Transient behavior of organic thin film electroluminescence

Abstract

Transient behavior for an organic thin film electroluminescence (EL) cell with ITO/triphenylamine derivative/tris (8-hydroxyquinolino) aluminum (Alq)/Mg:Ag structure was observed by short voltage pulse measurements. The EL response was of the order of 10−7 s, and faster than that previously measured by Tang et al. [J. Appl. Phys. 65, 3610 (1989)]. In these measurements, we could observe carrier transit time. Then we concluded this carrier transit time should be attributed to that of electrons in Alq layer and the electron mobility of (5±2)×10−5 cm2/V s was obtained above the electric field of 1 MV/cm.