Improving etch resistance of a casein-based photoresist
US4230794A · kind A · utility
3Cited by
3References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 16, 1979 |
| Grant date | Oct 28, 1980 |
| Priority date | — |
| Expiry date | Mar 16, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/1157
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The etch resistance of a casein-based photoresist pattern to low specific gravity ferric chloride based etchant solutions is increased by treating the photoresist pattern with a formaldehyde solution containing at least 10 percent formaldehyde by volume by a period of at least 30 seconds, and thereafter drying the photoresist pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.