ABSTRACT
Organic light emitting devices (OLEDs) have attracted great attention as future devices for various kinds of displays since Tang et al. achieved a breakthrough in this field [1,2]. The key to their achievement is the use of organic multilayer structures. Another essential part of their success is the utilization of a metal organic complex, aluminum hydroxyquinoline (Alq), as the light-emitting material. Their reports triggered many studies on OLEDs in industry and academia. As a result, new classes of low molecular weight and polymer materials, which show efficient emissions from blue to red, have been developed.
