4H-SiC纳米结构调制及应用研究

发布时间：2018-04-09 19:23

本文选题：4H-SiC　切入点：介孔阵列　出处：《上海师范大学》2015年硕士论文

【摘要】：作为第三代半导体的碳化硅(Si C)材料,具有多项优异的性能,诸如宽禁带、高热导率、高击穿场强等,这使得它能代替硅(Si)材料在高温、高频、大功率等有特殊需求的领域得到应用。在硅基芯片集成化要求日益提高的背景下,硅基微结构调控工艺已较为成熟。虽然近几年通过各种合成方法制备了Si C纳米结构,但晶型以3C-Si C为主,4H-Si C纳米结构的制备、调控产逐渐变为现实。如今,4H-Si C可以商业化生产,这使得基于该晶圆的器件可实现量产。为了实现4H-Si C纳米结构与4H-Si C基SOC的结合,本研究将电化学刻蚀工艺运用到4H-Si C纳米结构的调控中。本论文开展的主要工作如下:在n-Si电化学刻蚀实验研究的基础上,建立了少子漂移模型,给出了n-Si刻蚀过程中产生侧蚀的理论解释,为n型4H-Si C电化学刻蚀提供了理论指导。在n型4H-Si C电化学刻蚀研究中,通过引入脉冲电流源,解决了“C面刻蚀得到的柱状介孔孔径随刻蚀深度而加宽”的难题,制备出孔径一致的均匀介孔阵列。在n型4H-Si C纳米线制备研究中,通过电化学刻蚀方法,成功制备出晶型单一的4H-Si C纳米线阵列。通过改变电流模式,首次实现了对纳米线长度及形貌的调控,纳米线长度可控制在纳米至微米量级。应用方面,碳化硅材料占据高温应用的潜在价值,在柔性场发射与柔性超级电容器研究热潮的大背景下,本研究以高温柔性/高温场发射阴极和超级电容器的研制为最终目标。工作主要对纳米结构的4H-Si C进行了相关性能的表征。在4H-Si C纳米线阵列场发射性能表征中,当阴阳极间距为700?m时,得到场增强因子最大值7901,开启电压为0.86 V?μm-1。在电容特性的表征中,4H-Si C均匀介孔阵列的比电容达450?F?cm-2。
[Abstract]:As a third-generation semiconductor, silicon carbide (sic) has many excellent properties, such as wide band gap, high thermal conductivity, high breakdown field strength, etc., which makes it possible to replace Si Si Si) materials at high temperature and high frequency.High power and other fields with special needs have been applied.In the background of increasing integration requirements of silicon-based chips, silicon-based micro-structure control technology has been more mature.In recent years, sic nanostructures have been prepared by various synthetic methods, but the preparation of 4H-Si C nanostructures with 3C-Si C as the main crystal type has gradually become a reality.Today, 4 H-Si C can be commercially produced, which allows bulk production of devices based on the wafer.In order to combine 4H-Si C nanostructures with 4H-Si C based SOC, the electrochemical etching process was applied to the regulation of 4H-Si C nanostructures.The main work of this thesis is as follows: based on the experimental study of n-Si electrochemical etching, a minority carrier drift model is established, and the theoretical explanation of side etching in the process of n-Si etching is given, which provides theoretical guidance for n-type 4H-Si C electrochemical etching.In the study of n-type 4H-Si C electrochemical etching, the problem of "the cylindrical mesoporous aperture widened with etching depth" was solved by introducing pulse current source, and a uniform mesoporous array with uniform pore size was prepared.In the preparation of n-type 4H-Si C nanowires, a single 4H-Si C nanowire array was successfully fabricated by electrochemical etching.By changing the current mode, the length and morphology of nanowires are adjusted for the first time. The length of nanowires can be controlled in the order of nanometers to microns.In application aspect, silicon carbide material occupies the potential value of high temperature application. Against the background of the research boom of flexible field emission and flexible supercapacitor, the final goal of this study is to develop high temperature flexible / high temperature field emission cathode and supercapacitor.The properties of nanostructured 4H-Si C were characterized.In the field emission characterization of 4H-Si C nanowire array, when the distance between cathode and cathode is 700m, the maximum field enhancement factor is 7901 and the starting voltage is 0.86V? 渭 m -1.In the characterization of capacitance characteristics, the specific capacitance of 4H-Si C homogenous mesoporous array is up to 450 F ~ (-1) C ~ (m ~ (-2)).
【学位授予单位】：上海师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O469

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