US4665295A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser make-link programming of semiconductor devices
Assignee: Texas Instruments Inc
•
Filing: 1984-08-02
•
Granted: 1987-05-12
•
Expires: 2004-08-02
Abstract
Abstract A semiconductor device is programmed by a laser beam which causes an electrical short between two conductors on a silicon substrate, as by melting an insulator between the conductors and fusing or shorting the conductors. The conductors may be first and second levels of polycrystalline silicon in a standard double-level poly process, and the insulator is thermal silicon oxide. The laser beam is focused on an area which is shielded from the silicon substrate by the first-level conductor, so heating and disruption of the substrate or underlying circuit structure is minimized.
Inventors
- 👤 James M. McDavid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:31
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/49; H10W20/493; H10W20/494; H10P; H10P34/00; H10P34/40; H10P34/42
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
120 words
A laser beam programmable semiconductor device, comprising: an upper electrically conductive strip having an opening therein defining a laser programmable area; a lower electrically conductive layer a portion of which underlies the opening; and an electrical insulating layer separating said strip and lower conductive layer being sufficiently thin so that upon being impinged by a laser beam the insulating layer below the opening disintegrates and the laser beam melts the upper conductive strip and lower conductive layer so as to fuse the two together; and wherein the opening in said upper strip is sufficiently large such that a substantial fraction of the laser beam passes through the opening and a portion thereof irradiates and melts edges of the conductive strip.
Claim 2
Dependent Claim
120 words
A laser beam programmable semiconductor device, comprising: an upper electrically conductive strip having an opening therein defining a laser programmable area; a lower electrically conductive layer a portion of which underlies the opening; and an electrical insulating layer separating said strip and lower conductive layer being sufficiently thin so that upon being impinged by a laser beam the insulating layer below the opening disintegrates and the laser beam melts the upper conductive strip and lower conductive layer so as to fuse the two together; and wherein the opening in said upper strip is sufficiently large such that a substantial fraction of the laser beam passes through the opening and a portion thereof irradiates and melts edges of the conductive strip.
Claim 3
Dependent Claim
18 words
A device according to claim 1, wherein said upper conductive strip and lower conductive layer are polycrystalline silicon.
Claim 4
Dependent Claim
14 words
A device according to claim 1, wherein said electrical insulating layer is silicon oxide.
Claim 5
Dependent Claim
35 words
A device according to claim 1, wherein said upper conductive strip is a strip extending along a face of a semiconductor body and the opening therein is substantially smaller than the width of said strip.
Claim 6
Dependent Claim
53 words
A device according to claim 1, wherein said upper conductive strip is a strip extending along a face of a semiconductor body and the opening therein is a gap dividing said strip into two parts and said lower conductive layer is wider than said strip in a region of said laser programmable area.
Claim 7
Independent Claim
115 words
A method of making a semiconductor device, comprising the steps of: forming an upper electrically conductive strip having an opening therein defining a beam programmable area which is a substantial proportion of the cross-sectional area of a beam, a lower electrically conductive layer with a portion thereof underlying the upper conductive strip and an electrically insulating layer separating said strip and lower conductive layer sufficiently thin so as to be capable of disintegrating upon being impinged by the beam; and irradiating said programming area of the face with the beam impinging upon the conductive strip and layer and said insulating layer so as to create a conductive path between said upper strip and lower layer.
Claim 8
Independent Claim
115 words
A method of making a semiconductor device, comprising the steps of: forming an upper electrically conductive strip having an opening therein defining a beam programmable area which is a substantial proportion of the cross-sectional area of a beam, a lower electrically conductive layer with a portion thereof underlying the upper conductive strip and an electrically insulating layer separating said strip and lower conductive layer sufficiently thin so as to be capable of disintegrating upon being impinged by the beam; and irradiating said programming area of the face with the beam impinging upon the conductive strip and layer and said insulating layer so as to create a conductive path between said upper strip and lower layer.
Claim 9
Dependent Claim
13 words
A method according to claim 6, wherein said beam is a laser beam.
Claim 10
Dependent Claim
38 words
A method according to claim 6, wherein the width of the opening is less than the width of said beam so that the portion of said upper conductive strip around the opening shields said body from said beam.
Claim 11
Dependent Claim
23 words
A method according to claim 6, wherein the width of the opening is less than that of said underlying lower electrically conductive layer.
Claim 12
Dependent Claim
19 words
A method according to claim 8, wherein said lower conductive layer and said upper conductive strip are polycrystalline silicon.
Claim 13
Dependent Claim
18 words
A method according to claim 9, wherein said lower conductive layer and upper conductive strip are polycrystalline silicon.
Claim 14
Dependent Claim
24 words
A method according to claim 8, wherein said insulating layer is silicon dioxide which is eroded away in said programming area by said beam.
Claim 15
Dependent Claim
24 words
A method according to claim 9, wherein said insulating layer is silicon dioxide which is eroded away in said programming area by said beam.
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) | 1990-05-11 | 1990-11-10 | 1991-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-11 | 1994-11-10 | 1995-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-11 | 1998-11-10 | 1999-05-12 | $7700.00 | Window Closed / Lapsed |