Device mounting
US4995546A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 18, 1989 |
| Grant date | Feb 26, 1991 |
| Priority date | — |
| Expiry date | Oct 18, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/0237
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A technique for assembling semiconductor devices in which semiconductor elements, especially lasers or LEDs, are mounted on a first packaging element such as a heat spreader that is mounted on a second packaging element such as a heat sink. Handling of solder preforms is avoided by coating at least one of each of the pairs of surfaces to be brought into contact with a layer of solder and heating the assembly to melt both solder layers in a single operation. In a preferred embodiment a heat spreader is coated in solder on both sides and interposed between a semiconductor element and a heat sink and the assembly is heated. Molybdenum may be used as a layer to aid wetting and adhesion and gold/tin solder may be used. Slightly different solidification temperatures and compositons for the layers may result from different take up of metallization layers from the components into the solder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.