High contrast low metal ion positive photoresist developing method using aqueous base solutions with surfactants
US4710449A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1986 |
| Grant date | Dec 1, 1987 |
| Priority date | — |
| Expiry date | Jan 29, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/322
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A novel low metal ion developer composition used in a two step process which provided high contrast images and long developer bath life is provided. The process gives high contrast images. The substrate coated with positive photoresist is exposed then immersed in a "predip" bath, rinsed, and then, immersed in the developer bath, rinsed and dried. This process provided high contrast which does not decrease over the life of the developer system. The system consists of (1) a predip solution containing aqueous non-metal ion organic base and a cationic surfactant adjusted to a concentration that does not give development, and (2) a developer solution containing an aqueous solution of an non-metal ion organic base and a fluorochemical surfactant adjusted to a concentration that provides development. The high contrast is achieved by the cationic surfactant coating the resist and inhibiting the attack on the unexposed resist by the developer while permitting the developer to dissolve away the exposed resist.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.