An electrostatic chuck configured for high temperature reduced-pressure processing is described. The electrostatic chuck comprises a chuck body having an electrostatic clamp electrode and an optional heating element, and a heat sink body having a heat transfer surface spaced in close relationship with an inner surface of the chuck body, wherein the heat sink body is configured to remove heat from the chuck body due to the close proximity of the inner surface and the heat transfer surface. The electrostatic chuck further comprises a table assembly configured to support the chuck body and the heat sink body, and an expansion joint disposed between the chuck body and the table assembly, and configured to sealably join the chuck body to the table assembly while accommodating for differential thermal expansion of the chuck body and the table assembly.