Efficient Blue Emitting CaGa_2S_4:Ce Thin-Film Electroluminescent Devices Prepared by Two Targets Pulse Electron Beam Evaporation Method

Abstract

CaGa_2S_4:Ce thin films were prepared by two targets pulse electron beam evaporation(EBE)method. As the source material, CaS:CeF_3 and Ga_2S_3 were used. This method can easily control electron-beam-irradiation times to the each targets. So the composition in the thin filmscould be also controled. And thin film electroluminescent(TFEL)devices exhibited high efficient blue emittion. Maximam luminance was 160cd/m^2 at 1kHz sinusoidal wave voltage and 16cd/m^2 at 20μs, 50Hz pulse wave voltage.