The effect of deposition temperature on the growth rate, band gap energy and electrical properties of HfO2 thin film deposited by atomic layer deposition (ALD) has been investigated. By means of characterization of spectroscopy ellipsometry and ultraviolet visible spectroscopy, the growth rate and optical constant of ALD-derived HfO2 gate dielectrics are determined precisely. The deposition temperature dependent electrical properties of HfO2 films were determined by capacitance voltage (C-V) and leakage current density voltage (1 V) measurements. The leakage current mechanism for different deposition temperature has been discussed systematically. As a result, the optimized deposition temperature has been obtained to achieve HfO2 thin film with high quality. (C) 2015 Elsevier Ltd. All rights reserved.