Recent progress of molecular organic electroluminescent materials and devices

Electroluminescent devices based on organic materials are of considerable interest owing to their attractive characteristics and potential applications to flat panel displays. After a brief overview of the device construction and operating principles, a review is presented on recent progress in organic electroluminescent materials and devices. Small molecular materials are described with emphasis on their material issues pertaining to charge transport, color, and luminance efficiencies. The chemical nature of electrode/organic interfaces and its impact on device performance are then discussed. Particular attention is paid to recent advances in interface engineering that is of paramount importance to modify the chemical and electronic structure of the interface. The topics in this report also include recent development on the enhancement of electron transport capability in organic materials by doping and the increase in luminance efficiency by utilizing electrophosphorescent materials. Of particular interest for the subject of this review are device reliability and its relationship with material characteristics and interface structures. Important issues relating to display fabrication and the status of display development are briefly addressed as well. (C) 2002 Elsevier Science B.V. All rights reserved.