Modeling technique for selectively depopulating electrical contacts from a foot print of a grid array (BGA or LGA) package to increase device reliability
US6689634B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 1999 |
| Grant date | Feb 10, 2004 |
| Priority date | — |
| Expiry date | Sep 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/10734
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A modeling technique for selectively depopulating solder balls (12) (and their respective solder ball pads (34), vias (32) and traces or lines (30)) from a conventional foot print of a ball grid array (BGA) package, or land grid array package (LGA) to improve device reliability. The modeling technique anticipates a routing of traces through the gap resulting from the depopulated solder balls or lands as additional space for routing traces or lines from solder ball or land pads to an exterior surface of a substrate (14) upon which a semiconductor die (20) is mounted. An advantage of the present invention is that it permits the retention of an optimum via diameter while increasing the number of solder balls or lands on ever shrinking packages, thereby increasing device reliability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.