Patent US2539994A successfully refreshed from Google Patents.
Patent US4531055A successfully refreshed from Google Patents.
US4531055A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-guarding Schottky barrier infrared detector array
Assignee: United States Department of the Air Force
•
Filing: 1983-01-05
•
Granted: 1985-07-23
•
Expires: 2003-01-05
Abstract
Abstract A two dimensional focal plane array of Schottky photodiodes on a silicon substrate for infrared imaging. The array is designed for mating with multiplexing circuitry and has a self-guarding feature wherein adjacent Schottky electrodes act as guard electrodes. This feature allows a substantial increase of the focal plane area coverage ratio.
Inventors
- 👤 Freeman D. Shepherd, Jr.
- 👤 Paul W. Pellegrini
- 👤 Charlotte E. Ludington
- 👤 Melanie M. Weeks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:20
CPC Classifications
H; H10; H10F; H10F39/00; H10F39/10; H10F39/12; H10F39/18; H10F39/184
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
112 words
A Schottky infrared internal photoemission focal plane array having architecture for maximizing the photosensitive area of said array comprising: a first semiconductor substrate; and a plurality of metallic photoemission elements disposed on a surface of said substrate forming a two dimensional matrix of Schottky barrier photodiodes on said substrate; said Schottky diodes being spaced at a distance within which their individual depletion regions overlap and merge to create a continuous depletion field below the surface of said substrate, thereby suppressing the high fields which occur when depletion region edges are permitted to meet said surface of said substrate, and resulting in the suppression of dark currents and breakdown effects in said array.
Claim 2
Dependent Claim
112 words
A Schottky infrared internal photoemission focal plane array having architecture for maximizing the photosensitive area of said array comprising: a first semiconductor substrate; and a plurality of metallic photoemission elements disposed on a surface of said substrate forming a two dimensional matrix of Schottky barrier photodiodes on said substrate; said Schottky diodes being spaced at a distance within which their individual depletion regions overlap and merge to create a continuous depletion field below the surface of said substrate, thereby suppressing the high fields which occur when depletion region edges are permitted to meet said surface of said substrate, and resulting in the suppression of dark currents and breakdown effects in said array.
Claim 3
Dependent Claim
25 words
A focal plane array as set forth in claim 1 wherein the spacing between adjacent ones of said Schottky diodes does not exceed five micrometers.
Claim 4
Dependent Claim
31 words
A focal plane array as set forth in claim 2 and further comprising: a Schottky perimeter electrode surrounding the matrix of photodiodes and separated by no more than five micrometers therefrom.
Claim 5
Dependent Claim
43 words
A focal plane array as set forth in claim 3 and further comprising: a second semiconductor substrate having signal multiplexing circuitry formed thereon, said second semiconductor substrate being positioned adjacent said first semiconductor substrate and bonded thereto at each of said Schottky photodiodes.
Claim 6
Dependent Claim
22 words
A focal plane array as set forth in claim 4 wherein said first and second substrates are each formed of silicon material.
Claim 7
Dependent Claim
19 words
A focal plane array as set forth in claim 5 wherein said metallic elements are formed of metal silicides.
Claim 8
Dependent Claim
22 words
A focal plane array as set forth in claim 3 and further comprising: a single guard ring surrounding said Schottky perimeter electrode.
References Cited (Backward Citations)
US3821772A
Cited
US4032952A
Cited
US3808435A
Cited
US3902066A
Cited
US4024564A
Cited
US4063964A
Cited
US4379232A
Cited
US4240843A
Cited
US4261095A
Cited
US4290077A
Cited
US4358782A
Cited
US4327291A
Cited
US4471371A
Cited
US4398344A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |