The effects of oxygen mixing and rapid thermal annealing (RTA) on the electrical properties of RF sputtered silicon oxide films has been examined. It was found that the insulating property of the sputtered oxide films improved when prepared with oxygen mixing in the sputtering gas and/or after rapid thermal annealing. For films RTA for 50 and 200 s, Schottky emission and space charge Limited conduction were suggested as the transport mechanisms. The infrared results show that the film stoichiometry improved with RTA and/or oxygen mixing.