Printed circuit board manufacture
US6860925B2 · kind B2 · utility
24Cited by
20References
31Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2002 |
| Grant date | Mar 1, 2005 |
| Priority date | — |
| Expiry date | Apr 23, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49144
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A process used during manufacture of printed circuit boards comprises protecting metal pads and/or through-holes to provide a tarnish-resistant and solderable coating. In the method, the pads and/or through-holes are bright-etched, metal plated, preferably by an immersion process, and treated with a tarnish inhibitor. The tarnish inhibitor may be incorporated into the immersion plating bath. The metal plating is usually with silver or bismuth and the pads and/or through-holes comprise copper.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.