Heated substrate support with thermal baffles

Embodiments of substrate supports for use in a process chamber are provided herein. In some embodiments a substrate support for use in a process chamber includes a pedestal having an upper surface for supporting a substrate and an opposite lower surface, a first heater disposed within the pedestal between the upper surface and the lower surface, and thermal baffles having a plurality of voids that are fluidly isolated from each other disposed between the first heater and the lower surface to reduce heat transfer from the first heater to the lower surface of the pedestal.