Preparation and Characterization of Organic Electroluminescent Devices Using Low Molecule Compounds

摘要

The multi-layer organic electroluminescent devices(OELDs) were prepared on the patterened ITO substrates by the thermal evaporation method. Al or Li:Al was deposited onto the organic film as the anode electrode for the optical and electrical characterization. The current density and luminance were rapidly increased at the threshold voltage of 9V. The luminance and emission spectrum for the OELD samples with Al/CTM/Alq_3/TPD/ITO structures were found to be 430 cd/m~2 and 512nm at 17V showing green color emission. In contrast, the samples with Li:Al/Alq_3/TPD/CuPC/ITO multi-structures showed 508nm in the emission spectrum and 1736 cd/m~2 at 22V in the luminance. The increment of luminance may be ascribed to the improved efficiency of the recombination in the region of emission layer.