Electroluminescence near interfaces between (Ca,Sr)TiO3:Pr phosphor and SnO2:Sb transparent conductor thin films prepared by sol-gel and spin-coating methods

Chemically stable oxide inorganic electroluminescent devices, in which thin-film layers of Ca0.6Sr0.4TiO3:Pr phosphor and SnO2:Sb transparent conductor are alternately stacked, were prepared by sol-gel and spin-coating methods. Electroluminescence was observed by applying either ac or dc voltages to the devices. The device showed 1 cd m−2 at 21 V corresponding to 0.1 MV cm−1 and 113 cd m−2 at 44 V when 5 kHz ac voltage was applied. The luminance increased with increasing the number of SnO2:Sb layers. Intense electroluminescence occurred near Ca0.6Sr0.4TiO3:Pr/SnO2:Sb interfaces when Ca0.6Sr0.4TiO3:Pr was negatively polarized and SnO2:Sb was positively polarized. The mechanism of electroluminescence near Ca0.6Sr0.4TiO3:Pr/SnO2:Sb interfaces was discussed based on the luminescence and semiconducting properties of Ca0.6Sr0.4TiO3:Pr.