Rf impedance matching with continuous wave and pulsing sources

A method of impedance matching comprising:

• providing, from a CW RF source, a CW RF signal to a load;
• providing, from a pulsing RF source, a pulsing RF signal to the load, the pulsing RF signal comprising (a) a first pulse level having a first pulse level time duration, and (b) a second pulse level having a second pulse level time duration;
• operably coupling a matching network between the CW RF source and the load, the matching network comprising at least one electronically variable reactance element (EVRE);
• operably coupling a control circuit to (a) the matching network and (b) at least one of the pulsing RF source or a sensor positioned between the pulsing RF source and the load;
• receiving one or more signals indicative of values of a parameter of the pulsing RF signal;
• for the first pulse level, causing the matching network to impedance match between the CW RF source and the load by altering the at least one EVRE based on a value of the parameter during the first pulse level time duration;
• and
• for the second pulse level, causing the matching network to impedance match between the CW RF source and the load by altering the at least one EVRE based on a value of the parameter during the second pulse level time duration.

A semiconductor processing tool comprising:

• a plasma chamber configured to deposit a material onto a substrate or etch a material from the substrate;
• and
• a first impedance matching network operably coupled to the plasma chamber and configured to be operably coupled to a CW RF source configured to provide a CW RF signal to the plasma chamber, the first impedance matching network comprising at least one electronically variable reactance element (EVRE);
• and
• a second impedance matching network operably coupled to the plasma chamber and configured to be operably coupled to a pulsing RF source configured to provide a pulsing RF signal to the load, the pulsing RF signal comprising (a) a first pulse level having a first pulse level time duration, and (b) a second pulse level having a second pulse level time duration;
• and
• a control circuit operably coupled to (a) the first impedance matching network and (b) at least one of the pulsing RF source or a sensor positioned between the pulsing RF source and the load, wherein the control circuit is configured to:
• receive one or more signals indicative of values of a parameter of the pulsing RF signal;
• for the first pulse level, cause the matching network to impedance match between the CW RF source and the load by altering the at least one EVRE based on a value of the parameter during the first pulse level time duration;
• and
• for the second pulse level, cause the matching network to impedance match between the CW RF source and the load by altering the at least one EVRE based on a value of the parameter during the second pulse level time duration.