Methods for studying the optical properties of transparent conducting oxides based on tin dioxide

Abstract

Background. Transparent conducting oxides are widely used in both functional electronics and smart glasses. The actual task is to identify the features of the technological process, as well as the key optical characteristics that affect the parameters of the conducting oxide. The purpose of this work is to analyze methods for studying the optical properties of transparent conducting oxides (methods based on dispersion relations; the Swanepoel method; the Chambuleiron method, etc.); analysis of experimentally obtained dependences of the absorption coefficient of samples differing in the level of doping. Materials and methods. The method of pointwise unconditional minimization is shown to be used to study the optical properties of transparent conducting oxides based on tin dioxide. The optical properties and thickness of the thin-film coating were determined by the envelope method. Results. The method of pointwise unconditional minimization is applied in the work, which allows to determine the thickness, the refractive index. The Tauc model was used to determine the absorption coefficient. Conclusions. Doping of transparent conductive coatings makes it possible to achieve a decrease in the optical absorption coefficient, which affects the increase in photon energy. Since tin dioxide with antimony is a semiconductor, the Fermi level is close to the conduction band, which explains the increase in the optical band gap.

Keywords

• transparent conducting oxide
• optical properties
• tauc model
• band gap
• absorption coefficient
• refractive index