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) device after previous illumination, the current through the phosphor layer will normally not be homogeneous, but increase from the cathodic side-where the electrons tunnel from-to the anodic side, due to multiplication. The positive charges that remain after the multiplication process cause a positive space charge that has been observed in various experiments and influences the efficiency. In this paper a simple numerical model is proposed for the calculation of charge transfer and light emission, in the case that multiplication takes place during a voltage pulse after previous illumination.