JPH02297934A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent a high contact resistance between a bonding wire and an Al bonding pad by forming a polyimide film on a protective film, and etching a silicon nitride film or the like with the resin film patterned in a predetermined shape as a mask. CONSTITUTION:A protective film 12 such as a silicon nitride film, an oxide film, etc., is formed on a semiconductor device formed on the surface of a silicon board 11. Then, the film 12 is coated with liquidlike polyimide resin by a spinner, and baked to form a thermally cured polyimide resin 13. The resin 13 on an Al bonding pad 14 is patterned in a predetermined shape. With the resin 13 patterned in the predetermined shape as a mask the film 12 such as a silicon nitride film, an oxide film, etc., is dry checked. Thus, since the bonding pad is not brought into contact with the polyimide resin, a high contact resistance between the bonding wire and the pad can be prevented at the time of bonding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a method for manufacturing a protective film using polyimide resin.

[Conventional technology]

Conventionally, as a method of manufacturing a protective film for this type of semiconductor device, there is a method shown in FIGS. 2(a) to 2(d). As shown in FIG. 2(a), a protective film 2 such as a silicon nitride film or an oxide film is formed on a semiconductor device formed on the surface of a silicon substrate 1. Next, using the photoresist film as a mask, the protective film 3 on the aluminum bonding pad 3 is dry etched to obtain the result shown in FIG. 2(b). Next, polyimide resin 4 is applied using a spinner and cured by heat using a pre-vaporizer, as shown in Fig. 2 (C).
get.

Next, pattern the polyimide resin 4 into a predetermined shape,
Figure 2(d) is obtained.

[Problem to be solved by the invention]

In the conventional method for manufacturing a protective film for a semiconductor device as described above, after etching the protective film 2 on the aluminum bonding pad 3, a polyimide resin 4 is applied and heat-cured onto the aluminum bonding pad. There is a drawback that a reactant between polyimide and aluminum remains and the bonding wire and the aluminum pad have high contact resistance. The present invention provides a manufacturing method that does not generate a reaction product between aluminum and polyimide.

The manufacturing method of the present invention includes the steps of forming a protective film such as a silicon nitride film or an oxide film on a semiconductor device formed on the surface of a silicon substrate, and forming a polyimide resin film on the protective film to form a predetermined shape. The patterning process and the silicon nitride film using the patterned polyimide resin film as a mask.
It consists of a process of etching a protective film such as an oxide film.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

A protective film 12 such as a silicon nitride film or an oxide film is formed on the semiconductor device formed on the surface of a silicon substrate 11 as shown in FIG. 1(a). Next, a liquid polyimide resin is applied onto the protective film 12 using a spinner, and a heat-cured polyimide resin film 13 is formed by beta-coating, as shown in FIG.
). Next, the aluminum pounding pad 14
The polyimide resin 13 on top of the polyimide resin 13 is patterned into a predetermined shape to obtain the image shown in FIG. 1(C). Next, using the polyimide resin 13 patterned into a predetermined shape as a mask, the protective film 12 such as a silicon nitride film or an oxide film is dry-etched.
Figure (d) is obtained.

〔Effect of the invention〕

As explained above, the present invention involves forming a polyimide resin film on a protective film such as a silicon nitride film or an oxide film, patterning the polyimide resin film into a predetermined shape, and using the patterned polyimide resin film as a mask. By etching the silicon nitride film, oxide film, etc., the aluminum bonding pad and polyimide resin do not come into contact with each other, so no reaction product between aluminum and polyimide resin is generated on the bonding pad, making it easier to use with the bonding wire during bonding. This has the effect of preventing high contact resistance between aluminum bonding pads.

[Brief explanation of drawings]

1(a) to 1(d) are manufacturing process cross-sectional views of an embodiment of the method for manufacturing a protective film using polyimide resin for a semiconductor device of the present invention, and FIGS. 2(a) to 2(d) are respectively (d
) are process cross-sections showing a conventional method for manufacturing a protective film using polyimide resin for semiconductor devices. l, 11...Silicon substrate, 2.12...
・・Protective film such as silicon nitride film, oxide film, etc. 3, 14 ・・
...Aluminum pounding pad, 4.13
...Polyimide resin film. Agent Patent Attorney Uchihara Oto (a-9 (b) CC) (d) Figure l

Claims (1)

[Claims] A process of forming a protective film such as a silicon nitride film or an oxide film on a semiconductor device formed on the surface of a silicon substrate, a process of forming a polyimide resin on the protective film, and a process of patterning the polyimide resin into a predetermined shape. and a step of etching a protective film such as a silicon nitride film or an oxide film using a patterned polyimide resin as a mask.