Method and apparatus for end point detection
US5045149A · kind A · utility
36Cited by
16References
10Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 22, 1990 |
| Grant date | Sep 3, 1991 |
| Priority date | — |
| Expiry date | Jun 22, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/62
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and an apparatus for detecting the endpoint in a plasma etching process is disclosed. The invention uses a positive filter and a negative filter simultaneously to generate a first and a second signal respectively. The first and second signals are combined to form a combined signal. A change in the combined signal is indicative of the endpoint.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.