Polymer light emitting diodes: new materials and devices

Single layer polymer light emitting diodes (LEDs) are ideal candidates for practical applications due to their easy processing conditions. However, low quantum efficiency of light generation is often obtained due to imbalanced charge injection and transport of holes and electrons. In this paper we report new conjugated polymers with electron deficient oxadiazole moieties as side-chains. These polymers have shown at least an order of magnitude increase in electroluminescence efficiencies and better charge injection properties compared to their corresponding conjugated backbone polymers. In addition, novel patterned LED device structures which emit in geometries with features into the submicron range will be presented. Finally, issues regarding integration of polymer transistors with organic LEDs will be discussed. (C) 1999 Elsevier Science B.V. All rights reserved.