A green top-emitting organic light-emitting device with single-mode resonance and improved performance by using WO3 capping layer

Abstract

A top-emitting organic light-emitting device (TOLED) with an architecture of Ag/Wo3/4,4'-bis[N -(1-naphthyl-1)-N-phenyl-amino]-biphenyl/tris-(8-hydroxyquinoline)aluminium(Alq3)/LiF/Al/semitransparent Ag/Capping layer 20~40nm WO3 as capping layer has been investigated and WO3 was demonstrated to be an effective capping layer and improve the luminance by a factor of 1.7 between the maximum and minimum transmittance of top contact. In this paper, the thicknesses of organic layers are calculated based on Fabry-Perot cavity theory. And with optimized, the top -emitting organic devices with single-mode resonance have a good ability such as a brightness of 40920cd/m2 at the current density of 600ma/cm2 and a maximum luminous efficiency of 7.32cd/A at 9145cd/m2.