US5821171A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Article comprising a gallium layer on a GaAs-based semiconductor, and method of making the article
Assignee: Nokia of America Corp
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Filing: 1995-03-22
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Granted: 1998-10-13
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Expires: 2015-03-22
Abstract
Abstract A high quality interface between a GaAs-based semiconductor and a Ga 2 O 3 dielectric an be formed if the semiconductor surface is caused to have less than 1% of a monolayer impurity coverage at completion of the first monolayer of the Ga 2 O 3 on the surface. This is achieved, for instance, by preparing the surface of a GaAs wafer under UHV conditions in a first growth chamber, transferring the wafer through a transfer module under UHV to a second growth chamber that is also under UHV, and growing the dielectric by evaporation of Ga 2 O 3 from a solid source, the process carried out such that the integrated impurity exposure of the surface is at most 100 Langmuirs. Articles according to the invention have low interface state density (<10 11 /cm 2 ·eV) and interface recombination velocity (<10 4 cm/s). Semiconductor/Ga 2 O 3 structures according to the invention can be used advantageously in a variety of electronic or optoelectronic devices, e.g., GaAs-based MOS-FETs, HBTs, lasers on solar cells.
Inventors
- 👤 Minghwei Hong
- 👤 Jueinai Raynien Kwo
- 👤 Joseph Petrus Mannaerts
- 👤 Matthias Passlack
- 👤 Fan Ren
- 👤 George John Zydzik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:38
CPC Classifications
H; H10; H10F; H10F99/00; H10D; H10D64/00; H10D64/60; H10D64/66; H10D64/68; H10D64/691; C; C23; C23C; C23C14/00; C23C14/06; C23C14/08; H10H; H10H20/00; H10H20/80; H10H20/84; H01; H01S; H01S5/00; H01S5/02; H01S5/028
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
169 words
A method of making an article that comprises a GaAs-based semiconductor body having a major surface, and that further comprises a layer of dielectric material on at least a portion of said major surface, at least the dielectric material at the dielectric/semiconductor interface consisting essentially of Ga 2 O 3 , the method comprising a) providing the semiconductor body; and b) forming the layer of dielectric material on the major surface, said forming comprising completion, at a time t m , of a first monolayer of dielectric material on the major surface; and the method further comprises c) preparing, prior to the forming step, the major surface such that, at a given point t c in time, at least said portion of the major surface is substantially atomically clean; and d) maintaining, at least from t c to t m , the semiconductor body in a reduced pressure atmosphere selected such that, at t m , the impurity coverage of the surface is less than 1% of a monolayer.
Claim 2
Independent Claim
169 words
A method of making an article that comprises a GaAs-based semiconductor body having a major surface, and that further comprises a layer of dielectric material on at least a portion of said major surface, at least the dielectric material at the dielectric/semiconductor interface consisting essentially of Ga 2 O 3 , the method comprising a) providing the semiconductor body; and b) forming the layer of dielectric material on the major surface, said forming comprising completion, at a time t m , of a first monolayer of dielectric material on the major surface; and the method further comprises c) preparing, prior to the forming step, the major surface such that, at a given point t c in time, at least said portion of the major surface is substantially atomically clean; and d) maintaining, at least from t c to t m , the semiconductor body in a reduced pressure atmosphere selected such that, at t m , the impurity coverage of the surface is less than 1% of a monolayer.
Claim 3
Dependent Claim
36 words
Method of claim 1, wherein the reduced pressure atmosphere is selected such that ##EQU4## p(t)dt is at most 100 Langmuirs, where p(t) is the impurity pressure of the reduced pressure atmosphere as a function of time.
Claim 4
Dependent Claim
10 words
Method of claim 1, wherein the major surface is (100)-oriented.
Claim 5
Dependent Claim
17 words
Method of claim 3, wherein the semiconductor body has composition GaAs at least at the dielectric/semiconductor interface.
Claim 6
Dependent Claim
49 words
Method of claim 1, wherein the semiconductor body comprises a GaAs layer formed in a first growth chamber, and wherein the method comprises transferring the semiconductor body from the first growth chamber to a second growth chamber through a vacuum chamber that connects the first and second growth chambers.
Claim 7
Dependent Claim
19 words
Method of claim 4, wherein the method is selected such that the major surface is a As-stabilized GaAs surface.
Claim 8
Dependent Claim
14 words
Method of claim 6, wherein the As-stabilized GaAs surface is a (100)-oriented C(4×2) surface.
Claim 9
Dependent Claim
10 words
Method of claim 1, wherein the major surface is (110)-oriented.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-10-12 | 2002-04-13 | 2002-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-12 | 2006-04-13 | 2006-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-12 | 2010-04-13 | 2010-10-13 | $7700.00 | Window Closed / Lapsed |