US4903117A
Expired / Lapsed
US
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Semiconductor device
Assignee: Mitsubishi Electric Corp
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Filing: 1988-06-07
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Granted: 1990-02-20
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Expires: 2008-06-07
Abstract
Abstract A silicon oxide film and a BPSG film are formed on a silicon substrate to serve as insulating films, and a contact hole is selectively formed in the insulating films. An impurity diffusion layer is formed on the surface layer of the semiconductor substrate at the bottom portion of the contact hole. A second metal film serving as a metal electrode is formed to cover the BPSG film and the impurity diffusion layer, and a first metal film serving as a barrier layer is formed between the second metal film and the BPSG film and impurity diffusion layer. The first metal film prevents boron contained in the BPSG film from being diffused in the second metal film, thereby to prevent precipitation of silicon in the contact hole.
Inventors
- 👤 Tatsuo Okamoto
- 👤 Ikuo Ogoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:19
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/41; H10W20/425; Y; Y10; Y10S; Y10S257/00; Y10S257/915
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
141 words
A semiconductor device comprising: a silicon substrate; a first silicon oxide film formed on the surface of said silicon substrate; a second silicon oxide film formed on said first silicon oxide film and containing boron and phosphorus; a contact hole selectively formed in said first and second silicon oxide films; an impurity diffusion layer formed on the surface layer of said silicon substrate at the bottom portion of said contact hole; a first metal film formed on said second silicon oxide film and said impurity diffusion layer to serve as a barrier layer; and a second metal film of aluminum alloy containing silicon formed on said first metal film to serve as a metal electrode; said first metal film comprising a material capable of preventing boron contained in said second silicon oxide film from being diffused into said second metal film.
Claim 2
Dependent Claim
141 words
A semiconductor device comprising: a silicon substrate; a first silicon oxide film formed on the surface of said silicon substrate; a second silicon oxide film formed on said first silicon oxide film and containing boron and phosphorus; a contact hole selectively formed in said first and second silicon oxide films; an impurity diffusion layer formed on the surface layer of said silicon substrate at the bottom portion of said contact hole; a first metal film formed on said second silicon oxide film and said impurity diffusion layer to serve as a barrier layer; and a second metal film of aluminum alloy containing silicon formed on said first metal film to serve as a metal electrode; said first metal film comprising a material capable of preventing boron contained in said second silicon oxide film from being diffused into said second metal film.
Claim 3
Dependent Claim
20 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of titanium nitride (TiN).
Claim 4
Dependent Claim
20 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of titanium-tungsten alloy (TiW).
Claim 5
Dependent Claim
19 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of tungsten (W).
Claim 6
Dependent Claim
20 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of tantalum nitride (TaN).
Claim 7
Dependent Claim
22 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of molybdenum silicide (MoSi 2 ).
Claim 8
Dependent Claim
22 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of tungsten silicide (WSi 2 ).
Claim 9
Dependent Claim
22 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of titanium silicide (TiSi 2 ).
Claim 10
Dependent Claim
22 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a film of tantalum silicide (TaSi 2 ).
Claim 11
Dependent Claim
17 words
A semiconductor device in accordance with claim 1, wherein said first metal film is a polysilicon film.
Claim 12
Dependent Claim
22 words
A semiconductor device in accordance with claim 1, wherein: said second silicon oxide film contains at least one percent by weight boron.
Claim 13
Dependent Claim
164 words
A semiconductor device comprising: a silicon substrate; a first silicon oxide film formed on the surface of said silicon substrate; a second silicon oxide film formed on said first silicon oxide film and containing boron and phosphorus; a contact hole selectively formed in said first and second silicon oxide films; an impurity diffusion layer formed on the surface layer of said silicon substrate at the bottom portion of said contact hole; a first metal film formed on said silicon oxide film and said impurity diffusion layer to serve as a barrier layer; and a second metal film of aluminum alloy containing silicon formed on said first metal film to serve as a metal electrode; said first metal film being formed of a material which prevents boron contained in said second silicon oxide film form being diffused into said second metal film and which prevents precipitation of silicon in the contact hole between the silicon substrate and the metal electrode comprising the second metal layer.
Claim 14
Dependent Claim
164 words
A semiconductor device comprising: a silicon substrate; a first silicon oxide film formed on the surface of said silicon substrate; a second silicon oxide film formed on said first silicon oxide film and containing boron and phosphorus; a contact hole selectively formed in said first and second silicon oxide films; an impurity diffusion layer formed on the surface layer of said silicon substrate at the bottom portion of said contact hole; a first metal film formed on said silicon oxide film and said impurity diffusion layer to serve as a barrier layer; and a second metal film of aluminum alloy containing silicon formed on said first metal film to serve as a metal electrode; said first metal film being formed of a material which prevents boron contained in said second silicon oxide film form being diffused into said second metal film and which prevents precipitation of silicon in the contact hole between the silicon substrate and the metal electrode comprising the second metal layer.
Claim 15
Dependent Claim
16 words
A semiconductor device in accordance with claim 12 wherein said first metal film comprises titanium nitride.
References Cited (Backward Citations)
US4271424A
Cited
US4321612A
Cited
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