Multi-zone semiconductor substrate supports

A substrate support assembly comprising:

• a top puck characterized by a first surface and a second surface opposite the first surface, wherein the top puck defines a recessed ledge at an outer edge of the first surface of the top puck;
• a heater disposed on the recessed ledge of the top puck;
• a plurality of thermally insulating standoffs that are positioned between the heater and the top puck and that space the heater apart from the top puck;
• and
• an edge ring seated on the heater and extending about the top puck, wherein the edge ring is maintained free of contact with the top puck.

A substrate support assembly comprising:

• a top puck characterized by a first surface and a second surface opposite the first surface, wherein the top puck defines a recessed ledge at an outer edge of the first surface of the top puck;
• a heater disposed on the recessed ledge of the top puck, wherein the heater comprises:
• a body defining an interior volume in which a heating element extends, and
• a lid coupled with the body, wherein the heating element is in direct contact with the lid about the heater;
• and
• an edge ring seated on the heater and extending about the top puck, wherein the edge ring is maintained free of contact with the top puck.