Endpoint detection for high density plasma (HDP) processes
US6919279B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 2002 |
| Grant date | Jul 19, 2005 |
| Priority date | — |
| Expiry date | Mar 7, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32963
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and system are provided for endpoint detection of plasma chamber cleaning or plasma etch processes. Optical emission spectroscopy is utilized to determine a spectral emission ratio of two or more light emitting reaction components at wavelengths in close proximity. When a spectral emission ratio or derivative thereof or mathematical function thereof falls below a selected threshold value, the plasma process may be terminated within a calculated time from the threshold value prior to an endpoint value cutoff. Advantageously, the system and methods of the present invention provide real-time, in-situ monitoring of plasma clean or etch processes to optimize the process and avoid under-cleaning or over-cleaning.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.