Band Engineering of Dirac Materials for Device Applications

这项研究建议开发一种复杂程度较低的可扩展方法来调制二维(2D)Dirac材料的能带结构，包括石墨烯、硅烯和过渡金属二卤化物，用于电子和能源技术。用金属纳米结构或聚合物分子对2D Dirac材料进行图案化装饰将被探索为一种有效的手段，在保持2D Dirac系统固有的电学和光学特性的同时，调节2D Dirac系统选定区域的能隙。使用加拿大光源的X射线吸收和发射光谱将对带状工程材料的详细电子结构进行表征，以阐明通过表面修饰在2D材料中打开带隙的机制。这些波段设计的2D狄拉克材料最终将用于生产高性能晶体管和太阳能电池设备。器件运行参数(例如晶体管器件的载流子迁移率和通断比以及太阳能电池器件的能量转换效率)将与表面覆盖率和装饰材料的类型进行定量分析，以实现优化的器件性能。*以下目标将作为半导体Dirac电子学的主要方向：a)研究金属纳米结构的形成(如有必要，随后进行氧化)和有机材料装饰对IV族2D Dirac材料(石墨烯和硅烯)和过渡金属二卤化物(MoS2)能带结构的影响，B)使用选区带状工程材料设计和制造电子和光伏器件架构，以及c)优化器件的电流-电压(I-V)特性。*这项研究计划对加拿大的相关研究领域和行业具有重要意义，因为它不仅将增进我们对低维系统中相对论量子力学现象的基础知识，而且有助于人们克服当前半导体技术的局限性，为后硅电子学做好准备。这项研究对加拿大也很重要，因为它涉及信息和通信技术(ICT)、纳米技术和能源技术，这些都是加拿大科学、技术和创新战略下的优先研发领域。

This research proposes to develop a scalable method with less complexity to modulate the band structure of two dimensional (2D) Dirac materials including graphene, silicene, and transition metal dichalcogenides for applications in electronics and energy technologies. Patterned decoration of 2D Dirac materials with metallic nanostructures or polymer molecules will be explored as an effective mean to tune the energy band gap in selected areas of 2D Dirac systems while preserving their intrinsic electrical and optical properties. The characterization of detailed electronic structure for the band-engineered materials will be conducted using X-ray absorption and emission spectroscopy at the Canadian Light Source to shed light on the mechanism behind the opening of band gap in 2D materials by surface modification. These band-engineered 2D Dirac materials will ultimately be used to produce high performance transistor and solar cell devices. The quantitative analysis of the device operation parameters (for example, carrier mobility and on/off ration for transistor devices and energy conversion efficiency for solar cell devices) with respect to the surface coverage and type of decorating materials will be conducted in order to achieve the optimized device performance.***The following objectives will be pursued as main directions toward semiconductor Dirac electronics: a) investigation of the effect of metallic nanostructure formation (and followed by oxidation if necessary) and organic material decoration on the band structure of group-IV 2D Dirac materials (graphene and silicene) and transition metal dichalcogenide (MoS2), b) design and fabrication of electronic and photovoltaic device architectures using the selected-area band-engineered materials, and c) optimization of the current-voltage (I-V) characteristics of devices. ***This research program is of great importance to allied research field and industries in Canada as it will not only advance our fundamental knowledge of relativistic quantum mechanical phenomena in low dimensional systems but also help people overcome limitations in current semiconductor technology and prepare for post-silicon electronics. This research is also important to Canada as it involves information and communication technologies (ICT), nanotechnology, and energy technologies which are among the areas of R&D priority under Canada's Science, Technology and Innovation Strategy.