本征富受主型ZnO微米管光致发光的温度调控机制  

Thermal regulation mechanism of photoluminescence in intrinsic acceptor-rich ZnO microtube

作　　者：王强 杨立学 刘北云 闫胤洲[2] 陈飞 蒋毅坚 Wang Qiang;Yang Li-Xue;Liu Bei-Yun;Yan Yin-Zhou;Chen Fei;Jiang Yi-Jian(Department of Materials Science and Engineering,Beijing Institute of Petrochemical Technology,Beijing 102617,China;Institute of Laser Engineering,Beijing University of Technology,Beijing 100124,China;School of Science,Guangxi University of Science and Technology,Liuzhou 545006,China)

机构地区：[1]北京石油化工学院,材料科学与工程学院,北京102617 [2]北京工业大学,激光工程研究院,北京100124 [3]广西科技大学理学院,柳州545006

出　　处：《物理学报》2020年第19期275-281,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11674018);北京市科技新星计划(批准号:Z171100001117101);北京石油化工学院科技创新资助项目(批准号:15031862005/298)资助的课题.

摘　　要：热效应是影响半导体器件发光性能的最关键因素之一.本文针对光学气化过饱和析出法制备的本征富受主型ZnO微米管,系统研究了其光致发光的温度调控机制.研究表明,所制备ZnO微米管具有规则的六边形截面形貌,长度达5 mm、直径达100μm,室温下的光学带隙约为3.30 eV;随着环境温度的提高,其光致发光强度呈现“热淬灭-负热淬灭-热淬灭”的反常变化.在80—200 K温区内的热淬灭行为与浅施主的退/电离、自由激子热离化以及中性受主束缚激子的转变有关;在200—240 K温区内发生的负热淬灭行为与导带底以下488 meV处深能级陷阱上电子的热激发有关;在240—470 K温区内发生的热淬灭行为则与导带底以下628 meV处非辐射复合中心的Shockley Read-Hall复合有关.非辐射复合中心和陷阱中心的形成均与本征富受主型ZnO微米管的氧空位缺陷有关.上述研究结果在高温高效富受主型ZnO微米管基光电器件的设计与研发方面具有重要指导意义.Thermal effect is one of the most important factors limiting the photoluminescence performances of semiconductor devices.With the increase of temperature,the PL intensity decreases gradually due to the effect of thermal quenching.However,the abnormal negative thermal quenching effect has been found in many semiconductor materials in recent years,e.g.ZnO,BiFeO3,InPBi,etc.This effect is generally considered as the sign of the existence for middle/local energy state in the electron-hole recombination process,which usually needs to be confirmed by the temperature-dependent PL spectra.Here,we report the thermal regulation mechanism of photoluminescence in intrinsic acceptor-rich ZnO(AZnO)microtubes grown by the optical vapour supersaturated precipitation method.The grown A-ZnO microtube with a length of 5 mm and diameter of 100μm has regular hexagonal cross-section morphology.Its optical band gap at room temperature is about 3.30 eV.With the increase of temperature,the PL intensity of A-ZnO microtube exhibits an abnormal behavior from the thermal quenching to the negative thermal quenching and then to the thermal quenching.The thermal quenching effect at 80–200 K is associated with regurgitation/ionization of shallow donor,thermal ionization of free exciton,and conversion of neutral acceptor bound exciton.The negative thermal quenching effect at 200–240 K is associated with thermal excitation of electrons in a deep level trap of 488 meV below the conduction band minimum(CBM).The thermal quenching effect at 240–470 K is related to Shockley-Read-Hall recombination based on the non-radiative recombination center of 628 meV below the CBM.The non-radiative recombination center and trap level are far from the acceptor level of A-ZnO microtube,which may be related to the deep-level defect of oxygen vacancy in the intrinsic A-ZnO microtube.This work establishes the temperature-dependent transition model of photo-generated carriers and reveals the thermal regulation mechanism of PL for the A-ZnO microtubes.It provides a

关 键 词：氧化锌 光致发光 热淬灭 负热淬灭 

分 类 号：TN303[电子电信—物理电子学]