Plasma processing system including segmented upper electrode connected to variable impedances

Abstract

A plasma processing system for processing substrates includes a variable impedance circuit for providing S impedances at a first RF frequency for each of S segments of a first electrode, respectively, where S is an integer greater than one. For each of the S segments, the variable impedance circuit includes a switched resistor circuit including a first plurality of resistors and a first plurality of switches configured to vary an impedance of the switched resistor circuit in a first impedance range at the first RF frequency and a switched capacitor circuit including a second plurality of resistors, a plurality of capacitors and a second plurality of switches configured to vary an impedance of the switched capacitor circuit in a second impedance range at the first RF frequency. A switch configuration controller is configured to select one of the switched resistor circuit and the switched capacitor circuit.

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