Patent US3390449A successfully refreshed from Google Patents.
US3390449A
Expired / Lapsed
US
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Method for preparation and encapsulation of germanium gamma ray detectors
Assignee: United States Atomic Energy Commission
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Filing: 1966-07-18
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Granted: 1968-07-02
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Expires: 1986-07-18
Abstract
No abstract record available.
Inventors
- 👤 Richard J Fox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:04
CPC Classifications
B; B21; B21D; B21D51/00; B21D51/16; B21D51/38; B21D51/44; H; H10; H10F; H10F99/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
A METHOD OF MAKING A GERMANIUM GAMMA RAY DETECTOR COMPRISING THE STPES OF SLICING P-TYPE GERMANIUM INTO A WAFER, LAPPING ONE FACE OF THE WFER, ETCHING THE OPPOSITE FACE AND OUTER EDGE OF THE WAFER, THEN DEPOSITING A METALLIC COATING OF LI METAL ON THE ETCHED FACE BY VACUUM EVAPORATION, HEATING THE WAFER TO DIFFUSE A PORTION OF THE LI AND CONVERT THE ETCHED FACE TO N-TYPE, REMOVING THE EXCESS LI FROM THE FACE, ETCHING THE SAID OPPOSITE FACE AND OUTER EDGE AGAIN, ATTACHING THE LAPPED FACE OF SAID WAFER TO A HEAT SINK, AND THEN APPLYING AN ELECTRODE TO THE ETCHED FACE OF THE WAFER AND DRIFTING THE LI TO COMPENSATE THE CRYSTAL, AND ETCHING SAID OPPOSITE FACE AGAIN AND APPLYING A LI PROTECTIVE COATING THERETO BY VACUUM EVAPORATION.
Claim 2
Independent Claim
130 words
A METHOD OF MAKING A GERMANIUM GAMMA RAY DETECTOR COMPRISING THE STPES OF SLICING P-TYPE GERMANIUM INTO A WAFER, LAPPING ONE FACE OF THE WFER, ETCHING THE OPPOSITE FACE AND OUTER EDGE OF THE WAFER, THEN DEPOSITING A METALLIC COATING OF LI METAL ON THE ETCHED FACE BY VACUUM EVAPORATION, HEATING THE WAFER TO DIFFUSE A PORTION OF THE LI AND CONVERT THE ETCHED FACE TO N-TYPE, REMOVING THE EXCESS LI FROM THE FACE, ETCHING THE SAID OPPOSITE FACE AND OUTER EDGE AGAIN, ATTACHING THE LAPPED FACE OF SAID WAFER TO A HEAT SINK, AND THEN APPLYING AN ELECTRODE TO THE ETCHED FACE OF THE WAFER AND DRIFTING THE LI TO COMPENSATE THE CRYSTAL, AND ETCHING SAID OPPOSITE FACE AGAIN AND APPLYING A LI PROTECTIVE COATING THERETO BY VACUUM EVAPORATION.
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) | 1971-07-02 | 1972-01-01 | 1972-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-07-02 | 1976-01-01 | 1976-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-07-02 | 1980-01-01 | 1980-07-02 | $7700.00 | Window Closed / Lapsed |