Synthesis of non-stoichiometric (LaO)CuS thin films by pulse laser deposition

We have attempted to control the photoluminescence spectrum of transparent p-type semiconductor (LaO)CuS to check possibilities of phosphor application using non-stoichiometric thin films prepared by pulse laser deposition method. Two kinds of samples are examined, one is the samples that contain the excess S and the other is the excess Cu. All samples are a single phase without impurities, regardless of heavily doping. Lattice constants for all samples don’t depend on the concentration of excess atoms. Perhaps, this is due to the nature of the layered materials. Introduction of excess atoms leads to change the photoluminescence spectra. The excess S and Cu have much effect on the red and the blue luminescence bands, respectively. We have succeeded in the tuning luminescence band of photoluminescence spectra.