Fractal modeling of vacuum arc cathode spots

Abstract

This paper introduces a modeling algorithm of spots movement along a working surface of metal cathode during vacuum arc evaporation process with a use of fractal geometry. The proposed spot dynamics model reflects spot self-similar chaotic motion, retrograde rotation due to tangent magnetic field, spontaneous spot splitting and extinction. Several fractal generation techniques are considered: modified Diffusion Limited Aggregation, modified Dielectric Breakdown Method. The advantage of the fractal approach is that unlike computational modeling, it describes the spot movement in a more natural way. Modeling of vacuum arc cathode spots behavior allows reducing production costs of physical vapour deposition coated samples by increasing the cathode utilization efficiency.