Controlling the optical properties of nanostructured TiO2 thin films

We have studied the optical properties of nanostructured TiO2 films and demonstrated the ability to tune the refractive index of the material over a wide range. The nanostructured films are fabricated using glancing angle deposition, which provides the ability to precisely control the density of the deposited film. Film morphology was examined using scanning electron microscopy and the films were optically characterized by polarized-reflectance measurements. A simple isotropic homogeneous model, which is shown to be a good approximation of the film, is used to determine the optical constants from the reflectance measurements. Improvements to the model are suggested. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim