Structural characterization of sol-gel lanthanum cobaltite thin films

Abstract

The present paper is focused on structural, microstructural and compositional studies on nanophasic LaCoO₃ thin films obtained by the sol-gel route. The sample structure and microstructure were investigated by Glancing Incidence X-Ray Diffraction (GIXRD) and X-Ray microdiffraction (MicroXRD), whereas the surface and in-depth chemical composition was studied by X-Ray Photoelectron Spectroscopy (XPS). All the films are structurally homogeneous and not textured. A cubic-to-rhomboedral phase transition was detected after the thermal treatment at 800 °C. Evidence of residual stress was found by GIXRD patterns collected at different incidence angles. After thermal annealing at 1000 °C, only the crystalline La₂O₃ phase was detected.