Patent ID: 7705275

Claim:
A substrate support comprising: (a) a top plate of metal comprising (1) a top feedthroughs; (2) a top surface comprising: (i) a plurality of outwardly projecting mesas dispersed across a recessed pocket; (ii) a network of recessed grooves; (iii) a vacuum port terminating in the recessed grooves and connected to a top feedthrough; and (iv) a plurality of gas ports connected to another top feedthrough; and (3) a bottom surface comprising: (i) a groove; (ii) a resistance heater in the groove, the resistance heater comprising a first resistive heating element about a peripheral region of the metal plate and a second resistive heating element about a central region of the metal plate, each resistive heating element being in a tube surrounded by an electrical insulator powder; and (iii) a thermally conductive filler that surrounds the resistance heater and fills in the gap between the resistance heater and the groove; (b) a middle plate of metal comprising a plurality of middle feedthroughs which are aligned to the top feedthroughs of the top plate, the middle plate joined to the top plate by a first brazed bond layer comprising a metal alloy; and (c) a bottom plate of metal comprising a plurality of bottom feedthroughs which are aligned to the middle feedthroughs of the middle plate, the bottom plate joined to the middle plate by a second brazed bond layer comprising a metal alloy, and wherein the top, middle and bottom feedthroughs are sealed around their edges.