A semitransparent cathode of indium tin oxide (ITO)/Ag/ITO was developed as a resonant tunneling double barrier structure for transparent organic light-emitting diodes. A weak negative differential resistance was observed in devices using a 100 nm thick ITO/Ag/ITO layer as a cathode in combination with a thin LiFAl layer. The current injection of devices was dominated by resonant tunneling, which induced no luminance at low voltage. This was achieved by employing an e-beam evaporated ITO/Ag/ITO cathode due to the double quantum barriers of ITO and the quantum well of Ag. The authors also applied the multilayer cathode to small molecule devices, which showed the same resonant tunneling currents.
Bibliographical noteFunding Information:
The authors offer special thanks to Jun Yeob Lee from Dankook University for his valuable advice. This work was supported by the Brain Korea 21 (BK21) fellowship program at Korea’s Ministry of Education.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)