JPS6112044A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain an insulating layer having entirely no pinholes by a method wherein an insulating film of two-layer structure consisting of organic and inorganic substance is formed. CONSTITUTION:Under the state wherein a regular aperture part 30 formed by performing a patterning on a negative type resist film 24, a pinhole 31 formed on the contaminated part of a mask, a pinhole 28 on a negative type resist film, and the intrinsic pinhole 23 present on a silicon dioxide fiom are formed, a positive type resist film 33 is coated thereon, and a patterning is performed using a positive type mask 34. A regular pattern 35 and a cut-away part 36 are supposed to be present on the above-mentioned mask 34. In this case, only an aperture part 37 formed by regular pattern is formed on a silicon dioxide film 32, no pinholes are formed by the help of the pinholes 28 and 33 of the negative type resist film, the effect of the cut-away part 26 of the positive type resist film has no direct relation with the negative type resist film 24, and the second wiring 38 is performed as above-mentioned.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a method for manufacturing an insulating layer between the eyebrows, and more particularly to a method for manufacturing an insulating layer of a cross wiring portion in a semiconductor device.

(Middle) Technical background In recent years, as semiconductor devices have become more highly integrated and insulation layers have become higher in voltage, there has been a rise in voltage resistance failures due to pinholes in insulation layers in the area between the eyebrows, and improvements to these problems have been desired.

(C) Conventional technology and problems.

Conventionally, there are two methods for interlayer insulating layers: one is to use inorganic materials such as silicon dioxide (Si02) and aluminum oxide (^120 +1), and the other is to use organic resins. membrane is used.

Generally, pinholes that occur in the insulating layer cause dielectric breakdown between the eyebrows and cause short circuits, but the first reason why pinholes with a diameter of 1 μm or less occur is
In some cases, the cause is due to the manufacturing process during film formation, and in the second case, the cause is in the patterning process.

If the cause is due to patterning, mask contamination is a problem for negative resist films, and defects in the mask pattern are common for positive resist films.

Figure 1 explains the principle of patterning and pinholes when using a negative resist film.
In Figure 1 (1), 1 is the substrate, 2 is the first wiring layer, 3 is the negative resist film, 4 is the mask, 5 is the regular pattern on the mask, 6 is the contaminated part of the mask, and the arrow is the ultraviolet rays. It is.

When this negative resist film is irradiated with ultraviolet rays, the exposed parts of the resist film remain as they are and become an insulating film, as shown in FIG. The portion 6 blocks ultraviolet rays so that the resist film is not exposed to light and is removed by etching, forming a regular opening 7 and a pinhole 8.

Normally, a negative resist film is patterned and used as an insulating film, so when a second wiring layer is formed on top of this, pinholes 8 can cause short circuits between the wirings. becomes.

Figure 2 (11 is a case where a positive resist film is used, 11 is a substrate, 12 is a first wiring layer, but generally a positive resist film has low heat resistance and is not used as an insulating film. Therefore, an inorganic insulating layer is required, so there is an inorganic silicon dioxide I'll! 13, 14 is a positive resist film, 15 is a mask, 16 is a regular pattern on the mask, and 17 is a missing mask. Part 1B indicates the original pinhole existing in the silicon oxide film, and the arrow indicates ultraviolet rays.

FIG. 2 (2) shows a patterned pattern using a positive resist film. In addition to the opening 19 in the silicon dioxide film 13, the original pinhole 18 and the missing part of the patterning of the mask are exposed. Pinholes 20 are formed, which also cause short circuits when the second wiring layer is formed.

As described above, it was necessary to strictly control dustproofing and handling to prevent contamination of the butter coating on the mask and to prevent pinholes from forming in the resist film and silicon dioxide film.

(d) Object of the Invention In view of the above-mentioned conventional drawbacks, an object of the present invention is to provide a method for manufacturing an insulating layer without pinholes by using two types of layers as the insulating layer.

According to the present invention, an inorganic insulating layer is formed on a substrate on which a first wiring layer is formed, a resist film is formed on the inorganic insulating layer, and then the resist film is formed on the inorganic insulating layer. An opening is provided that penetrates the film and the insulating layer of the inorganic material, and a second resist film is formed on the resist film while leaving the resist film in the area other than the opening.
This can be achieved by providing a method for manufacturing a semiconductor device characterized by forming a wiring layer.

(f) Embodiments of the Invention In general, the dielectric strength required for an insulating film is IMΩ or higher, but it is particularly suitable for devices that require high reliability or dense patterns manufactured by advanced design. Therefore, it is necessary to sufficiently guarantee dielectric strength between the eyebrows, and for this purpose, by forming a two-layer insulating film with an inorganic layer as the lower insulating film and an organic material layer as the upper layer, short circuits caused by pinholes can be prevented. It eliminates the phenomenon.

