US3925698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Colloidal semiconductor and method of manufacture
Assignee: United States Department of the Army
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Filing: 1973-10-12
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Granted: 1975-12-09
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Expires: 1993-10-12
Abstract
Abstract A photoemissive cathode is provided consisting of colloidal semiconducting material on a base transparent to visible and/or infrared radiation. The semiconductor material may be a binary or ternary compound from the groups III-V or II-VI of the periodic table. The semiconducting colloids are formed by a simultaneous precipitation and doping process.
Inventors
- 👤 Herbert A Stahl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:44
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/34; H01J2201/00; H01J2201/34; H01J2201/342; H01J2201/3421; H01J2201/3423
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
69 words
A PHOTOCATHODE COMPRISING: A TRANSPARENT WINDOW PLATE; AND A BASE LAYER ON SAID PLATE OF PHOTOEMISSIELY ACTIVE SEMICONDUCTOR MATERIAL CONSISTING OF INDIVIDUAL, COLLOIDIAL PARTICLES DEPOSITED BY THE EVAPORATION OF THEIR SUSPENSION MEDIUM, SAID PARTICLES BEING UNDER 100 MILLIMICRONS IN SIZE AND FORMED OF COMPOUNDS FROM A GROUP CONSISTING OF ELEMENTS FROM COLUMNS III AND V, OR II AND VI, OF THE PERIODIC SYSTEM OF ELEMENTS CONTAINING A P-TYPE DOPANT.
Claim 2
Dependent Claim
69 words
A PHOTOCATHODE COMPRISING: A TRANSPARENT WINDOW PLATE; AND A BASE LAYER ON SAID PLATE OF PHOTOEMISSIELY ACTIVE SEMICONDUCTOR MATERIAL CONSISTING OF INDIVIDUAL, COLLOIDIAL PARTICLES DEPOSITED BY THE EVAPORATION OF THEIR SUSPENSION MEDIUM, SAID PARTICLES BEING UNDER 100 MILLIMICRONS IN SIZE AND FORMED OF COMPOUNDS FROM A GROUP CONSISTING OF ELEMENTS FROM COLUMNS III AND V, OR II AND VI, OF THE PERIODIC SYSTEM OF ELEMENTS CONTAINING A P-TYPE DOPANT.
Claim 3
Dependent Claim
26 words
A photocathode according to claim 1 wherein: said colloidal semiconductor material is doped with an additional element from Groups I through III of the periodic system.
Claim 4
Dependent Claim
58 words
A photocathode comprising: a transparent window plate; and a base layer deposited on said plate of photoemissively active semiconductor material consisting of individual, colloidal particles deposited by the evaporation of their suspension medium, said particles being under 100 millimicrons in size and formed of elements from column IV of the periodic system of elements containing a p-type dopant.
Claim 5
Dependent Claim
58 words
A photocathode comprising: a transparent window plate; and a base layer deposited on said plate of photoemissively active semiconductor material consisting of individual, colloidal particles deposited by the evaporation of their suspension medium, said particles being under 100 millimicrons in size and formed of elements from column IV of the periodic system of elements containing a p-type dopant.
Claim 6
Dependent Claim
21 words
A photocathode according to claim 3 wherein: said dopant is an element from Groups I through III of the periodic system.
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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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |