KENBIKYO Vol.53▶No.2 2018
■Feature Articles: Exploring the Nanostructure of Low Dimensional Materials

Synthesis and Nanocharacterization of Two-Dimensional Materials

Daisuke Fujita

Abstract: Two-dimensional materials consisting of mono-atomic layer are attracting a great interest as fundamental materials of next-generation high-performance semiconductor devices due to new physical properties and functionality. In this paper, we will focus on graphene in particular, while also mentioning a single layer h-BN nanosheet. We will outline the methods of synthesis through solid surfaces such as surface segregation and surface reaction of doped elements. The optical and electronic properties of graphene depend on the number of layers, the dopant, the defect and the bond with the substrate. Since monolayer, bilayer, and tri-layer graphene nanosheets show different electronic states and functions, specifying the number of graphene layers is indispensable for material research focusing on novel device applications. Therefore, confocal Raman microscopy, scanning tunneling microscopy, scanning Auger microscopy, helium ion microscopy, and Kelvin probe force microscopy, which can perform microscopic analyses of structure and physical properties such as layer number, atomic structure, local density of states, chemical state, work function and so on, are introduced with the actual examples.

Key words: two-dimensional material, graphene, surface monolayer phase, scanning probe microscopy, nanocharacterization