高定向SiC纳米阵列温和制备与精细控制及其电子发射特性

SiC, as an important third-generation wide bandgap semiconductor, has a series of superior physical performances, which is considered as an excellent candidate for the field emitters. The key to push forward them to be practically applied in display and vacuum electronics is to realize the controlled growth of nanoarrays. However, up to date, the growth of SiC field emitters are often carried out under the harsh conditions such as high temperatures and high pressures, which is considered as the grand challege to realize the controllabe and repeatable growth of SiC low-dimensional nanostructures. In the present work, aimed to the exploration of novel SiC field emitters with totally high performances, we will firstly realize the controlled growth of the SiC nanoarrays via the technique of anode electrochemical etching under the air conditions. Subsequently, the bamboo-tip-shaped SiC nanoarrays with controlled densities and aspect ratios will be accomplished by precisely tailoring the experimental parameters. The as-fabricated SiC nanoarrays might take advantage of tailoring the energy band, local field enhancement effect, increasing the electron emission cites, and enhanced field enhancement factor, as well as limited screening effect, which lead to the synergistic enhancement of the electron emission ability. This project will be carried out systematically to characterize the electron emission performances of SiC nanoarrays, clarify and optimize the relationship of the technology, nanoarrays structures and field emission properties, and disclose the mechanism of the electron emission. Current work might put forward the exploration of SiC cathodes with low turn on fields and high electron emission stability, and could provide some scientific data and basic theories for their technology research and potential applications.

第三代宽带系半导体SiC，具有系列优异的物理特性，是场发射阴极代表性材料之一。为推动其在显示和真空电子等领域的广泛应用，纳米阵列的生长是关键所在。然而，当前SiC场发射阴极的生长，一般均需高温高压等苛刻条件，严重影响其可控和可重复性。本项目拟以新颖高效SiC场发射阴极研发为目标，围绕其纳米阵列的温和制备及其结构精细控制开展工作，采用阳极电化学刻蚀，在室温常压下实现纳米阵列的生长；然后通过工艺优化，实现竹尖状纳米阵列生长及其密度和长径比的精细调控，以期在规避屏蔽效应的同时，集能带调控、局域场增强效应、增加电子发射点和强化场增强因子等多种手段为一体，协同强化电子发射能力。项目将系统探究SiC纳米阵列的电子发射特性，阐明刻蚀工艺-结构-性能之间的内在关联并优化，揭示其电子发射机理，实现兼具低开启电场和高电子发射稳定性的SiC场发射阴极的研发，具有显著的科学意义和潜在的应用前景。

第三代宽带系半导体SiC，具有系列优异的物理特性，是场发射阴极代表性材料之一。为推动其在显示和真空电子等领域的广泛应用，纳米阵列的生长是关键所在。然而，SiC场发射阴极的生长，一般均需高温高压等苛刻条件，严重影响其可控和可重复性。本项目以新颖高效SiC场发射阴极研发为目标，围绕其纳米阵列的温和制备及其结构精细控制开展了系统研究工作，采用阳极电化学刻蚀，在室温常压下实现了纳米阵列的生长；然后通过工艺优化，实现纳米阵列形貌、密度、长径比等的精细调控，在规避屏蔽效应的同时，能够集能带调控、局域场增强效应、增加电子发射点和强化场增强因子等多种手段为一体，实现阴极电子发射能力的协同强化。项目系统探究了SiC纳米阵列的电子发射特性，阐明刻蚀工艺-结构-性能之间的构效关系并优化，揭示了电子发射机理，实现兼具低开启电场和高稳定性的SiC场发射阴极的研发。.研究工作圆满完成了项目拟定的各项指标。发表了SCI收录论文15篇(原定指标：8篇)，均为Top期刊，影响因子均大于3(原定指标：影响因子大于3的5篇)，影响因子大于10的2篇(原定指标：力争发表影响因子大于10的1篇)，同时应邀为SCI一区Top期刊Prog. Mater. Sci. (2019, 104: 138-214 (影响因子: 31.560)) 和J. Mater. Chem. C (2017, 5: 10682-10700. (影响因子: 7.059))撰写综述论文2篇；获授权发明专利3项(原定指标：申请国家发明专利3 项)。.本项目所实现的在室温常压的温和条件下制备高定向SiC纳米阵列的精细调控原理和技术，将很大程度上拓展SiC纳米结构的制备及其广泛应用，同时对其他半导体纳米阵列材料的可控生长具备一定的借鉴意义；所研发的SiC纳米阵列的电子发射特性处国际领先水平，在各类真空电子和平板显示领域，具有一定的潜在应用前景。