Flexible core for enhancement of package interconnect reliability
US7352061B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2005 |
| Grant date | Apr 1, 2008 |
| Priority date | — |
| Expiry date | May 20, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/068
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An IC package is disclosed that comprises a core region disposed between upper and lower build-up layer regions. In one embodiment, the core region comprises a low modulus material. In an alternative embodiment the core region comprises a medium modulus material. In an alternative embodiment, the core material is selected based upon considerations such as its modulus, its coefficient of thermal expansion, and/or the resulting total accumulated strain. In an alternative embodiment, boundaries with respect to the softness of the core material are established by considering the relative density in opposing conductive build-up layers above and below the core region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.