Process for synthesizing a palladium replenisher for electroplating baths
US6346222B1 · kind B1 · utility
4Cited by
5References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1999 |
| Grant date | Feb 12, 2002 |
| Priority date | — |
| Expiry date | Jun 1, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
This invention provides a process of making a palladium replenisher comprising a complex of palladium tetraammine sulfate. The process includes distilling a palladium nitrate solution at a temperature maintained at or below about 115° C. Palladium sulfate and ammonium hydroxide are then added to make the palladium tetraamine sulfate replenisher from solution. The replenisher of the invention is used to replenish depleted palladium during palladium electroplating to maintain the palladium concentration in the bath within from about 5 to about 10 weight percent of recommended plating bath levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.