Patent US4027319A successfully refreshed from Google Patents.
US4027319A
Expired / Lapsed
US
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Schottky barrier phototransistor
Assignee: Texas Instruments Inc
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Filing: 1973-05-29
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Granted: 1977-05-31
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Expires: 1993-05-29
Abstract
Abstract Disclosed is a phototransistor comprised of an indium arsenide n-type semiconductor substrate, a thin, relatively lightly doped p-type cadmium diffused region in the substrate forming a photosensitive diode junction, and a metal film in rectifying contact with the p-type diffused region to form a Schottky barrier. The method for fabricating the transistor comprises producing the shallow cadmium diffusion, etching the surface of the diffused region to a predetermined depth to reduce the doping level and the surface oxide level, and depositing the metal film on the etched surface of the diffused region.
Inventors
- 👤 Sebastian R. Borrello
- 👤 Jimmy D. Sawyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:12
CPC Classifications
H; H10; H10F; H10F99/00; H10F30/00; H10F30/20; H10F30/21; H10F30/24; H10F30/245; H10F71/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
193 words
A photosensitive semiconductor device comprising: a substrate of n-type semiconductor material, said semiconductor material selected from the group consisting of indium arsenide (InAs), indium antimonide (InSb) and gallium antimonide (GaSb), said substrate being provided with a p-type region defined by diffused cadmium (Cd) in a selected portion thereof and opening onto one surface of said substrate, said p-type region having a surface modified zone, said p-type region cooperating with said n-type substrate to define a photosensitive diode junction therebetween, an insulating layer disposed on said one surface of said substrate and having openings therein in respective registration with said surface modified zone of said p-type region and with a portion of said substrate surface spaced from said surface modified zone of said p-type region, said insulating layer being transparent to light energy, a nonalloyed metal contact member extending through one opening in said insulating layer and in rectifying contact with said surface modified zone of said p-type region to form a Schottky barrier diode junction therewith, and a nonalloyed metal contact member extending through the other opening in said insulating layer and in ohmic contact with said one surface of said n-type substrate.
Claim 2
Dependent Claim
193 words
A photosensitive semiconductor device comprising: a substrate of n-type semiconductor material, said semiconductor material selected from the group consisting of indium arsenide (InAs), indium antimonide (InSb) and gallium antimonide (GaSb), said substrate being provided with a p-type region defined by diffused cadmium (Cd) in a selected portion thereof and opening onto one surface of said substrate, said p-type region having a surface modified zone, said p-type region cooperating with said n-type substrate to define a photosensitive diode junction therebetween, an insulating layer disposed on said one surface of said substrate and having openings therein in respective registration with said surface modified zone of said p-type region and with a portion of said substrate surface spaced from said surface modified zone of said p-type region, said insulating layer being transparent to light energy, a nonalloyed metal contact member extending through one opening in said insulating layer and in rectifying contact with said surface modified zone of said p-type region to form a Schottky barrier diode junction therewith, and a nonalloyed metal contact member extending through the other opening in said insulating layer and in ohmic contact with said one surface of said n-type substrate.
Claim 3
Dependent Claim
18 words
A photosensitive semiconductor device as set forth in claim 1 wherein said nonalloyed metal contact members are aluminum.
Claim 4
Dependent Claim
22 words
A photosensitive semiconductor device as set forth in claim 1 wherein said nonalloyed metal contact members are about 5000 A units thick.
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) | 1980-05-30 | 1980-11-29 | 1981-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-30 | 1984-11-29 | 1985-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-30 | 1988-11-29 | 1989-05-31 | $7700.00 | Window Closed / Lapsed |