Progress in Oxide-based Ultraviolet Detectors
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摘要: 随着紫外探测技术的不断发展,氧化物材料在紫外探测领域表现出传统探测器所不具备的优点而成为近年研究的热点,是继红外探测技术之后又一快速发展的军民两用探测技术。然而,氧化物基紫外光电探测器的广泛应用,仍然面临一些问题。本文对国内外紫外探测技术的应用和发展历史进行了概述,并对3种金属氧化物紫外探测材料的晶体结构、性质及其器件研究进展进行了概括和讨论。最后,针对氧化物基紫外探测材料及器件在研究中所面临的问题,进行了分析,并对氧化物基紫外探测技术的发展进行了总结与展望。Abstract: With the development of ultraviolet detection technology, oxide materials showing the unique advantages in the field of ultraviolet detection, which the traditional detectors didn't possess, and becoming a hot research topic in recent years. It is a fast-developing dual-purpose detection technology after the infrared detection technology. However, the wide applications of oxide-based ultraviolet detectors still face challenges. In this paper, we have summarized the applications and development histories of the ultraviolet detection technology at home and abroad. The crystal structures, properties and progresses in devices of three kinds of metal oxide ultraviolet materials are summarized and discussed. In the end, the problems in the research of the oxide-based ultraviolet detection materials and devices are analyzed, and the development of the oxide-based ultraviolet detection technology is summarized and prospected.
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Key words:
- photoelectric detection /
- oxide-based materials /
- ultraviolet detectors
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图 3 不同形貌的ZnO纳米结构:(a) ZnO纳米颗粒的透射电子显微镜(transmission electron microscope, TEM)图[28];(b) ZnO纳米线的场发射扫描电子显微镜(field emission scanning electron microscope, FE-SEM)图,插图为局部放大图[29];(c)单个ZnO纳米棒横截面的SEM图[30];(d) ZnO纳米管的SEM图,插图为高分辨SEM图[31];(e) ZnO纳米带的SEM图,插图是ZnO纳米带的TEM图[32];(f) ZnO纳米锯的SEM图,插图为放大的SEM图[33];(g) ZnO纳米螺旋的SEM图和TEM图[34];(h) ZnO纳米环的TEM图,插图是椭圆选区放大图[35]
Figure 3. ZnO nanostructures with different morphologies: (a) TEM image of ZnO nanoparticles[28]; (b) FE-SEM image of ZnO nanowires and the inset is a partial enlarged detail[29]; (c) SEM image of cross section of single ZnO nanorod[30]; (d) SEM image of ZnO nanotubes and the inset is a HR-SEM image[31]; (e) SEM image of ZnO nanobelts and the inset is a TEM image of a ZnO nanobelt[32]; (f) SEM image of ZnO nanosaws and the inset shows magnified SEM image[33]; (g) SEM and TEM images of ZnO nanohelix[34]; (h) TEM image of ZnO nanorings and the inset is a magnified image from the elliptical selection[35]
图 4 ZnO的结构图:(a) ZnO晶体结构;(b) ZnO晶体显微图;(c)和(d)在不同沉积时间下2D有序ZnO多孔薄膜的SEM图[38];(e)单壁ZnO纳米管的展开蜂巢晶格,插图是单层ZnO[39];(f) ZnO三维空间结构;(g)和(h) 3D阵列ZnO纳米棒的SEM图[40]
Figure 4. Structure diagrams of ZnO: (a) Crystal structure of ZnO; (b) Micrograph of ZnO crystal; (c)and(d) SEM images of the 2D ordered ZnO porous films with different deposition times: (c) 40 min and (d) 2 h[38]; (e) Unrolled honeycomb lattice of a single-walled ZnO NTs and the inset is single layer ZnO[39]; (f) 3D structure of ZnO; (g) and (h) SEM images of 3D array ZnO NRs[40]
图 5 β-Ga2O3的结构与性质:(a) β-Ga2O3晶体结构示意图[49];(b)和(c) (100)β-Ga2O3和[010]β-Ga2O3的原子排列模型[50];(d) 5种不同结构Ga2O3之间的转化关系及条件;(e) β-Ga2O3的TEM图和STEM HAADF图[50-51];(f)在黑暗和紫外光照射下基于β-Ga2O3的MSM光电探测器的能带示意图[52];(g) MBE生长的β-Ga2O3薄膜的XRD图谱和XRR图谱与拟合曲线(红色所示)[52]
Figure 5. Structure and properties of β-Ga2O3: (a) Schematic diagram of β-Ga2O3 crystal structure[49]; (b) and (c) Atomic arrangement models of (100)β-Ga2O3 and [010]β-Ga2O3[50]; (d) Conversion relationships and conditions among five different structures of Ga2O3; (e) SEM and STEM HAADF images of β-Ga2O3[50-51]; (f) Energy band diagrams of MSM photodetector based on β-Ga2O3 under dark and UV illumination[52]; (g) XRD pattern and XRR pattern with fitting curve(shown in red)of β-Ga2O3film grown by MBE[52]
图 6 TiO2的结构与性质:(a)锐钛矿TiO2和金红石TiO2的晶胞;(b)离轴磁控溅射示意图;(c)和(f)厚度为500nm的TiO2 TEM图和电子衍射图;(d)和(e)不同位置处沉积的TiO2薄膜的XRD图谱
Figure 6. Structure and properties of TiO2: (a) Unit cells of anatase TiO2 and rutile TiO2; (b) Schematic of off-axis magnetron sputtering; (c) and(f) TEM images and electron diffraction pattern of TiO2 films with a thickness of 500 nm; (d)and(e) XRD patterns of TiO2 films deposited at different positions
图 7 TiO2基MSM紫外探测器:(a),(b)和(c)金红石TiO2基MSM紫外光电探测器的器件结构及其叉指电极的光学显微图像和TiO2薄膜的TEM图[64];(d),(e),(f),(g)和(h)锐钛矿TiO2基MSM探测器的器件结构、TiO2 薄膜的AFM图像和SEM显微图像、I-V特性以及其能带示意图[65]
Figure 7. TiO2-based MSM ultraviolet detectors: (a), (b) and (c) Device structure of rutile-TiO2-based MSM ultraviolet photodetector, optical microscopic image of its inter digital electrodes, and TEM image of the TiO2 film[64]; (d), (e), (f), (g) and (h) Device structure of the anatase-TiO2-based MSM detector, AFM image and SEM micrograph of the TiO2 film, I-V characteristics curves, and energy band diagram of the detector[65]
表 1 金属氧化物紫外探测材料及器件性能
Table 1. Metal oxide ultraviolet detection materials and device performance
Materials Devices Preparation method Form Wavelength range/nm Structure Max responsivity/
(AW-1)EQE/
(%)Dark current or
Il/Id radioRef. ZnO RF magnetron sputtering Thin films 200-380 MSM 3.37×10-1 - 1 nA [11] Ga2O3 RF magnetron sputtering Thin films 254-365 MSM 8.926×10-1 444 1×10-11A [12] TiO2 Hydrothermal Nano-wires 290-400 Photocon-duction 1.021×103 3800 1.67×104 A [13] SnO2 High temperature carbon thermal
reductionNano-wires 200-400 MSM 104 300000 102 [14] In2O3 Electron beam evaporation Nano-rods 290-390 Schottky 1.5×101 - - [15] Sm2O3 RF magnetron sputtering Thin films 254-365 Hetero-structure - - 172 [16] CdO Chemical spray pyrolysis technique Nano-films 200-386 Photocon-duction - - 68 mA [17] -
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