Acidic ion exchange resin as a catalyst to synthesize a novolak resin and photoresist composition therefrom
US5665517A · kind A · utility
8Cited by
31References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 11, 1996 |
| Grant date | Sep 9, 1997 |
| Priority date | — |
| Expiry date | Jan 11, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/0236
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention provides methods for producing water insoluble, aqueous alkali soluble novolak resins having consistent molecular weight and a very low level of metal ions, utilizing a solid acid condensation catalyst. A method is also provided for producing photoresist composition having a very low level of metal ions from such novolak resins and for producing semiconductor devices using such photoresist compositions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.