US Patent 7705275 Substrate support having brazed plates and resistance heater

A substrate support comprises top, middle and bottom plates which are brazed together. The top plate has a top surface with a plurality of outwardly projecting mesas dispersed across a recessed pocket, a network of recessed grooves, a vacuum port terminating in the recessed grooves, and plurality of gas ports. The middle plate has a plurality of middle feedthroughs aligned to corresponding top feedthroughs of the top plate, and the bottom plate has a plurality of bottom feedthroughs aligned to the middle feedthroughs of the middle plate. The top and middle plates are joined by a first brazed bond layer and the middle and bottom plates are joined by a second brazed bond layer.