Printed circuit boards with solderable plating finishes and method of making the same
US4572925A · kind A · utility
18Cited by
7References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 13, 1984 |
| Grant date | Feb 25, 1986 |
| Priority date | — |
| Expiry date | Mar 13, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49165
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Printed circuit manufacture may employ a plated palladium-nickel alloy layer as an etch resist and plating finish. Prior to the use of palladium-nickel, tin-lead was used as the etch resist and plating finish. The palladium-nickel layer is generally superior to the corresponding tin-lead layer except for solderability. To improve the solderability of at least these areas of the palladium-nickel to which elements are to be soldered, a layer of copper is deposited thereon. If desired, the solderability of the copper may be preserved by coating it with, for example, a tin-lead layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.