Avaliação de propriedades ópticas e espessura de filmes finos de TiO2 a partir do espectro de transmitância

Abstract

TiO2 thin films have been successfully used in solar cells, smart windows, photochromic and electrochromic windows and also as photocatalytic coatings. In this work, TiO2 thin films were deposited by magnetron sputtering on a glass substrate and their optical properties, thickness, microstructure and photocatalytic properties were evaluated. Film thicknesses and band gaps were determined by the Swanepoel method using the envelopes in the transmission spectrum and also the PUMA computational method. The films were analyzed by X-ray Diffraction (XRD), Energy Dispersive X-ray Spectroscopy (EDS), Scanning electron microscopy (SEM) and optical analysis. SEM measured thicknesses were compared to those obtained using the optical methods. The PUMA method proved advantageous for thickness determination of thin films, particularly when the interference fringes are not evident in the transmission spectrum. In addition, film thicknesses determined using the PUMA method were in better agreement with SEM measurements than those determined by the Swanepoel Method.