Analysis of electoluminescence mechanisms in N,N′-disphenyl-N,N′-bis(3-methylphenyl)-1,1′-disphenyl-4,4′-diamine/hydroxyquinoline aluminum bilayer organic light-emitting diode by bipolar hopping conduction

We proposed a one-dimensional model for N,N'-disphenyl-N,N'-bis(3-methylphenyl)-1,1'-displlenyl-4,4'-diamine/hydroxyquinoline aluminum (TPD/Alq3) bilayer organic light-emitting diode (OLED) based on hopping conduction, which is not different from the conventional continuous model for semiconductors and metals. We assumed that each emitting molecule corresponds to a hopping site according to the actual charge transfer between the adjacent molecules. Time change of carrier. field. and exciton distribution were calculated. Both carrier mobility of Alq3 and barrier heights for each carrier were derived from experimental data.