Structural, optical and electrical characterization of Ga-Mg co-doped ZnO transparent conductive films

The transparent conducting Ga-Mg co-doped ZnO films were prepared on glass substrates by radio-frequency (rf) magnetron sputtering. The effect of growth temperature on structural, morphological and optoelectronic properties of the films was investigated by XRD, XPS, SEM, UV-visible spectrophotometer and four-point probe. The results show that all the films are polycrystalline and (0 0 2) oriented. The growth temperature significantly affects the structure and optoelectronic properties of the films. The film deposited at the growth temperature of 270 degrees C has the largest grain size of 52.38 nm, the minimum tensile stress of 0.037 GPa, the highest average visible transmittance of 89.39%, the lowest resistivity of 1. 52 x 10(-3) Omega.cm and the maximum figure of merit of 5.87 x 10(3) Omega(-1).cm(-1). Furthermore, the optical band-gaps were determined by extrapolation method and observed to be in the range of 3.36-3.59 eV. (C) 2017 Elsevier B.V. All rights reserved.