The structural and electronic properties of van der Waals (vdW) heterostructrue constructed by graphene and graphene-like germanium carbide were investigated by computations based on density functional theory with vdW correction. The results showed that the Dirac cone in graphene can be quite well-preserved in the vdW heterostructure. The graphene/graphene-like germanium carbide interface forms a p-type Schottky contact. The p-type Schottky barrier height decreases as the interlayer distance decreases and finally the contact transforms into a p-type Ohmic contact, suggesting that the Schottky barrier can be effectively tuned by changing the interlayer distance in the vdW heterostructure. In addition, it is also possible to modulate the Schottky barrier in the graphene/graphene-like germanium carbide vdW heterostructure by applying a perpendicular electric field. In particular, the positive electric field induces a p-type Ohmic contact, while the negative electric field results in the transition from a p-type to an n-type Schottky contact. Our results demonstrate that controlling the interlayer distance and applying a perpendicular electric field are two promising methods for tuning the electronic properties of the graphene/graphene-like germanium carbide vdW heterostructure, and they can yield dynamic switching among p-type Ohmic contact, p-type Schottky contact, and n-type Schottky contact in a single graphene-based nanoelectronics device.
|Original language||English (US)|
|State||Published - Mar 26 2019|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: Sake Wang would like to acknowledge the funding support from the National Science Foundation for Young Scientists of China (grant number 11704165) and the Science Foundation of Jinling Institute of Technology (grant number 40620064). Chongdan Ren would like to acknowledge the funding support from the National Natural Science Foundation of China (grant number 11864047), the Science Foundation of Guizhou Science and Technology Department (grant number QKHJZ2150), and the Science Foundation of Guizhou Provincial Education Department (grant number QJHKYZ092).