ZnO films on Al2O3 substrates were grown using a pulsed laser deposition method. Through photoluminescence (PL) and X-ray diffraction (XRD) measurements, the optimum growth conditions for the ZnO growth were established. The results of the XRD measurements indicate that ZnO films were strongly oriented to the c-axis of the hexagonal structure and epitaxially crystallized under constraints created by the substrate. The full width half maximum for a theta curve of the (0002) peak was 0.201 degrees. Also, from the PL measurements, the grown ZnO films were observed to give free exciton behaviour, which indicates a high quality of the epilayer. The Hall mobility and carrier density of the ZnO films at 293 K were estimated to be 299 cm(2)/ V s and 8.27x10(16) cm(-3), respectively. The absorption spectra revealed that the temperature dependence of the optical band gap on the ZnO films was E-g(T)=3.4393 eV-(5.30x10(-4) eV/K)T-2/(367+T).

Keywords: ZnO thin films; pulsed laser deposition; optimum growth conditions; optical band gap; Hall mobility; carrier density