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US4056642A
Expired / Lapsed
US
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Method of fabricating metal-semiconductor interfaces
Assignee: EMC Corp
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Filing: 1976-05-14
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Granted: 1977-11-01
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Expires: 1996-05-14
Abstract
Abstract An improved method of fabricating metal-semiconductor interfaces such as Schottky barriers and ohmic contacts. There is disclosed apparatus and method (or process) for chemically converting, etching, or passivating the surface of a material, such as the surface of a silicon wafer, in a gaseous plasma environment consisting of atomic, neutral nitrogen which causes the surface of the material to be resistant to otherwise subsequent nascent surface oxide buildup. This process is particularly useful in manufacture of Schottky diodes, transistors, and other electronic components or discrete and integrated devices requiring high quality metal-semiconductor junctions or interfaces.
Inventors
- 👤 Arjun N. Saxena
- 👤 Courtney Hart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:01
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/012; H10D64/0121; H10D64/011; H10D64/0111; H10D64/0112; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/694; H10P14/6943; H10P14/69433; H10P50/00; H10P50/20; Y; Y10; Y10S; Y10S438/00; Y10S438/906
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
68 words
A process for fabricating metal-semiconductor interface comprising the steps of: a. producing an oxidized semiconductor wafer with photo-resisted areas; b. subjecting the surface of said semiconductor wafer to a neutral, atomic, nitrogen plasma to break nascent oxide from said surface and to passivate said surface to make said surface resistant to nascent oxide buildup; and c. depositing said metal on said semiconductur wafer to obtain said metal-semiconductor interface.
Claim 2
Dependent Claim
68 words
A process for fabricating metal-semiconductor interface comprising the steps of: a. producing an oxidized semiconductor wafer with photo-resisted areas; b. subjecting the surface of said semiconductor wafer to a neutral, atomic, nitrogen plasma to break nascent oxide from said surface and to passivate said surface to make said surface resistant to nascent oxide buildup; and c. depositing said metal on said semiconductur wafer to obtain said metal-semiconductor interface.
Claim 3
Dependent Claim
26 words
A process as recited in claim 1, wherein said semiconductor is silicon, comprising the additional step of: d. heat-treating said interface to cause metal-silicide formation thereat.
Claim 4
Dependent Claim
26 words
A process as recited in claim 2 and wherein said metal is selected from the group consisting of platinum, molybdenum, aluminum, titanium, rhodium, palladium, and tungsten.
Claim 5
Dependent Claim
63 words
A process as recited in claim 3, wherein said metal is platinum and the temperature of said heat-treating step is controlled to be about 650° C, said subjecting step further comprising the step of: e. subjecting said silicon wafer to said nitrogen plasma under R.F. power of about 300 watts, at pressure of about one torr, for a duration of about five minutes.
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) | 1980-10-31 | 1981-05-02 | 1981-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-31 | 1985-05-02 | 1985-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-31 | 1989-05-02 | 1989-11-01 | $7700.00 | Window Closed / Lapsed |