6H-SiC(0001)表面graphene逐层生长的分子动力学研究

利用经典分子动力学方法和模拟退火技术分析研究了6H-ＳiC（0001）表面graphene的逐层生长过程及其形貌结构特点．研究表明，经过高温蒸发表面硅原子后，6H-ＳiC（0001）表面的碳原子能够通过自组织过程生成稳定的局部单原子层graphene结构．这种过程类似于6H-ＳiC（0001）表面graphene的形成，其生长和结构形貌演化主要取决于退火温度和表面碳原子的覆盖程度． 研究发现，当退火温度高于1400K时，6H-ＳiC（0001）表面碳原子能形成局部的单原子层graphene结构．这一转变温 关键词： graphene 碳化硅 分子动力学

Growth of graphene structure on 6H-SiC(0001): Molecular dynamics study

The growth process of graphene structure on 6H-SiC(0001) surface has been studied using the classical molecular dynamics (MD) simulation and the simulated annealing technique. We show that carbon atoms of the 6H-SiC(0001) subsurface after sublimation of Si atoms can be self-organized to form local monolayer graphene structures. This process is similar to the formation of graphene on the 6H-SiC(0001) surface, depending strongly on annealing temperature and coverage of carbon atoms on the SiC (0001-)surface. The local graphene structures can be formed on 6H-SiC(0001)as the annealing temperature is around 1400 K. This transformation temperature is in good agreement with experimental observations (1080 ℃), but is lower than that of growing graphene on SIC(0001) surface (T≈ 1450 K). In addition, not only single layer but also bilayer graphene structure can be formed, associated with the increase of the coverage of carbon atoms on SIC(0001)surface.