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Updated: Mar 21, 2026
Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
The anisotropy of oxygen vacancy migration in SrTiO3
Juliane Hanzig1, Matthias Zschornak1, Erik Mehner1
1Institut für Experimentelle Physik, TU Bergakademie Freiberg, Leipziger Straße 23, 09599 Freiberg, Germany.
Abstract:
Oxygen migration in perovskites is well known to occur via vacancies along the TiO6 octahedron edges. Ionic conduction depends further on the orientation of the crystal in the electric field. To study the anisotropy in cubic SrTiO3 single crystals, temperature-dependent electroformation measurements ranging from 11 °C to 50 °C have been conducted for representative crystallographic directions within the crystal system. Electroformation of pure SrTiO3 follows an Arrhenius behavior, implying an ionic migration process of intrinsic oxygen defects. Activation energies E A for oxygen vacancy migration have been determined to 0.70 eV for [Formula: see text] and [Formula: see text] directions in contrast to 0.77 eV for [Formula: see text]. Mobility of oxygen vacancies is enhanced in [Formula: see text] compared to [Formula: see text] and [Formula: see text] by up to half an order of magnitude. A migration model based on atomistic migration paths and their multiplicities accounts for these experimental variations in mobility.
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