JPS60226144A - Resin-sealed type semiconductor device - Google Patents

Abstract

PURPOSE:To improve the reliability of titled device at high temperature and high humidity by a method wherein aluminum and/or aluminium alloy as electrode and wiring member are processed in water solution with specific pH value preliminarily containing antimony oxide and aminosilane compound to be sealed with resin. CONSTITUTION:When the surface of aluminum and/or aluminium alloy as electrode and wiring member is processed in water solution with specific values of pH 3-9 containing antimony oxide and aminosilane compound, corrosion protective covering containing said compounds is formed on the surface to improve the moisture proof reliability. As for the aminosilane compound, e.g. gamma- aminopropyltriethoxysilane etc. is applicable. The process solution composed of antimony oxide and aminosilane compound added to pure water may be thoroughly agitated and mixed under heating condition at 60-100 deg.C to adjust the pH value thereof by means of adding organic or inorganic acid thereto as necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a resin-sealed semiconductor device that has excellent reliability, particularly under high temperature and high humidity conditions.

[Background of the invention]

In recent years, diodes, thyristors, transistors, integrated circuits, large-scale integrated circuits, and electronic components equipped with these various semiconductor devices have been packaged.

However, since general plastic materials are flammable, the plastic materials used for packaging the various electronic components listed above are blended with various halogenated compounds, phosphorus compounds, antimony oxide, or inorganic hydroxides to make them flame-retardant. This increases the safety of combustion in the event of electronic component failure.

In particular, epoxy resin compositions are usually used for packaging semiconductor devices that require a high degree of reliability, but their flame retardance is generally achieved by using a combination of halogenated epoxy resin and antimony oxide. .

By the way, general semiconductor devices are extremely sensitive to moisture and chemical contamination, and in particular, semiconductor devices that use aluminum or aluminum alloy for wiring are susceptible to minute amounts of contaminants contained in the package material and from outside the package. Interaction with infiltrating moisture can corrode the wiring, causing wire breakage and abnormal leakage current. This tendency is -+1jJ++-sfshi+#L+-'WbstrictJ
/) This is particularly noticeable for ml N4da4 Kage Inushita + 1f-MLj'.

To solve these problems, various methods have been used to refine various materials to reduce contaminants, reduce the moisture permeability of packaging materials to prevent moisture infiltration, and improve the
Although various efforts have been made to improve the adhesion or adhesion between lead wires, lead frames, etc. and package materials, there is a problem in that the moisture resistance of plastic package products is considerably inferior to that of hermetically sealed products.

(Objective of the Invention) An object of the present invention is to improve the above-mentioned drawbacks of the prior art and to provide a resin-sealed semiconductor device which has excellent reliability particularly under high temperature and high humidity conditions.

[Summary of the invention]

The present invention uses aluminum and/or aluminum as electrodes and wiring members.
Or 4, in a resin-sealed semiconductor device using an aluminum alloy, aluminum and/or aluminum alloy as electrodes and wiring members are treated in advance with an aqueous solution of pH 3 to 9 containing antimony oxide and an aminosilane compound, and then It is characterized by sealing the semiconductor element with resin.

The present inventors conducted various studies on the corrosion mechanism of aluminum and/or aluminum alloy of resin-sealed semiconductor devices under high temperature and high humidity, and countermeasures against the corrosion. As a result, corrosion of aluminum and/or aluminum alloy in resin-sealed semiconductor devices is caused not only by moisture and contaminants mentioned above, but also by the soldering process of the encapsulated product or thermal decomposition that does not adhere under high-temperature, high-humidity test conditions. It has become clear that the corrosion of aluminum and/or aluminum alloys is significantly accelerated by the presence of antimony dioxide, which is used as one of the flame retardant components, and involves trace amounts of halogens and organic acid compounds. However, at the current technological level, it is nearly impossible to completely eliminate these factors that affect the corrosion of aluminum and/or aluminum alloys from sealing resin compositions. Therefore, the present inventors investigated a corrosion prevention method that can suppress corrosion of aluminum and aluminum alloys even under such circumstances. As a result, in the preprocess of resin-sealing semiconductor elements, aluminum and/or the surface of aluminum used as electrodes and wiring members is treated with an aqueous solution of pH 3 to 9 containing antimony oxide and an aminosilane compound. Alternatively, the inventors have discovered that an anti-corrosion film containing antimony oxide and an aminosilane compound is formed on the surface of an aluminum alloy, thereby significantly improving the moisture resistance reliability of resin-sealed semiconductor elements, and have thus arrived at the present invention. The chemical structure of the above-mentioned anti-corrosion coating component is currently being analyzed and the details are unknown, but as will be described later, the infrared absorption spectrum of the coating is completely different from that of antimony oxide and aminosilane compounds. Furthermore, the presence of antimony (sb) and silicon (Si) has been confirmed from the X-ray spectrum.

