Dynamics of oxygen vacancies and defect complexes in the perovskite oxide structure

A comprehensive description of the methodology necessary to completely characterize and analyze the concentration and kinetic parameters related to oxygen vacancies in oxide dielectrics is presented. An emphasis is made on the characterization of defect complexes formed by the nearest neighbor pairing of acceptor dopant or impurity ions with oxygen vacancies. By using a range of experimental techniques backed by a thorough re-analysis of studies available in the literature, a new model for the local interaction of oxygen vacancies with acceptor ions is presented.;An important conclusion of the presented material is that the method used to measure transport processes related to conductivity has a critical influence on the kinetic parameters that are obtained. General expressions for vacancy mobility are typically applied over wide ranges of experimental and material parameters. As depicted in Figure 1, however, the measurement technique that is used will typically probe orders of magnitude in length scale.;The interaction of oxygen vacancies with their local surroundings is influenced by changes in temperature, defect concentration, and applied electric bias. By defining an oxygen vacancy potential energy landscape, a unified model for oxygen vacancy mobility can be derived that explains the dynamics of oxygen vacancies at all measurable length scales.