The annealing behaviour of oxygen vacancies introduced by epitaxial growth of DyScO3 or SrTiO3 films on SrTiO3 substrates was studied by positron annihilation. Many oxygen vacancies (VO) were introduced near the interface in SrTiO3 substrates when 10 nm DyScO3 or 20 nm SrTiO3 films were grown by pulsed laser deposition at 10-2 Torr or 10-6 Torr oxygen pressure, respectively. Post-annealing in oxygen ambient could partly compensate those vacancies in the SrTiO3/SrTiO3 samples while no vacancy compensation was observed in the SrTiO3/DyScO3 or SrTiO3/DyScO3/SrTiO3 heterostructures. This suggests that epitaxial DyScO3 films can be used as passivation layers to suppress the diffusion of oxygen vacancies.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Acoustics and Ultrasonics
- Surfaces, Coatings and Films