Published online by Cambridge University Press: 01 February 2011
Conventional organic light-emitting diodes (OLEDs) having electrically doped carrier injection and transport layers with high conductivity exhibit extremely low driving voltages, which is due to the formation of radical anions and cations and ohmic contacts at the electrode interfaces. We report here an inverted OLEDs with indium-tin-oxide (ITO) bottom contact as cathode for electron injection. The device comprise an intrinsic 8-tris-hydroxyquinoline aluminum (Alq3) emission layer sandwiched in between n- and p-doped charge transport layers.