US3813541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mos photodiode
Assignee: COLUMBIA BROADCASTING SYS Inc
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Filing: 1973-08-02
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Granted: 1974-05-28
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Expires: 1993-08-02
Abstract
Abstract A photodetector which comprises an MOS structure having a very small non-obscuring front contact, in the form of a dot or ring, plus the usual ohmic contact to the semi-conductor body. The device is adapted to be reverse-biased to give a wide depletion range, and an inversion layer at the semiconductor-insulator interface conducts electrons along the surface from the point of generation by absorption of photons to the region of the front contact. The device has a relatively large light-sensitive area, exhibits fast response time, and has a spectral characteristic of high quantum efficiency over the range of about 0.2 to 1.1 microns wavelength.
Inventors
- 👤 N Foss
- 👤 S Ward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:39
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/28; H10F30/2823
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
157 words
Apparatus for detecting light comprising in combination: A. a photodiode including: a. a semiconductor body of one conductivity type having a surface region of opposite conductivity type, said surface region constituting an inversion layer which is more highly conductive than said body of semiconductor material; b. a dielectric film deposited over said region, said film being substantially transparent to light; c. a single metal electrode on said film, said electrode being sufficiently small in area to leave a substantial portion of said film exposed; d. a separate low resistance electrode connection to the opposite surface of semiconductor body and B. circuit means including a source of direct current potential and a resistor connected in series between said single metal electrode and said separate low resistance electrode, said source of potential being poled to reverse bias said photodiode, said resistor having a continuous current flow therethrough which reflects the degree of illumination, if any, of said dielectric film.
Claim 2
Dependent Claim
157 words
Apparatus for detecting light comprising in combination: A. a photodiode including: a. a semiconductor body of one conductivity type having a surface region of opposite conductivity type, said surface region constituting an inversion layer which is more highly conductive than said body of semiconductor material; b. a dielectric film deposited over said region, said film being substantially transparent to light; c. a single metal electrode on said film, said electrode being sufficiently small in area to leave a substantial portion of said film exposed; d. a separate low resistance electrode connection to the opposite surface of semiconductor body and B. circuit means including a source of direct current potential and a resistor connected in series between said single metal electrode and said separate low resistance electrode, said source of potential being poled to reverse bias said photodiode, said resistor having a continuous current flow therethrough which reflects the degree of illumination, if any, of said dielectric film.
Claim 3
Dependent Claim
23 words
Apparatus in accordance with claim 1 wherein said surface inversion layer has a sheet resistance of the order of 100 ohms per square.
Claim 4
Dependent Claim
18 words
Apparatus in accordance with claim 1 wherein said single metal electrode is in the form of a ring.
Claim 5
Dependent Claim
19 words
Apparatus in accordance with claim 1 wherein said single metal electrode is in the form of a metal dot.
References Cited (Backward Citations)
US3353114A
Cited
US3562425A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |