ORGANIC ELETTROLUMINESCENT DEVICE WITH LOW OXYGEN CONTENT

摘要

An organic electroluminescent device comprising a cathode and an ode and, disposed therebetween, an organic layer has oxygen atoms accumulated near the int rface of the organic layer and the cathode in a maximum concentration of less than about 6 t%, the maximum concentration being expressed in terms of the peak maximum of a sputte profile of the Ois concentration near the interface of the organic layer and the cathode meas red by means of X-ray photo-electron spectroscopy. Having such an unprecedented low m imum oxygen concentration, the EL device has an extended operational lifetime.