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 angstrom)/ silver (150 angstrom). 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) (Alq(3)) 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-diphenyl-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. (c) 2004 Elsevier B.V. All rights reserved.