Electroluminescence and electron transport in a perylene dye

Charge carrier transport in vapor-deposited films of 1,6,7,12-tetraphenoxy-N,N' -bis-(2,6-diisopropylphenyl)-perplene-3,4,9,10-bis(dicarboximide) was investigated using two different methods, the time-of-flight (TOF) technique and time-resolved electroluminescence. Electron mobilities of 10(-5) cm(2)/V s were measured in the bulk using a time-of-flight technique. Hole transport was found to be dispersive and, thus, a transit time for holes could not be obtained. The above dye was also used to fabricate single layer light emitting diodes showing clearly visible red electroluminescence under ambient conditions. Our experiments on transit electroluminescence confirmed the measured electron mobility and ruled out the possibility that the transit time of holes is shorter than the time range investigated in our time-of-flight experiments. (C) 1997 American Institute of Physics.