Scanning impedance measurement in a radio frequency plasma processing chamber

Abstract

Embodiments of the disclosure include a method of processing a substrate in a plasma processing system, comprising delivering an RF signal, by an RF generator, through an RF match to an electrode assembly disposed within the plasma processing system, wherein while delivering the RF signal the RF match is set to a first matching point, and delivering a voltage waveform, by a waveform generator, to the electrode assembly disposed within the plasma processing system while the RF signal is delivered to the electrode assembly. The method includes receiving, by the RF match, a synchronization signal from a RF generator or the waveform generator, measuring, by an output sensor of the RF match, a first set of impedance related data of the plasma processing system over a first time period, the first time period beginning after a first delay triggered by a first portion of a first waveform pulse of the synchronization signal, measuring, by the output sensor of the RF match, a second set of impedance related data of the plasma processing system over a second time period, the second time period beginning after a second delay triggered by the first portion of the first waveform pulse of the synchronization signal, calculating, by the RF match, a combined impedance parameter based on the measured first set of impedance related data and the measured second set of impedance related data, and adjusting a matching parameter within the RF match based on the calculated combined impedance parameter to achieve a second matching point.