We have fabricated a highly efficient inverted bottom-emission organic light-emitting diode (IBOLED) based on an indiumtin oxide (ITO) bottom cathode deposited with an ultrathin 1 nm layer of Mg to promote electron injection. The threshold voltage of this IBOLED with a structure of ITO/Mg/Alq 3/NPB/WO3/Al was 4.2V and an efficiencies of 4.66 cd/A and 1.51 Im/W were achieved at an operational voltage of 8.9V and a brightness of 940cd/m2. In comparison with an ITO/Alq3 bottom cathode composition, a reduction in drive voltage from 13.8 to 7.8V in voltage was obtained at 1 mA/cm2. A charge-transfer dipole model is proposed to rationalize the enhanced electron injection.
|Number of pages||3|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Issue number||6 A|
|State||Published - 28 Jun 2006|
- Electron injection
- Indium tin oxide (ITO)
- Inverted organic light emitting device (IOLED)