Investigation of operation and degradation mechanisms in ZnTeSe blue quantum-dot light-emitting diodes by identifying recombination zone  

作　　者：Oul Cho Sujin Park Hogeun Chang Jiwhan Kim Jaekwon Kim Sungwoo Kim Taehyung Kim Jeonghun Kwak 

机构地区：[1]Department of Electrical and Computer Engineering,Inter-university Semiconductor Research Center,and Soft Foundry Institute,Seoul National University,Seoul 08826,Republic of Korea [2]Material Research Center,Samsung Advanced Institute of Technology,Suwon,Gyeonggi-do 16419,Republic of Korea

出　　处：《Nano Research》2024年第7期6527-6533,共7页纳米研究（英文版）

摘　　要：ZnTeSe quantum dots(QDs),recognized as promising eco-friendly blue electroluminescent emitters,remain under-explored in light-emitting diode(LED)applications.Here,to elucidate the operation and degradation mechanisms of ZnTeSe blue QD-LEDs,stacked ZnTeSe QD layers with discernable luminescence are designed by varying Te doping concentrations,and the recombination zones(RZs)of the blue QD-LEDs are investigated.The RZs are identified near the hole-transport layer(HTL),confirmed by angular-dependent electroluminescence measurements and optical simulations.In addition,in order to investigate carrier dynamics in the process of recombination,the transient electroluminescence(tr-EL)signals of the dichromatic QD-LEDs are analyzed.As a result,it is inferred that the RZ initially formed near the electron-transport layer(ETL)due to the high injection barriers of electrons.However,due to the fast electron mobility,the RZ shifts toward the HTL as the operating current increases.After the device lifetime tests,the RZ remains stationary while the photoluminescence(PL)corresponding to the RZ undergoes a substantial decrease,indicating that the degradation is accelerated by the concentrated RZ.Thus this study contributes to a deeper understanding of the operational mechanisms of ZnTeSe blue QD-LEDs.

关 键 词：quantum dots light-emitting diodes DEGRADATION recombination zones carrier dynamics 

分 类 号：TN312.8[电子电信—物理电子学]