Organic light-emitting devices basic structure

First, let us consider the basic structure of organic light-emitting diodes (Fig. 10). Not less than seven layers are used in a state-of-the-art device based on low-molecular-weight materials. The structure is derived from a five-layer concept (three organic layers and two electrodes) by Adachi et al. [6], who extended the original bilayer device of Tang and Van Slyke [5]. 

Organic polymers that emit light on the imposition of an electric field have commanded increasing attention in the last decade both for their scientific interest and as potential materials for electrooptical and optoelectronic applications. A number of reviews on electroluminescent polymers focusing the basic physics [1-5], synthesis and properties [6,7], device operation and materials [8-11], design and synthesis [12] blue emitting structures [13] have been published. Some books are also out on the subject [14—18]. 

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