Ion Energy Distribution Functions in Capacitively Coupled Argon-Xenon Plasmas
Maximilian Klich, Sebastian Wilczek, Jan Trieschmann, Thomas Mussenbrock, Ralf Peter Brinkmann
DPG Frühjahrstagung 2018, Erlangen
While accurate control of the ion energy is a crucial requirement of industrial plasma processes, its intrinsics are still not fully understood. Specifically, plasmas used for etching or thin film deposition consist of various gas and ion species. Thus, the control of the ion dynamics of multiple gas and ion species is a topic of current research. In order to contribute to this topic, we investigate low-pressure argon-xenon discharges via Particle-In-Cell/Monte Carlo Collision (PIC/MCC) simulations. The main advantage of this noble gas mixture is the simple chemistry, which leads to a feasible number of ion species and collision processes to be considered. The ion energy distribution functions (IEDFs) at the electrodes of a geometrically symmetric capacitively coupled radio-frequency discharge provide information about the ion dynamics within the discharge volume. Several variations of the discharge parameters (e.g., pressure, driving voltage and gas composition) are presented in order to influence the ion dynamics. Furthermore, a power balance model is used, which allows for a better understanding of the obtained results. The final goal of this study is to achieve deeper insights about complex (e.g., bimodal) IEDFs of different ion species.