Microwave integrated circuit package to eliminate alumina substrate cracking and method
US5102029A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1990 |
| Grant date | Apr 7, 1992 |
| Priority date | — |
| Expiry date | Jun 22, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3011
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A MIC package housing that reduces or completely eliminates alumina substrate cracking due to thermal expansion rate differences between the housing and the alumina by using a low-expansion iron-nickel alloy, such as commercially available Carpenter 49, made to ASTM Specification A-753-78 (Alloy 2) and MIL-N-14411B (MR) (Composition 3 and 4). Such a housing places compressive stresses on glass-to-metal seals used in hermetic feedthroughs and the glass is fused and the stresses relieved by a special process of annealing. Manufacturing yields are improved and very large alumina substrates can be used and are attached by hard soldering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.