Patent US5023589A successfully refreshed from Google Patents.
US5023589A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gold diffusion thin film resistors and process
Assignee: VISHAY EFI Inc
•
Filing: 1989-09-08
•
Granted: 1991-06-11
•
Expires: 2009-09-08
Abstract
Abstract A low-resistance nickel-chromium-based thin film resistor and method for forming same. A nickel-chromium alloy film is coated on at least one side with a layer of gold, the resulting gold-coated alloy film is heated at a temperature and for a time effective to cause diffusion of sufficient gold into the nickel-chromium film to lower its resistance to a desired value, and the gold layer is then removed, to leave a nickel-chromium-gold composite film resistor.
Inventors
- 👤 Allen T. Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:48
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/006; C; C23; C23C; C23C14/00; C23C14/06; C23C14/14; C23C14/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
68 words
A thin film resistor, comprising: a film of nickel-chromium alloy; and gold diffused in at least one surface of said alloy film in an amount sufficient to cause the resistivity of the resulting composite to be between the resistivity of gold and the resistivity of said nickel-chromium alloy the diffused gold having a concentration gradient which is of highest concentration at or near said at least one surface.
Claim 2
Dependent Claim
68 words
A thin film resistor, comprising: a film of nickel-chromium alloy; and gold diffused in at least one surface of said alloy film in an amount sufficient to cause the resistivity of the resulting composite to be between the resistivity of gold and the resistivity of said nickel-chromium alloy the diffused gold having a concentration gradient which is of highest concentration at or near said at least one surface.
Claim 3
Dependent Claim
32 words
The thin film resistor of claim 1 wherein said nickel-chromium alloy film contains 18 to 25% by weight nickel, 65 to 75% by weight chromium, and 7 to 12% by weight aluminum.
Claim 4
Dependent Claim
19 words
The thin film resistor of claim 1 wherein said nickel-chromium film has a thickness of 100 to 500 Å.
Claim 5
Dependent Claim
19 words
The thin film resistor of claim 1 wherein the resistivity of said resistor is between 1 and 10 ohm-cm.
Claim 6
Dependent Claim
31 words
The thin film resistor of claim 1 wherein the temperature coefficient of resistance of said resistor is substantially the same as the temperature coefficient of resistance of the nickel-chromium alloy film.
References Cited (Backward Citations)
US4205299A
Cited
US4204935A
Cited
US4164607A
Cited
US4692230A
Cited
US4725480A
Cited
US4803457A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-10 | 1994-12-10 | 1995-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-10 | 1998-12-10 | 1999-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-10 | 2002-12-10 | 2003-06-11 | $7700.00 | Window Closed / Lapsed |