Abstract
AbstractThe negative oxygen ion density is studied experimentally in the high‐density helicon device VINETA by laserinduced photodetachment. The measurements indicate a negative ion density being higher than the electron density in contrast to previous experiments in helicon oxygen discharges. The dependency of the relative negative ion density on the oxygen gas pressure and rf‐power is in good qualitative agreement with observations in low temperature RF inductive and capacitive discharges, but differ quantitatively by one order of magnitude. To understand the basic physics in the helicon discharges, the measurements are compared to a zero dimensional reaction rate model of the electronegative oxygen discharge. The particle densities are calculated via rate equations estimated fromcollisional cross sections assumingMaxwellian electron energy distribution functions. The model shows that the electron temperature is the most sensitive parameter governing the formation of negative oxygen ions. Additionally, the differences to previous experimental measurements in rf discharges can be explained by different electron temperature and plasma losses to the walls (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.