ABSTRACT
Bandgap plays an important role in photonic device and solar cell applications. Bandgap of TiO2 depends on its phases (amorphous, anatase, ruitile and brookite). This chapter discusses TiO2 thin-film preparation using sol–gel spin coating process for the benefit of future researchers. Titanium iso-propoxide is mixed with ethanol and acetic acid to get precursor solution of TiO2. Prepared solution is spin-coated on clear glass substrate for 15 sec at 5000 rpm to form as-deposited TiO2 thin films, which are further annealed at different temperatures. Optical and material characteristics are also studied for as-deposited and annealed samples. Optical indirect bandgap discussed in this chapter is in line with other reported data, which also suggests decrease in bandgap due to increase in annealing temperature.
