Comparative determination of the electron temperature in Ar- and N-2-plasmas with electrostatic probes, optical emission spectroscopy OES and energy dispersive mass spectrometry EDMS

The electron temperature T-e as the often most essential parameter for appl ications of low pressures plasma has been derived from comparative in situ measurements with a single and a double electrostatic probe, and with optic al emission spectroscopy OES and energy dispersive mass spectrometry EDMS a s remote techniques. Electrodeless rf discharges maintained by electron cyc lotron wave resonance ECWR in pure Ar and N-2 in the pressure regime from 1 0(-2) to 1 Pa have been used as sample plasmas. The evaluation of the OES- and EDMS-signals is described in detail. The pressure dependence of the T-e -results derived therefrom is found to compare well with the data from the probe measurements, and with calculations from a charge carrier balance equ ation. By matching the OES data to the absolute T-e-values from the probe m easurements, numerical expressions have been obtained by which Te can be qu antitatively calculated from the intensity ratios between selected emission lines from the Ar- and the N-2-plasma. Furthermore, the EDMS-results are a lso shown to deliver quantitative information about T-e.