US4227036A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite flanged ceramic package for electronic devices
Assignee: STMicroelectronics lnc USA
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Filing: 1978-09-18
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Granted: 1980-10-07
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Expires: 1998-09-18
Abstract
Abstract An improved ceramic-based package for electronic devices having a composite flange for heat dissipation comprising a layer of heat conducting metal having a thermal coefficient of expansion appreciably different from that of the base secured to the base and a second layer of metal secured to the first layer having a thermal coefficient of expansion approximately equal to that of the ceramic. In a preferred embodiment, the first layer is copper, and the second is molybdenum.
Inventors
- 👤 William Fitzgerald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:22
CPC Classifications
H; H10; H10W; H10W76/00; H10W76/10; H10W76/12; H10W76/15; H10W76/157; H10W40/00; H10W40/10; H10W40/20; H10W40/25; H10W40/255; H10W76/17; H10W76/18; Y; Y10; Y10T; Y10T403/00; Y10T403/21; Y10T403/217
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
101 words
In a package for electronic devices of the type comprising a heat conducting ceramic base member and a metal flange secured to said base for dissipating heat from said base, the improvement wherein said flange comprises a bi-layer composite bi-metallic flange comprising a first layer of heat conducting metal having a thermal conductivity and a thermal coefficient of expansion appreciably greater than that of said base and, on the side of said first layer opposite said ceramic base, a second layer of metal secured to said first layer having a thermal coefficient of expansion approximately equal to that of the ceramic.
Claim 2
Dependent Claim
101 words
In a package for electronic devices of the type comprising a heat conducting ceramic base member and a metal flange secured to said base for dissipating heat from said base, the improvement wherein said flange comprises a bi-layer composite bi-metallic flange comprising a first layer of heat conducting metal having a thermal conductivity and a thermal coefficient of expansion appreciably greater than that of said base and, on the side of said first layer opposite said ceramic base, a second layer of metal secured to said first layer having a thermal coefficient of expansion approximately equal to that of the ceramic.
Claim 3
Dependent Claim
27 words
A package according to claim 1 wherein said first layer comprises a metal having a thermal coefficient of expansion exceeding that of the ceramic by about 100%.
Claim 4
Dependent Claim
12 words
A package according to claim 1 wherein said first layer is copper.
Claim 5
Dependent Claim
29 words
A package according to claim 1 wherein said second layer of metal has a thermal coefficient of expansion within the range of 70% to 130% that of the ceramic.
Claim 6
Dependent Claim
29 words
A package according to claim 1 wherein said second layer comprises a metal selected from the group consisting of molybdenum, tungsten and an alloy of nickel, cobalt and iron.
Claim 7
Dependent Claim
20 words
A package according to claim 1 wherein said ceramic is beryllium oxide and said second layer of metal is molybdenum.
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) | 1983-10-07 | 1984-04-07 | 1984-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-07 | 1988-04-07 | 1988-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-07 | 1992-04-07 | 1992-10-07 | $7700.00 | Window Closed / Lapsed |