Liquid etchant and method for roughening copper surface
US6666987B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 1999 |
| Grant date | Dec 23, 2003 |
| Priority date | — |
| Expiry date | Jun 8, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/124
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A liquid etchant and a method for roughening a copper surface each capable of providing copper with a roughened surface increased in acid resistance regardless of a chlorine ion in a short period of time, to thereby ensure firm adhesion between a copper conductive pattern and an outer layer material during manufacturing of a printed circuit board, resulting in the manufacturing being highly simplified. The liquid etchant includes a main component containing an oxo acid such as sulfuric acid and a peroxide such as hydrogen peroxide. Also, the liquid etchant includes an auxiliary component containing a tetrazole such as 5-aminotetrazole or the like, or a 1,2,3-azole. The liquid etchant permits a copper surface to be roughened in an acicular manner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.