US4374314A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser template trimming of circuit elements
Assignee: Analog Devices Inc
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Filing: 1981-08-17
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Granted: 1983-02-15
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Expires: 2001-08-17
Abstract
Abstract This invention relates to a method of trimming an element of an integrated circuit with a laser beam. A reflective, or otherwise optically opaque, template-like layer is placed over a portion of the circuit element to control the trimming operation. The laser beam is directed along the sharp edge of this layer in such a way that the maximum energy portion of the beam strikes a part of the circuit element, while low energy portions of the beam are prevented from reaching other parts of the element where they might adversely affect its characteristics.
Inventors
- 👤 James J. Deacutis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:36
CPC Classifications
H; H10; H10P; H10P34/00; H10P34/40; H10P34/42
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
156 words
The method of laser trimming a thin film circuit element supported on a substrate and coated with a generally non-conductive, optically transparent overlayer comprising: depositing on said overlayer an optically opaque coating having an edge aligned with a desired trim boundary of said circuit element; providing a laser having an output beam with a non-uniform cross-sectional energy distribution wherein the maximum energy is concentrated near the center, and a wavelength substantially absorbed by said circuit element and blocked by said opaque coating; directing said laser beam at the edge of said opaque coating with its peak energy approximately adjacent said edge, to penetrate and volatilize a portion of said circuit element with the maximum energy region of said beam; and relatively moving said beam along said edge to thereby trim a selected region from said circuit element while substantially avoiding contact of low energy portions of said beam with the remaining portion of said circuit element.
Claim 2
Independent Claim
156 words
The method of laser trimming a thin film circuit element supported on a substrate and coated with a generally non-conductive, optically transparent overlayer comprising: depositing on said overlayer an optically opaque coating having an edge aligned with a desired trim boundary of said circuit element; providing a laser having an output beam with a non-uniform cross-sectional energy distribution wherein the maximum energy is concentrated near the center, and a wavelength substantially absorbed by said circuit element and blocked by said opaque coating; directing said laser beam at the edge of said opaque coating with its peak energy approximately adjacent said edge, to penetrate and volatilize a portion of said circuit element with the maximum energy region of said beam; and relatively moving said beam along said edge to thereby trim a selected region from said circuit element while substantially avoiding contact of low energy portions of said beam with the remaining portion of said circuit element.
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein said opaque coating is reflective of said laser beam.
Claim 4
Dependent Claim
11 words
The method of claim 2 wherein said opaque coating is aluminum.
Claim 5
Dependent Claim
11 words
The method of claim 2 wherein said opaque coating is copper.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein said opaque coating absorbs the energy of said laser beam.
References Cited (Backward Citations)
US3699649A
Cited
US4179310A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-14 | 1986-08-16 | 1987-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-14 | 1990-08-16 | 1991-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-14 | 1994-08-16 | 1995-02-15 | $7700.00 | Window Closed / Lapsed |