Electrostatic chuck for use in semiconductor processing

A semiconductor substrate processing apparatus includes a vacuum chamber having a processing zone in which a semiconductor substrate may be processed, a process gas source in fluid communication with the vacuum chamber for supplying a process gas into the vacuum chamber, a showerhead module through which process gas from the process gas source is supplied to the processing zone of the vacuum chamber, and a substrate pedestal module. The substrate pedestal module includes a platen made of ceramic material having an upper surface configured to support a semiconductor substrate thereon during processing, a stem made of ceramic material, and coplanar electrodes embedded in the platen, the electrodes including an outer RF electrode and inner electrostatic clamping electrodes, the outer RF electrode including a ring-shaped electrode and a radially extending lead extending from the ring-shaped electrode to a central portion of the platen, wherein the ceramic material of the platen and the electrodes comprise a unita