Method and apparatus for improved plasma processing uniformity

Abstract

A method and apparatus for generating and controlling a plasma () formed in a capacitively coupled plasma system () having a plasma electrode () and a bias electrode in the form of a workpiece support member (), wherein the plasma electrode is unitary and has multiple regions (R) defined by a plurality of RF power feed lines () and the RF power delivered thereto. The electrode regions may also be defined as electrode segments () separated by insulators (). A set of process parameters A={n, τ, Φ, P, S; L} is defined; wherein n is the number of RF feed lines connected to the electrode upper surface at locations L, τis the on-time of the RF power for the iRF feed line, Φis the phase of the iRF feed line relative to a select one of the other RF feed lines, Pis the RF power delivered to the electrode through the iRF feed line at location L, and S is the sequencing of RF power to the electrode through the RF feed lines. One or more of these parameters are adjusted so that operation of the plasma system results in a workpiece () being processed with a desired amount or degree of process uniformity.