Optical properties of ZnO films deposited by r.f. sputtering on sapphire substrates

The structural properties of the films were investigated by X-ray diffraction measurements. The morphology of the films was investigated with a scanning electron microscope. The optical reflectance and transmittance measurements were carried out in the wavelength range 0.3-0.8 μm. The Van der Pauw method was used to measure the electrical resistivity