were prepared in the same manner as in Example 1 with the compounding ratios shown in Table 2 and tested in the same manner. The results are shown in Table 2.

[0026]

[Table 1]

[0027]

[Table 2]

[0028]

According to the present invention, the resin-encapsulated semiconductor device to be covered and molded can be clearly identified even when the resin-molded portion is gray, black, or the like, or in a dim atmosphere when the marking is formed by laser light. Marking that can be done will be possible, and the sharpness of marking will be greatly improved.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C08K 5/16 NLB 7167-4J C08L 63/00 NKB 8416-4J

Claims (1)

Claims: 1. An anthraquinone system comprising an inorganic filler, an epoxy resin, a phenol resin, a curing accelerator, a silicone compound and a mixture of compounds represented by the following formulas (1), (2) and (3). The black colorant is an essential component, and the anthraquinone-based black colorant is contained in the entire resin composition in an amount of 0.1 to 0.1%.
An epoxy resin composition for semiconductor encapsulation, comprising 2.0% by weight. [Chemical 1]