TiO2 Thin Film’s Fabrication and Characterization in Response to Heat Treatment

In this study, substrates of glass were used for the deposition of transparent nanostructured thin layers of Titanium dioxide (TiO2) using a spin-coating system, and the solution was processed by sol-gel process. TiO2 sol and films were prepared with TTIP, hydrochloric acid, DI water, and ethanol. Here is the current work, these thin films were analyzed for various annealing treatments at 300 ◦C, 400 ◦C, 500 ◦C. The various attributes of films such as structural are described by X-ray diffraction (XRD) and RAMAN spectroscopy, morphology, and topography are studied by SEM and AFM, and optical properties are examined by UV-VIS spectroscopy. The direct energy bandgap estimated for the TiO2 films is 3.65ev, 3.71ev, and 3.75ev after heating at 300 ◦C- 400 ◦C- 500 ◦C. The initial crystalline phase (anatase) of TiO2 shows up after 400 ◦C for the four layers which are confirmed by XRD and RAMAN studies. At high temperatures, brookite and rutile crystalline phases are also found with the anatase phase. The attained films are translucent in the wavelength range between 380-700 nm and blurred in the 100- 380 nm range.