Computational study of plasma composition influence on sheath formation

Low-temperature plasmas, especially plasma of electronegative gases, are widely used in present plasma-assisted material processing. The introduction of electronegative gas into inert gas plasma brings not only new types of charged particles but also new interactions with the particles of neutral background. These mechanisms affect the transport of charged species from the plasma to immersed substrates and influence the corresponding surface processes. The present work is devoted to computer simulation analysis of the interaction of a Langmuir probe with oxygen/argon plasma. In this calculation, the main difficulty originates from the lack of exact experimental data for the separate influence of negative oxygen ions and that of oxygen neutrals on the sheath formation around the probe or substrate. (C) 2009 Elsevier Ltd. All rights reserved.