Structural and optical properties investigation of DC magnetron sputtered β-TiO2 thin film

Thin films of monoclinic titanium oxide phase (β-TiO2) have been grown on glass substrate using DC magnetron sputtering technique. The effect of oxygen conditions on the films stoichiometry, growth rate, structure, molecular mode of vibration and optical properties has been investigated. An improvement in stoichiometric ratio (O/Ti) has been observed with the increase of oxygen content in the synthesized chamber. XRD patterns demonstrated the polycrystalline nature of the deposited films with (2¯11) preferential orientation of β-TiO2 phase. In the FTIR analysis, a dominant peak at 868 cm−1 wavenumbers corresponding to the longitudinal optical (LO) mode of monoclinic TiO2 phase was observed at 10% oxygen condition. It shifted to 880 cm−1 wavenumbers at higher oxygen fractions, illustrated the rise of oxygen concentration in the grown films. The influence of various oxygen conditions on transmittance/extinction coefficient, band gap and refractive index of TiO2 (B) phase is reported.