a chamber;

a substrate support disposed in the chamber, the substrate support having an outer periphery surrounding a horizontal upper surface, the outer periphery defined by a vertical outer sidewall; and

a temperature controller including a thermal section disposed under the substrate support and a coupling section including at least one coupling section member protruding upward from an outermost edge portion of the thermal section,

wherein the thermal section includes a first plate and a second plate spaced apart in a horizontal direction under the substrate support,

wherein the first and second plates each include a planar upper surface that lies in a same horizontal plane that is parallel with the horizontal upper surface of the substrate support, and outer peripheries of the planar upper surface of each of first and second plates extend past and are curved along respective vertical outer sidewall portions of the substrate support, and

wherein each of the first plate and the second plate is coupled to an outer side portion of the substrate support by a coupling section member from among the at least one coupling section member, and each coupling section member extends vertically upward from the planar upper surface of a respective one of the first and second plates along the vertical outer sidewall of the substrate support and is attached to the vertical outer sidewall of the substrate support.