Influence of oligothiophene layer on PVK-based blue light-emitting diode

The alpha -sexithiophene, alpha -6T, was used as the hole injecting layer i n polymer-based electroluminescent (EL) device. The hole basis of injection mechanism at the ITO/dye-doped poly(N-vinylcarbazole) (PVK) layer was inve stigated on the Fowler-Nordheim tunneling theory. The tunneling mechanism o f holes is not applicable For the EL device that is fabricated in ITO/alpha -6T/dye-doped PVK/Al. We propose that the carrier injection barrier migrat es from electrode (ITO)/organic layer (dye-doped PVK) to organic layer(alph a -6T)/organic layer (dye-doped PVK). (C) 2001 Elsevier Science B.V. All ri ghts reserved.