A TCAD-suited hybrid model for the simulation of the sheath/presheath kinetics of DC or RF driven low-pressure discharges

Summary form only given. In this work, we concentrate on the boundary sheath of a DC or RF driven discharge, and present a model that is both physically accurate and computationally efficient, and that therefore is suited as a tool for technology-oriented computer-aided design or TCAD. The model consists of a self-consistent fluid dynamic part coupled to an efficient Monte-Carlo part. The input given to the model consists of the fluxes of the incoming ions, of the RF current, and of the pressure, composition, and temperature of the background gas. On output, the model provides the values of the electric field and of the particle densities, the total voltage drop across the sheath, and also the energetically and angularly resolved distributions of the positive ions and the energetic neutrals impinging the surface. The model is able to cover realistic process conditions (external bias voltage, non-harmonic modulation of the periodic sheath potential, multiple positive ion species, collisional interaction with the neutral background gas). It describes both the sheath and the presheath in one unified model, and not only, as previous investigations have done, the sheath region alone (Edelberg et al., 1999). This puts the model on a more physical basis, especially for the low-pressure regime, where the dimension of the sheath is much smaller than the mean free path of the particles (Zheng et al., 1995).