US3669907A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductive elements
Assignee: Panasonic Holdings Corp
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Filing: 1967-12-01
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Granted: 1972-06-13
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Expires: 1987-12-01
Abstract
Abstract Semiconductive elements having a specific resistivity of the semiconductor range (that is, 105 to 108 ohm-cm) which have an ohmic resistance even in an considerably high electric field and are highly durable in adverse physical and atmospheric conditions, which are manufactured by heating a mixture of powder of vitreous binding material and powder of semiconductive metal oxide dispersed in the former powder. Further, the dielectric strength and the uniformity of resistivity of said semiconductive elements can be improved by adding, to the mixture, powder of an oxide whose conductivity is much higher than that of said semiconductive metal oxide.
Inventors
- 👤 Tadao Kohashi
- 👤 Kazunobu Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:06
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/06; H01C17/065; H01C17/06506; H01C17/06513; H01C17/06533; H01B; H01B1/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
170 words
A method for manufacturing a semiconductive element having particles of pulverized semiconductive metal oxide dispersed in a vitreous binding material, comprising the steps of mixing pulverized glass, whose average grain size is smaller than 1 micron, with a powder of at least one semiconductive metal oxide selected from the group consisting of SnO2, TiO2, WO3, Sb2O5, Cr2O3, Fe2O3, V2O5 and Bi2O3, whose average grain size is smaller than 5 microns but larger than the grain size of said glass, the amount of said metal oxide being 10 to 35 percent in volume; stirring the mixture with a volatile liquid additive until the mixture acquires a sol-like state; applying said mixture in the form of a layer on the surface of a heat-resistive substrate whose softening point is higher than the softening point of said glass; and heating said layer of mixture at a temperature higher than the softening point of said glass but lower than the softening point of said heat-resistive substrate, to thereby adhere said layer to said substrate.
Claim 2
Independent Claim
125 words
A method for manufacturing a semiconductive element having particles of pulverized semiconductive metal oxide and of pulverized oxide whose specific resistivity is higher than that of a semiconductive metal oxide dispersed in a vitreous binding material comprising the steps of mixing powder of glass with powder of at least one semiconductive metal oxide selected from the group consisting of SnO2, TiO2, WO3, Sb2O5, Cr2O3, Fe2O3, V2O5 and Bi2O3 and powder of an oxide whose specific resistivity is higher than that of said semiconductive metal oxide, the grain size of said metal oxide powder and said oxide powder being larger than that of said glass powder, and particles of said metal oxide and said oxide being well dispersed in said glass powder, and heating the mixture.
Claim 3
Independent Claim
181 words
A method for manufacturing a semiconductive element having particles of pulverized semiconductive metal oxide and of pulverized oxide whose specific resistivity is higher than that of a semiconductive metal oxide dispersed in a vitreous binding material comprising the steps of mixing pulverized glass, whose average grain size is smaller than 1 micron, with powder of at least one semiconductive metal oxide selected from the group consisting of SnO2, TiO2, WO3, Sb2O5, Cr2O3, Fe2O3, V2O5 and Bi2O3 and pulverized oxide, whose specific resistivity is higher than that of said metal oxide, the average grain size of said metal oxide and said oxide being smaller than 5 microns but larger than that of said glass, and the amount of said metal Oxide being 10 to 35 percent in volume; stirring the mixture with a volatile liquid additive until said mixture acquires a sol-like state; applying said mixture in the form of a layer on the surface of a heat-resistive substrate whose softening point is higher but lower than the softening point of said heat-resistive substrate to thereby adhere said layer to said substrate.
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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) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |