JPS60179419A - Epoxy resin composition for semiconductor sealing - Google Patents

Abstract

PURPOSE:An epoxy resin composition for sealing a semiconductor device having an Al electrode, etc., excellent in moisture resistance and especially, galvanic corrosion resistance under applied voltage, containing an epoxy resin and a specified silane coupling agent. CONSTITUTION:The titled composition mainly consisting of an epoxy resin, a curing agent, an inorganic filler, and a silane coupling agent comprising a compound containing a gamma-glycido group and two alkoxyl groups (e.g., gamma-glycidoxypropylmethyldimethoxysilane). By using said silane coupling agent, it is possible to obtain an epoxy resin composition for sealing a semiconductor device having an Al electrode, etc., having high moisture resistance and, especially, excellent galvanic corrosion resistance under applied voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an epoxy resin composition for encapsulating a semiconductor having a metal electrode such as aluminum or the like.

In recent years, semiconductor devices such as transistor devices and integrated circuit devices have been widely encapsulated using heat-extensible resin compositions such as epoxy resins. This is because compared to hermetic methods using ceramic materials, the sealing operation is easier and more economical.However, on the other hand, resin sealing methods are more difficult to handle under high temperature and high humidity conditions than hermetic methods. It has the disadvantage of being less reliable.

In other words, the reason for the poor reliability at high temperatures and high temperatures is considered to be as follows. Since the epoxy resin molded body itself has water permeability, moisture that has entered the molded body will permeate through the surface cracks of the resin-sealed semiconductor element, causing corrosion, deterioration, and deterioration of metal electrodes such as aluminum. . In addition, at this time, the water dissolves mono-erodible ionic impurities such as Na+ and C6- contained in the epoxy resin molding, and transports them to the surface of the semiconductor element to promote metal corrosion. These ionic impurities are generated or mixed during the production of epoxy resins, etc., but it is difficult to completely remove them from the process. Besides these corrosive ionic impurities, epoxy resins contain hydrated molecules I/l! The amount of chlorine present is about 10 to 1000 times that of chlorine, which is an ionic impurity. These are not easily desorbed by moisture intrusion alone, but are ionized and eluted by the action of heat or a catalyst, which causes corrosion of aluminum electrodes and the like.

As described above, since the epoxy resin sealing method has problems with +11rt humidity and corrosion resistance, various attempts have been made to improve the reliability of resin sealing in the case. For example, selecting materials for resin compositions with few impurities (
% opening/closing No. 5.6-26926), moisture resistance and corrosion resistance of the molded body V
+: Considering curing accelerators that improve (
JP-A No. 56-158461), adding an anti-milk additive to the resin composition (JP-A-56-72045, JP-A-5
6-72046, JP-A-56-104926, JP-A-56-160056, JP-A-56-'160057
(No.), etc.

In response, the present inventors have conducted various studies in order to improve the moisture resistance reliability of semiconductor devices having aluminum electrodes etc. sealed with epoxy resin compositions. In particular, the silane cassilling agent used to improve the adhesion and water resistance of the interface between the lead frame, semiconductor element surface, or filler surface and resin, which is a factor that has a large impact on moisture resistance reliability. As a result, we found that a silane coupling agent containing an r-glycidoxy group and two alkoxy groups (hereinafter referred to as γ-glycidoxyalkyl dialkoxylan coupling agent) was used in an epoxy resin composition. The inventors have discovered that when a semiconductor using aluminum or an alloy containing aluminum as a main component is sealed with this addition, the moisture resistance reliability is significantly improved compared to other silane coupling agents. By adding a glycidoxyalkyldialkoxysilane cagging agent, the occurrence of defects such as disconnection due to corrosion of the aluminum 1y electrode is significantly reduced and suppressed compared to conventional methods in accelerated moisture resistance tests in high-temperature, high-pressure steam. It is possible to maintain and exhibit the required performance over a long period of time.In particular, in this accelerated test, the electrolytic corrosion resistance test in which a DC voltage was applied between the aluminum electrodes,
It turned out to have a very significant effect. This effect is
It can be considered as follows. Conventionally, silane coupling agents have received attention mainly for their interface reinforcing effects, but as a result of our studies, we have found that the silane coupling agents themselves have a tendency to enteric corrosion against metals, as well as moisture resistance reliability, especially electric resistance. It was found that this had a significant effect on eating habits. Among the silane coupling agents that have an interface reinforcing effect, γ-glycidoxyalkyldialkoxysilane coupling agents have very low corrosion resistance to aluminum compared to other agents, so they are highly reliable in terms of moisture resistance. In particular, this can be said to be a factor that significantly improved the electrolytic corrosion resistance. The number of alkoxy groups in this silane cassilling agent is 6.
If the number is more than 1, the reptophagy will greatly increase, and if there is only 1, the interface reinforcing effect will be decreased, which is undesirable. Therefore, only the combination of this γ-glycidoxy VQ and two alkoxy groups is
It was found that it has both an interface reinforcing effect and an anti-corrosion effect, and has a remarkable effect on improving moisture resistance reliability, especially electrolytic corrosion resistance.

Based on the above findings, the present invention provides a composition containing an epoxy resin, a curing agent, and an inorganic photonic agent as main components, and 14! The purpose of this invention is to provide an epoxy resin composition for sealing semiconductor devices having aluminum electrodes, etc., which has a high degree of moisture resistance, particularly excellent resistance to electrolytic corrosion under applied voltage, by adding JJ or 2 or more Keyaki.

