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US4448633A
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US
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Passivation of III-V semiconductor surfaces by plasma nitridation
Assignee: RTX Corp
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Filing: 1982-11-29
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Granted: 1984-05-15
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Expires: 2002-11-29
Abstract
Abstract Type III-V compound semiconductor surfaces are passivated by exposure to a low pressure nitrogen plasma. The III element forms III element-nitride. Nitridation is performed in two steps; the first being at a low temperature to prevent decomposition of the surface by loss of V element, and the second step being performed at an elevated temperature at which nitridation proceeds at a faster rate. The resultant articles have a III element-nitride surface layer which protects the articles from environmental degradation while reducing the surface state density and permitting inversion of the surface layer.
Inventors
- 👤 Alexander J. Shuskus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:15
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6316; H10P14/6319; H10P14/68; Y; Y10; Y10S; Y10S438/00; Y10S438/958
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
152 words
Method for producing surface passivating layers on III-V semiconductor articles by nitriding the surface of the articles including the steps of: (a) heating the III-V article to a temperature greater than about 400° C. and less than 500° C. while contacting the III-V article with a nitrogen plasma, said plasma having been produced by ionizing nitrogen gas having a pressure of from about 0.01 to about 10 torr, to provide an initial III-nitride layer having a thickness of about 20-100 Å, and (b) heating the III-V semiconductor to a temperature greater than 500° C. and less than about 700° C. while contacting the III-V surface with a nitrogen plasma to produce a thicker nitride layer, said plasma having been produced by ionizing nitrogen gas having a pressure of from about 0.01 to about 10 torr, so that the total thickness of the nitride layer is from about 200 to about 1000 Å.
Claim 2
Dependent Claim
152 words
Method for producing surface passivating layers on III-V semiconductor articles by nitriding the surface of the articles including the steps of: (a) heating the III-V article to a temperature greater than about 400° C. and less than 500° C. while contacting the III-V article with a nitrogen plasma, said plasma having been produced by ionizing nitrogen gas having a pressure of from about 0.01 to about 10 torr, to provide an initial III-nitride layer having a thickness of about 20-100 Å, and (b) heating the III-V semiconductor to a temperature greater than 500° C. and less than about 700° C. while contacting the III-V surface with a nitrogen plasma to produce a thicker nitride layer, said plasma having been produced by ionizing nitrogen gas having a pressure of from about 0.01 to about 10 torr, so that the total thickness of the nitride layer is from about 200 to about 1000 Å.
Claim 3
Dependent Claim
19 words
A method as in claim 1 in which, following the second nitriding step, the article is annealed in hydrogen.
Claim 4
Dependent Claim
18 words
A method as in claim 2 in which the III-V semiconductor is GaAs and the III-nitride is GaN.
Claim 5
Dependent Claim
18 words
A method as in claim 1 in which the III-V semiconductor is GaAs and the III-nitride is GaN.
Claim 6
Dependent Claim
39 words
A method as in claim 1 in which the pressure of the nitrogen from which the plasma is produced in steps (a) and (b) is from about 0.01 to about 0.5 torr and the resulting III-nitride coating is polycrystalline.
Claim 7
Dependent Claim
41 words
A method as in claim 1 in which the pressure of the nitrogen from which the plasma is produced in steps (a) and (b) is from about 1 to about 10 torr and the resulting III-nitride coating is a single crystal.
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) | 1987-05-15 | 1987-11-14 | 1988-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-15 | 1991-11-14 | 1992-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-15 | 1995-11-14 | 1996-05-15 | $7700.00 | Window Closed / Lapsed |