SIMULATION AND MEASUREMENT OF MULTIPLICATION IN THIN-FILM ELECTROLUMINESCENT DEVICES WITH DOPED PROBE LAYERS

When a single voltage pulse is applied to an electroluminescent (EL) d evice after previous illumination, the current through the phosphor la ver will normally not be homogeneous, hut increase from the cathodic s ide-where the electrons tunnel from-to the anodic side, due to multipl ication. The positive charges that remain after the multiplication pro cess cause a positive space charge that has been observed in various e xperiments and in influences the efficiency. In this paper a simple nu merical model is proposed for the calculation of charge transfer and l ight emission, in the cast? that multiplication takes place during a v oltage pulse after previous illumination.