Pressure dependence of electrical and optical characteristics of Alq(3) based organic electroluminescent diodes

Organic electroluminescent diodes based on thin organic layers are one of t he most promising next-generation systems for the backlighting of liquid cr ystal screens. In the literature, conduction has been interpreted in terms of tunneling or as a space charge limited process. To clarify this point we carried out an experimental study of the electrical and optical characteri stics, as a function of the applied voltage, for different hydrostatic pres sures. Results show that tunneling is the dominant mechanism which controls the organic light emitting diodes efficiency. (C) 1999 American Institute of Physics. [S0021-8979(99)00501-0].