MONTE-CARLO SIMULATION OF IONS IN A MAGNETRON PLASMA

A simulation of ion dynamics in a planar magnetron discharge is performed using separate three-dimensional Monte Carlo codes for the electrons and ions. First, to predict the ionization sites, the orbits of energetic electrons are simulated for prescribed dc electric and magnetic fields, subject to collision with neutrals at random intervals. In the second code the predicted sites are used as the starting positions of ion trajectories. The ion trajectories are followed taking into account collisions with neutrals, turbulent electric fields, and the dc fields. We report results for ion impact on the cathode and substrate anode surfaces (energy, angle, and spatial distribution) and ion parameters in the plasma (density, drift velocity, random energy, and transit time). To test these results we compare them to several previously reported experiments, and in most cases find good agreement. These simulation methods not only are useful for gaining an understanding of magnetron plasma operation, but may also aid in designing magnetrons.