JPH03159125A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent corrosion of a wiring and obtain a semiconductor device improved in moisture resistance by a method wherein a first and a second insulation films formed to cover a first and a second wiring layers respectively extend to the periphery of a semiconductor substrate while the second insulation film extends beyond the first insulation film. CONSTITUTION:In a semiconductor device composed of a semiconductor substrate 1 with impurities introduced to a desired position, a first wiring layer 3 formed on the substrate 1, a first insulation film 4 formed to cover the first wiring layer 3, a second wiring layer 5 formed on the first insulation film 4 and a second insulation film 6 formed on the second wiring layer 5, the first and second insulation films 4, 6 extend to the periphery of the semiconductor substrate 1 and the second insulation film 6 extends beyond the first insulation film 4. Thus even if the second insulation film peels off the semiconductor substrate at an end face of an semiconductor element, the first insulation film will not peel off thereby preventing moisture from entering. Therefore corrosion of the wiring layers can be prevented as well as a semiconductor device improved in moisture resistance can be obtained.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to the manufacture of semiconductor devices, and is applied to resin-filled semiconductor devices that use polyimide resin or the like as an insulating film or a final insulating film. It is about young technology.

[Conventional technology]

For general VCM fat-sealed semiconductor devices that are intended for wiring, especially those that use AL for the wiring layer and have two or more wiring layers, this is used to reduce the level difference in the wiring layer or to reduce costs. For this reason, some devices use polyimide resin or the like as an interlayer insulating film or final insulating film.

The structure of such a semiconductor device is to introduce impurities into a desired position of a semiconductor substrate, form a wiring layer such as AL on the upper surface, form an interlayer insulating film, and then perform wiring such as AL. The upper surface is covered with a final insulating film, after which dicing, pellet attachment, and bonding are performed, followed by resin sealing.

A known example is Japanese Patent Publication No. 57-22214 which shows a semiconductor device using polyimide resin as an insulating film.

[Problem to be solved by the invention]

However, the above technology does not take into account the relationship between the interlayer insulating film and the final insulating film, and the two insulating films overlap at the end face of the semiconductor element to form a contact surface. Common.

Therefore, when surface mounting is subjected to heat stress such as soldering during mounting or infrared reflow, a difference in thermal stress occurs between the sealing resin and the semiconductor element, and the end face of the semiconductor element is formed on the semiconductor substrate. Insulating films such as oxide films and insulating films made of polyimide resin, etc., peel off.
Moisture enters through the peeled part, and AL etc. are formed on the surface of the semiconductor substrate! There was a problem that it corroded the fa. Further, there is a problem in that the moisture resistance of the semiconductor device is reduced due to corrosion of the wiring such as the AL.

An object of the present invention is to provide a semiconductor device that prevents corrosion of the wiring and improves moisture resistance.

[Means to solve the problem]

The main points of typical inventions disclosed in this application are as follows.

That is, in the first means, a semiconductor substrate, a first wiring layer formed on the substrate, a first insulating film serving as an interlayer insulating film formed to cover the first wiring layer, and the In a semiconductor device having a second wiring formed on a first J8 edge film and a second insulating film which is a final insulating film formed on the second wiring layer, the first and second This is a semiconductor device in which the insulating film extends around the semiconductor substrate and a second insulating film is formed beyond the first insulating film.

In the second means, a semiconductor substrate, a wiring layer formed on the substrate, a groove provided around the substrate,
The semiconductor device has an insulating film covering the upper surface of the substrate.

[Effect]

According to the first means described above, the second
Even if the first insulating film and the semiconductor substrate peel off, the first insulating film will not peel off and moisture can be prevented from entering.
Corrosion of the wiring layer formed of L or the like can be prevented, and a semiconductor device with improved moisture resistance can be obtained.

According to the second method, on the end face of the semiconductor element, an insulating film is formed in the groove and the insulating film is filled in the groove to improve the adhesion between the semiconductor substrate and the insulating film, so that peeling due to thermal stress does not occur. It is possible to obtain a semiconductor device with improved moisture resistance, which can prevent the intrusion of moisture and prevent corrosion of wiring such as AL.

[Embodiment 1] FIG. 1 is a sectional view of a main part of a semiconductor device according to a first embodiment of the present invention, and FIG. 3 is a sectional view of a main part showing a method for manufacturing the semiconductor device shown in FIG. It is a diagram.

In FIG. 1 π, an oxide film 2 is formed on the upper surface of a semiconductor substrate 1 made of Sr or the like in which impurities or the like are introduced into desired positions and a diffusion layer or the like (not shown) is formed. The oxide film 2
A first wiring layer 3 made of AL is formed on the upper surface, a first insulating film 4 made of polyimide resin is formed on the upper surface thereof, and a second wiring layer 5 made of KAL is formed on the upper surface of the insulating film 4 and its upper surface. Similarly, there is a second layer made of polyimide resin, etc.
An insulating film 6 is formed to extend beyond the insulating film 4 and onto the oxide film 2 on the semiconductor substrate 1. Further, its surroundings are sealed with a sealing resin 7.

The manufacturing method of the present invention will be explained below with reference to FIG.

(&) Alt is deposited on the oxide film 2 on the upper surface of the semiconductor substrate l made of Si on which impurities are introduced into desired positions and diffusion layers etc. (not shown) are formed by a normal method, and then patterned. Then, the first wiring layer 3 is formed. (11
) In order to further form a second wiring layer on the first wiring layer, a first insulating film 4 made of polyimide resin is formed as a first layer.

