We report on the formation of V2O5 semiconductor thin films using rapid thermal annealing (RTA) on sputter-deposited amorphous VOx. DC magnetron sputtering was used to obtain an initial amorphous VOx film on p-Si substrate, followed by O-2- and N-2-RTA at two different temperatures of 400 and 500 degrees C for 3 min. According to X-ray diffraction results, O-2-RTA is more effective to achieve the semiconducting phase, V2O5 than N-2-RTA, which caused some electrically conducting phases such as V4O9 or V6O13 at 400 degrees C. Electrical characterization on Au/vanadium oxide/p-Si structure exhibited ohmic-like behavior when the thin film mainly contains those metallic phases while the structures were strongly rectifying once the film consists of the semiconducting phase, V2O5. (c) 2004 Elsevier B.V. All rights reserved.