Novolak resin precursor, novolak resin and positive photoresist composition containing the novolak resin
US6207788A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 1998 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Jul 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/0236
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A novolak resin precursor is composed of bonded phenolic moieties, one of the hydrogen atoms in the o- or p-positions relative to the hydroxy group of each phenolic moiety is substituted with an alkyl or alkenyl group having 1 to 3 carbon atoms, and the other two hydrogen atoms are bonded through methylene bonds. The content of ortho--ortho bonding is 30 to 70% relative to the number of total methylene bonds and the weight average molecular weight of the precursor is 300 to 10,000. A novolak resin is obtained from this precursor, and a positive photoresist composition comprises this novolak resin. The invention provides a positive photoresist composition that comprises less binuclear compounds, suppresses scum formation, is excellent in terms of definition and coating performance and provides a resist pattern having satisfactory heat resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.