Morphological and optical characteristics of nanocrystalline TiO2thin films by quantitative optical anisotropy and imaging techniques

TiO 2 thin films were prepared by dc reactive sputtering with different ratios of oxygen to argon. The optical characteristics of the films were studied by birefringence imaging and optical anisotropic analysis using MetriPol. A clear trend of aggregation and structural variation of TiO 2 nanoparticles in the films can be seen using MetriPol optical anisotropic imaging. It was found that the optical characteristics of the TiO 2 thin films depend on the ratios of O 2 /Ar during sputtering of the films. The optical anisotropies are closely related to the structural feature of TiO 2 nanoparticles. Variation trends of TiO 2 film structures and optical characters have also been confirmed by FESEM observations and refractive index.