Lam Research Corporation
Use of voltage and current measurements to control dual zone ceramic pedestals

Abstract:

A controller for a substrate processing system includes a resistance calculation module configured to receive a first current and a second current corresponding to a first heater element and a second heater element, respectively, of a substrate support, receive a first voltage and a second voltage corresponding to the first heater element and the second heater element, respectively, calculate a first resistance of the first heater element based on the first voltage and the first current, and calculate a second resistance of the second heater element based on the second voltage and the second current. A temperature control module is configured to separately control power provided to the first heater element and the second heater element based on the first resistance and the second resistance, respectively, and respective relationships between the first and second resistances and first and second temperatures of the substrate support.