Apparatus and method for injection molding solder and applications thereof
US5244143A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1992 |
| Grant date | Sep 14, 1993 |
| Priority date | — |
| Expiry date | Apr 16, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/128
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An apparatus and method are described for injection molding solder mounds onto electronic devices. The apparatus has a reservoir for molten solder which is disposed over a cavity in an injection plate. The injection plate is disposed over a mold having an array of cavities therein into which solder in injection molded. The mold is disposed over a workpiece, such as a semiconductor chip or a semiconductor chip packaging substrate. The cavities in the mold are aligned with electrical contact locations on the chip or substrate. The workpiece is heated and the molten solder is forced under gas pressure into the cavity in the injection plate disposed above the array of cavities in the mold. The molten solder is forced into the array of cavities in the mold. The injection plate is advanced to slide over the mold to wipe away the excess solder above the mold at a plurality of wiping apertures in the injection plate. The injection plate is further advanced to a location having a nonsolder wettable surface at which location the injection plate is removed. The mold is then removed to leave solder mounds disposed on the workpiece. The workpiece can be a semiconductor chip, a semiconductor chi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.