Method of forming a metal layer and method of manufacturing a substrate having such metal layer
US9988730B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2015 |
| Grant date | Jun 5, 2018 |
| Priority date | — |
| Expiry date | Mar 12, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0796
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a substrate like a printed circuit board comprising an insulator and a copper layer laminated on part of the insulator, said insulator outer surface and said copper layer outer surface are simultaneously subjected to a process (1) comprising treatment with an alkali metal hydroxide solution, a process (2) comprising treatment with an alkaline aqueous solution containing an aliphatic amine, a process (3) comprising treatment with an alkaline aqueous solution having a permanganate concentration of 0.3 to 3.5 wt % and a pH of 8 to 11, a process (4) comprising treatment with an acidic microemulsion aqueous solution containing a thiophene compound and an alkali metal salt of polystyrenesulphonic acid, and a process (5) comprising copper electroplating, which are implemented sequentially.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.