Analysis of radiofrequency discharges in plasma
US5135604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1990 |
| Grant date | Aug 4, 1992 |
| Priority date | — |
| Expiry date | Dec 4, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/628
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Separation of laser optogalvanic signals in plasma into two components: (1) an ionization rate change component, and (2) a photoacoustic mediated component. This separation of components may be performed even when the two components overlap in time, by measuring time-resolved laser optogalvanic signals in an rf discharge plasma as the rf frequency is varied near the electrical resonance peak of the plasma and associated driving/detecting circuits. A novel spectrometer may be constructed to make these measurements. Such a spectrometer would be useful in better understanding and controlling such processes as plasma etching and plasma deposition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.