White Organic Light-emitting Devices using the Blue and Green Fluorescent Emitting Layer Structure Incorporating with Red Phosphorescent Emitting Layer

摘要

Efficient white organic light-emitting diodes are fabricated with the blue and green fluorescent incorporating red phosphorescent emitting layer. The blue, green and red emitting layer consist of 1,4-bis(2,2-diphenyl vinyl)benzene (DPVBi), tris (8-hydroxyquinoline) aluminium (Alq) and the bis(l-(phenyl)isoquinoline)iridium(III)acetylanetonate [Ir(piq)_2(acac)] doped into 4,4(-N,N)-dicarbazole-biphenyl(CBP) host, respectively. The devices were made of ITO/ m-MTDATA (40 nm)/ NPB (10 nm) /DPVBi (8 nm)/ CBP: Ir(piq)_2(acac) x% 5nm/ Alq (50 nm )/ LiF (1 nm) / Al (200 nm). The electroluminescent (EL) spectra exhibit three peaks at 456, 520 and 620 nm, resulting in white light-emission with the Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.37, 0.44) at 4V to (0.23, 0.30) at 13V when x is 4, while the device shows the current efficiency of 4.0 cd/A at 6V, and its maximum luminance is 21660 cd/m~2 at 13V, respectively.