Annealing effect on magnetic and electrical properties of epitaxial La0.8MnO3−δ thin films grown by chemical vapor deposition

A new liquid source metalorganic chemical vapor deposition process has been developed in order to control precisely the amount of precursors vapors that is produced. Films of self-doped La0.8MnO3−δ have been deposited on LaAlO3 (012) substrates. X-ray diffraction measurements reveal an epitaxial growth. The as-deposited films exhibit both a ferromagnetic (Tc=200 K) and a metal–insulator (Tρ=130 K) transition. Postannealing experiments have been carried out and the results indicate the resistivity is considerably reduced, the temperature of transitions is raised to 320 K, and a magnetoresistance Δρ/ρ0=20% per tesla is obtained at 300 K in the 0–2 T range.