(0) After this, similarly to the first wiring, the first insulating film 4 is
A second wiring layer 5 is formed by depositing AL on top and performing patterning. (d) After forming the second wiring, a second insulating film 6, which is a final insulating film made of polyimide resin or the like, similar to the insulating film 4, is formed on the upper surface. At the end face of this insulating film 6F1 that will become a semiconductor element, the insulation film 6F1
4, and further extends beyond the insulating film 4 to the periphery K of the oxide film on the semiconductor substrate 1. Thereafter, dicing is performed to separate each pellet, and after completing various steps such as pellet bonding, wire bonding, and resin sealing, a resin-sealed semiconductor device is obtained.

As described above, according to this embodiment, the positions of the insulating film between the wirings and the final insulating film on the end surfaces are adjusted, the second insulating film is extended to enclose the first insulating film, and the second insulating film is extended to enclose the first insulating film. By preventing peeling, a semiconductor device with improved moisture resistance can be obtained.

[Embodiment 2] FIG. 2 is a cross-sectional view of important parts showing a second example of the semiconductor device of the present invention, and FIG. 4 is a cross-sectional view of important parts showing a manufacturing method thereof.

In FIG. 2, the periphery 1t# of the semiconductor substrate 8 in which impurities and the like are introduced into desired positions and diffusion layers and the like (not shown) are formed.
xo is formed. An oxide film 9 is formed on the semiconductor substrate 8, and a first wiring layer 11 made of AL or the like is formed on the upper surface of the oxide film 9.
Further, a first insulating film 12 which is an interlayer insulating film made of polyimide resin or the like is formed on the upper surface thereof, a second wiring layer 13 made of AL is formed on the insulating film 12, and a second wiring layer 13 made of AL or the like is formed on the upper surface thereof. A second insulating film 14, which is the final insulating film, is formed so as to reach the groove 10 formed in the semiconductor substrate IK, and its periphery is sealed with a sealing resin 14.

The explanation will be given below with reference to FIG.

(&) AL is deposited on an oxide film 9 formed on a semiconductor substrate 8 made of SL into which impurities and the like are introduced and a diffusion layer (not shown) has been formed using a normal method, and patterned into a desired shape. Then, the first wiring layer 11 is formed. (b) A first insulating film 12 made of polyimide resin or the like is formed to cover the first wiring layer 11. (0) A second wiring layer 13 is deposited on the first strict film 12 by AL vapor deposition, and patterned to form a second wiring layer 13 in the same manner as the first wiring layer 11.
form. (<1) Next, a groove 10 is formed around the semiconductor substrate 8, which is to become a semiconductor pellet, by etching. (・) Then, on the wiring layer 13 of the tube 2, an insulating film 14 made of polyimide resin is extended to the groove 10K.
The resin of the second insulating film 14 is formed so as to fill the tc and s grooves 10. At this time, the distance θ that the second insulating film 14 extends beyond the first insulating film 12 is Fi30 μm.
depth θ in direction 10.

It was effective to form the width a and the width a to be about 20 μm.

After this, dicing is performed to separate each pellet. Further pellet attachment and wire bonding.

A semiconductor device is obtained through various steps such as resin encapsulation.

According to this embodiment, since the adhesiveness between the final insulating film and the semiconductor substrate can be improved by forming the fa around the semiconductor device, it is possible to obtain a semiconductor device with the same moisture resistance.

As described above, in the present invention, the polyimide resin, which is the background of the present invention, is used as an insulating film. Although the semiconductor device with the AL two-layer wiring has been described, it goes without saying that the present invention is not limited to the above embodiments and can be modified in various ways.

For example, a single-layer AL wiring can be used, and it is also possible to use a material other than polyimide resin as an insulating film.

〔Effect of the invention〕

A brief explanation of the effects obtained by the typical methods disclosed in the present invention is as follows.

That is, by slightly changing the structure of the insulating film formed on the semiconductor substrate of the semiconductor device and the semiconductor substrate, a semiconductor device t' with improved moisture resistance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the main parts of a semiconductor device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the main parts of the backing device for the semiconductor device shown in FIG. FIG. 4 is a cross-sectional view of main parts showing a method for manufacturing a semiconductor device according to a second embodiment of the present invention shown in FIG. 1.8...Semiconductor substrate, 2.9...Oxide film, 3.1
1... Wiring layer (first), 4.12... Insulating film (first
), 5.13... Wiring layer (second), 6.14... Final insulating film (second), 7, 15... Sealing resin s 10.
・・Groove diagram (0) /6 Figure 4 (0) (b) Figure

Claims (1)

[Claims] 1. A semiconductor substrate into which impurities are introduced at desired positions, a first wiring layer formed on the substrate, and a first wiring layer formed to cover the first wiring layer. a second wiring layer formed on the first insulation film; and a second insulation film formed on the second wiring layer; A semiconductor device characterized in that the second insulating film extends around the semiconductor substrate, and the second insulating film is formed beyond the first insulating film. 2. It is characterized by comprising a semiconductor substrate into which impurities are introduced at desired positions, a wiring layer formed on the substrate, a groove provided around the substrate, and an insulating film covering the upper surface of the substrate. semiconductor devices. 3. The semiconductor device according to claims 1 and 2, wherein the insulating film is made of polyimide resin.