Dusty sheaths in plasmas

Abstract

Self-consistent dusty sheaths are simulated by the PIC/MC method in both plasmas with bi-thermal electrons and low-pressure RF discharges with a secondary electron emission from electrodes. The simulations are carried out by using plasma evolution without special boundary conditions for the sheaths that allows getting a self-consistent description of the sheaths. Simulation results show that dust particles can essentially influence spatial distributions of plasma parameters in the sheaths due to the space electric charge of the dust particles and a non-equilibrium of the electron energy distribution function. In particular, the spatial distributions of a self-consistent electric potential can be non-monotonic so that charged dust particles can protect electrodes from an intensive ion sputtering by decreasing the energy of ions arriving to the electrodes.