Vacuum plasma processor including control in response to DC bias voltage

摘要

A plasma processor chamber includes a bottom electrode and a top electrode assembly having a center electrode surrounded by a grounded electrode. RF excited plasma between the electrodes induces a DC bias on them. A measure of the bottom electrode DC bias controls the capacitance of a first series resonant circuit connected between the center electrode and ground. A measure of the center electrode DC bias controls the capacitance of a second series resonant circuit connected between the bottom electrode and ground.