US3933668A
Expired / Lapsed
US
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Intergranular insulation type polycrystalline ceramic semiconductive composition
Assignee: Sony Corp
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Filing: 1974-07-10
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Granted: 1976-01-20
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Expires: 1994-07-10
Abstract
Abstract An intergranular insulation type semiconductive ceramic composition comprising a major proportion of strontium titanate (SrTiO3), a minor amount of niobium oxide (Nb2O5) or tantalum oxide (Ta2O5), a minor amount of either germanium oxide (GeO2) or zinc oxide (ZnO) and having diffused therein either bismuth oxide (Bi2O3) or a mixture of bismuth oxide, lead oxide (PbO) and boric oxide (B2O3). The material is especially useful as a capacitor.
Inventors
- 👤 Yasunori Takahashi
- 👤 Nobutatsu Yamaoka
- 👤 Yoshifumi Yamaoka
- 👤 Shuichi Kakubari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:49
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/06; H01G4/08; H01G4/12; H01G4/1272; H01G4/1281; C; C04; C04B; C04B35/00; C04B35/01; C04B35/46; C04B35/462; C04B35/465; C04B35/47
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
93 words
An intergranular insulation type semiconductive ceramic composition comprising from 90.68 to 99.88% by weight of polycrystalline SrTiO 3 , from 0.07 to 5.32% by weight of either Nb 2 O 5 or Ta 2 O 5 , from 0.05 to 4.00% by weight of either GeO 2 or ZnO, and having diffused therein either Bi 2 O 3 or a mixture of Bi 2 O 3 , PbO, and B 2 O 3 , the diffused material providing a substantially uniform insulating layer about the grain boundaries of the polycrystalline SrTiO 3 .
Claim 2
Dependent Claim
93 words
An intergranular insulation type semiconductive ceramic composition comprising from 90.68 to 99.88% by weight of polycrystalline SrTiO 3 , from 0.07 to 5.32% by weight of either Nb 2 O 5 or Ta 2 O 5 , from 0.05 to 4.00% by weight of either GeO 2 or ZnO, and having diffused therein either Bi 2 O 3 or a mixture of Bi 2 O 3 , PbO, and B 2 O 3 , the diffused material providing a substantially uniform insulating layer about the grain boundaries of the polycrystalline SrTiO 3 .
Claim 3
Dependent Claim
69 words
The composition of claim 1, which contains from 90.68 to 99.88 percent by weight SrTiO 2 , from 0.07 to 5.32 percent by weight Nb 2 O 5 , from 0.05 to 4.00 percent by weight GeO 2 and the diffused oxides contain 32 to 53 weight percent PbO, 37 to 64 weight percent Bi 2 O 3 and 2 to 10 weight percent B 2 O 3 .
Claim 4
Dependent Claim
71 words
The composition of claim 1, which contains from 91.92 to 99.62 percent by weight SrTiO 3 , from 0.33 to 4.08 percent by weight Ta 2 O 5 , from 0.05 to 4.00 percent by weight GeO 2 and the diffused oxides contain from 17 to 58 weight percent PbO, from 34 to 63 weight percent Bi 2 O 3 and 2 to 10 weight percent B 2 O 3 .
Claim 5
Dependent Claim
68 words
The composition of claim 1, which contains from 91.18 to 99.82 percent by weight SrTiO 3 , from 0.13 to 5.32 percent by weight Nb 2 O 5 , from 0.05 to 3.5 weight percent ZnO and the diffused oxides contain from 29 to 63 weight percent PbO, 35 to 65 weight percent Bi 2 O 3 and 2 to 10 weight percent B 2 O 3 .
Claim 6
Independent Claim
92 words
A method of making an intergranular insulation type semiconductor ceramic composition which comprises mixing a major amount of SrTiO 3 with a minor amount of Nb 2 O 5 or Ta 2 O 5 and a minor amount of GeO 2 or ZnO, molding the resulting mixture and sintering the same in a slightly reducing atmosphere to produce a polycrystalline ceramic, and thereafter diffusing therein Bi 2 O 3 or a mixture of Bi 2 O 3 , PbO, and B 2 O 3 to insulate the grain boundaries of said ceramic.
Claim 7
Independent Claim
92 words
A method of making an intergranular insulation type semiconductor ceramic composition which comprises mixing a major amount of SrTiO 3 with a minor amount of Nb 2 O 5 or Ta 2 O 5 and a minor amount of GeO 2 or ZnO, molding the resulting mixture and sintering the same in a slightly reducing atmosphere to produce a polycrystalline ceramic, and thereafter diffusing therein Bi 2 O 3 or a mixture of Bi 2 O 3 , PbO, and B 2 O 3 to insulate the grain boundaries of said ceramic.
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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) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |