THERMAL REGULATOR, SUBSTRATE PROCESSING APPARATUS, AND METHOD OF CONTROLLING TEMPERATURE OF STAGE

A thermal regulator for controlling temperature of a substantially circular stage comprising a plurality of first segments and a plurality of second segments in a radial direction and in a circumferential direction, each of the first segments and at least two adjacent second segments defining a set of segments, the thermal regulator includes heaters disposed in the first and second segments, respectively, thermal sensors disposed in the first segments, respectively, a controller configured to control the heaters in response to temperatures determined by the thermal sensors, and a segment switch to switch the second segments to be controlled in conjunction with the first segment in each set of segments.