This study presents an examination of the interfacial and electrical properties of HfO2 films grown by plasma-enhanced atomic layer deposition with tetrakis(diethylmethylamino) hafnium and O-2 precursors on GaAs substrates cleaned with HF and then (NH4)(2)S cleaning for three different dipping times. Systematic X-ray photoelectron spectroscopy analyses both before and after the HfO2 deposition revealed that the optimal cleaning time in terms of the removal of the As-and Ga-oxides was significantly reduced by the partial "self-cleaning" process that occurred at a substantially lower deposition temperature of only 200 degrees C, possibly due to the plasma effect. The frequency dispersion characteristics were strongly dependent on the cleaning method, however, the hysteresis characteristics were not. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3569751] All rights reserved.