Process for forming cone shaped solder for chip interconnection
US6184062A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 19, 1999 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Jan 19, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of forming non-spherically shaped solder interconnects, preferably conical, for attachment of electronic components in an electronic module. Preferably, the solder interconnects of the present invention are cone shaped and comprise of depositing a first solder followed by a second solder having a lower reflow temperature than the first solder. Warm placement of the electronic component at a somewhat elevated temperature than room temperature but less than the solder reflow temperature reduces the force required during placement of a semiconductor chip to a substrate. After warm placement, reflow of the module occurs at the lower reflow temperature of the second solder. The conical shape of the solder interconnects are formed by a heated coining die which may also coin a portion of the interconnects with flat surfaces for stand-offs. The ability of the cone shaped solder interconnects to meet the opposing surface of a chip or substrate at different heights accommodates the camber typically associated with chip and substrate surfaces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.