Transparent and conductive Al-doped ZnO films have been prepared by simultaneous RF and DC
magnetron sputtering. In order to study the properties of the Al-doped ZnO films, we performed Xray
diffraction, X-ray absorption spectroscopy, temperature dependence of electrical resistance and Hall
measurements, as well as optical transmission spectroscopy. The results revealed that all the samples
were polycrystalline with a strong preferential c-axis orientation. A minimum resistivity of 7:13*10-3Ωcm was obtained, and a metallic-type conducting behavior was observed for the film at 50 W. Our
present work suggests that the electrical transport property of the Al-doped ZnO films is closely related to
the crystallinity. A large number of defects due to poor crystallinity and the induced stress field are able
to immobilize the free carrier thereby reducing the conductivity.