Wet etching of thermally or chemically cured polyimide
US4846929A · kind A · utility
17Cited by
7References
37Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 13, 1988 |
| Grant date | Jul 11, 1989 |
| Priority date | — |
| Expiry date | Jul 13, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0793
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Polyimide is etched by contacting the polyimide with an aqueous solution of a metal hydroxide followed by contact with an acid followed by contact with an aqueous solution of a metal hydroxide. Etching of chemically cured polyimide can be enhanced by employing a presoaking in hot water. Also, partially etched chemically cured polyimide is removed with a concentrated acid solution. In preparing a metal coated polyimide structure for subsequent gold plating, two flash etching steps with the polyimide etch between are employed after developing the photoresist.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.