Luminescent Properties of Doped Organic EL Diodes Using Naphtalimide Derivative

Abstract

An organic dye was doped into the naphtalimide (NA) emission layers of some organic thin‐film electroluminescent (EL) diodes to evaluate those layers' EL emission intensity distribution and to understand their general emission properties. After a certain point, the nearer the doped layer was to the cathode, the weaker was its EL emission intensity; a steep drop‐off began at approximately 25 nm. This phenomenon may result from exciton dissociation, due to the presence of a Schottky barrier, at the emission layer/cathode interface.