US4128843A
Expired / Lapsed
US
⏱️ 0.0 years remaining
GaP Directed field UV photodiode
Assignee: Honeywell Inc
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Filing: 1977-10-14
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Granted: 1978-12-05
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Expires: 1997-10-14
Abstract
Abstract A GaP photodiode having a shallow PN junction and an internal directed surface electric field exhibits high quantum efficiency in detecting ultraviolet wavelengths.
Inventors
- 👤 Alice M. Chiang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:47
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/221; H10F30/2215; H10D; H10D62/00; H10D62/60
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
135 words
An ultraviolet-sensitive photodiode comprising: a GaP body having an ultraviolet radiation receiving surface; an N type region in the GaP body; a P type region in the GaP body proximate the ultraviolet radiation receiving surface and forming a PN junction with the N type region at a depth from the ultraviolet receiving surface of less than about 0.5 microns, the P type region having a graded impurity distribution which decreases essentially monotonically from the ultraviolet radiation receiving surface to the PN junction and creates an internal directed surface electric field of greater than about 10 3 V/cm which repels minority carriers from the ultraviolet radiation receiving surface toward the PN junction; first contact means for providing electrical contact to the N type region; and second contact means providing electrical contact to the P type region.
Claim 2
Dependent Claim
135 words
An ultraviolet-sensitive photodiode comprising: a GaP body having an ultraviolet radiation receiving surface; an N type region in the GaP body; a P type region in the GaP body proximate the ultraviolet radiation receiving surface and forming a PN junction with the N type region at a depth from the ultraviolet receiving surface of less than about 0.5 microns, the P type region having a graded impurity distribution which decreases essentially monotonically from the ultraviolet radiation receiving surface to the PN junction and creates an internal directed surface electric field of greater than about 10 3 V/cm which repels minority carriers from the ultraviolet radiation receiving surface toward the PN junction; first contact means for providing electrical contact to the N type region; and second contact means providing electrical contact to the P type region.
Claim 3
Dependent Claim
23 words
The ultraviolet sensitive photodiode of claim 1 wherein the N type region has a carrier concentration of less than about 10 17 carriers/cm.
Claim 4
Dependent Claim
39 words
The ultraviolet sensitive photodiode of claim 1 and further comprising: bias means connected to the contact means for applying a reverse bias to the PN junction to cause the ultraviolet sensitive photodiode to operate in an avalanche gain mode.
Claim 5
Dependent Claim
95 words
An ultraviolet sensitive photodiode comprising: a GaP body having a first region of first conductivity type and a second region of second conductivity type forming a PN junction in the body, the second region being proximate an ultraviolet radiation receiving surface of the GaP body and having a graded impurity distribution which creates an internal directed surface electric field of greater than about 10 3 V/cm within the second region which repels minority carriers from the ultraviolet radiation receiving surface toward the PN junction; and contact means for deriving a photosignal from the GaP body.
Claim 6
Dependent Claim
95 words
An ultraviolet sensitive photodiode comprising: a GaP body having a first region of first conductivity type and a second region of second conductivity type forming a PN junction in the body, the second region being proximate an ultraviolet radiation receiving surface of the GaP body and having a graded impurity distribution which creates an internal directed surface electric field of greater than about 10 3 V/cm within the second region which repels minority carriers from the ultraviolet radiation receiving surface toward the PN junction; and contact means for deriving a photosignal from the GaP body.
Claim 7
Dependent Claim
16 words
The ultraviolet sensitive photodiode of claim 4 wherein the depth is less than about 0.5 microns.
Claim 8
Dependent Claim
20 words
The ultraviolet sensitive photodiode of claim 5 wherein the graded impurity distribution decreases monotonically from the ultraviolet radiation receiving surface.
Claim 9
Dependent Claim
17 words
The ultraviolet sensitive photodiode of claim 6 wherein the graded impurity distribution is an essentially exponential distribution.
Claim 10
Dependent Claim
23 words
The ultraviolet sensitive photodiode of claim 4 wherein the first conductivity type is N type and the second conductivity type is P type.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-04 | 1982-06-05 | 1982-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-04 | 1986-06-05 | 1986-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-04 | 1990-06-05 | 1990-12-05 | $7700.00 | Window Closed / Lapsed |