Neutral and charged particle simulation of a RF argon plasma

Abstract

Particle-in-cell Monte Carlo simulations of one-dimensional capacitively coupled radio frequency glow discharges were performed for low-pressure argon plasmas. The present scheme includes the motions and collisions both of neutral species and of charged particles. To optimize computational efforts, a time-averaging technique was considered for the electric field while larger time steps (compared to those used for charged particles) were used for neutral species motion and collisions. The results show that the neutral Ar density is almost uniform between the unheated electrodes, consistent with the assumptions of earlier `charged particle' simulations. The model was applied to `heated wall' cases in which one of the electrodes (the cathode) is heated for different chamber pressures. The wall heating changes the neutral species temperature and density profiles, which affect the plasma density profile and the energy of ions impinging on the cathode. Lowering the pressure changed the plasma density and energy distributions of electrons and impinging ions.