A study of Ti-doped WO3 thin films using comparative theoretical and experimental approach

Metal oxides like Tungsten Oxide (WO3) are well documented and characterized in the literature, with uses in darkening windows and mirrors, flat computer displays, solar panel cooling, and sensors (of interest in this study). Ti doping of WO3 is less documented and the focus of this study. Sample thin films of pure WO3 and varyingly Ti doped WO3 were prepared using Radio Frequency magnetron sputtering (RF) (13.56 MHz) to grow thin films on a silicon substrate. This study aims to compare multiple Ti doping percentages in WO3 theoretically and then compare with experimental data taken from thin films of various Ti doping levels grown at temperatures ranging from room temperature to 400 0°C. Characterization of the materials was to be conducted using Fourier Transform Infrared Spectroscopy, Raman Spectroscopy, X-ray diffraction, and other theoretical and simulated approaches. Theoretical calculations optimized Ti doping at somewhere between 6.25% and 12%. Experimental data indicates that under the given growing conditions optimal Ti doping is 5%. The percentage of Ti may be able to be increased and the material retain desired characteristics with an increased growth temperature above 400 0°C as annealing samples post-growth has no positive impact on the thin film structure