Indium-zinc oxide (IZO) films were grown on glass substrates by rf magnetron sputtering using targets of 50 mol % In2O3-50 mol % In2O3(ZnO)(3) and In2ZnkOk+3 (k = 3, 4, 5, and 7) at room temperature and 300 degrees C. The difference in Zn content between the films and the sputter targets varied with the growth temperature. The structural, electrical, and optical properties of the IZO films were investigated as a function of Zn content. The crystal structure of IZO films grown at room temperature changed from amorphous to crystalline at a Zn content (Zn/(Zn+In)) of 68 at. %. IZO films grown at 300 degrees C using a target of 50% In2O3-50% In2O3(ZnO)(3) had a Zn content of 40 at. % and its x-ray diffraction peaks were matched with those of ITO. As the Zn content in IZO thin films grown at 300 degrees C increased from 40 to 74 at. %, the conductivity and optical band gap energy decreased. (c) 2006 American Vacuum Society.