The antitine oxide used in the present invention refers to antimony dioxide, but in addition to antimony tetroxide, aminosilane compounds include γ-aminopropyltriethoxysilane, N-β(aminoethyl)-γ-aminopropyltrimethoxy Silane, γ-nyreidopropyltriethoxysilane, n-(dimethoxymethylsilylpropyl)ethylenediamine, etc. can be used.

When performing surface treatment of aluminum and/or aluminum alloy as electrodes and wiring members using these compounds, the treatment liquid composition and treatment conditions are not particularly limited. However, in order to satisfactorily achieve the purpose of the present invention, the treatment solution should be prepared by adding 0.01 to 5 g each of antimony oxide and aminosilane compounds to about 100 g of pure water.
Stir and mix thoroughly under heating conditions of 0 to 100°C, and add inorganic or organic acid as necessary to adjust the pH of the treatment solution to 3.
It is desirable to use one adjusted to a range of 9 to 9, preferably 4 to 7. In addition, the antimony oxide and aminosilane compounds used in the present invention contain especially carbon as ionic impurities.
Halogen ion content such as Q- and Br- is 110
It is desirable to use 000 or less, preferably 10 ppm or less.

Next, the sealing resin composition used in the present invention may generally be an epoxy resin composition using a phenol resin, an acid anhydride, an amine compound, etc. as a curing agent, but if necessary, other than epoxy resin may be used. In addition, thermosetting resin compositions such as vinyl ester resins, unsaturated polyester resins, silicone resins, and polyimide resins, and thermoplastic resin compositions such as polyphenylene sulfide and polysulfone may be used. These resin compositions also contain flame retardant components such as halogenated compounds such as brominated epoxy resins, antimony oxide, phosphorus compounds, and nitrogen compounds, as well as curing accelerators, silica, alumina, and glass fibers, as necessary. Fillers such as fillers, flexibilizing agents, coupling agents, mold release agents, surfactants, pigments, dyes, etc. can also be blended.

Note that even in the resin-sealed semiconductor device of the present invention, if a large amount of contaminants are present in the resin composition, corrosion of aluminum and/or aluminum alloy as electrodes and wiring members progresses. Therefore, it is desirable that the amount of contaminants in the resin composition be as low as possible2. For example, when the Log of the resin composition is extracted with 100 cc of pure water at 12.0°C for about 100 hours, the extracted water It is desirable that the electrical conductivity is 200 μv/am or less.

Compared to semiconductor devices sealed using conventional methods, the semiconductor devices obtained in this way are highly reliable because electrodes and wiring members made of aluminum or aluminum alloy are extremely unlikely to be corroded, especially under high temperature and high humidity conditions. Improve dramatically.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in more detail with reference to aluminum surface treatment examples and examples, but the present invention is not limited thereto. In addition, in each example, when the amount of each material is expressed as part, it means part by weight.

[Treatment Example 1] 0.5 g of γ-nyreidopropyltriethoxysilane (manufactured by Nippon Unicar Co., Ltd., A-1160) at 80~
Mixed with 50g of pure water heated to 98℃ and cooled, a pure aluminum wire of φ30μm and 2% silicon were placed in this solution.
The compounded aluminum wire was immersed for 1 minute at room temperature and then dried in a chamber for 24 hours.

[Treatment example 2] Niantimony trioxide (manufactured by Wako Pure Chemical Industries, reagent grade) 0.5 g
mixed with pure water heated to 80-98℃.

The same pure water aluminum wire and 2% silicon-containing aluminum wire as above were immersed in this cooled solution for 1 minute at room temperature, and then dried in a chamber for 24 hours.

[Treatment Example 3] 0.5 g of γ-nyreidopropyltriethoxysilane and 0.5 g of nantimony dioxide were mixed with pure water heated to 80 to 98°C, and the same pure aluminum wire and 2% Si were added to the cooled solution. The compounded aluminum wire was immersed for 1 minute at room temperature and then dried in a chamber for 24 hours.

