The impurity effects on OLEDs via transient electroluminescence analysis

In this report, the influences of the impurities to the performance of OLEDs were discussed. The removing of the impurities improve the carrier injection ability and also carrier transporting behavior, resulted in the improvements of device efficiency. The transient electroluminescence (TREL) analysis was also used to discuss the carrier transporting behavior of OLEDs with various material purification times. The change of the delay time and rise time showed that the carrier injection ability was improve and the carrier transporting characteristic became more non-dispersive after the purifications.