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

A method for controlling temperature of a substrate support in a substrate processing system, the method comprising:

• receiving a first current and a second current corresponding to a first heater element and a second heater element, respectively, of a substrate support;
• receiving a first voltage and a second voltage corresponding to the first heater element and the second heater element, respectively;
• calculating a first resistance of the first heater element based on the first voltage and the first current;
• calculating a second resistance of the second heater element based on the second voltage and the second current;
• calculating a first temperature of a first zone of the substrate support based on the first resistance and stored data correlating resistances to temperatures;
• calculating a second temperature of a second zone of the substrate support based on the second resistance and the stored data;
• selectively adjusting the stored data based on a comparison between a sensed temperature and at least one of the calculated first temperature and second temperature;
• and
• separately controlling 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 (i) the first resistance and the first temperature and (ii) the second resistance and the second temperature.