Organic electroluminescent devices using alkaline-earth fluorides as an electron injection layer

Abstract

We investigated the properties of organic electroluminescent (EL) devices using alkaline-earth fluorides as an electron injection layer, and found that the alkaline-earth fluorides are desirable materials to reduce the turn-on voltage of the EL devices with Al cathode. In the devices using the fluorides as the electron injection layer, we found that the turn-on voltage can be associated with electronegativity of metal ion of the fluoride; the fluoride with a low electronegativity metal ion results in lowering the barrier height at the organic/Al interface and enhanced the electron injection.