Deep localization features of photoluminescence in narrow AlGaN quantum wells

作     者：DENG Jianyang LI Rui GUO Yanan WANG Junxi WANG Chengxin JI Ziwu 

作者机构：School of Integrated Circuits， Institute of Novel Semiconductors， Shandong University Research and Development Center for Solid State Lighting， Institute of Semiconductors， Chinese Academy of Sciences Shandong Inspur Huaguang Optoelectronics Co.， Ltd. 

出 版 物：《Optoelectronics Letters》 (光电子快报(英文))

年 卷 期：2024年

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

摘      要：The research prepared two deep ultraviolet (DUV) AlGaN-based multiple quantum well (MQW) samples having same Al content in the QWs but different well widths (3 nm for Sample A and 2 nm for Sample B). Photoluminescence (PL) measurements reveal that， Sample A exhibits only one main PL peak across all measured temperatures， in contrast， Sample B displays one main PL peak at low temperatures and two distinct PL peaks at high temperatures. Furthermore， compared with Sample A， Sample B exhibits a more significant temperature-dependent PL peak wavelength blueshift relative to the Varshni curve， a more significant excitation power density-dependent PL peak blueshift accompanied by linewidth broadening， as well as a larger non-radiative recombination related activation energy and higher internal quantum efficiency (IQE). These findings can be explained by the observation that the narrower well width of Sample B induces a more pronounced effect of carrier localization than the wider well width of Sample A， due to the enhanced fluctuation in well width and reduced quantum-confined Stark effect (QCSE).