Electroluminescence in Vacuum-Deposited Organic Thin Films

Abstract

Electroluminescence in organic thin films, ideally suited for large-area display devices, has been investigated by many researchers. The fabrication of thin-film EL cells using organic materials that exhibited high-EL efficiency has not yet been successful. Recently, Tang and VanSlyke reported a two-layer organic EL device with superior EL characteristics. /1/ Most recently, we proposed a new organic EL device with a three-layer structure; hole transport layer/emitting layer/electron transport layer./2, 3/ The introduction of hole and electron transport layers made possible the enhancement of the efficiency of hole and electron injection. Moreover, it made the selection of emitter materials free from the intractable technical problems of the fabrication of thin film EL devices; a polycrystalline emitting layer was sandwiched between two pin-hole free homogeneous, amorphous carrier transport layers in the resulting three-layer cells.KeywordsElectron InjectionTransport LayerDrive VoltageHole Transport LayerElectron Transport LayerThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.