US3308528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of cermet film resistors to close tolerances
Assignee: International Business Machines Corp
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Filing: 1963-11-06
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Granted: 1967-03-14
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Expires: 1983-11-06
Abstract
No abstract record available.
Inventors
- 👤 Robert L Bullard
- 👤 Robert A Hasbrouck
- 👤 Philip S Schlemmer
- 👤 Rudolf E Thun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:04
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/22; H01C17/26; H01C17/265; H01C17/267; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49099
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
A METHOD OF FABRICATING A CERMET THIN FILM RESISTOR TO A PREDETERMINED DESIGN RESISTIVITY COMPRISING PROVIDING A SUBSTRATE AND FORMING THEREON CONDUCTIVE TERMINAL ELEMENTS AND A CHROMIUM-SILICON MONOXIDE CERMET FILM IN LAPPED RELATION TO FORM AN ELECTRICAL CIRCUIT PATH BETWEEN SAID ELEMENTS THROUGH SAID FILM, SAID FILM HAVING A RESISTIVITY GREATER THAN SAID DESIGN RESISTIVITY AND BEING ENCAPSULATED COMPLETELY IN SILICON MONOXIDE, THEN ANNEALING SAID FILM BY SUBJECTING THE SAME TO A TEMPERATURE OF ABOUT 400*C. IN AN OVEN UNTIL THE RESISTIVITY OF SAID FILM APPROACHES SAID DESIGN RESISTIVITY, AND FINALLY HEATING THE CERMET FILM CIRCUIT ELEMENT TO A FURTHER ANNEALING TEMPERATURE BY PASSING ELECTRICAL CURRENT THROUGH SAID ELEMENT UNTIL THE RESISTIVITY OF SAID FILM REACHES SAID DESIGN RESISTIVITY.
Claim 2
Independent Claim
119 words
A METHOD OF FABRICATING A CERMET THIN FILM RESISTOR TO A PREDETERMINED DESIGN RESISTIVITY COMPRISING PROVIDING A SUBSTRATE AND FORMING THEREON CONDUCTIVE TERMINAL ELEMENTS AND A CHROMIUM-SILICON MONOXIDE CERMET FILM IN LAPPED RELATION TO FORM AN ELECTRICAL CIRCUIT PATH BETWEEN SAID ELEMENTS THROUGH SAID FILM, SAID FILM HAVING A RESISTIVITY GREATER THAN SAID DESIGN RESISTIVITY AND BEING ENCAPSULATED COMPLETELY IN SILICON MONOXIDE, THEN ANNEALING SAID FILM BY SUBJECTING THE SAME TO A TEMPERATURE OF ABOUT 400*C. IN AN OVEN UNTIL THE RESISTIVITY OF SAID FILM APPROACHES SAID DESIGN RESISTIVITY, AND FINALLY HEATING THE CERMET FILM CIRCUIT ELEMENT TO A FURTHER ANNEALING TEMPERATURE BY PASSING ELECTRICAL CURRENT THROUGH SAID ELEMENT UNTIL THE RESISTIVITY OF SAID FILM REACHES SAID DESIGN RESISTIVITY.
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) | 1970-03-13 | 1970-09-12 | 1971-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-03-13 | 1974-09-12 | 1975-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-03-13 | 1978-09-12 | 1979-03-14 | $7700.00 | Window Closed / Lapsed |