Pedestal with multi-zone temperature control and multiple purge capabilities

Substrate support assemblies for a semiconductor processing apparatus are described. The assemblies may include a pedestal and a stem coupled with the pedestal. The pedestal may be configured to provide multiple regions having independently controlled temperatures. Each region may include a fluid channel to provide a substantially uniform temperature control within the region, by circulating a temperature controlled fluid that is received from and delivered to internal channels in the stem. The fluid channels may include multiple portions configured in a parallel-reverse flow arrangement. The pedestal may also include fluid purge channels that may be configured to provide thermal isolation between the regions of the pedestal.