New challenges on gallium-doped zinc oxide films prepared by r.f. magnetron sputtering

Abstract Gallium-doped zinc oxide films were prepared by r.f. magnetron sputtering at room temperature as a function of the substrate–target distance. The best results were obtained for a distance of 10 cm, where a resistivity as low as 2.7×10 −4 Ω cm, a Hall mobility of 18 cm 2 /Vs and a carrier concentration of 1.3×10 21 cm −3 were achieved. The films are polycrystalline presenting a strong crystallographic c -axis orientation (002) perpendicular to the substrate. The films present an overall transmittance in the visible part of the spectra of approximately 85%, on average.