Room temperature deposition of XRD-amorphous TiO2 thin films: Investigation of device performance as a function of temperature

In this study, TiO2 thin films were fabricated by radio frequency sputtering at room temperature in pure Ar atmosphere starting from a 6 in. TiO2 target. The thickness of the films was controlled by deposition time and the effect of Ar sputtering pressure on the characteristics of TiO2 thin films was evaluated. Surface morphology and optical properties of TiO2 films were investigated using X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and UV-Vis spectrophotometry. Also, the refractive index and extinction coefficient of films were inferred by fitting spectrophotometric data. Schottky diode were fabricated by evaporation of Ni on TiO2 films. Current-voltage (I-V) measurements of Ni/TiO2 films showed that the rectifying properties of the device improves with the increasing of TiO2 film density and thickness. Therefore, the best I-V characteristic of the device was investigated depending on the temperature. Also, Ni/n-TiO2/p-Si/Al devices were fabricated to understand their transport mechanism.