End-point detection in plasma etching by monitoring radio frequency matching network
US5407524A · kind A · utility
47Cited by
4References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1993 |
| Grant date | Apr 18, 1995 |
| Priority date | — |
| Expiry date | Aug 13, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32963
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a system and method for detecting the end-point of a layer being removed from a semiconductor wafer by a plasma etching system. The invention determines end-point by referencing first and second positions of matching components of a matching network between a radio frequency source and the plasma etching system chamber. Comparison of a first position representative of chamber load impedance before end-point, and a second position representative of a change in chamber load impedance is utilized to determine end point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.