‘Virtual IED sensor’ for df rf CCP discharges

Ion-assisted surface processes are the basis of modern plasma processing. Ion energy distribution (IED) control is critical for precise material modification, especially in atomic-level technologies such as atomic layer etching. Since this should be done real time, it requires real-time feedback using fast process sensors. In general case an industrial reactor, when direct IED measurement not possible, can estimated concept a virtual sensor. paper, similar sensor considered asymmetric dual-frequency (df) rf CCP discharge example. It based on calculation method at rf-biased electrode. This approach uses experimentally measured sheath voltage waveform and density (or ion flux) input data, also includes Monte-Carlo simulation motion to take into account effect ion-neutral collisions. To validate approach, experiments were carried out various diagnostics several gases: argon xenon examples with ions nitrogen example molecular ions. shown that all cases possible obtain adequate estimation, close experimental one, reasonably short time (~ tens seconds PC). The results obtained demonstrate possibility