Study of SF6 and SF6/O2 plasmas in a hollow cathode reactive ion etching reactor using Langmuir probe and optical emission spectroscopy techniques

Abstract

In this work, electrical and optical studies of SF6 and SF 6/O2 plasmas generated in a hollow cathode reactive ion etching reactor were performed using the Langmuir probe and optical emission spectroscopy techniques, respectively. We carried out an investigation aimed at understanding the influence of radio-frequency power, gas pressure and O 2 gas mixing ratio on plasma parameters, namely electron temperature, electron density and electronegativity, and also atomic fluorine density. The results indicate an increase of up to one order of magnitude in electron density and atomic fluorine in the overall gas volume when compared with a conventional reactive ion etching plasma generated under the same operation conditions. © 2010 IOP Publishing Ltd.