Physics and Astronomy Department, Michigan State University, East Lansing, Michigan 48824, USA.
Phys Rev Lett. 2013 Apr 26;110(17):176805. doi: 10.1103/PhysRevLett.110.176805.
We use ab initio density-functional calculations to determine the interaction of a graphene monolayer with the Si(111) surface. We find that graphene forms strong bonds to the bare substrate and accommodates the 12% lattice mismatch by forming a wavy structure consisting of free-standing conductive ridges that are connected by ribbon-shaped regions of graphene, which bond covalently to the substrate. We perform quantum transport calculations for different geometries to study changes in the transport properties of graphene introduced by the wavy structure and bonding to the Si substrate. Our results suggest that wavy graphene combines high mobility along the ridges with efficient carrier injection into Si in the contact regions.
我们使用从头算密度泛函理论计算来确定单层石墨烯与 Si(111)表面的相互作用。我们发现，石墨烯与裸露的基底形成强烈的键合，并通过形成由自由-standing 导电脊组成的波浪形结构来适应 12%的晶格失配，这些脊由与基底共价键合的石墨烯带状区域连接。我们对不同的几何形状进行量子输运计算，以研究波浪形结构和与 Si 基底键合引入的石墨烯输运性质的变化。我们的结果表明，波浪形石墨烯在脊上具有高迁移率，并且在接触区域中有效地将载流子注入 Si。
