基于石墨烯与硅基纳米光波导复合结构的电光调制技术研究

发布时间：2018-01-11 11:18

  本文关键词：基于石墨烯与硅基纳米光波导复合结构的电光调制技术研究　出处：《中北大学》2016年博士论文　论文类型：学位论文

  更多相关文章： 纳米光波导 微环谐振腔 石墨烯 电光调制 类电磁诱导透明效应

【摘要】：随着现代数字化电子信息产业的发展,人们对电子储存器件的数据容量、电子信息处理器的运算速度提出的要求也越来越高。与电信号相比,光信号具有数据容量大、传输速度快、不受电磁场干扰等优点,因而要达到大数据量存储、高速处理和低功耗这些要求,急需通过光电芯片来打破微电子产业摩尔定律的限制。而硅基纳米光波导是构成光电芯片的基础单元,它可以在纳米尺度下完成光信号的传输与处理,是实现光子器件小型化、集成化必不可少的单元。石墨烯作为一种新兴的二维材料,其零带隙具有线性色散的能带结构、超高的载流子迁移速率以及电控可调的费米能级使石墨烯成为一种极具应用前景的光信号处理材料。然而,将石墨烯应用于高效的光电转换器件最大挑战之一就是单层石墨烯有限的光吸收率。而将石墨烯集成到光波导上通过石墨烯与波导表面倏逝波的相互作用则可以解决这一难题,不但可以增强光与石墨烯的相互作用,增大光电转换效率,而且可以控制波导中光的传输,这对光信息芯片中不可或缺的电光调制、光电探测等器件具有重大的研究意义与应用前景。本文以目前国际最新研究成果为指引,围绕石墨烯与纳米光波导器件的集成,开展了基于石墨烯的硅基纳米光波导电光调制特性的研究。对石墨烯-光波导复合材料的特性进行了分析研究,加工并制备出石墨烯-光波导光电集成结构,进行了实验测试与结果分析。首次实验制备出双层石墨烯电容结构与硅基微环谐振腔相结合的电光调制结构,首次提出利用渐变微环谐振腔增大调制效率,首次利用石墨烯调控级联光波导微环谐振腔中的类电磁诱导透明效应。相关研究内容可归结为以下几个方面:1、对光波导的传输模式和单模传输条件进行了理论分析;通过对负责光输入和输出的光波导纳米光栅各参数的仿真与优化,提高了光栅的耦合效率;对核心单元微环谐振腔进行了理论分析。最后利用L-Edit软件对微腔谐振器集成单元进行了优化设计。利用电子束曝光以及感应耦合等离子体刻蚀等工艺完成了垂直耦合光栅作为光信号输入输出端的条形光波导以及微环谐振腔,对微环谐振腔的传输特性进行了测试分析,得到了品质因子为105高Q值微环谐振腔。2、对石墨烯的结构性质进行了理论分析,理论仿真了石墨烯费米能级、介电常数、等参数随电压的变化关系。通过化学气相沉积的方法(CVD)在铜箔基底上生长了石墨烯薄膜,并通过湿法转移的方法转移到了硅光波导的表面。解决了石墨烯-纳米光波导集成芯片加工过程中的多个工艺难点,并通过电子束蒸发、ALD原子沉积、紫外光刻等实现了石墨烯薄膜的图形化以及电极的生长等工艺,最后与PCB板引线并键合,得到了石墨烯与纳米光波导结合的光电调制芯片。3、对微环谐振腔-石墨烯复合结构进行了电光调制测试,设计并加工了新型的渐变微环谐振腔-石墨烯复合结构来增强石墨烯与光的相互作用,以增大调制效率,测试得到了高达26dB的调制深度,对测试结果进行了详细分析。通过双环级联的纳米光波导微环谐振腔的参数进行计算优化,在芯片上观察到了类电磁诱导透明效应,并将石墨烯的电控光吸收原理应用到级联微环类电磁诱导透明效应中,并在实验中实现了石墨烯对光波导中类电磁诱导透明效应的调控,对谱线的蓝移和红移进行了详细的分析计算。
[Abstract]:With the development of modern digital electronic information industry, the people to the electronic data storage device capacity, electronic information processing speed requirements also increasingly high. Compared with electrical signals, optical signals with large data capacity, fast transmission speed, without electromagnetic interference and other advantages, and to achieve a large amount of data storage. High speed and low power consumption of these requirements, need to break through the photoelectric chip microelectronics industry Moore's law restrictions. While silicon nanometer waveguide is the basic unit of photoelectric chip, it can complete the transmission and processing of optical signals in the nanometer scale, is to realize the miniaturization of integrated photonic devices, essential graphite unit. Graphene as a new two-dimensional material, the zero band gap band structure with linear dispersion, the Fermi energy and electric charge carrier mobility high tunable graphene into For optical signal processing is a very promising material. However, graphene used in photoelectric converter, one of the biggest challenges is graphene limited light absorption rate. The graphene is integrated into the optical waveguide by means of interaction between graphene and the surface of the waveguide evanescent wave can solve this problem that can not only enhance the interaction between light and graphene, increasing photoelectric conversion efficiency, and can control the transmission of light in the waveguide, the electro-optic modulation an optical information chip, photoelectric detection device has the research significance and important application prospect. Based on the current research results of the latest international guidelines, focus on integration graphene and nano optical waveguide devices, to carry