Investigation of glow discharge plasma energy distribution using a gridded energy analyzer considering plasma-facing materials related processes

Abstract

Considering the effects of glow discharge plasmas on plasma-facing materials and the applications such as coating, cleaning and surface treating, this work has been done to investigate the energy of ions of dc glow discharge plasmas. On the way towards this goal, a plasma chamber has been simulated via COMSOL Multiphysics software. Then, a gridded energy analyzer has been simulated and designed. In the next step, the analyzer has been constructed and tested to measure the energy of plasma ions. The devise contains a grid which is negatively biased to the same potential as the glow discharge cathode electrode. It discriminates plasma ions based on their energies, which are accelerated due to sheath potential drop before colliding with the cathode. The obtained energy distribution function from experiments has been compared to that of simulated plasma. The experimental results show that there are different groups of ions each in local thermal equilibrium in dc glow discharge plasmas.