Chamber impedance management in a processing chamber

Abstract

Embodiments of the disclosure include an apparatus and a method for controlling plasma uniformity by controlling plasma density in the bulk plasma over the center region and circumferential edge region of the substrate. Plasma uniformity can be controlled by use of an RF tuning circuit coupled to one of a plurality of electrodes positioned relative to a substrate during plasma processing. By adjusting the electrical characteristics of at least one of the RF tuning circuits, the effect that the generated RF fundamental frequency and related RF harmonic frequencies have on the plasma processing results can be controlled. Beneficially, the use of one or more of the tuning circuits and methods of using the same may be used to provide individual tuning knobs for controlling reactive neutral species concentration, ion energy and angular distribution, ion directionality and directionality uniformity, and separately controlling ion flux and reactive neutral species uniformity across the surface of the substrate.