Color-saturated and highly efficient top-emitting organic light-emitting devices

Color-saturated and highly efficient top-emitting organic light-emitting devices (OLEDs) were developed. The device structure studied was glass/reflective silver/indium-tin oxide (ITO; 50, 75, 100, 125 and 150 nm, respectively)/organic electroluminescent (EL) stack/calcium (200 Å)/ silver (150 Å). By changing the thicknesses of ITO from 50-150 nm in the reflective ITO/Ag anode, different emissive colors from bluish green to orange can be obtained from aluminum tris(8-hydroxyquinoline) (Alq3) emitter. By using 2-{2-(t-butyl)-6-[(E)-2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinoline-9-yl)-1-ethenyl]-4H-4-pyranliden}malonitrile (DCJTB), 10-(1,3-benzothiazol-2-yl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinoline-11-one (C-545T) and p-bis(p-N,N-di-phenyl-aminostyryl)benzene (DSA-ph) as dopants, highly saturated red, green, and blue (RGB) emissions with Commission Internationale de L'Eclairage chromaticity coordinates of (0.64, 0.36), (0.14, 0.75) and (0.14, 0.08) were obtained, respectively.