US5266529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Focused ion beam for thin film resistor trim on aluminum nitride substrates
Assignee: Northrop Grumman Corp
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Filing: 1991-10-21
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Granted: 1993-11-30
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Expires: 2011-10-21
Abstract
Abstract A method for trimming thin film resistors. A focused inert ion beam is employed to selectively remove portions of a resistive film deposited on a substrate.
Inventors
- 👤 James C. Lau
- 👤 Maurice Lowery
- 👤 Kenneth Lui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:30
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/40; H10D1/47; H01; H01C; H01C17/00; H01C17/22; H01C17/24; H01C17/2404; H10P; H10P95/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
86 words
A method of fabricating a thin film resistor with a precise resistance value comprising the steps of: forming a thin film of resistive material on an aluminum nitride substrate; attaching a pair of conductor pads directly to said thin film, said conductor pads being spaced from one another and from said substrate, said conductor pads being adaptable to electrically couple said resistive material to a circuit; and selectively removing portions of said thin film of resistive material with a exposing a corresponding area of said substrate.
Claim 2
Independent Claim
86 words
A method of fabricating a thin film resistor with a precise resistance value comprising the steps of: forming a thin film of resistive material on an aluminum nitride substrate; attaching a pair of conductor pads directly to said thin film, said conductor pads being spaced from one another and from said substrate, said conductor pads being adaptable to electrically couple said resistive material to a circuit; and selectively removing portions of said thin film of resistive material with a exposing a corresponding area of said substrate.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said ion beam is an inert beam.
Claim 4
Dependent Claim
13 words
The method of claim 1 wherein said ion beam is an Argon beam.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein said thin film of resistive material is nickel chromium (nichrome) or tantalum nitride.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein an L-shaped portion is removed from said thin film.
Claim 7
Dependent Claim
15 words
The method of claim 5 wherein said L-shaped portion abuts an edge of said resistor.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein said beam is approximately 500 to 10,000 angstroms in diameter.
Claim 9
Independent Claim
109 words
A method of fabricating a thin film resistor with a precise resistance value comprising the steps of: forming a thin film of nickel chromium (nichrome) on an aluminum nitride substrate, said substrate having an edge; attaching a pair of conductor pads directly to said thin film, said pads being spaced from one another and from said substrate, said pads adapted to electrically couple said nickel chromium to a circuit; and removing an L-shaped portion of said film of nickel chromium with a focused ion beam to increase the total resistance of said resistor by exposing a corresponding area of said substrate, said L-shaped portion extending from said substrate edge.
Claim 10
Independent Claim
109 words
A method of fabricating a thin film resistor with a precise resistance value comprising the steps of: forming a thin film of nickel chromium (nichrome) on an aluminum nitride substrate, said substrate having an edge; attaching a pair of conductor pads directly to said thin film, said pads being spaced from one another and from said substrate, said pads adapted to electrically couple said nickel chromium to a circuit; and removing an L-shaped portion of said film of nickel chromium with a focused ion beam to increase the total resistance of said resistor by exposing a corresponding area of said substrate, said L-shaped portion extending from said substrate edge.
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) | 1996-11-29 | 1997-05-31 | 1997-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-29 | 2001-05-31 | 2001-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-29 | 2005-05-31 | 2005-11-30 | $7700.00 | Window Closed / Lapsed |