Correlation between excitation and electron temperature in 50 Hz pulsed Ar–O2 mixture plasma

Abstract

Optical emission spectroscopy is employed to investigate the excitation temperature Texc and electron temperature Te in 50Hz, pulsed DC Ar–O2 mixture plasma. The excitation and electron temperatures are measured as function of current density, pressure and Ar concentration in the mixture. Boltzmann plot method is employed to estimate the excitation temperature Texc whereas electron temperature Te is calculated by using modified Boltzmann plot technique. The results show that both Te and Texc have similar trend i.e., both decreasing with increase in pressure while increasing trend is observed with increase in argon concentration in the mixture. On the other hand small variation is noted regarding change in current density. The results of correlation between electron and excitation temperature suggests that Te can be measured indirectly from Texc if the variation in ratio Te/Texc, as function of discharge parameters, has similar trend.