The Effects of O2:N2 Gas Ratios on Structural, Optical, Electrical Properties of TiOxNy Thin Film Deposited by Reactive DC Magnetron Sputtering

Abstract

In this work, titaniumoxynitride (TiOxNy) thin films were deposited on glass slide substrates by using reactive dc magnetron sputtering technique. The reactive gas ratios between O2and N2were studied in the range of 15-30% with a constant of Ar gas at 110 sccm and a time of 120 minutes. Microstructure, optical, and electrical properties of TiOxNythin films were analysis by using SEM, AFM, GIXRD, UV-VIS spectrophotometer, and 4-point probe measurements. We found that the thickness of the films decreases from 1.0 to 0.8 μm by increasing of O2gas ratios. The TiOxNythin films have smooth surface related to small nanograin size. The roughness of the films slightly decreases when O2gas ratios increase. From optical transmission spectra, we observed that the transparent of the films increases with different O2gas ratio and shifts the band gap from 2.67 to 3.32 eV. The resistivity of the films obviously increases from 3.04 x 10-3Ω-cm to 5.45 Ω-cm depending on O2gas ratio. These results indicate the phase changes of the TiOxNyfilms from metallic to oxide phases. The XRD spectra show poor crystalline TiN (220) and TiO2(021) at 15% of O2ratio and then the films become amorphous structure by increasing the O2gases. The O2:N2gas ratios also affects to the different concentration of oxygen and nitrogen into the TiOxNythin films that lead to the various structural, optical and electrical properties.