An electrostatic chuck is described with external flow adjustments for improved temperature distribution. In one example, a method for adjusting coolant flow in an electrostatic chuck includes heating a dielectric puck, the dielectric puck being for electrostatically gripping a silicon wafer. Heat is detected at a plurality of locations on a top surface of the dielectric puck, the locations each being thermally coupled to at least one of a plurality of coolant chambers of the electrostatic chuck. A plurality of valves are adjusted to control coolant flow into the coolant chambers based on the detected heat.