Simulation of electron energy gain in inductively coupled plasmas driven at 13.56, 27.12, and 40.68 MHz under confronting divergent magnetic fields

Abstract Electron heating process in inductively coupled plasmas driven under confronting divergent magnetic fields is investigated by Monte Carlo simulations. Enhancement of the electron energy gain due to the partial resonance is demonstrated by adopting driving frequencies 27.12 and 40.68 MHz higher than the conventional 13.56 MHz. The present model reactor is arranged so that the regions of strong magnetic fields near a magnetic coil and high electric fields near the RF antenna overlap. In this configuration, with increasing driving frequency, the resonant region where the electron heating by the partial resonance occurs shifts to the region of strong magnetic and high electric fields. The enhanced electron heating observed at the higher driving frequencies indicates that the partial resonance occurs in a wider region including more electrons and under higher electric fields. The power deposition by the partial resonance exceeds the electron cooling effect of the strong magnetic fields.