Electroluminescence in thin-film CaS:Ce

Abstract
We report a double insulated CaS:Ce thin-film electroluminescent (EL) device which emits a bright green EL due to Ce3+ luminescent centers, being characteristic of parity allowed 5d–4f transitions. A brightness level of 500 cd/m2 and emission efficiency of 0.11 lm/W have been obtained under 5-kHz sinusoidal voltage excitation. The CaS:Ce thin film has been fabricated by coevaporation of CaS and sulfur.