JPH0327551A - Wiring structure of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a wiring structure with improved adhesion property by forming an inorganic insulating film on one part of the surface of a conductive film which is provided on a first organic insulating film, covering both the conductive film and the inorganic insulating film, and forming a second organic insulating film which is in contact with the first organic insulating film. CONSTITUTION:It is possible to achieve an improved adhesion between a conductive film 2 and a second organic insulating film 4 since an inorganic insulating film 3 exists between them. on the other hand. since a first organic insulating film 1 and the second organic insulating film 4 are in direct contact at an area other than the conductive film 2. it is possible to allow gas generated on heat treatment to be escaped readily. thus enhancing adhesion property between the first organic insulating film 1 and the second organic insulating film 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device, and particularly to a wiring structure using an organic insulating film as a glabellar insulating film.

[Conventional technology]

With the recent increase in the density of semiconductor devices, there is an increasing demand for flattening of the glabellar insulating film that insulates upper and lower wiring. Conventionally, inorganic films have been exclusively used as interlayer insulating films, but in order to meet the above-mentioned flattening requirements, it has recently been proposed to use organic insulating films.

For example, FIG. 5 shows an example of this, in which a first organic insulating film 41 is formed as an interlayer insulating film, a conductive film 42 is formed as a wiring on this, and a second organic insulating film 41 is formed as a cover insulating film on top of this. 2 organic insulating film 43 is formed.

Further, FIG. 6 shows another example in which a conductive film 52 is formed on the first organic insulating film 5l, the entire surface is covered with a thin inorganic insulating film 53, and then a second organic insulating film 54 is applied. ing. here,
The two-layer film of the inorganic insulating film 53 and the second organic insulating film 54 serves as a cover insulating film.

[Problem to be solved by the invention]

In the wiring structure shown in FIG. 5, since the conductive film 42 is directly covered with the second organic insulating film 43, the conductive film 42 and the second
The adhesion with the organic insulating film 43 is insufficient, and the second organic insulating film 43 is likely to peel off from this portion, resulting in a problem that the function as a cover is degraded and the reliability of the semiconductor device is degraded.

Further, in the wiring structure shown in FIG. 6, the conductive film 52 and the second
Since the inorganic insulating film 53 exists between the organic insulating films 54, the adhesion between the conductive film 52 and the second organic insulating film 54 is sufficient. However, since the inorganic insulating film 53 exists between the first organic insulating film 51 and the second organic insulating film 52, the gas generated in the first organic insulating film 51 when heat-treated at high temperature is released. ! (It is blocked by the organic insulating film 53 and cannot escape to the outside, which causes problems such as poor adhesion between the first organic insulating film 51 and the inorganic insulating film 53, and peeling of the cover insulating film.

The purpose of the present invention is to solve these problems, improve the adhesion between the wiring and the insulating film formed thereon, and also improve the adhesion between the insulating films formed above and below the wiring. The purpose is to provide a wiring structure.

[Means to solve the problem]

The wiring structure of the present invention has a conductive film constituting a wiring on a first organic insulating film constituting an interlayer insulating film, an inorganic insulating film in contact with the top and side surfaces of this conductive film, and these conductive films and a second organic insulating film that covers the inorganic insulating film and is in contact with the first organic insulating film.

In this case, the inorganic insulating film may be provided only on the upper surface of the conductive film, or may be provided only on the side surface of the conductive film.

[Effect]

In this configuration, the inorganic film provided on a part of the surface of the conductive film improves the adhesion between the conductive film and the second organic insulating film. Also,
The first organic insulating film and the second organic insulating film are in direct contact with each other in a region other than the conductive film to improve adhesion between the two.

〔Example〕

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

FIG. 1 is a sectional view showing the basic structure of the present invention, in which a conductive film 2 as a wiring is formed on a first organic insulating film 1 as an interlayer insulating film. An inorganic insulating film 3 is formed on the conductive film 2 so as to cover its upper and side surfaces, and then a second organic insulating film 4 is formed over the entire surface.

According to this configuration, since the inorganic insulating film 3 is interposed between the conductive film 2 and the second organic insulating film 4, excellent adhesion between the two can be achieved. On the other hand, since the first organic insulating film 1 and the second organic insulating film 4 are in direct contact with each other in areas other than the conductive film 2, gas generated during heat treatment can be quickly released, and the adhesion between the two can be improved. Improve. This prevents the second organic insulating film 4 as a Cacher film from peeling off and improves the reliability of the semiconductor device.

