Method of stripping a resist mask
US5773201A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 1994 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Feb 9, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/427
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for removing a used organic resist in a downstream ashing apparatus on a silicon semiconductor wafer in which water vapor is added to an oxygen plasma gas generated by microwaves. The addition of the water vapor lowers an activation energy of the ashing reaction and increases the reactive species generated in the plasma. Accordingly, the ashing rate is increased even at a wafer processing temperature as low as 150.degree. C. The addition of water vapor increases the ashing rate for a wide range of the percentage of water content, such as 5 to 80%, allowing easy control of the process. The lowered operating temperature prevents contamination of the semiconductor wafer. Since CF.sub.4 is not used the SiO.sub.2 layer is protected from being undesirably etched and the semiconductor characteristics do not deteriorate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.