Graphene on atomically flat insulating substrates

该项目旨在在清洁，原子有序，电绝缘的基底（如CaF2，CeO2和金刚石）上制备高质量的石墨烯，并对此类系统的物理特性进行基本了解。研究的重点是石墨烯原子尺度结构特性的表征，以及理解和控制石墨烯与底层衬底的相互作用。石墨烯薄膜的特征在于在非接触模式下操作的最高分辨率动态扫描力显微镜（NC AFM）和开尔文探针力显微镜（KPFM）。从原子分辨的测量在薄片的边界，我们希望揭示石墨烯膜和基板之间的注册表，而力成像和光谱的湖泊面积预计将产生有关的石墨烯膜和基板之间的相互作用的信息。该项目的主要目标是（1）改进超高真空中石墨烯的剥离，以在绝缘体表面上产生具有最高结构完整性和均匀性的单层石墨烯的大薄片，（2）石墨烯薄片上或下的缺陷的原子尺度表征，以及在它们的边界处的原子结构和局部表面电势的研究，以及它们与下面的单层膜的配准。

The project aims at preparing high quality graphene on clean, atomically ordered, electrically insulating substrates such as CaF2, CeO2, and diamond and a fundamental understanding of the physical properties of such systems. The focus of investigations is on the characterisation of graphene atomic scale structural properties as well as understanding and controlling the interaction of graphene with the underlying substrate. Graphene films are characterised by highest resolution dynamic scanning force microscopy operated in the non-contact mode (NC AFM) and Kelvin probe force microscopy (KPFM). From atomically resolved measurements at the border of flakes, we expect to reveal the registry between the graphene film and the substrate while force imaging and spectroscopy on the lake area is expected to yield information about the interaction between the graphene film and the substrate. The main goals for the project are (1) the improvement of the exfoliation of graphene in the ultra-high vacuum to produce large flakes of single layer graphene of highest structural perfection and uniformity on insulator surfaces, (2) the atomic scale characterisation of defects on or under the graphene flakes, and at their borders and (3) the study of the atomic structure and the local surface potential of folded graphene films as well as their registry with the underlying single layer film.