FIGS. 2(a) to 2(e) are cross-sectional views showing the first embodiment of the wiring structure shown in FIG. 1 in the order of manufacturing steps.

First, as shown in FIG. 2(a), a tungsten film 12 with a thickness of about 2,000 yen is deposited on a polyimide film 11 as a first organic insulating film constituting an interlayer insulating film by magnetron sputtering.
Then, a gold film 13 with a thickness of about 1 μm is formed to form a two-layer conductive film. Furthermore, a silicon nitride film 14 as an inorganic insulating film is deposited on this film by plasma CVD for approximately 20 minutes.
There is a 00 type.

Next, as shown in FIG. 2(b), the silicon nitride film 14, the gold film 13, and the tungsten film 12 are patterned by conventional photolithography to form wiring.

Next, as shown in FIG. 2(C), a silicon nitride film 15, which is an inorganic insulating film, is deposited on the entire surface by plasma CVD to a thickness of approximately 100%.
0 doll command.

Then, as shown in FIG. 2(d), anisotropic dry etching is performed on the silicon nitride film 15 in step 11;1.

As a result, the silicon nitride film 14 is left on the upper surface of the wiring, and the silicon nitride film 15 is left on the side surface, and the surface of the wiring is covered with these silicon nitride films 14 and 15.

In addition, as shown in FIG. 2(e), the second organic insulating film, which is a cover film, is made of solid ξdl]! J16 is formed on the entire surface by a spin-on coating method.

The structure of the wiring section obtained in this way has good adhesion between the gold film l3 and the silicon nitride film l4 constituting the wiring, and between the gold film l3 and the silicon nitride film l5, and the silicon nitride film l4 Since the adhesion between the polyimide film 16 and the silicon nitride film 15 and the polyimide film 16 is also good, the structure has excellent adhesion between the wiring and the cover film.

Moreover, since the polyimide film 11 and the polyimide film 16 are in direct contact with each other, the polyimide film 11 and the polyimide film 16 are in direct contact with each other, so that when heat treatment is performed at a high temperature, the polyimide film 11 and the polyimide film 16 are in direct contact with each other. Since the gas generated in 11 escapes through the polyimide film 16, the polyimide film 11 and polyimide 1 pattern 16
There is no deterioration in the density 71. That is, the structure is such that the adhesion between the interlayer insulating film and the cover insulating film does not deteriorate even when subjected to high-temperature heat treatment. Furthermore, since the tungsten film 12 exists between the gold film 13 and the polyimide film 1l, the structure has excellent adhesion between the wiring and the interlayer insulating film.

FIGS. 3(a) to 3(c) are cross-sectional views showing the second embodiment of the present invention in the order of manufacturing steps.

First, as shown in FIG. 3(a), an aluminum film 22 with a thickness of about 0.5 μm is formed by magnetron sputtering on the organic siloxane polymer film 2l constituting the interlayer insulating film, and an inorganic insulating film 22 is further formed by plasma CVD. There are about 2000 silicon oxide films 23.

Next, as shown in FIG. 3(b), the silicon oxide film 23 and the aluminum film 22 are patterned by ordinary photolithography to form wiring.

Thereafter, as shown in FIG. 3(c), a polyimide film 24 is formed as a cover film by spin-on coating.

The wiring structure obtained in this way consists of an argonium film 2
Since the silicon oxide film 23, which is an inorganic insulating film, is present on the upper surface of 2, the structure has excellent adhesion between the upper surface of the wiring and the cover film. Moreover, since the organic siloxane polymer film 21 and the polyimide film 24 are in direct contact with each other, the gas generated in the organic siloxane polymer film 21 when heat-treated at high temperature escapes through the polyimide film 24. The adhesion between the polymer film 2l and the polyimide film 24 does not deteriorate. That is, the adhesion between the interlayer insulating film and the cover insulating film is not deteriorated even by high-temperature heat treatment.

FIGS. 4(a) to 4(e) are cross-sectional views showing the third embodiment of the present invention in the order of manufacturing steps.

First, as shown in FIG. 4(a), about 1,000 titanium-tungsten alloy films 32 are deposited on the polyimide film 31 constituting the interlayer insulating film by magnetron sputtering, and then a gold film 33 is deposited with a thickness of approximately 0.5 μm. There is.

Next, as shown in FIG. 4(b), the gold film 33 and the titanium-tungsten alloy film 32 are patterned by the usual photolithography method to form wiring.

