Semianalytical Finite Element Method Model for Radio Frequency Sheaths in Single- and Dual-Frequency Capacitively Coupled Plasmas

We propose a semianalytical rf sheath model for single- and dual-frequency capacitively coupled plasmas (CCPs) based on the finite element method (FEM). The one-dimensional nonlinear rf sheath theory and its extension to dual-frequency CCPs are incorporated into the commercial FEM software COMSOL Multiphysics and coupled with the Poisson solver in it. The model enables a time-dependent but rapid simulation of the nonlinear motion of an rf sheath formed around an arbitrary surface geometry of a local region in a single- or dual-frequency CCP. Some application results obtained using the model are demonstrated and validated. (C) 2009 The Japan Society of Applied Physics