Study on RF magnetron discharges of oxygen/argon mixture by the particle-in-cell/Monte Carlo method

Summary form only given, as follows. The characteristics of rf planar magnetron discharges of O/sub 2//Ar mixture are clarified using the Particle-in-Cell/Monte Carlo (PIC/MC) method. The simulation is carried out for axisymmetrical magnetic fields. The spatial and temporal behavior of magnetron discharge is examined in detail. The total pressure and temperature of mixture gas are 5mTorr and 323K, respectively The voltage amplitude is 200V. The magnetization in the magnets is 0.25T. We change mole fraction X/sub O2/ of oxygen. The O/sup -/ ions are trapped in the plasma bulk by the time-averaged potential The spatial distribution of the density of O/sup -/ ions is governed by a balance of generation and loss of O/sup -/. The positive ions Ar, O/sub 2//sup +/, and O/sup +/ are distributed in such a way that the charge neutrality is kept in the plasma bulk. Consequently, the spatial distributions of Ar/sup +/, O/sub 2//sup +/, and O/sup +/ have two peaks. The number densities of Ar/sup +/ and O/sup -/ ions drastically increase when oxygen is added to the discharge gas Ar. In the case when mole fraction X/sub O2/ of oxygen increases, the self-bias voltage on the target decreases. This phenomenon is investigated in detail and a, clear physical explanation is presented.