Feasibility of TFEL application of Ce-doped CaGa2S4 and SrGa2S4 films prepared by flash evaporation method Original Research Article

Ce-doped CaGa2S4 and SrGa2S4 thin films were prepared for the first time by the flash evaporation method. The films were characterized before and after annealing in H2S(10%)+Ar gas stream by measuring photoluminescence and absorption spectra, X-ray diffraction and electron probe micro analyses. X-ray diffraction curves and absorption spectra before annealing show amorphous behaviour, whereas the annealing leads to a significant crystallization and improves the stoichiometry of the films. Based on the performance data obtained from dispersive type EL cells using CaGa2S4:Eu powder together with photoluminescence property comparison between CaGa2S4:Eu and CaGa2S4:Ce powders, the annealed films prepared by flash evaporation can be considered to become one of the candidates for TFEL flat panel devices.