量子点发光二极管功能层厚度确定方法  

Thickness Estimation Method for Every Functional Layer of QLEDs

作　　者：陈雯柏[1] 叶继兴 马航[1] 李邓化[1,2] 

机构地区：[1]北京信息科技大学自动化学院,北京100101 [2]北京交通大学电子信息工程学院,北京100044

出　　处：《光子学报》2017年第8期8-14,共7页Acta Photonica Sinica

基　　金：国家重点基础研究发展计划(No.2015CB654605)资助~~

摘　　要：为改善量子点发光二极管器件载流子注入平衡,提出一种量子点发光二极管各功能层厚度的确定方法.首先选定量子点发光层厚度,基于隧穿模型进行仿真分析确定电子传输层厚度;然后采用空间电荷限制电流模型进行仿真分析确定空穴传输层厚度.采用CdSe/ZnS量子点作为发光层、poly-TPD作为空穴传输层、Alq_3作为电子传输层,按照该方法仿真分析得到各功能层厚度进行旋涂-蒸镀法实物器件制备.对比实验结果表明:当poly-TPD、QDs及Alq_3厚度分别为45nm、25nm及35nm时,获得了较高的发光效率及色纯度,器件性能最好.该方法确定的各功能层厚度有助于减少载流子在发光界面积累,获得载流子的注入平衡,从而改善QLEDs发光性能.To balance the carrier injection in Quantum Dot Light Emitting Diode（QLEDs）,a method to determine the thickness of each functional layer was proposed.The thickness of EL was set firstly,the thickness of Electron Transport Layer（ETL）was determined through tunneling model.On this basis,the thickness of Hole Injection Layer（HTL）was determined at last using space charge limited current model.Devices using red light CdSe/ZnS quantum dot was used as the Light-Emitting Layer（EL）,poly-TPD as the HTL,Alq3 as the ETL were fabricated through spin-coating and vacuum evaporation with the thickness of each layer obtained from the simulation results.Experiment results show that compared with other devices,the device with a 45 nm thickness of poly-TPD,25 nm QDs and 35 nm Alq3 has a higher luminous efficiency and color purity.QLEDs with the thickness of each layer chosen according to the method proposed have a more balanced carrier injection which is advantageous in improving device performance.

关 键 词：量子点发光二极管 载流子注入平衡 空穴传输层 发光层 电子传输层 隧穿模型 空间电荷限制电流模型 

分 类 号：O472.3[理学—半导体物理]