Temperature dependent electrical properties in ITO/TPD/Alq(3)/Al organic light-emitting diodes

Abstract

Temperature dependence of current-voltage-luminance characteristics in organic light-emitting diodes are studied in a device structure of ITO/TPD/Alq(3)/Al to understand an electrical conduction mechanism. The current-voltage-luminance characteristics are measured in the temperature range of 8Ksimilar to300K, and analyzed them using a hopping model with exponential trap distribution and Fowler-Nordheim tunneling. At low temperatures below 150K, the Fowler-Nordheim tunneling conduction mechanism is dominant. And we have obtained a zero field barrier height to be about 0.6similar to0.8eV