Self-consistent particle modelling of dc magnetron discharges ofan O2/Ar mixture

Abstract

The characteristics of planar magnetron discharges of an O2/Ar mixture are clarified using the particle-in-cell/Monte Carlo method.The simulation is carried out for axisymmetrical magnetic fields under the condition of constant total gas pressure of5 mTorr and constant applied voltage of 500 V.The fraction of oxygen partial pressure, p_O2, is changed from 30 % to 70 %.In the case of pO2 = 50% the order of the magnitude of number densities is ne>nAr+>nO2+>nO+>>nO-.As pO2 increases, the electrical field becomes weaker, the cathode sheath becomes thicker, nAr+ decreases, nO2+ and nO+ first increase and then decrease, and the total flux of positive ions onto the cathode decreases.The effect of the arrangement of a magnet system on the total ion flux isalso examined.