Efficient deep blue emitters for organic electroluminescent devices

Abstract

Highly efficient deep blue organic light emitting devices have been fabricated with a 4-(styryl)biphenyl-core based fluorescent dopant (SK-1) in the wide band gap 2-methyl-9,10-di(1-naphthyl)anthracene (alpha,alpha-MADN) host system which achieved an electroluminescence efficiency of 5.0 cd/A and an external quantum efficiency of 4.2% at 20 mA/cm(2) with a saturated blue Commission Internationale de l'Eclairage coordinates of (0.15, 0.14) and a half-decay lifetime of 8000 h at an initial brightness of 100 cd/m(2). The current efficiency and electroluminescent color of SK-1 doped devices have been shown to be essentially immune to drive current density. (C) 2007 American Institute of Physics.