Semiconductor device manufacturing: process – Coating of substrate containing semiconductor region or of...
Reexamination Certificate
2001-07-16
2002-07-16
Nelms, David (Department: 2818)
Semiconductor device manufacturing: process
Coating of substrate containing semiconductor region or of...
C438S782000
Reexamination Certificate
active
06420276
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor device and a semiconductor device manufacturing method and, more particularly, a semiconductor device and a semiconductor device manufacturing method for forming an interlayer insulating film containing a coating insulating film having a low dielectric constant.
2. Description of the Prior Art
In recent years, the multi-layered wiring structure using the interlayer insulating film having the low dielectric constant is employed with the higher integration degree and the higher density of the semiconductor integrated circuit devices. In such case, the coating insulating film that is excellent in flatness and has the low relative dielectric constant is often employed as the interlayer insulating film.
The coating insulating film having the low relative dielectric constant can be obtained by coating the coating liquid containing the silicon-containing inorganic compound or the coating liquid containing the silicon-containing organic compound. on the film forming surface by the spin coating method and then removing the solvent in the coating liquid by the heating.
However, the coating insulating film contains a large amount of moisture in the film and has the high hygroscopicity. Also, the strength of the coating insulating film itself is relatively low. Since the coating insulating film has a poor adhesiveness with a CVD (Chemical Vapor Deposition) film or a metal wiring layer, there is a fear of resulting in peeling-off of the film.
In order to compensate the weak point of the coating insulating film, such a structure is often employed that a cap layer (upper protection layer) and a liner layer (lower protection layer) containing Si and N or Si and C are formed on and under the coating insulating film to wrap the coating insulating film therein.
The semiconductor device having a multi-layered wiring comprises an interlayer insulating film that is formed between the upper and lower wirings by laminating in order the lower protection layer containing Si and N or Si and C, the coating insulating film and the upper protection layer containing Si and N or Si and C.
However, since the insulating film containing Si and N has a high relative dielectric constant, the entire interlayer insulating film results in having a higher dielectric constant even if employing the lower and upper protection layers of thinner thickness.
It is difficult for the lower and upper protection layers containing Si and C to sufficiently suppress an increase of a leakage current while the lower and upper protection layers containing Si and C have lower relative dielectric constants than the lower and upper protection layers containing Si and N.
In addition, it is impossible to say that the adhesiveness between the coating insulating film and the lower and upper protection layers containing Si and N or Si and C is good, and thus the barrier characteristic to the moisture, etc. is not perfect.
On the other hand, there is an occasion where the other lower and upper protection layers are formed on the lower and upper surfaces of the coating insulating film using a plasma enhanced chemical vapor deposition method (hereinafter, referred to as PE-CVD method). PE-CVD method is capable of film-forming at a relatively lower range of temperature while using a gas containing SiH
4
and N
2
O, a gas containing SiH
4
and O
2
, or a gas containing TEOS and O
2
as a film-forming gas in order to improve the adhesiveness.
However, in the other lower and upper protection layers, there are problems as follows for the reasons why the adhesiveness to the coating insulating film and a mechanical strength of the film itself is not sufficient, and a gas having a strong oxidizing reaction is employed.
(i) There arises the peeling-off of the coating insulating film at an interface between the coating insulating film and the lower or upper protection layer.
(ii) The laminated structure in the semiconductor device is destroyed through the destroy of the lower protection layer as a stopper which serves as a framework (for reinforcement) during processing, especially CMP (Chemical mechanical Polishing).
(iii) At a formation of the upper protection layer, the usage of the film-forming gas including the gas having the strong oxidizing reaction results in an increase of the dielectric constant due to an oxidization of the coating insulating film.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a semiconductor device and a semiconductor device manufacturing method, in a cover insulating film constituted by a coating insulating film and a protection layer for covering an upper surface or a lower surface of the coating insulating film, or in an interlayer insulating film constituted by a coating insulating film and a protection layer for covering an upper surface and a lower surface of the coating insulating film, capable of forming the cover insulating film or the interlayer insulating film that can achieve a lower dielectric constant as a whole, has a more complete barrier characteristic to the moisture, or the leakage current, etc., and is excellent in flatness.
It is another object of the present invention to provide a semiconductor device and a semiconductor device manufacturing method capable of improving an adhesiveness between the protection layer and the coating insulating film and a mechanical strength of the protection layer itself.
Advantages that are achieved by a configuration of the present invention will be explained as follows.
In the present invention, a protection layer is formed to cover a coating insulating film by plasmanizing a first film forming gas to react, wherein the first film forming gas consists of any one selected from a group consisting of alkoxy compound having Si—H bonds and siloxane having Si—H bonds and any one oxygen-containing gas selected from a group consisting of O
2
, N
2
O, NO
2
, CO, CO
2
, and H
2
O.
According to the experiment made by the inventors of the present invention, it is found that the silicon-containing insulating film formed by plasmanizing the first film forming gas to react has a good adhesiveness to the coating insulating film, is dense to the same extent as the silicon nitride film, is excellent in the water resistance, and contains the small content of moisture in the film.
In this manner, the plasma CVD insulating film according to the present invention has the good adhesiveness to the coating insulating film and also has the density equivalent to the silicon nitride film. Therefore, when the plasma CVD insulating film according to the present invention is formed to come into contact with the coating insulating film and to cover the coating insulating film like the configuration of the present invention, there can be obtained the cover insulating film that can have the more complete barrier characteristic to the entering of the moisture into the coating insulating film from the outside and to the flowing-out of the moisture to the outside, while being excellent in flatness.
Also, the plasma CVD insulating film according to the present invention has the lower relative dielectric constant than the silicon nitride film in addition to the above characteristics. The protection layer made of the plasma CVD insulating film according to the present invention are formed on at least any one of an upper surface and a lower surface of the coating insulating film which serves as the main cover insulating film or the main interlayer insulating film and has the low relative dielectric constant. There can be obtained the cover insulating film or interlayer insulating film that has more completely the barrier characteristic to the entering/flowing-out of the moisture into/from the coating insulating film, the barrier characteristic to the leakage current, etc. and also achieves the low dielectric constant as a whole.
In this manner, according to the present invention, there can be obtained the cover insulating film or interlayer insulating film that can achieve the low
Aoki Junichi
Koromokawa Takashi
Maeda Kazuo
Oku Taizo
Yamamoto Youichi
Canon Sales Co., Inc.
Lorusso & Loud
Nhu David
LandOfFree
Semiconductor device and semiconductor device manufacturing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Semiconductor device and semiconductor device manufacturing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor device and semiconductor device manufacturing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2823847