ZnO 박막 전자수송층의 공기 노출에 의한 양자점 발광다이오드의 특성 변화

Abstract

We investigated the electrical characteristics of ZnO nanoparticles (NPs) with air exposure that is a widely used electrontransport layer for quantum dot light-emitting diodes (QLEDs). Upon air exposure, we observed changes in the densityof states (DOS) of the trap levels of ZnO NPs. In particular, with air exposure, the concentration of deep trap energylevels in ZnO NPs decreased and electron mobility significantly improved. Consequently, the air-exposed ZnO reducedleakage current by approximately one order of magnitude and enhanced the external quantum efficiency at the low drivingvoltage region of the QLED. In addition, based on the excellent conductivity properties, high-brightness QLEDs couldbe achieved.