Operation characteristics and degradation of organic electroluminescent devices

The degradation of the organic electroluminescent (EL) device is closely related to the physical and chemical stability of the organic thin films. Three important aspects are described: 1) an effect of glass transition temperature of hole transport materials on thermal stability of the device; 2) a role of interface layers at both the anode and cathode; and 3) an improvement of operation stability by doping technology. Considering the above points, an organic EL device was fabricated with a good operation performance: lifetime of longer than 3000 h at an initial luminance of 500 cd/m/sup 2/.