Abstract: Thin films of the perovskite manganese oxides with three oxidation states of Mn3+-Mn4+-Mn5+ were successfully prepared on the SrTiO3(001) substrates by off-axis radio frequency magnetron sputtering. The structure of the thin film is cubic with Pm3m space group, consisting of La3+, Ca2+ and K+ three kinds of ions occupied in A sites and three oxidation states of manganese in B sites, respectively. The as-made La1-x-yCaxKyMnO3 thin films are oriented multi-crystal epitaxial forms, as tested by the high energy(18 kW) X-ray diffraction and D8 discover X-ray diffraction with General Area Detector Diffraction System(GADDS). The AFM photographs show that the surface of the films is smoothy and the root-mean-square(RMS) increases along with the increase of the thickness. The results of the surface photovoltage(SPV) spectroscopy shows relatively strong signal, indicating the ability for the conversion of photoelectricity.

Key words: Three oxidation state, Epitaxial film, Photovoltage