Title: | Semiconducting Graphene on Silicon from First-Principles Calculations |
Authors: | Xuejie Dang,† Huilong Dong,† Lu Wang, Yanfei Zhao, Zhenyu Guo, Tingjun Hou, Youyong Li,* and Shuit-Tong Lee* |
Institution: | Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China |
Abstract: | Graphene is a semimetal with zero band gap, which makes it impossible to turn electric conduction off below a certain limit. Transformation of graphene into a semiconductor has attracted wide attention. Owing to compatibility with Si technology, graphene adsorbed on a Si substrate is particularly attractive for future applications. However, to date there is little theoretical work on band gap engineering in graphene and its integration with Si technology. Employing first-principles calculations, we study the electronic properties of monolayer and bilayer graphene adsorbed on clean and hydrogen (H)-passivated Si (111)/Si (100) surfaces. Our calculation shows that the interaction between monolayer graphene and a H-passivated Si surface is weak, with the band gap remaining negligible. For bilayer graphene adsorbed onto a H-passivated Si surface, the band gap opens up to 108 meV owing to asymmetry introduction. In contrast, the interaction between graphene and a clean Si surface is strong, leading to formation of chemical bonds and a large band gap of 272 meV. Our results provide guidance for device designs based on integrating graphene with Si technology. |
IF: | 12.881 |
Link: | http://pubs.acs.org/doi/abs/10.1021/acsnano.5b03722 Editor: Danting Xiang |