School of Physics and Electronics Science, Hunan University of Science and Technology, Xiangtan 411201, People's Republic of China.
Hunan Provincial Key Laboratory of Intelligent Sensors and New Sensor Materials, Xiangtan 411201, Hunan, People's Republic of China.
Phys Chem Chem Phys. 2023 Mar 29;25(13):9548-9558. doi: 10.1039/d3cp00009e.
The rapid rise of two-dimensional (2D) materials has aroused increasing interest in the fields of microelectronics and optoelectronics; various types of 2D van der Waals heterostructures (vdWHs), especially those based on MoS, have been widely investigated in theory and experiment. However, the interfacial properties of MoS and the uncommon crystal surface of traditional three-dimensional (3D) metals are yet to be explored. In this paper, we studied heterostructures composed of MoS and metal(001) slabs, based on the first-principles calculations, and we uncovered that MoS/Au(001) and MoS/Ag(001) vdWHs reveal Schottky contacts, and MoS/Cu(001) belongs to Ohmic contact and possesses ultrahigh electron tunneling probability at the equilibrium distance. Thus, the MoS/Cu(001) heterostructure exhibits the best contact performance. Further investigations demonstrate that external longitudinal strain can modulate interfacial contact to engineer the Schottky-Ohmic contact transition and regulate interfacial charge transport. We believe that it is a general strategy to exploit longitudinal strain to improve interfacial contact performance to design and fabricate a multifunctional MoS-based electronic device.
二维（2D）材料的迅速崛起引起了微电子学和光电子学领域的极大兴趣；各种类型的二维范德华异质结构（vdWHs），特别是基于 MoS 的异质结构，在理论和实验上都得到了广泛的研究。然而，MoS 的界面性质和传统三维（3D）金属的不常见晶体表面尚未得到探索。在本文中，我们基于第一性原理计算研究了由 MoS 和金属（001）片组成的异质结构，揭示了 MoS/Au（001）和 MoS/Ag（001）vdWH 呈现肖特基接触，而 MoS/Cu（001）属于欧姆接触，在平衡距离处具有超高的电子隧穿概率。因此，MoS/Cu（001）异质结表现出最佳的接触性能。进一步的研究表明，外部纵向应变可以调制界面接触，以实现肖特基-欧姆接触转变，并调节界面电荷输运。我们相信，利用纵向应变来改善界面接触性能是设计和制造多功能 MoS 基电子器件的一种通用策略。
