Over the past decade, the field of two-dimensional (2D) layered materials has surged, promising a new platform for studying diverse physical phenomena that are scientifically intriguing and technologically relevant. Contacts are the communication links between these 2D materials and the three-dimensional world for probing and harnessing their exquisite electronic properties. However, fundamental challenges related to contacts often limit the ultimate performance and potential of 2D materials and devices. This article provides a comprehensive overview of the basic understanding and importance of contacts to 2D materials and various strategies for engineering and improving them. In particular, we elucidate the phenomenon of Fermi level pinning at the metal/2D contact interface, the Schottky versus Ohmic nature of the contacts and various contact engineering approaches including interlayer contacts, phase engineered contacts, and basal versus edge plane contacts, among others. Finally, we also discuss some of the relatively under-addressed and unresolved issues, such as contact scaling, and conclude with a future outlook.

中文翻译：

---

2D材料和设备的接触工程

在过去的十年中，二维（2D）分层材料的领域激增，为研究具有科学吸引力和技术相关性的各种物理现象提供了一个新的平台。接触是这些2D材料与三维世界之间的通信链接，用于探测和利用其精美的电子属性。但是，与接触有关的基本挑战通常会限制2D材料和设备的最终性能和潜力。本文提供了对2D材料接触的基本理解和重要性以及进行工程设计和改进的各种策略的全面概述。特别是，我们阐明了在金属/ 2D接触界面上的费米能级钉扎现象，肖特基与触点的欧姆性质以及各种触点工程方法，包括层间触点，相工程触点以及基面与边缘平面触点等。最后，我们还讨论了一些相对未解决且尚未解决的问题，例如接触扩大，并得出了未来展望。