基于锑化镓和硫化锑纳米线光探测器件的光电特性研究

发布时间：2018-05-14 12:14

本文选题：锑化镓纳米线 + 硫化锑纳米线　；参考：《华中科技大学》2015年硕士论文

【摘要】：锑化镓作为重要的III-V族半导体材料,拥有高的空穴迁移率850 cm2/Vs和合适的带隙(0.7 eV)被用来制作光探测器件,尤其是高速响应的红外光探测器件。锑化镓属于低阻抗高迁移率材料,用锑化镓纳米线作光探测器材料,其灵敏度和探测率等性能相对较高,适合探测光强较小的可见光和近红外光。同样是锑属化合物的硫化锑纳米线也是很好的光电子材料,拥有带隙(1.5~2.2 eV)能探测近紫外到近红外的光,可以作为宽光谱探测应用。硫化锑属于高阻抗材料低迁移率材料,用硫化锑纳米线作光探测器材料,其光开关稳定性能相对较好,适合探测不同光强的紫外光至近红外光范围。但器件的响应度和灵敏度等性能不如锑化镓,因此通过改进器件的结构,可以使得性能得到提升。本论文的主要内容包括如下两方面:1.采用化学气相沉积法在硅基底上生长锑化镓纳米线,并在硅/二氧化硅基底上制备基于单根锑化镓纳米线的光探测器件。通过性能测试发现,制作好的器件展现出极高的灵敏度,快速的响应速度以及稳定的开关特性。在波长700 nm、光强度0.2 mW/cm2的光照下,显示出光响应度为295 A/W,响应时间为80 ms。而基于柔性基底上的光探测器,显示出可比拟硅/二氧化硅基底上的性能并且拥有更低的暗电流。同样条件下的光照时,柔性探测器的探测率达到9.7×109琼斯,等效噪声功率达到2.0×10-12W/Hz1/2。2.同样使用简单的化学气相沉积法制备出单晶结构高质量的硫化锑纳米线,并对硫化锑纳米线进行金纳米颗粒的修饰,同时制作出基于硅/二氧化硅基底上的金纳米颗粒修饰的硫化锑纳米线光探测器件和未修饰的器件。通过对两种器件的性能比较发现,经过金纳米颗粒修饰后,光电流得到明显提高,响应时间减少,并且对现象的成因进行了研究解释。而对柔性基底上的光探测器件研究显示,修饰同样使得器件的性能增加,白光响应度从4.9 A/W提高到20A/W。
[Abstract]:As an important III-V semiconductor material, gallium antimonide has a high hole mobility of 850 cm2/Vs and a suitable bandgap of 0.7 EV), which is used to fabricate photodetectors, especially those with high response to high speed. Gallium antimonide is a kind of low impedance and high mobility material. The sensitivity and detectivity of GaSb nanowires are relatively high, so it is suitable for detecting visible and near infrared light with low light intensity. Antimony sulfide nanowires, which are also antimony compounds, are also very good optoelectronic materials with band gap 1.52.2eV) which can detect near ultraviolet to near infrared light and can be used as wide spectrum detection applications. Antimony sulfide is a kind of high impedance material and low mobility material. Using antimony sulfide nanowires as photodetector material, the stability of optical switch is relatively good, which is suitable for detecting the range of ultraviolet to near infrared light with different light intensities. However, the responsivity and sensitivity of the device are not as good as that of gallium antimonide, so the performance can be improved by improving the structure of the device. The main contents of this thesis include the following two aspects: 1. Gallium antimonide nanowires were grown on silicon substrate by chemical vapor deposition and photodetectors based on single gan nanowires were prepared on silicon / silica substrates. The performance tests show that the fabricated devices exhibit very high sensitivity, fast response speed and stable switching characteristics. When the wavelength is 700nm and the light intensity is 0.2 mW/cm2, the light responsivity is 295 A / W and the response time is 80 Ms. Photodetectors based on flexible substrates show comparable performance on silicon / silica substrates and have lower dark currents. Under the same illumination conditions, the detectivity of the flexible detector is 9.7 脳 109 Jones, and the equivalent noise power is 2.0 脳 10 ~ (-12) W / Hz / 2.2. The high quality antimony sulfide nanowires with single crystal structure were also prepared by simple chemical vapor deposition method, and the antimony sulfide nanowires were modified with gold nanoparticles. At the same time, the antimony sulfide nanowire photodetectors and unmodified devices were fabricated based on gold nanoparticles on silicon / silica substrate. By comparing the performance of the two devices, it is found that the photocurrent is obviously improved and the response time is reduced after the gold nanoparticles are modified. The causes of the phenomenon are also studied and explained. The study of photodetectors on the flexible substrate shows that the modification also increases the performance of the device, and the white light responsivity increases from 4.9 A / W to 20 A / W.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN36

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