Oxygen Vacancy Motion in Perovskite Oxides

Abstract

Using electron paramagnetic resonance, the motion of oxygen vacancies within the oxygen octahedron in perovskite BaTiO 3 is observed via the alignment of oxygen vacancyrelated defect dipoles induced by bias/heat combinations. The vacancy motion is found to have an activation energy of 0.91 eV, in excellent agreement with that predicted. It is found that the onset of resistance degradation is also concurrent with oxygen vacancy motion. This result spectroscopically demonstrates that oxygen vacancy migration in the lattice is likely responsible for the observed degradation.