Method and apparatus for removing coating from substrate
US4859303A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 1987 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Oct 9, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/004
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a method and apparatus for plasma stripping a polymer photoresist coating from a semiconductor substrate, positively charged species are removed from an activated gas flow before the gas flow is brought into contact with the coating to strip the coating from the substrate. The positively charged species may be removed by bringing the activated gas into contact with a grounded conducting surface to discharge the positively charged species, or by passing the activated gas through a negatively charged electrostatic filter to filter out positively charged species. The removal of positively charged species from the gas flow reduces or eliminates build up of positive charge on an outer surface of the photoresist coating so as to avoid driving mobile positively charged ions from the photoresist into the substrate, thereby avoiding contamination of the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.