US3971057A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lateral photodetector of improved sensitivity
Assignee: United States Department of the Navy
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Filing: 1973-08-21
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Granted: 1976-07-20
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Expires: 1993-08-21
Abstract
Abstract A lateral photodetector of improved sensitivity and method of making the e. The photodetector consists of semiconductive wafer, having a transparent layer of metal deposited on its front face to form a Schottky barrier. A negative bias is applied to the Schottky barrier to form a depletion region in the wafer. A low resistivity layer is formed on back of the wafer to which four signal electrodes are attached. Before forming the cell, the semiconductor wafer was exposed to nuclear radiation to increase the responsivity of the cell.
Inventors
- 👤 William P. Connors
- 👤 Richard H. Glaenzer
- 👤 George A. Saum
- 👤 Robert G. Wagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:52
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/227; H10F77/00; H10F77/20; H10F77/206; H10F77/244; H10F77/254; H10F77/95; H10F77/953; H10F77/957; Y; Y10; Y10S; Y10S438/00; Y10S438/98
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
77 words
In the process of making a lateral photodetector including the steps of applying a Schottky barrier to one face of a semiconductor wafer, connecting a lead wire to the Schottky barrier, and connecting four electrodes to the opposite face of said wafer, the improvement comprising: lowering, isotropically, the lateral resistivity of the opposite face of the semiconductor wafer; and exposing said wafer to a source of nuclear radiation for a predetermined period before applying the Schottky barrier.
Claim 2
Dependent Claim
77 words
In the process of making a lateral photodetector including the steps of applying a Schottky barrier to one face of a semiconductor wafer, connecting a lead wire to the Schottky barrier, and connecting four electrodes to the opposite face of said wafer, the improvement comprising: lowering, isotropically, the lateral resistivity of the opposite face of the semiconductor wafer; and exposing said wafer to a source of nuclear radiation for a predetermined period before applying the Schottky barrier.
Claim 3
Dependent Claim
27 words
The process of claim 1 wherein the step of lowering the resistivity of the opposite face comprises diffusing a conductive layer of material on the opposite face.
Claim 4
Dependent Claim
18 words
The process of claim 2 wherein the semiconductor wafer is n-type silicon and the conductive layer is phosphorous-doped.
Claim 5
Dependent Claim
25 words
The process of claim 1 wherein the step of lowering the resistivity of the opposite face comprises evaporating a resistive-metal sheet onto said opposite face.
Claim 6
Dependent Claim
25 words
The process of claim 1 wherein the step of lowering the resistivity of the opposite face comprises depositing an epitaxial layer on said opposite face.
Claim 7
Dependent Claim
40 words
The process of claim 1 wherein the step of lowering the resistivity of the opposite face comprises applying a bias voltage to the lead wire to create a depletion region in the wafer that is spaced from said opposite face.
Claim 8
Dependent Claim
27 words
The process of claim 6 wherein the wafer is n-type silicon with a resistivity of 1000 to 2000 ohm-cm and a thickness of 0.060 to 0.070 inches.
Claim 9
Dependent Claim
11 words
The process of claim 1 wherein the wafer is n-type silicon.
Claim 10
Dependent Claim
86 words
A lateral photodetector comprising: an n-type silicon semiconductor wafer; a Schottky barrier on one face of the wafer; a lead wire connected to the Schottky barrier for applying a negative bias to the barrier and creating a depletion region in the wafer; a low resistivity layer of an evaporated, resistive-metal sheet on the other face of said wafer, the lateral resistivity of said layer being isotropic, said metal selected from the group consisting of nichrome and chromium; and four electrodes connected to said low resistivity layer.
Claim 11
Dependent Claim
86 words
A lateral photodetector comprising: an n-type silicon semiconductor wafer; a Schottky barrier on one face of the wafer; a lead wire connected to the Schottky barrier for applying a negative bias to the barrier and creating a depletion region in the wafer; a low resistivity layer of an evaporated, resistive-metal sheet on the other face of said wafer, the lateral resistivity of said layer being isotropic, said metal selected from the group consisting of nichrome and chromium; and four electrodes connected to said low resistivity layer.
References Cited (Backward Citations)
US3207902A
Cited
US3615929A
Cited
US3548213A
Cited
US3502884A
Cited
US3582654A
Cited
US3667116A
Cited
US3700978A
Cited
US3704376A
Cited
US3775191A
Cited
US3761711A
Cited
US3792257A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-20 | 1980-01-19 | 1980-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-20 | 1984-01-19 | 1984-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-20 | 1988-01-19 | 1988-07-20 | $7700.00 | Window Closed / Lapsed |