Titanium oxide (TiO2) films were deposited on silicon substrates at the temperature in the range 50-600 degrees C by DC reactive magnetron sputtering. It was found that the anatase and rutile phases co-existed in the TiO2 films deposited at 450-500 degrees C, while only the anatase phase existed in those deposited at other temperatures. The mechanism of such a crystallization behavior of TiO2 films is preliminarily explained. (c) 2007 Elsevier B.V. All rights reserved.