Effects of $Ar//O_2$ Gas Ratio on the Properties of the $Zn_{0.9}Cd_{0.1}O$ Films Prepared by DC Reactive Magnetron Sputtering

$Zn_{0.9}Cd_{0.1}O$ ternary alloys have been grown on the sapphire substrates by using the direct current (dc) magnetron sputtering. X-ray diffraction measurements showed that all samples were highly oriented films along the c-axis perpendicular to the substrate surface. X-ray diffraction confirmed that the crystal quality of $Zn_{0.9}Cd_{0.1}O$ films can be controlled by changing the gas ratio of $Ar//O_2$. The optical properties of these films have been investigated by means of the optical transmittance and the low-temperature photoluminescence spectra. It was found that the optical band gap of the deposited films can be tuned by growth parameters. The luminescence processes are considered in the terms of alloy fluctuation.