Patent ID: 7712434

Claim:
A showerhead electrode assembly, comprising: a showerhead electrode adapted to be mounted in an interior of a vacuum chamber and supply process gas to a gap in which plasma is generated between the showerhead electrode and a substrate support; a gas distribution member comprising an axially extending hub and a laterally extending metal plate attached to the showerhead electrode, the gas distribution member including a first gas passage which supplies process gas to a central plenum between the showerhead electrode and the metal plate and a second gas passage which supplies process gas to an outer plenum between the showerhead electrode and the metal plate; a thermal path member comprising a plate of electrically insulating material surrounding the hub and attached to the gas distribution member; and a heater comprising a plate of thermally conductive material surrounding the hub and attached to the thermal path member; wherein the heater transmits heat to the showerhead electrode through a thermal path comprising the gas distribution member and the thermal path member.