That is, the present invention provides a composition comprising an epoxy resin, a curing agent, an inorganic filler, and a silane cutting agent as main components, wherein the silane cutting agent has an r-glycidoxy group and two alkoxy groups. It is characterized by containing a group.

The epoxy resin used in the present invention is not particularly limited in terms of molecular structure and molecular weight, as long as it has a small number of epoxy bonds (2 (III) or more) in its molecules.

, For example, hisphenol A qgq eboxii [
Examples include oil, phenol novolac type epoxy resin, and cresol lac type epoxy resin, but in this case, it is preferable to use one with less impurities and hydrolyzable chlorine.

Examples of the epoxy resin curing agent include phenolic novolak resins, phenol-based curing agents such as phenolic resin, amine thread softening agents, and acid anhydride curing agents.

There is no particular restriction on the amount of these used, but it is necessary to take into consideration the chemistry of the epoxy thread and the curing agent.

Furthermore, as an inorganic filler, for example, crystalline silica,
Examples include powders such as fused silica, calcium silicate, alumina, calcium sulfate, talc, barium sulfate, or lath fibers, but usually crystalline silica or fused silica is used. The blending ratio of these inorganic fillers to the whole varies depending on the selected resin content, but generally it is 150 to 45 parts by weight per 100 parts by weight of the resin content.
If it is about 0 parts by weight and less than 150 parts by weight, the expansion rate and molding yield rate will be high, and the yield rate will be low.
If the amount exceeds 0 parts, there are disadvantages such as decreased fluidity and increased mold wear.

The γ-glycidoxyalkyldialkoxysilane cagging agent to be added in the present invention is not particularly limited as long as it has a γ-glycidoxy group and two alkoxy groups.

In addition, one or a mixture of two or more selected from these may be used, for example, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxyzorobylmethyljethoxysilane. , r-glycidoxyglobylethyldiglopoquine silane, and the like. The addition lit of these silane cassilling agents per 10 weight parts of epoxy resin is 1.0 city fit: Ml - 15 weight - 1 liter: H1! t is preferable, and more preferably 1 to 2.0 parts by weight to 10 parts by weight. If the amount added is less than 1.0 parts by weight, no effect on moisture resistance or electrolytic corrosion resistance will be obtained, and if it exceeds 15 parts by weight, the moldability will be affected, such as a decrease in the hardness of the molded product.

Other components that may be added as necessary include epoxy resins, RS fuel agents such as antimony trioxide, pigments such as carbon black, and mold release agents such as montan wax, carnauba wax, or Hoechst wax nat.

Furthermore, 'Il!' of the epoxy resin composition according to the present invention! !
The preparation can be easily carried out by thoroughly mixing raw materials having a predetermined composition ratio using a mixer or the like, and then further melting and mixing them using a hot roll or a niegu.

Is this invention the following? : Length This will be explained in detail with examples.

Examples 1 to 5 In order to investigate the influence on the moisture resistance reliability of the γ-glycidoxyalkyldialkoxysilane coupling agent when sealed with a semiconducting epoxy resin composition having aluminum electrodes, etc., the following were carried out. A test was conducted and the results are shown in Table 1.

1) Corrosion test of silane cassilling agent against aluminum Aqueous solution of each γ-glycidoxydialkoxysilane cassilling agent shown in Table 1 (0,1-[.

/I//l, 0.5 mol/l, 1.0 mol/L//l)
Inside, aluminum pieces (0.5x 2.Ox 7.Oc.
m, 1.0 g) and placed it in an autoclave for 12
The corrosion resistance of a rutanium piece was evaluated based on the change in weight of the aluminum piece when boiled at 5°C for 24 hours.

2) +1 wet reliability test 15 parts by weight, phenolic novolac tree BW 50 M:
, Okibe, 1.0 parts by weight of triphenylphosphine, 2.5 parts by weight of carnauba wax, 1.0 parts by weight of carbon black, 210 parts by weight of ammonium trioxide, and the nail part and the fixing agent are shown in Table 1. SoQ in such a proportion.

After adding it, the mixture was mixed with a mixer, further kneaded with heated rolls, cooled and pulverized to produce five types of molding materials.

Using each of the resin compositions prepared in this way, an element having opposing aluminum wire electrodes was sealed by a transfer molding method. and temperature 12 for this sealed sample.
At 5°C and under steam pressure of 2.5 fi pressure, a bias voltage of 20 V DC was applied between the electrodes, and the open defect rate (disconnection rate) of the aluminum wire was measured over time. Moisture resistance reliability, particularly temperature resistance, was evaluated by comparing the results for each sample over time. At this time, the open defect rate was calculated from the number of defective pieces out of 50 pieces to be evaluated. From now on, this test will be done on the PC
It is called T (bias pressure test).

Comparative Examples 1 to 8 As comparative examples, one without the addition of a silane coupling agent and one with the addition of other silane coupling agents in the proportions shown in Table 2 were manufactured in the same manner as in the examples, and the same results were obtained. It was evaluated as follows.

Claims (1)

[Claims] A semiconductor packaging composition comprising an epoxy resin, a curing agent, an inorganic filler, and a silane coupling agent as main components, wherein the silane coupling agent contains a γ-glycid group and two alkoxy groups. Epoxy resin composition for stopping.