Atomic layer deposition of hafnium dioxide (HfO2) on silicon substrates was studied. It was revealed that due to low adsorption probability of HfCl4 on silicon substrates at higher temperatures (450-600 degreesC) the growth was non-uniform and markedly hindered in the initial stage of the HfCl4-H2O process. In the HfI4-H2O and HfI4-O-2 processes, uniform growth with acceptable rate was obtained from the beginning of deposition. As a result, the HfI4-H2O and HfI4-O-2 processes allowed deposition of smoother, more homogeneous and denser films than the HfCl4-H2O process did. The crystal structure developed, however, faster at the beginning of the HfCl4-H2O process. (C) 2004 Elsevier B.V. All rights reserved.