Modified floating harmonic method by analyzing harmonic currents of a DC blocking capacitor

Abstract

The floating harmonic method (FHM) is a diagnostic method to obtain plasma parameters by analyzing harmonic currents of driving frequency to a probe. In the FHM, the harmonic currents are measured through a sensing resistor and a DC floating potential is maintained by a DC blocking capacitor. In this thesis, the current sensing resistor is eliminated by modifying FHM’s measurement circuit, and the DC blocking capacitor is used for measuring the harmonic currents. Since there is no voltage drop across the sensing resistor, compensation of sheath voltage is not necessary. In this method, plasma densities and electron temperatures are measured in argon Inductively coupled plasma and the results are compared with those obtained from electron energy probability functions.