A substrate processing system includes a first chamber including a substrate support. A showerhead is arranged above the first chamber and is configured to filter ions and deliver radicals from a plasma source to the first chamber. The showerhead includes a heat transfer fluid plenum, a secondary gas plenum including an inlet to receive secondary gas and a plurality of secondary gas injectors to inject the secondary gas into the first chamber, and a plurality of through holes passing through the showerhead. The through holes are not in fluid communication with the heat transfer fluid plenum or the secondary gas plenum.