Transient voltage analysis on a series capacitor of the floating probe for plasma diagnostics

Abstract

An electrical plasma diagnostic method is proposed to determine plasma density and electron temperature. When two square voltages with different amplitudes are applied to a probe tip, a capacitor connected to the probe is charged due to the current flowing from the plasma. To obtain the plasma parameters, a circuit model with a nonlinear sheath and capacitor is proposed. The electron temperature and plasma density given by the model can be obtained from the ratio of the capacitor voltages. The results are in agreement with those obtained from electron energy probability functions in argon inductively coupled plasma discharge.