Power absorption in electrically asymmetric dual frequency capacitive radio frequency discharges

TLDR: In this paper, the authors investigated the power absorbed by the electrons Pe as a function of θ and time experimentally, by a particle in cell simulation, and an analytical model.

Abstract: The symmetry of capacitive radio frequency discharges can be controlled via the electrical asymmetry effect by driving one electrode with a fundamental frequency and its second harmonic. In such electrically asymmetric discharges, the mean ion energies at both electrodes are controlled separately from the ion flux by tuning the phase angle θ between the harmonics at fixed voltage amplitudes. Here, the question why the ion flux is nearly independent of θ is answered by investigating the power absorbed by the electrons Pe as a function of θ and time experimentally, by a particle in cell simulation, and an analytical model. The dynamics of Pe is understood by the model and is found to be strongly affected by the choice of θ. However, on time average, Pe is nearly constant, independently of θ. Thus, the ion flux remains approximately constant. In addition, it is shown that the absolute value of the individual voltages across the powered and grounded electrode sheath vary linearly with the dc self-bias. Howeve...