基于玻璃基波导的石墨烯光电探测器的研究

发布时间：2018-08-07 13:01

【摘要】：在集成光电子学的领域中,通过离子交换技术制作的玻璃基光波导具有成本低廉、波长不敏感、环境稳定性好、易于在系统中集成等优势,适合于大批量生产光无源及有源器件。石墨烯作为一种新兴的二维材料,具有优异的光电特性,在理论和光电器件方面的研究也已取得了丰硕的成果。本文的研究工作主要集中于将玻璃基波导结构与石墨烯相结合,利用石墨烯独特的光电特性,设计并成功制作了基于玻璃基波导的石墨烯光电探测器。该器件的工作原理基于光电导效应,当石墨烯吸收波导中光子的能量后,价带的电子被激励到导带上,产生光生载流子,从而使石墨烯的电阻减小,器件的光电流增大。不同功率的光入射到器件上会产生大小不同的光电流,从而实现光电探测。本文的主要内容如下:本文从玻璃基热离子交换以及石墨烯的经典理论出发,计算了 Ag+-Na+离子交换的归一化离子浓度、扩散深度、石墨烯的电导率、介电常数以及载流子浓度等基本物理参数。在此基础上建立了一个金属-石墨烯-金属光电探测器的模型并计算了光电流的值,从理论上分析了基于玻璃波导的石墨烯光探测器的性能。本文设计了两种不同电极结构的光电探测器,通过实验对工艺流程进行了探索并详细阐明了实验条件下合理的工艺过程参数,为光电探测器的成功制作奠定了基础并为其他基于玻璃波导的石墨烯光器件的制作提供了相关依据。本文对两种不同电极结构的光电探测器分别进行了测试。结果表明,在外加偏置电压为1V的条件下,当入射光的波长在1500-1600nm范围内探测器响应度具有良好的稳定性和一致性。对于1550nm波长入射光,平行电极器件的最大响应度可以达到0.21A/W,叉指电极器件的最大响应度达到0.28A/W。最后,从电导率、电场强度、迁移率等方面对测试结果进行了分析,并与理论仿真对比,探讨了理论计算与实验结果之间的异同及原因。
[Abstract]:In the field of integrated optoelectronics, the glass-based optical waveguide fabricated by ion exchange technology has the advantages of low cost, insensitive wavelength, good environmental stability and easy integration in the system. Suitable for mass production of optical passive and active devices. As a new two-dimensional material, graphene has excellent photoelectric properties, and has made great achievements in theory and optoelectronic devices. In this paper, we mainly focus on the combination of glass-based waveguide structure and graphene. Based on the unique photoelectric characteristics of graphene, a graphene photodetector based on glass-based waveguide is designed and fabricated successfully. The principle of the device is based on the photoconductivity effect. When graphene absorbs the energy of photons in the waveguide, the valence band electrons are excited to the conduction band, resulting in photogenerated carriers, thus reducing the resistance of graphene and increasing the photocurrent of the device. Different power of light incident on the device will produce different photocurrent, so as to achieve photoelectric detection. The main contents of this paper are as follows: based on the classical theory of glass based thermal ion exchange and graphene, the normalized ion concentration, diffusion depth, conductivity of graphene are calculated. Basic physical parameters such as dielectric constant and carrier concentration. On this basis, a model of metal-graphene metal photodetector is established and the photocurrent value is calculated. The performance of graphene photodetector based on glass waveguide is analyzed theoretically. In this paper, two kinds of photodetectors with different electrode structures are designed. The process flow is explored by experiments and the reasonable process parameters under the experimental conditions are expounded in detail. It lays a foundation for the successful fabrication of photodetectors and provides the relevant basis for the fabrication of other graphene optical devices based on glass waveguide. In this paper, two kinds of photodetectors with different electrode structures have been tested. The results show that the detector responsivity is stable and consistent when the wavelength of the incident light is in the range of 1500-1600nm under the applied bias voltage of 1V. For 1550nm wavelength incident light, the maximum responsivity of parallel electrode devices can reach 0.21A / W, and the maximum responsivity of interDigital electrode devices can reach 0.28A / W. Finally, the test results are analyzed from the aspects of conductivity, electric field intensity and mobility, and compared with the theoretical simulation, the similarities and differences between the theoretical calculation and the experimental results and the reasons are discussed.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN15

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