一维纳米氧化锌自驱动紫外探测器的构建与性能研究  

Frabrication and properties of self-powered ultraviolet detectors based on one-demensional ZnO nanomaterials

作　　者：齐俊杰[1] 徐旻轩 胡小峰[1] 张跃[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《物理学报》2015年第17期66-71,共6页Acta Physica Sinica

基　　金：重大科学研究计划(批准号:2013CB932601);国际科技合作专项项目(批准号:2012DFA50990);国家自然科学基金(批准号:51232001;51172022);北京市教委共建项目;长江团队项目资助的课题~~

摘　　要：本文通过化学气相沉积法制备了ZnO纳米材料,利用扫描电镜、光致发光谱、X衍射光谱及拉曼光谱等方法对制备的材料进行了表征.基于制备的单根ZnO线分别构建了三种不同结构的紫外探测器件:Ag-ZnO-Ag肖特基型、PEDOT:PSS/n-ZnO结型和p-Si/n-ZnO结型紫外探测器,并对器件的性能进行了研究.结果表明:三种不同结构的器件都表现出良好的整流特性,对紫外线均有明显的光响应;在零偏压下,都有明显的自驱动特性.三种器件中,p-Si/n-ZnO型紫外探测器性能最为优异:在零偏压下,暗电流约在1.2×10^(-3)nA,光电流在5.4 nA左右,光暗电流比为4.5×10~3,上升和下降时间分别为0.7 s和1 s.通过三类器件性能比较,表明无机p-Si更适合与ZnO构建pn结型自驱动紫外探测器.ZnO micro/nanowires were synthesized by chemical vapor deposition method. The morphology and structure of the products have been characterized by using scanning electron microscopy （SEM）, X-ray diffraction （XRD）, photolumi-nescence （PL） and micro-Raman scattering spectrometer, etc. Results show that the surface of the highly uniform ZnO wire is smooth and the as-synthesized ZnO wires show high crystal quality. Three types of UV detector are constructed using a single ZnO nanowire with different contact characteristics, and their corresponding performances are investigated systematically by using Keithley 4200-SCS and other equipments. All of the three different devices exhibit good rectifying characters and significant responsivity to ultraviolet light. The devices show self-driven features at zero bias. Compared with the devices made from Schottky contact and ZnO/PEDOT：PSS film, the present single ZnO nanowire/p-Si film devices with heterojunctions have the best self-powered function, which can be attributed to the stronger built-in electric field as well as the smaller dark current due to the insulating layer on the p-Si film. At zero bias, the fabricated ZnO nanowire/p-Si film device can deliver a dark current of 1.2 × 10^-3 nA and a high photosensitivity of about 4.5 × 10^3 under UV illumination. The response of the devices made from ZnO nanowire/p-Si film to UV illumination in air is pretty fast with the rise time of about 0.7 s and the fall time of about 1 s, which could be attributed to the fact that the photo-generated electron-hole pairs in the depletion layer is quickly separated by the built-in electric field, leading to a rapid response speed and a larger photocurrent. Comparison among the three kinds of devices indicates that the devices made from ZnO nanowire/p-Si film are the best candidate for UV detectors.

关 键 词：ZNO 肖特基 PN结 紫外探测器 

分 类 号：TN23[电子电信—物理电子学]