That is, when a negative resist film is applied to a silicon dioxide film as an organic insulating material and patterned by exposure using a mask, the negative resist film has 1. The pinholes due to contamination of the mask and the original pinholes in the silicon dioxide film are patterned, but this is then exposed using a positive resist so that the openings are in a regular pattern, developed, and the positive resist is formed. The silicon oxide film is patterned by opening the film, and the pinholes formed between the positive and negative resist films compensate for each other and prevent short circuits caused by the pinholes.

On the other hand, when using a positive resist film first, pattern the underlying silicon dioxide film with the positive resist, then remove this positive resist and apply a new negative resist film. By performing predetermined patterning, it is possible to prevent pinholes from connecting to each other.

In this way, all pinholes generated during the process compensate each other in the two layers to form a complete insulating layer.

FIG. 3(1) shows an embodiment of the present invention, in which 21 is a substrate, 2
2 is a first wiring part, 23 is a silicon dioxide film, 24 is a negative resist film, 25 is a mask, 26 is a regular mask pattern, 27 is a contaminated part on the mask, 28 is a pinhole in the negative resist film, 29 is the original pinhole that exists in the silicon dioxide film.

FIG. 3(2) shows that the negative resist film 24 is patterned to form a regular opening 30, a pinhole 31 formed by a contaminated part of the mask, and a pinhole 2B in the negative resist film.
and the original pinhole 23 that exists in the silicon dioxide film.
With the above formed, a positive type resist 33 is further applied and patterned with a positive type mask 34, but it is assumed that this mask has a regular pattern 35 and a missing part 36. .

As shown in FIG. 3(3), only openings 37 formed in a regular pattern are formed in the silicon dioxide film 23.
Because of the pinholes 28 and 33 in the negative resist film, no pinholes are formed in the silicon oxide, and the effect of the missing portion 26 in the positive resist film is not directly related to the negative resist film 24. Then, the second wiring 38 is formed.

FIG. 4 (1) is an example in which a positive type resist film is used, and 641 is a substrate, 42 is a first wiring part, 43 is a silicon dioxide film, 44 is a positive resist film, and 45 is a Mask, 46 is regular pattern part, 47 is missing part, 48
is a pinhole that existed in the silicon dioxide film.

Figure 4 (2) shows that pinholes 48 are formed by patterning.
Then, a pinhole 49 and a regular opening 50 are formed due to the missing part of the mask, but after this, a positive resist film 4 is formed.
4 is removed, a new negative resist film 51 is applied, and irradiation is performed using a mask 52.

FIG. 4(3) shows a negative type cyst film patterned and opened in this way.
pinholes 56 due to mask contamination 54
However, there is no connection with pinholes in the silicon dioxide film, so there is no risk of short-circuiting.

(Effects of the Invention As explained in detail above, by forming the insulating film with the organic and inorganic two-layer structure of the present invention, an insulating layer completely free of pinholes can be created, which improves the reliability of semiconductor devices. There is a great effect that it can be used for.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views illustrating a conventional wiring layer manufacturing method, and FIGS. 3 and 4 are sectional views illustrating a wiring layer manufacturing method according to the present invention. In the figure, 21 is a substrate, 22 is a first wiring part, 23 is a silicon dioxide film, 24 is a negative resist film, 25 is a mask, 26 is a regular mask pattern, 27 is a contaminated part on the mask, and 28 is a negative resist film. A pinhole in the resist film, 29 is a pinhole in the silicon dioxide film, and 38 is a second wiring.

Claims (3)

[Claims] (1) After forming an inorganic insulating layer on the substrate on which the first wiring layer is formed and forming a resist film on the inorganic insulating layer, the resist film and the inorganic insulating layer are penetrated. 1. A method of manufacturing a semiconductor device, comprising providing an opening and forming a second wiring layer on the resist film while leaving the resist film in a portion other than the opening. (2) The step of forming the resist film consists of forming a negative resist film, patterning the negative resist film with a predetermined opening pattern, and then depositing a positive resist film thereon. After forming the opening in the inorganic insulating layer portion by patterning in a pattern corresponding to the resist film, the upper positive resist film is removed and the second wiring is formed while leaving the lower negative resist film. 2. A method of manufacturing a semiconductor device according to claim 1, further comprising: forming a semiconductor device. (3) In the step of forming the resist film, after forming a positive resist film and patterning the positive resist film with a predetermined opening pattern, the insulating layer of the inorganic material is opened and patterned, and then The positive resist film is removed, a negative resist film is deposited on the inorganic insulating layer portion, and a predetermined patterning is performed, and then a second wiring is formed on the negative resist film. A method for manufacturing a semiconductor device according to claim 1.