Pad grid array for receiving a solder bumped chip carrier
US4940181A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 1989 |
| Grant date | Jul 10, 1990 |
| Priority date | — |
| Expiry date | Apr 6, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A pad grid array comprises an array of cavities (12) formed in a circuit carrying substrate (10) that are metallized (18, 20, and 22) to provide electrical conductivity. The metallized cavities are preferably hemispherical in shape and approximately the size of the solder bumps (30) coupled to a solder bumped chip carrier (28) that will be mounted thereon. Flux (26) is applied to each of the metallized cavities before positioning the solder bumped chip (28) carrier over the pad grid array. Proper mounting can be detected by tactile sensing in either human or robotic assemblers when the solder bumps "drop" into the metallized cavities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.