US4649409A
Expired / Lapsed
US
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Photoelectric transducer element
Assignee: Toshiba Corp
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Filing: 1983-10-19
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Granted: 1987-03-10
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Expires: 2003-10-19
Abstract
Abstract A photoelectric transducer element is disclosed wherein a region having a conductivity type opposite to that of a light-receiving region is formed in a surface layer of the light-receiving region of a photoelectric transducer element having a p-n junction. The switching speed of the element can be improved without decreasing either the photosensitivity or dielectric withstand voltage.
Inventors
- 👤 Makoto Roppongi
- 👤 Kazuaki Tsuji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:27
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/24; H10F30/245
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
106 words
A phototransistor comprising: a semiconductor substrate of a first conductivity type constituting a collector region: a base region of a second conductivity type formed in said semiconductor substrate and having a surface area, said base region constituting a light receiving region; an emitter region of said first conductivity type formed in said base region and having a surface area; a floating potential region of said first conductivity type formed in the surface layer of said base region; a collector electrode provided on said semiconductor substrate constituting a collector region; a base electrode provided on said base region; and an emitter electrode provided on said emitter region.
Claim 2
Dependent Claim
106 words
A phototransistor comprising: a semiconductor substrate of a first conductivity type constituting a collector region: a base region of a second conductivity type formed in said semiconductor substrate and having a surface area, said base region constituting a light receiving region; an emitter region of said first conductivity type formed in said base region and having a surface area; a floating potential region of said first conductivity type formed in the surface layer of said base region; a collector electrode provided on said semiconductor substrate constituting a collector region; a base electrode provided on said base region; and an emitter electrode provided on said emitter region.
Claim 3
Dependent Claim
28 words
A phototransistor according to claim 1, wherein said surface area of said base region is at least twice as large as said surface area of said emitter region.
Claim 4
Dependent Claim
19 words
A phototransistor according to claim 1, wherein said floating potential region is formed in part of said base region.
Claim 5
Dependent Claim
21 words
A phototransistor according to claim 1, wherein said floating potential region is formed over the entire region of said base region.
Claim 6
Dependent Claim
15 words
A phototransistor according to claim 1, wherein said floating potential region contacts said base region.
References Cited (Backward Citations)
DE2656420A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-03-09 | 1990-09-08 | 1991-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-09 | 1994-09-08 | 1995-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-09 | 1998-09-08 | 1999-03-10 | $7700.00 | Window Closed / Lapsed |