ZnO/C8-BTBT异质结的载流子注入特性研究

Carrier Injection Characteristics of ZnO/C8-BTBT Heterojunction

量子点电致发光器件(QLED)中的发光层由钙钛矿量子点构成。由于量子点较深的价带能级,空穴载流子注入效率相对较低,往往成为制约器件性能的重要因素。采用p-型有机半导体,2,7-二辛基[1]苯并噻吩并[3,2-b]苯并噻吩(C8-BTBT)作为发光层主体材料,与量子点构成的主客体复合薄膜,被证明是一种有效的解决方法,而研究和调控载流子向这类有机主体材料的注入特性是提高这类QLED器件性能的关键。采用场效应薄膜晶体管和单载流子叠层器件结构表征了ZnO/C8-BTBT异质结的载流子传输特性。实验发现通过引入ZnO/C8-BTBT异质结,一方面可提高器件的空穴注入效率,另一方面有利于实现更平衡的载流子注入特性。

The luminescent layer in a quantum dot electroluminescent device(QLED)is consisted of perovskite quantum dots.The reason of low injection efficiency of hole carrier is that the quantum dot usually has a deep-lying valence energy levels.It is an important factor that limited device performance.Adopting the host-guest composite film which consisted of quantum dot and the p-type organic semiconductor 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene(C8-BTBT)as a light-emitting layer was an effective way.Therefore,study and control the injection characteristics of carriers into this kind of organic host materials was important to improve the performance of such QLED devices.The field effect thin film transistor and single carrier stacked device structure was used to characterize the carrier transport characteristics of ZnO/C8-BTBT heterojunction.It is found that the introduction of ZnO/C8-BTBT heterojunction can improve the hole injection efficiency of the device,and on the other hand,it can achieve more balanced carrier injection characteristics.