Method of end point detection in a plasma etching process
US5160576A · kind A · utility
12Cited by
8References
22Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1991 |
| Grant date | Nov 3, 1992 |
| Priority date | — |
| Expiry date | Mar 5, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2003/1213
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of optically detecting a change in intensity of an emission peak in a plasma process, such as a plasma etching process, by reflecting an emission spectrum of radiation from the plasma reaction off of a pair of rugate filters. The reflected emission spectrum has increased in-band reflections and decreased out-of-band reflections which provides reduced noise and an easier-to-detect emission peak. The method can be used for end-point detection in a plasma etching process such as etching of SiO.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.