The HfO2 high-k thin films have been deposited on p-type (1 0 0) silicon wafer using RF magnetron sputtering technique. The XRD, AFM and Ellipsometric characterizations have been performed for crystal structure, surface morphology and thickness measurements respectively. The monoclinic structured, smooth surface HfO2 thin films with 9.45 nm thickness have been used for Al/HfO2/p-Si metal-oxide-semiconductor (MOS) structures fabrication. The fabricated Al/HfO2/Si structure have been used for extracting electrical properties viz dielectric constant, EOT, barrier height, doping concentration and interface trap density through capacitance voltage and current-voltage measurements. The dielectric constant, EOT, barrier height, effective charge carriers, interface trap density and leakage current density are determined are 22.47, 1.64 nm, 1.28 eV, 0.93 x 10(10), 9.25 x 10(11) cm(-2) eV(-1) and 9.12 x 10(-6) A/cm(2) respectively for annealed HfO2 thin films. (C) 2011 Elsevier Ltd. All rights reserved.