out the research of graphene based nano silicon optical waveguide electro-optic modulator based on the characteristics of graphene. Characteristics of optical waveguide composites is analyzed. Study on processing and preparation of graphene optoelectronic integrated optical waveguide structure, were tested with the experimental results. Analysis of structure of electro-optic modulation experiment for the first time prepared bilayer graphene structure and capacitance silicon micro ring resonator with micro ring resonator is proposed for the first time, increase the modulation efficiency using gradient, the first use of graphene the regulation of cascaded optical waveguide micro ring resonator in electromagnetically induced transparency like effect. The related research contents can be summarized as follows: 1, the optical waveguide transmission mode and single-mode transmission condition are analyzed; through the simulation and optimization of the parameters of the optical waveguide grating for input and output, improve the coupling efficiency of the grating; the core unit of the micro ring resonator is analyzed. At the end of the micro resonator integrated unit was optimized by L-Edit software. By using electron beam lithography and sense Coupled plasma etching process should be completed in vertically coupled strip optical waveguide grating as the input optical signal output and the micro ring resonator, transmission characteristics of microring resonator are analyzed, the quality factor of 105 high Q micro ring resonator.2, structural properties of graphene were analyzed in theory the theoretical analysis, simulation of the graphene Fermi level, dielectric constant, parameters such as the relationship with voltage variation. By chemical vapor deposition (CVD) on copper substrate grown graphene films, and through the wet transfer to the surface of the silicon waveguide. To solve the more difficult process of graphite graphene nano optical waveguide integrated chip in machining process, and by electron beam evaporation, ALD atomic deposition, UV lithography to achieve the graphical and electrode growth process of graphene films, and finally lead and PCB board Bonding, obtained graphene and nano optical waveguide with the photoelectric modulation chip.3, the micro ring resonator graphene composite structure of electro-optic modulation test design and new gradient processing of micro ring resonator graphene composite structure to enhance the graphene and light interaction, in order to increase the modulation efficiency, measured the modulation depth of up to 26dB, the test results are analyzed in detail. Through optimized calculation of cascade of nano optical waveguide parameters of micro ring resonator, the chip was observed on electromagnetically induced transparency like effect, and the principle is applied to cascaded micro ring electromagnetically induced transparency like effect in electronic control graphene light absorption, and realize the regulation of graphene induced transparency effect on optical waveguide electromagnetic in the experiment, the spectral lines of blue and red shift was analyzed and calculated in detail.

【学位授予单位】：中北大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN761
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本文编号：1409318