Electric current oscillations in a parallel‐plate plasma reactor

In a radio‐frequency plasma reactor excited at low frequencies (30–300 kHz), disturbances of the voltage signal and nonlinear oscillations in the current signal were observed. It is shown that the disturbances of the voltage signal can be used to determine the plasma potential and the negative bias. From the nonlinear oscillations of the current signal, the electron density and the electron temperature can be derived by two different methods. One uses the numerical simulation of the voltage and current signals and is described in detail. The other method is based on the analysis of fast current oscillations and is used as a cross check.