Patent ID: 9236228
Filing Date: 2016-01-12
CPC Classification: H01J

Claim Text:
1. A method for processing a substrate in a plasma processing system having a processing chamber coupled to a plurality of RF power supplies for sustaining a plasma within said processing chamber, comprising: operating a first RF power supply to deliver a first RF signal between a high power state and a low power state to the processing chamber, wherein said first RF signal has a first frequency; and operating a second RF power supply of said plurality of RF power supplies in a fixed frequency mode so that the second RF power supply is not permitted to self-tune a frequency of a second RF signal output to the processing chamber by said second RF power supply, wherein said second RF signal operates with a first fixed RF frequency value and a second fixed RF frequency value, wherein the first and second fixed RF frequency values are learned earlier during a learning phase when said first RF signal is respectively at the high power state and said low power state.