An investigation was made of O-vacancy ordering in epitaxial (La0.5Sr0.5)CoO3–δ thin films which were grown by sputter deposition onto (001)LaAlO3 or (001)SrTiO3. After annealing at 500C, under O partial pressures greater than those used during deposition, the films transformed into a long-range O-vacancy ordered structure with orthorhombic symmetry. The observed orientation variants of the O-vacancy ordered structures were different for the 2 substrates.

 Impact of Stress on Oxygen Vacancy Ordering in Epitaxial (La0.5Sr0.5)CoO3–δ Thin Films. D.O.Klenov, W.Donner, B.Foran, S.Stemmer: Applied Physics Letters, 2003, 82[20], 3427-9