Electroless copper composition solution using a hypophosphite reducing agent
US4209331A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 1978 |
| Grant date | Jun 24, 1980 |
| Priority date | — |
| Expiry date | May 25, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C18/40
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Electroless copper deposition solutions, and method of electrolessly depositing copper onto a workpiece using these solutions, are disclosed. The solutions contain, in addition to water as the usual solvent, a soluble source of copper ions, a complexing agent or mixture of agents to maintain the copper in solution, and a copper reducing agent effective to reduce the copper ions to metallic copper as a deposit or plating on a prepared surface of a workpiece brought into contact with the solution. The invention comprehends replacing the usual formaldehyde-type reducing agents of commercial electroless copper baths with non-formaldehyde-type agents, specifically hypophosphites, by coordinating the particular complexing agents employed and the bath pH, to effect reduction of cupric ions to a metallic copper plating on a prepared surface of a substrate, wherein the resulting electroless metal deposit has conductive properties at least satisfactory for build-up of additional thickness of metal by standard electroplating techniques. Improvement over the prior formaldehyde-reduced electroless copper solutions is obtained in that the invention teaches those skilled in the art how to achieve…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.