Thickness dependence of the properties of transparent conducting ZnO:Zr films deposited on flexible substrates by RF magnetron sputtering

Transparent conducting zirconium-doped zinc oxide(ZnO:Zr)thin films with high transparency,low resistivity and good adhesion were successfully prepared on water-cooled flexible substrates(polyethylene glycol terephthalate,PET)by RF magnetron sputtering.The structural,electrical and optical prooerties of the films were studied for different thicknesses in detail.X-ray diffraction(XRD)and scanning electron microscopy(SEM)revealed that all the deposited films are polycrystalline with a hexagonal structure and a preferred orientation perpendicular to the substrate．The lowest resistivity achieved is 1.55×10-3 Ω·cm for a thickness of 189 nm with a Hall mobility of 17.6cm2/(V·s)and a carrier concentration of 2.15×1020cm-3.All the films present a high transmittance of above 90％in the wavelength range of the visible spectrum.