US3661676A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of single crystal aluminum oxide
Assignee: United States Department of the Army
•
Filing: 1970-05-04
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Granted: 1972-05-09
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Expires: 1990-05-04
Abstract
Abstract A method for the production of large single-crystals of Al2O3 comprising the positioning of several small single-crystals of Al2O3 on a substrate in a chamber, the catalytic oxidation of AlCl3 in the presence of water vapor in the chamber and adjacent to the surfaces of the small single-crystals of Al2O3 to form Al2O3 and HCl gas. The produced Al2O3 being deposited on the surfaces of the small single crystals of Al2O3 to form a large single-crystal of Al2O3.
Inventors
- 👤 Philip Wong
- 👤 Donald R Messier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:08
CPC Classifications
C; C30; C30B; C30B29/00; Y; Y10; Y10S; Y10S148/00; Y10S148/118; Y10S148/15
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
18 words
A method in accordance with claim 1, wherein the reaction is continued for a period of 6 hours.
Claim 2
Dependent Claim
21 words
A method in accordance with claim 2 wherein the total gas flow is at the rate of 1.5 liters per minute.
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) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |