US4311730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thick film circuits
Assignee: Plessey Inc
•
Filing: 1980-03-20
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Granted: 1982-01-19
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Expires: 2000-03-20
Abstract
Abstract A thick film resistor suitable for deposition on a copper printed circuit is produced by providing a resistor pattern of a mixture of metal powder and oxide of the metal and heating in a nitrogen atmosphere at a temperature such that the metal and the metallic oxide react to produce a conducting lower oxide.
Inventors
- 👤 David J. Pedder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:26
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/06533
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
77 words
A method of producing a thick film resistor compatible with a copper conductor including providing a pattern of a mixture on a ceramic surface, said mixture comprising a metal powder and an oxide of the metal, and heating the patterned ceramic in an inert gas atmosphere such that the metal and the metallic oxide react to produce a conducting layer oxide, in which the metal is molybdenum and the metallic oxide is molybdic oxide MoO 3 ).
Claim 2
Independent Claim
77 words
A method of producing a thick film resistor compatible with a copper conductor including providing a pattern of a mixture on a ceramic surface, said mixture comprising a metal powder and an oxide of the metal, and heating the patterned ceramic in an inert gas atmosphere such that the metal and the metallic oxide react to produce a conducting layer oxide, in which the metal is molybdenum and the metallic oxide is molybdic oxide MoO 3 ).
Claim 3
Dependent Claim
20 words
A method of producing a thick film resistor as claimed in claim 1 in which the inert gas is nitrogen.
Claim 4
Dependent Claim
39 words
A method of producing a thick film resistor as claimed in claim 1 in which small proportions of tungsten metal and/or vanadium pentoxide are added to the mixture to give a negative shift in temperature coefficient of resistance values.
References Cited (Backward Citations)
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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) | 1985-01-18 | 1985-07-20 | 1986-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-18 | 1989-07-20 | 1990-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-18 | 1993-07-20 | 1994-01-19 | $7700.00 | Window Closed / Lapsed |