We report a hetero-epitaxial growth of cubic single crystalline HfO2 film on Si substrates as high k materials by pulse laser ablation (PLA) at 820 degrees C. To eliminate the interfacial defects, the HfO2 film has then been annealed at 900 degrees C for 5 min in N-2. Reflection high-energy electron diffraction (RHEED) results indicate orientation of the HfO2 film on Si substrates corresponding to (001)(HfO2)parallel to(001)(Si) and [011](HfO2)parallel to[011](Si). An interface layer has been revealed by high-resolution transmission electron microscope (HRTEM). Through capacitance-voltage (C-V) and current-voltage (I-V), it has been obtained that the leakage current of the HfO2 gate insulator with dielectric constant of 26 is 5 x 10(-6) A/cm(2) at 1 V. (C) 2010 Elsevier B.V. All rights reserved.