Study of the growth conditions and characterization of CaCu2Ox and SrCu2Ox thin films

MCu2O2 (M = Ca, Ba, Mg, Sr) are promising materials for the development of new p-type transparent conductive oxide thin films. We report on a study of the growth conditions of MCu2Ox (M = Ca, Sr) thin films by injection MOCVD and on the characterization of their structural properties. By using calcium or strontium, and copper tetramethylheptanedionate as precursors dissolved in meta-xylene, cuprate films added with either calcium or strontium have been grown by injection MOCVD in the 450 °C–750 °C deposition temperature range. in factors for the deposition of films presenting good adherence and a high mirror reflection effect are the deposition temperature and the oxygen partial pressure during deposition. As-deposited Ca-based films are mainly composed of CaCu2O3 or a mixture of CaCO3, CaO, CuO and Cu2O, depending on the oxygen partial pressure and Sr-based films are composed of SrCO3, CuO. Different annealing under argon atmosphere has been performed in order to obtain the searched phase, which needs the reduction of copper in the 1+ oxidation state. We have succeeded to obtain SrCu2O2 phase by Rapid Thermal Processing but did not achieve to obtain the Ca-based compound.