High efficiency phosphorescent organic light emitting diodes using triplet quantum well structure

Abstract

Light emission in phosphorescent quantum well structure which can confine excitons within an emitting layer was investigated. A multilayer quantum well structure which has a narrow triplet band gap host material sandwiched between wide triplet band gap host materials was designed, and device performances were studied. The multilayer emitting structure gave high efficiency of 47 cdA compared with 11 cdA of standard green devices. © 2007 American Institute of Physics.