US4855798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor and process of fabrication thereof
Assignee: Texas Instruments Inc
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Filing: 1988-12-13
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Granted: 1989-08-08
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Expires: 2008-12-13
Abstract
Abstract A semiconductor device having a salicide (self-aligned silicide) configuration and operable as, for example, a dynamic RAM device is fabricated by preparing a semiconductor substrate, forming a layer of silicon in, on or over the semiconductor substrate, forming a layer of a metal on the layer of silicon, the metal silicide layer having a surface portion, and heating the resultant structure in the presence of a reaction ambient containing nitride for forming on the layer of silicon a layer of a metal silicide having a surface portion and nitriding the surface portion to form a nitride layer consisting of a nitride of said metal silicide.
Inventors
- 👤 Youichiro Imamura
- 👤 Toshiyuki Kaeriyama
- 👤 Hironori Ishimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:21
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6316; Y; Y10; Y10S; Y10S257/00; Y10S257/915
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
33 words
A semiconductor device comprising (a) a layer of a metal silicide having a surface portion, and (b) a nitride layer forming said surface portion and consisting of a nitride of said metal silicide.
Claim 2
Dependent Claim
33 words
A semiconductor device comprising (a) a layer of a metal silicide having a surface portion, and (b) a nitride layer forming said surface portion and consisting of a nitride of said metal silicide.
Claim 3
Dependent Claim
42 words
A process of fabricating a semiconductor device, comprising the steps of (a) forming a layer of a metal silicide having a surface portion, and (b) nitriding said surface portion to form a nitride layer consisting of a nitride of said metal silicide.
Claim 4
Dependent Claim
42 words
A process of fabricating a semiconductor device, comprising the steps of (a) forming a layer of a metal silicide having a surface portion, and (b) nitriding said surface portion to form a nitride layer consisting of a nitride of said metal silicide.
Claim 5
Dependent Claim
98 words
A process of fabricating a semiconductor device, comprising the steps of (a) preparing a semiconductor substrate, (b) forming a layer of silicon in conjunction with said semiconductor substrate, (c) forming a layer of a metal on said layer of silicon, the metal silicide layer having a surface portion, and (d) heating the resultant structure in the presence of a reaction ambient containing nitride for forming on said layer of silicon a layer of a metal silicide having a surface portion and nitriding said surface portion to form a nitride layer consisting of a nitride of said metal silicide.
Claim 6
Dependent Claim
98 words
A process of fabricating a semiconductor device, comprising the steps of (a) preparing a semiconductor substrate, (b) forming a layer of silicon in conjunction with said semiconductor substrate, (c) forming a layer of a metal on said layer of silicon, the metal silicide layer having a surface portion, and (d) heating the resultant structure in the presence of a reaction ambient containing nitride for forming on said layer of silicon a layer of a metal silicide having a surface portion and nitriding said surface portion to form a nitride layer consisting of a nitride of said metal silicide.
Claim 7
Dependent Claim
32 words
A process as set forth in claim 3, wherein said structure is heated at a temperature within the range of from about 550° C. to about 600° C. at a subatmospheric pressure.
Claim 8
Dependent Claim
36 words
A process as set forth in claim 3, wherein said structure is heated at a temperature within the range of from about 550° C. to about 600° C. at a pressure of about 10 -2 Torr.
Claim 9
Dependent Claim
27 words
A semiconductor device as set forth in claim 1, further including a semiconductor substrate, and said layer of a metal silicide being disposed over said semiconductor substrate.
Claim 10
Dependent Claim
49 words
A semiconductor device as set forth in claim 6, wherein a layer of polysilicon is interposed between said semiconductor substrate and said layer of a metal silicide so as to dispose said polysilicon layer over said semiconductor substrate, and said layer of a metal silicide on said polysilicon layer.
Claim 11
Dependent Claim
34 words
A semiconductor device as set forth in claim 6, further including a layer of doped silicon in said semiconductor substrate, said layer of a metal silicide being disposed on the layer of doped silicon.
Claim 12
Dependent Claim
20 words
A semiconductor device as set forth in claim 1, wherein said metal silicide layer has a thickness of about 1200-Å.
Claim 13
Dependent Claim
30 words
A semiconductor device as set forth in claim 7, wherein said polysilicon layer has a thickness of about 4500-Å and said metal silicide layer has a thickness of about 1200-Å.
Claim 14
Dependent Claim
39 words
A semiconductor device as set forth in claim 7, wherein said metal silicide layer has a thickness of about 1200-Å including the thickness of the nitride layer disposed thereon, and said polysilicon layer has a thickness of about 4500-Å.
Claim 15
Dependent Claim
19 words
A semiconductor device as set forth in claim 11, wherein said nitride layer has a thickness of about 1000-Å.
Claim 16
Dependent Claim
26 words
A process as set forth in claim 2, further including preparing a semiconductor substrate, and forming said layer of a metal silicide over said semiconductor substrate.
Claim 17
Dependent Claim
52 words
A process as set forth in claim 13, further including forming a layer of polysilicon over said semiconductor substrate prior to the formation of said layer of a metal silicide so as to position said layer of polysilicon between said semiconductor substrate and the subsequently formed said layer of a metal silicide.
Claim 18
Dependent Claim
35 words
A process as set forth in claim 13, further including forming a layer of doped silicon in said semiconductor substrate, and thereafter forming said layer of a metal silicide on said layer of doped silicon.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-07 | 1993-02-06 | 1993-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-07 | 1997-02-06 | 1997-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-07 | 2001-02-06 | 2001-08-08 | $7700.00 | Window Closed / Lapsed |