Tin-indium based low temperature solder alloy
US9741676B1 · kind B1 · utility
2Cited by
2References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2016 |
| Grant date | Aug 22, 2017 |
| Priority date | — |
| Expiry date | Jun 24, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3511
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lead-free solder alloy having a low melting temperature and low yield strength is disclosed. The solder alloy includes 5.0-20.0 wt. % of indium (In), 1.0-5.0 wt. % of silver (Ag), 0.25-2.0 wt. % of copper (Cu), 0.1-0.5 wt. % of zinc (Zn), and a remainder of tin (Sn). In implementations, a sulfur compound may be included in a concentration of 100 ppm to 500 ppm in the alloy to prevent oxidation of zinc and indium on the surface of the alloy. The solder alloy is particularly useful for but not limited to solder on pad applications in first level interconnect semiconductor device packaging.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.