An X-ray microanalyzer and a Fourier transform infrared spectrometer (F
The aluminum surface deposits were analyzed using T-IR. Based on these results, in [Treatment Example 1], aminosilane and aluminum hydroxide were present on the surface of the aluminum wire;
It is presumed that aluminum hydroxide was present in Treatment Example 2, and deposits of St and sb other than aluminum hydroxide and aminosilane were present in Treatment Example 3.

[Examples 1 to 2] and [Comparative Examples 1 to 4] Molding materials were prepared by kneading the compositions shown in Table 1 for about 10 minutes using a mixing roll heated to about 80°C. Next, using a transfer molding machine, this molding material was molded into a disk of 10φ x 2tmm (180°C, 1.5 minutes). This disk was taken out from the mold and subjected to secondary curing at 180° C. for 5 hours in the atmosphere. Furthermore, this disk was crushed with a crusher to a particle size of 100.
It was made into a fine powder less than a mesh size.

Next, put 50g of pure water into a Teflon-lined SUS container.
5g of the above molding material powder and the above treatment example 3 as Example 1
A pure aluminum wire was placed in the SUs container, the SUs container was sealed, and the entire container was heated to 120°C.

The container was cooled at predetermined intervals and corrosion of the aluminum wire was observed. Aluminum laminate wire containing 2% silicon of treatment example 1 [
A similar test was also conducted for Example 2]. Similar tests were also conducted on untreated pure aluminum wires, aluminum wires containing 2% silicon, and treatment examples 1 to 2 [comparative examples 1 to 6].

The test results are shown in Table 2.

As is clear from Table 2, the surface of the aluminum wires of Comparative Examples 1 to 6 turned black after 48 to 72 hours, and
The wire broke during ~520 hours, whereas Examples 1 and 2
The aluminum wire did not change color or break even after 1440 hours.

[Examples 3 to 4] and [Comparative Examples 7 to 8] Semiconductor device wiring in which a zigzag wiring pattern of pure aluminum and 2% silicon-containing aluminum with a thickness of about 1 μm and a width of 10 μm was formed on a thermal oxide film of a silicon wafer. After the portion was treated in the above treatment example 3 [Examples 3 to 4], the semiconductor device was molded using the above molding material using a transfer molding machine.

Untreated products were also molded in the same manner [Comparative Examples 7 to 8].

The molding was carried out at 180°C for 1.5 minutes, then
Secondary curing was performed at 80°C for 5 hours. ′ [Example 5~
8] 0.5 g each of N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane (manufactured by Nihon Uniriki Co., Ltd., A-1120) and n-(dimethoxymethylsilylpropyl)ethylenediamine as aminosilane and carbon dioxide. Two types of treatment solutions were prepared by mixing 0.5 g of antimony with pure water heated to 80 to 98°C. Pure aluminum and silicon 2 of the same semiconductor device as above using each cooled processing solution.
After processing the zigzag wiring pattern portion of the aluminum compound, it was molded in the same manner as in Examples 3 and 4 above.

Next, each molded product was left in water vapor at 120° C. and 2 atm, and the time required for the aluminum wire to corrode and break was measured. The results are shown in Table 3.

As is clear from Table 3, the semiconductor devices of Examples 3 to 8, in which the aluminum wiring portion was treated with an aqueous solution containing aminosilane and diantimony dioxide, are the same as those of Comparative Examples 7 to 8, which were not treated.
Compared to No. 8, the time required for corrosion and disconnection of the aluminum wiring to occur is 2 to 8 times longer.

〔Effect of the invention〕

As is clear from the above description, in the resin-sealed semiconductor device of the present invention, corrosion of aluminum wiring is less likely to occur particularly under high temperature and high humidity conditions, and moisture resistance reliability can be dramatically improved.

Agent: Patent Attorney Akio Takahashi (゛ N Continuation of page 1 [Partner] Founder Kinjo Noriyuki Hitachi City Saiwai-cho 3 premises

Claims (1)

[Claims] 1. In a resin-sealed semiconductor device using aluminum and/or aluminum alloy as electrodes and wiring members, the surface of the aluminum and/or aluminum alloy as electrodes and wiring members is pre-coated in the process before sealing the semiconductor element with resin. A resin-sealed semiconductor device characterized in that it is treated with an aqueous solution containing antimony dioxide and an aminosilane compound and having a pH of 3 to 9.