纤锌矿结构砷化镓纳米线中的深能级缺陷研究  

Investigation of deep‑level defects in wurtzite GaAs nanowire

作　　者：乔旭冕 李新化 谷毛毛 龚书磊 弓紫燕 吴超可 吴超 赵雷鸣 QIAO Xumian;LI Xinhua;GU Maomao;GONG Shulei;GONG Ziyan;WU Chaoke;WU Chao;ZHAO Leiming(Key Laboratory of Advanced Electronic Materials and Devices,Anhui Jianzhu University,Hefei 230601,China)

机构地区：[1]安徽建筑大学先进电子材料与器件重点实验室,安徽合肥230601

出　　处：《量子电子学报》2024年第4期671-678,共8页Chinese Journal of Quantum Electronics

基　　金：安徽省首批揭榜性质课题(2021e03020007);安徽省重点研究与开发计划项目(202104a05020048)。

摘　　要：深能级缺陷是造成纤锌矿结构砷化镓纳米线中持续光电导效应的主要原因。采用基于高斯分布的缺陷复合动力学方程分析了纤锌矿结构砷化镓纳米线的光电导衰减曲线,得到平均载流子捕获势垒为60.2 meV。通过分析光照下光电导瞬态行为,提出了基于缺陷光电离模型来提取特定缺陷能级水平特征的方法。通过拟合纤锌矿结构砷化镓纳米线的光离化谱,得到了0.69 eV的光电离能。光离化能和热捕获能之间的较大能量差异意味着缺陷与晶格有强耦合作用,这与闪锌矿结构砷化镓中EL2中心的行为相似。Deep-level defects are the main cause of persistent photoconductivity(PPC)effect in wurtzite gallium arsenide nanowires(WZ GaAs NWs).The photoconductivity attenuation curve of WZ GaAs NWs are analyzed using the Gauss distribution based defect composite dynamics equation,and an average carrier capture barrier of 60.2 meV is obtained.By analyzing the transient behavior of photoconductivity under illumination,a defect photoionization model is proposed to extract the characteristics of specific defect energy levels.Through fitting the photoionization spectrum of WZ GaAs NWs,a photoionization energy of 0.69 eV is obtained.The large energy difference between the photoionization energy and the thermal capture energy implies that there is a strong coupling between the defect and the lattice for WZ GaAs NWs,which is similar to the behavior of EL2 center in zinc-blende GaAs.

关 键 词：光电子学 光电导 纤锌矿结构砷化镓 深能级缺陷 分子束外延 

分 类 号：O436.4[机械工程—光学工程]