US5021362A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser link blowing in integrateed circuit fabrication
Assignee: Nokia Bell Labs
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Filing: 1989-12-29
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Granted: 1991-06-04
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Expires: 2009-12-29
Abstract
Abstract A single beam of radiation is split and part of the beam is directed to conductive links, e.g. runners on a substrate. Analysis of the incident beam and the beam reflected from the substrate permits a determination of when the link is blown and rendered non-conductive and when significant substrate involvement occurs.
Inventors
- 👤 James D. Chlipala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:55
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/49; H10W20/493; H10W20/494
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
101 words
A method of integrated circuit manufacture in which portions of the circuit are rendered non-conductive by the application of incident radiation energy, said method comprising the steps of: Illuminating said portions of said integrated circuit which are desired to be rendered non-conductive with a beam of radiation, said portions comprising an electrically conducting material on a non-conducting substrate; and, analyzing the incident and reflected radiation intensities to determine if said portions were redered non conductive, and increasing the output of said laser if said portions were not rendered non-conductive or decreasing the output of said laser if significant substrate involvement occurred.
Claim 2
Independent Claim
101 words
A method of integrated circuit manufacture in which portions of the circuit are rendered non-conductive by the application of incident radiation energy, said method comprising the steps of: Illuminating said portions of said integrated circuit which are desired to be rendered non-conductive with a beam of radiation, said portions comprising an electrically conducting material on a non-conducting substrate; and, analyzing the incident and reflected radiation intensities to determine if said portions were redered non conductive, and increasing the output of said laser if said portions were not rendered non-conductive or decreasing the output of said laser if significant substrate involvement occurred.
Claim 3
Dependent Claim
16 words
A method as recited in claim 1 in which the source of rediation comprises a laser.
Claim 4
Dependent Claim
25 words
A method as recited in claim 2 comprising further step of comparing said incident and reflected energy intensities to determine if significant substrate involvement occurred.
Claim 5
Dependent Claim
16 words
A method as recited in claim 3 in which said comparing step uses the perturded reflectivity.
Claim 6
Dependent Claim
26 words
A method as recited in claim 1 in which said analyzing step uses a derivative of at least one of said incident and reflected beam intensities.
Claim 7
Dependent Claim
29 words
A method as recited in claim 3 comprising the further step of monitoring the incident pulse energy and determining if it is above or below threshold for link blowing.
References Cited (Backward Citations)
DE241562C
Cited
JPS5317078A
Cited
US4720620A
Cited
US4816422A
Cited
US4853758A
Cited
US4902631A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-03 | 1994-12-03 | 1995-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-03 | 1998-12-03 | 1999-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-03 | 2002-12-03 | 2003-06-04 | $7700.00 | Window Closed / Lapsed |