摘要
目的通过设计一种新型p-GaN/ZnO(薄膜+纳米线)三明治异质结结构,提高ZnO对紫外光的响应。方法利用化学气相沉积(CVD)方法,在蓝宝石/GaN衬底上生长出纳米线+薄膜交错排列的ZnO,得到具有三明治结构的p-GaN/ZnO材料。通过旋涂Ag纳米线(NWS)、滴银胶为电极,制备三明治结构的异质结紫外(UV)光电探测器。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)表征物相及形貌;利用光致发光(PL)和拉曼(Raman)光谱分析晶体结晶情况;利用半导体分析测试仪对该三明治异质结UV光电探测器进行光电性能测试,得到其光电性能变化规律。结果该三明治结构光电探测器顶部为ZnO薄膜,中间为ZnONWS与纳米片交错排列分布,底部为GaN。这种二维(2D)/一维(1D)/2D结构使入射光在结构内多次反射和散射,提高了光程长度,进而提高了光吸收。另外,由于p-GaN和n-ZnO形成PN结,在内建电场作用下,可以有效提高光生电子-空穴分离效率。光电性能测试结果表明,在偏压2V、光功率密度520μW/cm^(2)(365nm)条件下,响应度(R)为35.8A/W,上升时间(t_(r))为41.83ms,下降时间(t_(d))为43.21ms,外量子效率(E_(q))为122%,比探测率(D^(*))为1.31×10^(12)cm·Hz^(1/2)·W^(-1)。结论通过一步CVD法制备新型p-GaN/ZnO纳米线/ZnO薄膜三明治结构UV光电探测器,可以有效提高ZnO对紫外光的响应,为探索新式结构光电探测器提供可能。
The photodetector is a device that converts an optical signal into an electrical one.In our daily life,high-performance photodetectors play an important role in many fields,including photoelectric display,imaging,environmental monitoring,optical communication,military,security inspection,and etc.It is a critical component in the modern miniaturized electronic industry.The work aims to design a novel p-GaN/ZnO(thin film+nanowire)sandwich heterojunction structure to improve the response of ZnO to ultraviolet light.The sandwich structure of ZnO nanowire(NWS)and nanosheet was grown by chemical vapor deposition(CVD)in a single-temperature zone high-temperature tubular furnace,and its growth temperature was 1050℃,holding time was 25 min,and with 30 mL/min argon protection.First of all,spin Ag NWS on the surface of ZnO thin film with the spin-coating method uniformly.Secondly,dilute hydrochloric acid was used to erase the ZnO structure on the GaN substrate as the attachment point of the silver glue.At the same time,a drop of silver gel on the Ag NWS was used as another attachment point,then the process of UV photodetector based on p-GaN/ZnO heterojunction was completed.The advantage of the electrode preparation process of this device was that it could avoid tedious steps such as light carvings.X-ray diffractometer(XRD)and scanning electron microscope(SEM)were used to characterize the phase and morphology and the law of photoelectric performance.The changes of sandwich heterojunction UV photodetector were tested with a semiconductor analyzer.The results indicated that the sandwich structure sample was interlaced with ZnO NWS and ZnO nanosheets inside,and its surface was ZnO thin film and relatively smooth.ZnO was single crystal with good crystal quality.The photodetector had obvious rectifier characteristics,at 2 V bias voltage,520μW/cm^(2) optical power density(365 nm),the responsivity(R)was 35.8 A/W,the rise time(tr)was 41.83 ms,the descending time(td)was 43.21 ms,the external quantum efficiency(Eq)was 122%,and the
作者
李刚
付政伟
宋艳东
马宗义
刘子童
冯礼志
冯思雨
LI Gang;FU Zheng-wei;SONG Yan-dong;MA Zong-yi;LIU Zi-tong;FENG Li-zhi;FENG Si-yu(School of Materials Science and Engineering,Liaoning Technical University,Liaoning Fuxin 123000,China;School of Materials Science and Engineering,Yingkou Institute of Technology,Liaoning Yingkou 115000,China;Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110000,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2023年第6期384-391,共8页
Surface Technology
基金
辽宁省教育厅科技研究项目(LJKZ1195)
营口理工学院创新团队支持计划(TD202001)
营口理工学院高层次人才科研启动项目(YJRC202014)。
关键词
异质结
光电探测器
CVD
响应度
比探测率
外量子效率
heterojunction
photodetector
CVD
responsivity
specific detectivity
external quantum efficiency
