INFLUENCE OF ANTHRECENE DOPING ON ELECTRICAL AND LIGHT-EMITTING BEHAYIOR OF 8-HYDROXYQUINOLINE-ALUMINUM BESED ELECTROLUMINESCENT DEVICES

In order to improve EL performance, anthracene was doped into the 8-hydroxyquinoline-aluminum (Alq$^3$) light-emitting layer of organic double layered EL cells. The EL cells were fabricated on ITO glass substrates by vacuum deposition. Doping of anthracene to the light-emitting $Alq^3$layer was performed by means of co-evaporation. The doping concentration was changed in the range of 5 to 30 wt.%. It was confirmed that anthracene doping of appropriate concentration increased the available current density and brightness of the EL cells. Carrier mobility of the $Alq^3$ layer was measured by time of flight method. The influence of anthracene doping on the cell performance was discussed.