Deposition of Co Doped TiO2 Films Using Sol Gel Spin Coating Technique and Investigation of Band Gap

Abstract

TiO2 is a wide band gap semiconductor and have high refractive index, wide wavelength spectrum and high optical transmission. In this present study, 3 layered, undoped, % 1 and % 5 (molar ratio) Co doped films were deposited on glass substrate by repeating steps via sol-gel Spin Coating technique. Produced films were annealed at in air. The thickness of films obtained about 650 nm by spectroscopic ellipsometry (SE). The optical properties have been characterized by UV-Vis spectrophotometer. By using the Tauc equations band gap values were calculated. The effect of doping ratio was investigated. The optical band gap (OBG) varies between 3.19 and 2.79 eV. It observed that OBG values of TiO2 films are inversely proportional with increase of dope ratio.