Monte Carlo Simulation of RF Plasmas and Trial Investigation of Similarity Rule

Detailed properties of RF plasmas sustained by an RF external source of 13.56 MHz and 270 V are presented using self-consistent Monte Carlo simulations in an Ar-like model gas. It is shown that most of the RF external electric field is absorbed in the sheath regions and ions cannot follow the RF field. The time-dependent distribution of the number of excitation collisions is shown to give a physical picture of the moving sheath boundary which oscillates with the RF electric field. It is shown that a lower gas pressure yields a distribution with a wider sheath region which gives dominantly the capacitive component of impedance. A trial investigation of the similarity rule for the bulk region of RF plasmas is presented with respect to the electric field, the electron density, the conduction current density, and the mean electron velocity in the direction of the current.