Technique for monitoring and controlling a plasma process
US7476849B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 2006 |
| Grant date | Jan 13, 2009 |
| Priority date | — |
| Expiry date | Sep 10, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An in-situ ion sensor is disclosed for monitoring ion species in a plasma chamber. The ion sensor may comprise: a drift tube; an extractor electrode and a plurality of electrostatic lenses disposed at a first end of the drift tube, wherein the extractor electrode is biased to attract ions from a plasma in the plasma chamber, and wherein the plurality of electrostatic lenses cause at least one portion of the attracted ions to enter the drift tube and drift towards a second end of the drift tube within a limited divergence angle; an ion detector disposed at the second end of the drift tube, wherein the ion detector detects arrival times associated with the at least one portion of the attracted ions; and a housing for the extractor, the plurality of electrostatic lenses, the drift tube, and the ion detector, wherein the housing accommodates differential pumping between the ion sensor and the plasma chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.