Next, as shown in FIG. 4(C), an oxygen-containing silicon nitride film 34, which is an inorganic insulating film, is formed on the entire surface by plasma CVD.
Approximately 2,000 dolls will be held.

Then, as shown in FIG. 4(d), anisotropic etching is performed on the oxygen-containing silicon nitride film 34 to form a polyimide If! The oxygen-containing silicon nitride film 34 present on the upper surface of the gold layer 31 and the gold layer 11i33 is removed. At this time, gold film 3
The side surfaces of 3 are covered with an oxygen-containing silicon nitride film 34.

Thereafter, as shown in FIG. 4(e), a polyimide film 35 is formed as a cover insulating film by spin-on coating.

The structure of the wiring section obtained in this way is such that the oxygen-containing silicon nitride film 34 as an inorganic insulating film is present on the side surface of the gold film 33 constituting the wiring, so that the adhesion between the side surface section of the wiring and the cover insulating film is high. It has an excellent structure. Moreover, since the polyimide film 31 and the polyimide film 35 are in direct contact with each other, the gas generated in the polyimide film 3I when heat-treated at high temperature escapes through the polyimide film 35. The adhesion between the polyimide film 35 and the polyimide film 35 does not deteriorate. That is, the adhesion between the interlayer insulating film and the Cacher insulating film is not deteriorated even by high-temperature heat treatment.

Furthermore, since the titanium-tungsten alloy film 32 is present between the gold film 33 and the bolioid ξ-do film 31, the structure has excellent adhesion between the wiring and the lower interlayer insulating film.

In each of the above examples, the first organic insulating film and the second organic insulating film are in contact with each other in all the regions where no conductive film is present, but the inorganic insulating film is present in some regions. However, the adhesion between both organic insulating films is not lost.

〔Effect of the invention〕

As explained above, the present invention forms an inorganic insulating film on a part of the surface of a conductive film provided on a first organic insulating film, and then a second organic insulating film.
Since the structure uses an organic insulating film, the adhesion between the conductive film and the second organic insulating film is improved by the inorganic film, and the adhesion between the first organic insulating film and the second organic insulating film is improved. ! Direct contact of the edge films improves the adhesion between the two, and as a result, a wiring structure with excellent adhesion can be obtained.

[Brief explanation of drawings]

Figure 1 is a sectional view showing the basic structure of the present invention, Figure 2 (a)
3(a) to 3(c) are sectional views showing the second embodiment of the present invention in the order of manufacturing steps, and FIG. a) to (e) are cross-sectional views showing the third embodiment of the present invention in the order of manufacturing steps, and FIGS. 5 and 6 are cross-sectional views showing different conventional wiring structures, respectively. DESCRIPTION OF SYMBOLS 1... First organic insulating film, 2... Conductive film, 3... Inorganic insulating film, 4... Second organic insulating film, 11... Polyide ξ film, l2... Tungsten film , 13... gold film,
l4... Silicon nitride film, l5... Silicon nitride film, 16... Polyimide film, 21... Organic siloxane polymer film, 22... Aluminum film, 23... Silicon oxide film, 24... ...Polyimide film, 31...Bollywood film, 32...Titanium-tungsten alloy film, 3
3... Gold film, 34... Oxygen-containing silicon nitride film, 3
5... Polyimide film, 41... First organic insulating film, 4
2... Conductive film, 43... Second organic insulating film, 51...
・First organic insulating film, 11 12 52... Conductive film, 53... Inorganic insulating film, 54...
Second organic insulating film. 13 Figure 3 Figure 5 Figure 6

Claims (1)

[Claims] 1. A conductive film constituting wiring is provided on a first organic insulating film constituting an interlayer insulating film, an inorganic insulating film is provided in contact with the top and side surfaces of this conductive film, and these conductive A wiring structure for a semiconductor device, comprising a second organic insulating film that covers the film and the inorganic insulating film and is in contact with the first organic insulating film. 2. having a conductive film constituting wiring on a first organic insulating film constituting an interlayer insulating film, having an inorganic insulating film in contact with the upper surface of the conductive film, covering these conductive films and the inorganic insulating film; A wiring structure for a semiconductor device, further comprising a second organic insulating film in contact with the first organic insulating film. 3. having a conductive film constituting a wiring on a first organic insulating film constituting an interlayer insulating film, having an inorganic insulating film in contact with the side surface of this conductive film, covering these conductive film and the inorganic insulating film; A wiring structure for a semiconductor device, further comprising a second organic insulating film in contact with the first organic insulating film.