System, Method and Apparatus for Improving Accuracy of RF Transmission Models for Selected Portions of an RF Transmission Path

Method for determining an RF transmission line model for a complete RF transmission system comprising:

• generating a baseline RF transmission line model characterizing the RF transmission system, the baseline RF transmission line model having a plurality of stages ending at an input to an electrostatic chuck;
• calculating at least one of a plasma RF voltage (Vrf) and/or a plasma RF current (Irf) and/or a plasma RF power (Prf) and/or a corresponding RF induced DC bias voltage from the baseline RF transmission line model;
• adding an end module to the baseline RF transmission line model to create at least one revised RF model, the end module including the electrostatic chuck, a plasma and an RF return path including selecting an initial random value for each of equivalent serial and shunt RLC values representing the end module;
• calculating at least one of a revised plasma RF voltage (V′rf) and/or a revised plasma RF current (I′rf) and/or a revised plasma RF power (P′rf) and/or a corresponding revised RF induced DC bias voltage from each of the at least one revised baseline RF models;
• scoring the revised RF transmission line models to identify a best fitting revised RF transmission line model including:
• selecting at least one bias model to test each revised RF transmission line model;
• testing each revised RF transmission line model with each of the selected at least one bias model;
• storing test results for each of the selected at least one bias model for each of the revised RF model;
• and
• scoring the stored test results according to accuracy of the revised plasma RF voltage (V′rf) and/or a revised plasma RF current (I′rf) and/or a revised plasma RF power (P′rf) and/or a corresponding revised RF induced DC bias voltage corresponding to each of the at least one revised baseline RF models;
• and
• recording the best fitting revised RF transmission line model as a complete RF transmission line model.

A plasma processing system comprising:

• a plasma processing chamber;
• an RF transmission system coupled to an RF input of the plasma processing chamber;
• an RF generator having an output coupled to the RF transmission system;
• and
• a controller coupled to the RF generator and the plasma processing chamber, the controller including logic on computer readable media being executable for adjusting at least one dynamic first principal variable of an RF signal in a plasma in the plasma processing chamber according to a complete RF transmission line model of the RF transmission system to compensate for a difference between the plasma system and a second plasma system, the complete RF transmission line model being determined by:
• generating a baseline RF transmission line model characterizing the RF transmission system, the baseline RF transmission line model having a plurality of stages ending at an input to an electrostatic chuck;
• calculating at least one of a plasma RF voltage (Vrf) and/or a plasma RF current (Irf) and/or a plasma RF power (Prf) and/or a corresponding RF induced DC bias voltage from the baseline RF transmission line model;
• adding an end module to the baseline RF transmission line model to create at least one revised RF transmission line model, the end module including the electrostatic chuck, a plasma and an RF return path;
• calculating at least one of a revised plasma RF voltage (V′rf) and/or a revised plasma RF current (I′rf) and/or a revised plasma RF power (P′rf) and/or corresponding revised RF induced DC bias voltage from each of the at least one revised baseline RF transmission line models;
• scoring the revised RF transmission line models to identify a best fitting revised RF transmission line model;
• and
• recording the best fitting revised RF transmission line model as a complete RF transmission line model.