Diffusion of cathodic arc plasma in a magnetic filter

Summary form only given, as follows. Summary form only given. A model based on Bohm diffusion is developed to investigate the optimal bias of a magnetic filter used in conjunction with a cathodic arc plasma source. Details regarding the derivation of the model as well as experimental results to corroborate the model are presented. According to the model, the optimal bias at which the magnetic duct produces the maximum plasma output is related to the ion speed, ion mass, ion charge state, arid plasma density in the filter. Even though the magnetic field is taken into account, it is not a variable in the final equation. Our experimental results confirm that the magnetic field has almost no influence on the optimal bias when the magnetic field is above 400 G. The presented work enhances our understanding on the mechanism of plasma transport through the magnetic duct.