Direct-current-driven inorganic EL devices with rare-earth-doped ZnO layeres

Abstract

Direct-current (dc) inorganic EL devices were prepared with ZnO layers doped with a rare-earth (RE) as the luminescent center. The RE-ZnO layers were formed on a polycrystalline YSZ, MgO, or Al₂O₃ substrate by a dip-coating technique. The characterization indicated that the crystallinity and electric properties were strongly affected by a substrate type. The specific EL to Tm³⁺ and Eu³⁺ was observed from the dc-driven Tm-ZnO and Eu-ZnO layers, respectively.