Collaborative Research: Impurity Incorporation into Epitaxial Graphene on SiC

技术描述：本研究项目的目标是开发一种新的方法，在碳化硅衬底上生长的石墨烯中放置受控数量的替代杂质，对掺杂结构进行物理和电子表征，并评估薄膜性能的变化。在石墨烯形成之前，杂质被注入到碳化硅晶片中。对晶片进行退火热处理，使杂质分布接近表面。然后通过升华硅生长石墨烯，同时将杂质驱动到石墨烯薄膜中。在此过程之后，用表面分析技术和电输运测量来表征杂质的分布。如果成功，该方法还可以应用于其他二维材料。非技术说明：石墨烯是一种以蜂窝晶格结构结合在一起的单层碳原子，具有独特的电学和力学性能。要有效利用这些特性，需要在薄膜中加入预定数量的杂质原子(掺杂)。该项目开发了一种新的方法，将受控数量的原子合并到石墨烯的单个原子层中，并在跨学科环境中提供研究生培训。此外，明尼苏达大学和罗格斯大学的本科生以及在佐治亚理工学院工作的高中教师在该项目中获得直接的实践研究经验，以及在主要研究人员教授的课程中从该项目中获得学习材料和新的理解。

Technical Description: The goal of this research project is to develop a novel method to place controlled amounts of substitutional impurities into graphene grown on SiC, to physically and electronically characterize the doped structures, and to evaluate the changes in the film's properties. Impurities are implanted into a SiC wafer prior to graphene formation. The wafer is annealed to bring the impurity distribution near the surface. Then graphene is grown by sublimation of Si, simultaneously driving the impurities into the graphene film. After this process, the impurity distribution is characterized by surface analytical techniques as well as by electrical transport measurements. If successful, the method can also be applied to other two-dimensional materials.Non-technical Description: Graphene, a single layer of carbon atoms bound together in a honeycomb lattice structure, has unique electrical and mechanical properties. Effective use of these properties requires the inclusion of predetermined amounts of impurity atoms (doping) in the films. The project develops a new method to incorporate controlled amounts of atoms into a single atomic layer of graphene, and provides graduate student training in an interdisciplinary environment. In addition, undergraduate students at the University of Minnesota and at Rutgers University, as well as high school teachers working at Georgia Tech, obtain direct hands-on research experience in the project as well as study materials and new understanding resulting from the project in courses taught by the principal investigators.