一种表面等离子体增强的近红外光电探测器的设计与研究

发布时间：2018-04-18 14:54

本文选题：铜纳米颗粒阵列 + 表面等离子体共振　；参考：《合肥工业大学》2017年硕士论文

【摘要】：近些年来,贵金属(如金、银)纳米结构已经被广泛采用来增加各类光电器件的性能,如光伏器件,光电探测器,波导器件等。作为传统贵金属的可替代物,普通金属(如铜,铝等)由于具有相对低廉的制备成本及可协调的等离子体波长等优点,基于它们的表面等离子体光电器件也受到越来越多研究者的兴趣。大量的研究报道表明,等离子体纳米结构与半导体结合是改善各种光电器件性能的可靠途径。此外,高度局域的电磁场能产生大量的电子-空穴对,并能越过势垒从等离子体材料注入到半导体材料中,从而增强光电流。所以在本文中,我们提出了一种新的基于等离子铜纳米颗粒阵列修饰的石墨烯/硒化镉纳米带肖特基结近红外光电探测器。文中,我们通过有限元法对铜纳米颗粒阵列的光学特性进行了理论模拟,发现当铜纳米颗粒阵列的尺寸改变时,其等离子体特性也会呈现差异。并随着颗粒边长和厚度的变化,铜纳米颗粒阵列在700到900nm范围呈现很明显的局域表面等离子体共振效应。通过对修饰铜纳米颗粒阵列前后的石墨烯/硒化镉纳米带肖特基结近红外光电探测器的光电性能进行对比分析,我们发现修饰了铜纳米颗粒阵列后,器件的光电流从0.124增大到3.1mA,增强了将近24倍。此外,其他的器件参数(比如响应度、增益)也得到了相应的提高。结合有限元法的理论模拟,我们发现器件性能的优化主要得益于LSPR诱导的热电子注入效应。这些研究结果表明等离子体铜纳米颗粒阵列是提高纳米光电器件光电性能的非常有潜力的候选者。
[Abstract]:In recent years, noble metals (such as gold, silver) nanostructures have been widely used to increase the performance of various photovoltaic devices, such as photovoltaic devices, photodetectors, waveguide devices and so on.As a substitute for traditional precious metals, ordinary metals (such as copper, aluminum, etc.) have the advantages of relatively low preparation cost and compatible plasma wavelength.Surface plasma optoelectronic devices based on them have also attracted more and more researchers' interest.A large number of research reports show that the combination of plasma nanostructures and semiconductors is a reliable way to improve the performance of various optoelectronic devices.In addition, highly localized electromagnetic fields can produce a large number of electron-hole pairs and can be injected from plasma materials into semiconductor materials over potential barriers, thus enhancing photocurrent.In this paper, we propose a novel Schottky junction near infrared photodetector based on plasma copper nanoparticles array modified graphene / cadmium selenide nanoribbons.In this paper, we theoretically simulate the optical properties of copper nanoparticles array by finite element method. It is found that the plasma characteristics of copper nanocrystalline array are different when the size of the array changes.With the change of the side length and thickness of the particles, the local surface plasmon resonance (SPR) effect is obvious in the range of 700 to 900nm.By comparing and analyzing the photoelectric properties of graphene / cadmium selenide nanospheres Schottky junction near infrared photodetectors before and after modification of copper nanoparticles array, we found that after modification of copper nanoparticles array,The photocurrent of the device increased nearly 24 times from 0.124 to 3.1 Ma.In addition, other device parameters (such as responsivity, gain) are also improved.Combined with the theoretical simulation of finite element method, we find that the optimization of device performance is mainly due to the hot electron injection effect induced by LSPR.These results indicate that the plasma copper nanoparticles array is a promising candidate for improving the optoelectronic performance of nano-optoelectronic devices.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN215

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