Investigation of inhomogeneity of TiO2 thin films using spectroscopic ellipsometry

Abstract

Titanium dioxide thin films have been deposited on silicon wafers (100) substrates by pulse DC reactive magnetron sputtering. The spectroscopic ellipsometry is the method use to determine the degree of inhomogeneity of titanium dioxide thin films. The effect of operating pressure on the micro-structural and optical properties of inhomogenity Titanium dioxide thin films were characterized by grazing-incidence X-ray diffraction, spectroscopic ellipsometry, field emission scanning electron microscope and high resolution transmission electron microscopy. The optical properties of the films were examined by variable-angle spectroscopic ellipsometer. Several spectroscopic ellipsometry models, categorized by physical models, were proposed based on the 'simpler better' rule and curve-fits, which were generated and compared to experimental data using regression analysis. It has been found that the triple-layer physical model with the Cody-Lorentz dispersion model offered the most convincing result. Titanium dioxide thin film was found inhomogeneous and a more detailed analysis of high resolution transmission electron microscopy and field emission scanning electron microscope are discussed.