JPH01298740A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent a wiring layer pattern from being affected by etching residue produced when forming said wiring layer pattern, by adhering an insulating film in the same pattern above the wiring layer pattern. CONSTITUTION:After forming an SiO2 film 2 on a silicon substrate 1 by oxidation, an Al wiring film 13 is formed by deposition and an insulating film 15 of SiO2 is formed by CVD method. Etching the films 13 and 15 with an appropriate mask to form an Al wiring layer pattern forms a semiconductor device having an Al wiring layer pattern 3 and an SiO2 film 5 accumulated thereon. This prevents etching residue, even it produced, from reaching the wiring layer pattern and the pattern from short-circuiting.

Description

[Detailed Description of the Invention] [Summary] Regarding a conductor device having a wiring layer pattern made of a conductive material, an object of the present invention is to eliminate the adverse effect on the wiring layer pattern caused by etching residue generated during formation of the wiring layer pattern. For this purpose, the wiring layer pattern is configured to have an insulating film deposited above it in the same pattern.

[Industrial application field]

The present invention relates to a semiconductor device, and more specifically, to a semiconductor device having a wiring layer pattern made of a conductive material. In the semiconductor device according to the present invention, short circuits in wiring layer patterns can be eliminated and device malfunctions can be reduced.

[Conventional technology]

In a semiconductor device, a wiring layer pattern is formed by forming a film of a conductive material such as aluminum on the entire surface of an insulating film such as a Si film (12), and then etching this conductive film (12). A conventional example is explained with reference to Fig. 4.First, Fig. 4 (A
), a silicon oxide film (SiO□ film) 2 is formed on a silicon substrate 1 by oxidizing the silicon, and an aluminum wiring film 13 is further formed above it by, for example, vapor deposition. Subsequently, the formed aluminum wiring film 13 is etched according to a desired wiring layer pattern. As shown in FIG. 4(B), a semiconductor device having a wiring layer pattern 3 made of aluminum is obtained.

By the way, in the conventional semiconductor device, the above-mentioned figure 4 (
As shown in B), the edges of the wiring layer pattern 3 are often exposed, and the side walls of the exposed edges of the pattern have etching residues made of the same material as the wiring layer pattern (in the example shown, reference number 4) is often left behind.

Such etching residues may be scattered during subsequent processing and adhere to patterns in device areas. As can be well understood, if the scattered etching residue adheres to the pattern in the device area, it will cause short circuits and malfunction of the device. Although it is desirable to remove the etching residue attached to the pattern in the device area, this is practically difficult, so if possible,
It is desirable to eliminate the adverse effects on the wiring layer pattern caused by deposited etching residue.

[Problem to be solved by the invention]

Therefore, an object of the present invention is to eliminate, in a semiconductor device having a wiring layer pattern made of a conductive material, an adverse effect on the wiring layer pattern caused by etching residue generated during formation of the wiring layer pattern.

[Means to solve the problem]

According to the present invention, the above object can be achieved by a semiconductor device characterized in that a wiring layer pattern has an insulating film deposited in the same pattern above the wiring layer pattern.

The above-mentioned object is also achieved according to the present invention by a semiconductor device as described above, characterized in that the wiring layer pattern further has an insulating film deposited on the side surface thereof. can do.

In the present invention, when forming a wiring layer pattern of a device, a conductive film for forming a wiring layer pattern and an insulating film are sequentially formed, and then patterning is performed to form a wiring layer pattern. Since there is an insulating film deposited on the wiring layer pattern, even if etching residue is generated as a result of patterning,
The adverse effects of the etching residue do not extend to the wiring layer pattern of the device. Furthermore, in order to further enhance this effect, it is recommended to apply an insulating film to the side surfaces of the wiring layer pattern.

Furthermore, according to the present invention, the above-mentioned object is such that the wiring layer pattern has an insulating film deposited on the entire surface thereof, and the wiring layer pattern is identical to the pattern generated when forming the wiring layer pattern. This can be achieved by a semiconductor device characterized in that when there is an etching residue made of a material, the etching residue is changed into an insulating material.

In the present invention, when forming a wiring layer pattern for a device, an insulating film is applied to the entire surface of the wiring layer pattern after the wiring layer pattern is formed, and if there are any etching residues, they are converted into an insulator.

For example, if the wiring layer pattern is made of aluminum, this can be advantageously carried out by oxidizing it to form a thin film of alumina (and an etching residue made of alumina).

The etching residue, which has become an insulator, will no longer have an adverse effect on the formed wiring layer pattern.

