Study on Luminescence Properties of Blue phosphorescent Microcavity Organic Light-emitting Devices

摘要

A blue phosphorescent cavity organic light-emitting Devices (MOLED) is obtained. The structure is Glass/DBR/ITO/MoO_3(1nm)/TcTa(40nm)/CBP: FIRPIC(30nm, 6%)/TPBI(35nm)/LiF(1nm)/Al(80nm). For comparing, the OLED without cavity is also fabricated. The effect of microcavity structure on phosphorescent luminescent device is discussed. The result is shown that electroluminescence (EL) spectrum peak of OLED is on 470nm, the full width at half maximum (FWHM) is 60nm and the electroluminescence (EL) spectrum peak of MOLED is 470nm, the FWHM is 26 nm. That means that the latter is narrowed around the half compared with the former. The luminescence spectrum of OLED with microcavity structure can be narrowed, therefore color purity is improved. For MOLED, the maximum brightness and the maximum external quantum efficiency (EQE) is 9720 cd/m~2 and 16.4%, respectively. For OLED, the maximum brightness and external quantum efficiency is 9020 cd/m~2 and 14.2%, respectively. The experimental results show that the luminescence properties of microcavity devices have been improved greatly compared with the no cavity devices.