Process for controlling solder joint geometry when surface mounting a leadless integrated circuit package on a substrate
US4878611A · kind A · utility
244Cited by
7References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1988 |
| Grant date | Nov 7, 1989 |
| Priority date | — |
| Expiry date | Jun 9, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A solder joint assembly technique applies controlled volumes of solder to pads of both package and substrate. The two units are positioned adjacent each other with the pads and solder deposits mechanically maintained in registration with each other. The assembly is reflowed and the final separation between package and substrate at which the resulting solder joint solidifies is mechanically controlled in order to control a geometry of the resultant solidified joint. The solder volume deposits may assume various forms including spherical bumps and solder paste deposits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.