Over the past decade, two-dimensional semiconductors (2DSCs) have aroused wide interest due to their extraordinary electronic, magnetic, optical, mechanical, and thermal properties, which hold potential in electronic, optoelectronic, thermoelectric applications, and so forth. The field-effect transistor (FET), a semiconductor gated with at least three terminals, is pervasively exploited as the device geometry for these applications. For lack of effective and stable substitutional doping techniques, direct metal contact is often used in 2DSC FETs to inject carriers. A Schottky barrier (SB) generally exists in the metal–2DSC junction, which significantly affects and even dominates the performance of most 2DSC FETs. Therefore, low SB or Ohmic contact is highly preferred for approaching the intrinsic characteristics of the 2DSC channel. In this review, we systematically introduce the recent progress made in theoretical prediction of the SB height (SBH) in the 2DSC FETs and the efforts made both in theory and experiments to achieve low SB contacts. From the comparison between the theoretical and experimentally observed SBHs, the emerging first-principles quantum transport simulation turns out to be the most powerful theoretical tool to calculate the SBH of a 2DSC FET. Finally, we conclude this review from the viewpoints of state-of-the-art electrode designs for 2DSC FETs.

在过去的十年中，二维半导体 (2DSCs) 因其非凡的电子、磁、光学、机械和热性能而引起了广泛的兴趣，在电子、光电子、热电应用等方面具有潜力。场效应晶体管 (FET) 是一种具有至少三个端子的门控半导体，被广泛用作这些应用的器件几何结构。由于缺乏有效且稳定的替代掺杂技术，2DSC FET 中经常使用直接金属接触来注入载流子。肖特基势垒 (SB) 通常存在于金属-2DSC 结中，这会显着影响甚至主导大多数 2DSC FET 的性能。因此，对于接近 2DSC 通道的固有特性，非常优选低 SB 或欧姆接触。在这次审查中，我们系统地介绍了最近在 2DSC FET 中 SB 高度 (SBH) 的理论预测方面取得的进展，以及在理论和实验上为实现低 SB 接触所做的努力。从理论和实验观察到的 SBH 之间的比较，新兴的第一性原理量子传输模拟结果证明是计算 2DSC FET 的 SBH 的最强大的理论工具。最后，我们从最先进的 2DSC FET 电极设计的角度总结了这篇评论。新兴的第一性原理量子传输模拟被证明是计算 2DSC FET SBH 的最强大的理论工具。最后，我们从最先进的 2DSC FET 电极设计的角度总结了这篇评论。新兴的第一性原理量子传输模拟被证明是计算 2DSC FET SBH 的最强大的理论工具。最后，我们从最先进的 2DSC FET 电极设计的角度总结了这篇评论。