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US4883704A
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Circuit substrate comprising nitride type ceramics, method for preparing it, and metallizing composition for use in it
Assignee: Toshiba Corp
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Filing: 1988-03-29
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Granted: 1989-11-28
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Expires: 2008-03-29
Abstract
Abstract One aspect of the present invention is directed to an aluminum nitride ceramic substrate which comprises an aluminum nitride ceramic sheet and a conductive metallized layer formed thereon. The metallized layer comprises molybdenum and/or tungsten and contains a compound containing yttria and alumina in the vicinity of the interface between the aluminum nitride ceramic sintered sheet and the conductive metallized layer.
Inventors
- 👤 Hideki Sato
- 👤 Nobuyuki Mizunoya
- 👤 Hironori Asai
- 👤 Kazuo Anzai
- 👤 Tsuyoshi Hatano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:14
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/515; C04B35/58; C04B35/581; C04B41/45; C04B41/50; C04B41/51; C04B41/5133; C04B41/52; C04B41/80; C04B41/81; C04B41/85; C04B41/88; C04B41/89; H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H10W70/098; H10W70/60; H10W70/62; H10W70/66; H10W70/67; H10W70/69; H10W70/692; C04B2111/00; C04B2111/00474; C04B2111/00844; H05K1/09; H05K1/092; H05K3/00; H05K3/38; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/24926
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
65 words
An aluminum nitride ceramic substrate comprising: an aluminum nitride ceramic sintered sheet; a conductive metallized layer comprising at least one of the group consisting of molybdenum and tungsten formed on said aluminum nitride ceramic sintered sheet; and a layer of a compound containing yttria and alumina at the interface between said aluminum nitride ceramic sintered sheet and said metallized layer and penetrating the metallized layer.
Claim 2
Dependent Claim
65 words
An aluminum nitride ceramic substrate comprising: an aluminum nitride ceramic sintered sheet; a conductive metallized layer comprising at least one of the group consisting of molybdenum and tungsten formed on said aluminum nitride ceramic sintered sheet; and a layer of a compound containing yttria and alumina at the interface between said aluminum nitride ceramic sintered sheet and said metallized layer and penetrating the metallized layer.
Claim 3
Dependent Claim
22 words
An aluminum nitride ceramic substrsate according to claim 1 wherein said compound containing yttria and alumina is uniformly distributed at the interface.
Claim 4
Dependent Claim
28 words
An aluminum nitride substrate according to claim 1 wherein said compound of yttria and alumina further penetrates said aluminum nitride sheet at the interface with said metallized layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-11-27 | 1993-05-29 | 1993-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-27 | 1997-05-29 | 1997-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-27 | 2001-05-29 | 2001-11-28 | $7700.00 | Window Closed / Lapsed |