Metal ball grid electronic package having improved solder joint
US5952719A · kind A · utility
10Cited by
28References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 10, 1997 |
| Grant date | Sep 14, 1999 |
| Priority date | — |
| Expiry date | Jul 10, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The bending of a ball grid array electronic package having a metallic base is reduced minimizing stresses applied to the innermost row of solder balls when the package base is cyclically heated and cooled. Reducing the stresses applied to the solder balls increases the number of thermal cycles before solder ball fracture causes device failure. Among the means disclosed to reduce the bending moment are a bimetallic composite base, an integral stiffener, a centrally disposed cover bonded to an external structure and a package base with a stress accommodating depressed portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.