Control of Electron Density and Rotation Profiles by Voltage Biased Electrodes in RF Produced Plasma

Using voltage biasing to ten concentric rings, profiles of plasma density and high azimuthal rotation velocity in a supersonic regime were controlled under three magnetic field configurations in a cylindrical magnetized RF produced plasma. Low frequency (< 4 kHz) density oscillation was identified as a drift wave type: propagation in the electron diamagnetic direction, which is opposite to the edge plasma rotation.