Endpoint control for small open area by RF source parameter Vdc
US6930049B2 · kind B2 · utility
1Cited by
2References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2001 |
| Grant date | Aug 16, 2005 |
| Priority date | — |
| Expiry date | Dec 2, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76802
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of detecting endpoint of a plasma etching system that measures the DC voltage drop across both the sheath and the film being etched. When the film is nearly removed, a drop in voltage indicates thinning of the film which detects endpoint for etching before optical emission techniques. The voltage drop is measured across resistors within the matching network.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.