Patent US4157497A successfully refreshed from Google Patents.
US4157497A
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US
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Qualification test of gallium arsenide
Assignee: Boeing North American Inc
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Filing: 1978-01-05
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Granted: 1979-06-05
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Expires: 1998-01-05
Abstract
Abstract Semi-insulating GaAs material is qualified for ion implantation by taking a sample or samples from the material to be evaluated, polishing a surface of the sample, and chemically etching the surface to remove mechanical damage. The surface is bombarded with ions of an inert gas such as krypton, helium, argon, neon, or xenon. After bombardment, the sample is annealed and the sheet resistance is measured to determine if it meets a predetermined acceptable value.
Inventors
- 👤 Fred H. Eisen
- 👤 Ricardo Zucca
- 👤 Bryant Welch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:02
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; G01R31/2607; G01R31/2637
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
60 words
A method of qualifying GaAs semi-insulating substrate for ion implantation comprising the steps of: providing a semi-insulating, GaAs substrate; bombarding said substrate with inert gas ions selected from the group consisting of krypton, helium, argon, neon, and xenon; annealing the bombarded substrate; and measuring a predetermined electrical property of the bombarded substrate to determine if it meets a predetermined value.
Claim 2
Independent Claim
60 words
A method of qualifying GaAs semi-insulating substrate for ion implantation comprising the steps of: providing a semi-insulating, GaAs substrate; bombarding said substrate with inert gas ions selected from the group consisting of krypton, helium, argon, neon, and xenon; annealing the bombarded substrate; and measuring a predetermined electrical property of the bombarded substrate to determine if it meets a predetermined value.
Claim 3
Dependent Claim
46 words
The method as claimed in claim 1, wherein said step of providing a substrate comprises; taking a sample from an end of a GaAs boule; polishing at least one surface of said sample; and removing mechanical damage from the polished surface by chemically etching said surface.
Claim 4
Dependent Claim
35 words
The method as claimed in claim 2, wherein said step of annealing comprises: providing a means for protecting said surface during heating; and heating said surface at 800° to 900° C. for approximately one half-hour.
Claim 5
Dependent Claim
28 words
The method as claimed in claim 3, wherein step of providing a means for protecting said surface comprises providing a Si 3 N 4 cap on said surface.
Claim 6
Dependent Claim
29 words
The method as claimed in claim 1, wherein said step of measuring a predetermined electrical property of said bombarded substrate comprises measuring the sheet resistance of said bombarded substrate.
Claim 7
Dependent Claim
28 words
The method as claimed in claim 5, wherein said step of measuring the sheet resistance of said bombarded substrate is accomplished by utilizing the Van der Pauw method.
Claim 8
Independent Claim
82 words
A method of qualifying GaAs semi-insulating substrate for ion implantation comprising the steps of: providing a semi-insulating, GaAs substrate; bombarding said substrate with inert gas ions selected from the group consisting of krypton, helium, argon, neon, and xenon; providing a Si 3 N 4 cap on a surface of said substrate to protect said surface; heating said substrate at 800° to 900° C. for approximately one half-hour; and measuring the sheet resistance of said bombarded substrate by the Van der Pauw method.
Claim 9
Independent Claim
82 words
A method of qualifying GaAs semi-insulating substrate for ion implantation comprising the steps of: providing a semi-insulating, GaAs substrate; bombarding said substrate with inert gas ions selected from the group consisting of krypton, helium, argon, neon, and xenon; providing a Si 3 N 4 cap on a surface of said substrate to protect said surface; heating said substrate at 800° to 900° C. for approximately one half-hour; and measuring the sheet resistance of said bombarded substrate by the Van der Pauw method.
References Cited (Backward Citations)
US3290179A
Cited
US4058413A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-06-04 | 1982-12-04 | 1983-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-04 | 1986-12-04 | 1987-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-04 | 1990-12-04 | 1991-06-05 | $7700.00 | Window Closed / Lapsed |