Growth of LaCoO3 thin films from β-diketonate precursors

LaCoO3 thin films have been deposited in a flow-type atomic layer epitaxy (ALE) reactor from La(thd)3 and Co(thd)2, (thd=2,2,6,6-tetramethyl-3,5-heptadione) precursors using ozone as oxygen source. Films were grown on both soda lime and Corning glass substrates in the temperature range of 200–400°C. Profilometry, X-ray diffraction, Rutherford backscattering spectroscopy and X-ray photoelectron spectroscopy measurements were used to determine the thickness, crystallinity and stoichiometry of the films. The films grown below reactor temperatures of 400°C were X-ray amorphous, but became crystalline LaCoO3 when annealed at 600°C in air. Besides LaCoO3, the binary oxides (La2O3 and Co3O4) were also grown as thin films.