RF biasing of liquid metal surface in plasma

Abstract

A system that can deliver a radio frequency (RF) power to a plasma by capacitive coupling (CC) and inductive coupling (IC) was built and tested. The system is equipped with an insulating target reservoir for liquid metals and a planar magnetron electrode. Effects of the applied RF bias on a liquid gallium (Ga) target by using both RF coupling conditions are discussed and presented. Mass spectral and optical emission spectral analyses of the target irradiated with argon and nitrogen plasmas were correlated to the system geometries. It was demonstrated that the IC geometry is more efficient than the CC geometry in terms of plasma density. However, in terms of sputtering a liquid metal target, CC configuration shows a better performance.