Interrelation of epitaxial strain and oxygen deficiency in La 0.7 Ca 0.3 MnO 3−δ thin films

Abstract

The interrelation between the epitaxial strain and oxygen deficiency in La0.7Ca0.3MnO3-{\delta} thin films was studied in terms of structural and functional properties. The films with a thickness of 1000{\AA} were prepared using a PLD system equipped with a RHEED facility and a pyrometric film temperature control. The epitaxial strain and the oxygen deficiency in the samples were systematically modified using three different substrates: SrTiO3, (LaAlO3)0.3-(Sr2AlTaO6)0.7 and LaSrAlO4, and four different oxygen pressures during film growth ranging from 0.27mbar to 0.1mbar. It could be demonstrated that the oxygen incorporation depends on the epitaxial strain: oxygen vacancies were induced to accommodate tensile strain whereas the compressive strain suppressed the generation of oxygen vacancies.