Donor-doping effect in BaTiO3 ceramics using positron annihilation spectroscopy

Temperature-dependent measurements using positron lifetime spectroscopy (PLS) were carried out to study various defects in polycrystalline donor doped BaTiO3 (BT) samples. Annealing under different donor-doping level of La and Y were performed. At high doping level, it was found that with increasing doping level the average lifetime increases. This is attributed to the interplay of complexes containing oxygen vacancies V-O and other vacancies, such as V-Ba, V-Ti as well as grain boundaries. (C) 2003 Elsevier Ltd. All rights reserved.