Solder process and solder alloy therefor
US6619536B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 2003 |
| Grant date | Sep 16, 2003 |
| Priority date | — |
| Expiry date | Mar 5, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/14
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A solder alloy containing indium, lead, silver and copper as its alloying constituents, and a soldering process employing the solder alloy. The solder alloy consists essentially of, by weight, about 50% to about 65% indium, about 0.5% to about 3.0% silver, up to about 3.0% copper, the balance lead and incidental impurities. The alloy preferably has a solidus temperature in a range of about 173° C. to about 178° C., and a liquidus temperature in a range of about 187° C. to about 196° C. As such, the alloy can be used in a reflow process with a peak reflow temperature of about 220° C. to about 240° C., and is therefore compatible with most circuit components and can be simultaneously reflowed with 63Sn-37Pb solder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.