In the implementation of the present invention, the wiring layer pattern can be made of conductive wiring materials commonly used in this technical field, such as aluminum alloy, gold, silicide, polysilicon, etc., in addition to the above-mentioned aluminum. . In addition, the insulating film is, for example, an Al2O2 film, a Si
It can be an n□ film, a PSG film, or the like. It takes forever ♀
For example, if the wiring layer pattern is made of aluminum, the formation of the oxidized film can be advantageously carried out by immersing the wiring layer pattern in hot water to oxidize it, or by treating it with concentrated nitric acid. can.

[For production]

In the present invention, since the insulating film is left on the conductive film, even if etching residue is generated during the formation of the wiring layer pattern of the device, the adverse effects of the etching residue will not extend to the wiring layer pattern. do not have. Furthermore, in the present invention, even if etching residue is generated during the formation of the wiring layer pattern of a device, the etching residue is converted into an insulator. It never reaches.

〔Example〕

FIG. 1 shows a semiconductor device according to the present invention and its manufacturing process in order. First, as shown in FIG.
After forming by oxidation, an aluminum wiring film 13 is formed by vapor deposition to a thickness of about 1-. Subsequently, as shown in FIG. 1(B), an insulating film 15 of 5i
n2 is formed to a thickness of about 100 mm by CVD.

Thereafter, when the films 13 and 15 are etched using a suitable mask (not shown) to form an aluminum wiring layer pattern, the aluminum wiring layer patterns 3 and 15 are etched as shown in FIG. A semiconductor device having the Sin film and the film 5 in this order is obtained. Although not shown in the drawings, even if etching residue occurs, for example as shown in FIG. 4(B), the etching residue will not reach the wiring layer pattern, thus preventing short circuits in the pattern. be able to.

Further, in addition to the 5102 film 5 as shown in FIG. 1(C), the semiconductor device of the present invention has the following features as shown in FIG.
The side surface of the aluminum wiring layer pattern 3 may also have a Sin□l cutout 6. Additional 8102 membrane 6 like this
This is very useful when it is assumed that one end of the etching residue is cut off for some reason and comes into contact with the wiring layer pattern. Such a 5in2 film 6 can be advantageously formed, for example, by immersing the substrate after buttering in hot water and wet oxidizing it at about 90°C for several tens of seconds. 5) and (B) sequentially show preferred manufacturing processes for another semiconductor device according to the present invention. In the illustrated example, as shown in FIG. 3(A),
On the edge part of the aluminum wiring layer pattern 3 formed on one side of the SiO film 2 of the silicon substrate 1-L, etching residue (aluminum, karanaro) 4 generated during formation of the wiring layer pattern forms a bridge. It's listed. Konoma 5
If the process continues, the etching residue will scatter and cause small particles such as 12, smudges, etc. to run parallel to the pattern in the device area.

In the present invention, the silicon substrate having the etching residue 1 on the wiring layer pattern 3 is subsequently immersed in warm water at about 90 DEG C. for several 10 seconds to several minutes. Then, as a result of this wet oxidation, aluminum is changed to alumina, and specifically, as shown in FIG.
At the same time, the surface of the wiring layer pattern 3 is coated with a thickness of several tens to hundreds of layers (in some cases, several thousand layers).
An insulating film 17 consisting of S l (12) is formed. Here, the etching residue is converted into an insulator piece, so even if it hits the wiring layer pattern, there will be no inconvenience. Not woken up.

〔Effect of the invention〕

According to the present invention, it is possible to prevent short circuits in the wiring layer pattern of a device caused by etching residues that are difficult to remove, thereby reducing the reliability and yield of the device. It turns blue.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a semiconductor device according to the present invention and its manufacturing process in order; FIG. 2 is a cross-sectional view showing a modification of the semiconductor device of FIG. 1; FIG. FIG. 4 is a cross-sectional view sequentially showing another semiconductor device according to the invention and its manufacturing process, and FIG. 4 is a cross-sectional view sequentially showing a conventional semiconductor device and its manufacturing process. In the figure, 1 is a silicon substrate, 2 is a 5102 film, 3 is an aluminum wiring layer pattern, and 5 is a SiO□ film.

Claims (1)

[Scope of Claims] 1. A semiconductor device characterized in that a wiring layer pattern has an insulating film deposited in the same pattern above the wiring layer pattern. 2. The semiconductor device according to claim 1, wherein the wiring layer pattern further has an insulating film deposited on a side surface thereof. 3. If the wiring layer pattern has an insulating film deposited on its entire surface and there is an etching residue made of the same material as the pattern generated during the formation of the wiring layer pattern, the etching A semiconductor device characterized in that the remainder is changed into an insulating material.