Cyclic D2O radical anneal was interposed in atomic layer deposition (ALD) of HfO2 gate dielectrics on Si. A significant improvement on the thermal stability of the gate dielectrics against postdeposition anneal (PDA) can be achieved from the incorporation of this special anneal technique into the ALD process. A low equivalent oxide thickness of the HfO2 gate dielectrics was retained even after 900 degrees C PDA. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3526310] All rights reserved.