PIC-MCC modeling of dusty plasma

Abstract

Dust particles may occur in RF (radio-frequency) discharges for a host of reasons; these include gas-phase nucleation and coagulation within the plasma itself and trapping of dust particles from sputtering and etching of wall material and other external sources. The dust particles are most often negatively charged due to electron capture from the plasma. When the amount of dust accumulation is sufficiently large, it modifies the plasma evolution and the discharge characteristics. In this work, we develop a PIC-MCC based two dimensional model to study the behaviour of a dusty radio frequency discharge in Argon. The simulation model effectively includes not only the ion and electron interaction with each other and the neutral gas molecules but also charged-particle interactions with the dust. The dust particles are assumed to be immobile, however their charge content and mass may grow due to capture of electrons or positive ions. Scattering interactions are also modeled. The evolution of the discharge parameters are traced under the dynamically changing dust content. The effect of various parameters like gas pressure and initial dust loading are studied. The evolution of the charge on the dust plasma and the corresponding change in discharge parameter is traced.