New Red-Emitting CaY2S4:Eu Thin-Film Electroluminescent Devices

The CaY2S4:Eu thin-film electroluminescent (EL) device which emits a red EL due to the presence of Eu2+ luminescent centers was studied. CaY2S4:Eu thin films were fabricated by conventional electron-beam evaporation and post-deposition annealing. The CaY2S4:Eu thin-film EL device showed pure red electroluminescence with the commission internationale de l'ecairage (CIE) color coordinates x=0.67 and y=0.33. A luminance level of 350 cd/m2 was obtained under 1 kHz sinusoidal wave condition.