Patent ID: 8337661

Claim:
A plasma reactor for processing a workpiece, comprising: plural impedance matches and plural RF plasma power generators coupled to deliver respective RF plasma powers from respective ones of said plural RF plasma power generators into said chamber through respective ones of said impedance matches; a controller for providing a time-varying modulation control signal corresponding to a desired process transient cycle and a transient modulator coupled to modulate the output of a first one of said generators in response to said time-varying modulation control signal; and a stabilization RF power generator separate from said plural RF plasma power generators and coupled to deliver RF stabilization power into said chamber, and a follower modulator coupled to modulate the output of said stabilization RF power generator in response to said time-varying modulation control signal; wherein: said first generator comprises a sensor output providing a signal representing a measured level of RF power reflected back to the generator, said signal being coupled to said controller; said controller being programmed to alter the degree of modulation of said stabilization RF power generator to minimize said measured level of RF power reflected back to said generator.