Solder ball with chemically and mechanically enhanced surface properties
US6607613B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 2001 |
| Grant date | Aug 19, 2003 |
| Priority date | — |
| Expiry date | May 3, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12687
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A metal alloy solder ball comprising a first metal and a second metal, the first metal having a sputtering yield greater than the second metal. The solder ball comprises a bulk portion having a bulk ratio of the first metal to the second metal, an outer surface, and a surface gradient having a depth and a gradient ratio of the first metal to the second metal that is less than the bulk ratio. The gradient ratio increases along the surface gradient depth from a minimum at the outer surface. The solder ball may be formed by the process of exposing the ball to energized ions of a sputtering gas for an effective amount of time to form the surface gradient.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.