The direct preparation of p-type transparent conducting Ga-doped SnO2 thin films and their fundamental application in transparent p-n homojunction diode were realized. The films were grown in an active oxygen ambient using reactive rf magnetron sputtering without post-deposition annealing involved. This method improved the electrical properties of the films while maintaining their optical transparency. By growing a p-type thin film on commercial n-type SnO2:F-coated glass, transparent p-n homojunction diode was obtained. It exhibits a distinct current-voltage rectifying characteristic, manifesting this p-type thin film and the fabrication technology are suitable for industrial applications. (C) 2010 Elsevier B.V. All rights reserved.