THE ROLE OF HEAVY-PARTICLES IN KINETICS OF LOW CURRENT DISCHARGES IN ARGON AT HIGH-ELECTRIC-FIELD TO GAS NUMBER DENSITY RATIO

We have developed a coupled system of Monte Carlo simulation codes for modeling of electron, ion, and fast neutral kinetics in low pressure, low current discharges. The procedure was tested for ion drift tube d ata by using different cross-section sets including the recent anisotr opic set of Phelps [A. V. Phelps, J. Appl. Phys. 76, 747 (1994)]. The code was applied to modeling absolute emission profiles obtained at ve ry high electric field to gas number density ratio, where heavy partic le excitation dominates electron excitation by more than two orders of magnitude, and also to an inhomogeneous field experiment of Scott and Phelps [D. A. Scott and A. V. Phelps, Phys. Rev. A 43, 3043 (1991)]. The qualitative agreement between the Monte Carlo and experimental res ults is good, giving confidence in the available models and data for i on and fast neutral transport in gas discharges, and for their interac tion with surfaces. (C) 1998 American Vacuum Society.