The growth of TiO2 films in the anatase crystal structure was investigated using reactive sputter deposition with H2O serving as the oxidizing species. With water vapor, the formation of phase-pure anatase TiO2 thin films via epitaxial stabilization on (001) LaAlO3 was achieved, although crystallinity was slightly inferior to that obtained when O-2 was employed. Films grown using water vapor exhibited a rougher surface morphology indicating a difference in growth mechanisms. At low H2O pressure, the formation of a TinO2n-1 Magneli phase was observed. When hydrogen was employed during growth, mixed phase films of rutile and anatase resulted. The development of crystallinity and phase as a function of deposition temperature and oxidant pressure are discussed. (C) 2003 Elsevier B.V. All rights reserved.