Zhang W X, Yin Y, He C
School of Materials Science and Engineering, Chang'an University, Xi'an 710064, China.
Phys Chem Chem Phys. 2020 Nov 25;22(45):26231-26240. doi: 10.1039/d0cp04474a.
Graphene-based van der Waals (vdW) heterostructures composed of two-dimensional transition metal dichalcogenides (TMDs) and graphene show great potential in the design and manufacture of field effect transistors. However, the Schottky barrier generated by the contact between metal and semiconductor hinders the conduction of electrons, so it is necessary to effectively adjust the Schottky barrier and form a low-resistance Ohmic contact. Based on first-principles calculations, graphene/WSSe (G/WSSe) heterostructures have been established and the corresponding electronic properties have been studied. Firstly, these heterostructures form an n-type Schottky contact with a SBH of 0.35 eV and a p-type Schottky contact with a SBH of 0.66 eV at their respective interfaces. In addition, the Schottky contact can be significantly adjusted by changing the interlayer coupling or applying an external biaxial strain, and an Ohmic contact could also be formed under the biaxial strain. This study not only offers a basic understanding of G/WSSe heterostructures, but also provides a reference for the application of G/WSSe heterostructures in optoelectronic and nanoelectronic devices.
由二维过渡金属二硫属化物（TMDs）和石墨烯组成的基于石墨烯的范德华（vdW）异质结构在场效应晶体管的设计和制造中显示出巨大潜力。然而，金属与半导体之间的接触产生的肖特基势垒阻碍了电子传导，因此有必要有效调节肖特基势垒并形成低电阻欧姆接触。基于第一性原理计算，建立了石墨烯/WSSe（G/WSSe）异质结构并研究了其相应的电子特性。首先，这些异质结构在各自界面处形成了肖特基势垒高度（SBH）为0.35 eV的n型肖特基接触和SBH为0.66 eV的p型肖特基接触。此外，通过改变层间耦合或施加外部双轴应变可以显著调节肖特基接触，并且在双轴应变下也可以形成欧姆接触。本研究不仅提供了对G/WSSe异质结构的基本理解，还为G/WSSe异质结构在光电器件和纳米电子器件中的应用提供了参考。
