双空穴注入层对有机电致蓝光器件性能的改善  

Enhanced performance of blue organic light-emitting diodes by using a double hole injection layer

作　　者：刘亚东[1] 郭旺军[1] 张杰[1] 伍致生[1] 宋新潮[1] LIU Ya-dong;GUO Wang-jun;ZHANG Jie;WU Zhi-sheng;SONG Xin-chao(Xi′an Modern Chemistry Research Insititue,Xi'an,Shaanxi 710065,China)

机构地区：[1]西安近代化学研究所,陕西西安710065

出　　处：《光电子．激光》2020年第9期897-901,共5页Journal of Optoelectronics·Laser

基　　金：所青年科技创新基金(2017ZDXM-GY-046);陕西省科技厅项目(2017GY-105,2020GY-083);国家自然科学基金(21702159)。

摘　　要：CuI/CuPc被采用作为有机电致蓝光CBP:BCzVBi器件的双空穴注入层。采用双空穴注入层后使得CBP:BCzVBi蓝光器件的启亮电压降低至3.4 V,较采用CuPc单空穴注入层的CBP:BCzVBi蓝光器件低0.4 V。在驱动电流20 mA/cm^2的情况下,与单空穴注入层器件相比,采用该双空穴注入层结构使得器件电流效率提升约19%,亮度增加约17%,驱动电压降低0.9 V。采用Fowler-Nordheim(F-N)隧穿注入理论对器件空穴注入电流的影响因素进行了分析,发现双空穴注入层形成的能级台阶可以有效地改善发光器件的空穴注入效率,进而起到改善器件发光电流效率和降低驱动电压的目的。Lowering down the driven voltage can benefits to the luminous efficiency and the lifetime of the organic light-emitting device(OLED).To further decrease the hole injection barrier from the ITO anode surface to the hole transport layer is a effective way to lower down the driven voltage.In our work,a double hole injection layer(D-HIL)consisting of CuI/CuPc was adopted into a CBP:BCzVBi blue emitter device to increase the hole injection efficiency.Comparing with the reference device with the single HIL layer of CuPc,the turn-on voltage of 3.4 V was obtained in the D-HIL which lower 0.4 V than the reference device,and the Current Efficiency(CE)was improved 19%at 20 mA/cm2 along with the driven-voltage lower down 0.9 V than the reference device.The Fowler-Nordheim(F-N)tunneling theory was adopted to analyze the impact of hole injection barrier on the hole injection electricity current density,it can be found that the hole injection electricity current density for the D-HIL device was improved via a stepped energy level which means a more facilitated hole injection efficiency,and hence the driven electricity current along with the CE were improved.As a result,a clearly improvement in the CE and driven-voltage had been obtained in the D-HIL.

关 键 词：光电子学 有机电致发光二极管 蓝光器件 双空穴注入层 启亮电压 

分 类 号：O471.5[理学—半导体物理]