| 초록 |
The interface dipole energies between interfacial layers with different thicknesses coated on indium tin oxides (ITOs) and 4,4'-bis[N-(1-naphtyl)-N-phenyl-amino]biphenyl were determined byultraviolet and synchrotron radiation photoemission spectroscopy. The interface dipole energy increased as a function of interfacial layer thickness up to 4 nm. After O2 plasma treatment on thick-metal (＞ 4 nm) coated ITO, the work function and interface dipole energy increased. In thin-metal (＜ 2 nm) coated ITO, no change in the interface dipole energy was found though the work function increased. Thus, the O2 plasma treated thin (＜ 2 nm) interfacial layer reduced the hole injection barrier. Using this concepts, the organic light emitting diodes using transition-metal-oxide based hole injection layer were fabricated. |
