Lee Jong-Hwan, Song Jaekwang, Shin Dong Heon, Park Seoungwoong, Kim Hwa Rang, Cho Sung-Pyo, Hong Byung Hee
Department of Chemistry, Seoul National University, Seoul 08826, Korea.
Graphene Research Center, Advanced Institute of Convergence Technology, Suwon 16229, Korea.
ACS Appl Mater Interfaces. 2021 Nov 17;13(45):54536-54542. doi: 10.1021/acsami.1c15648. Epub 2021 Nov 3.
Two-dimensional materials have attracted great attention for their outstanding electronic properties. In particular, molybdenum disulfide (MoS) shows great potential as a next-generation semiconductor due to its tunable direct bandgap with a high on-off ratio and extraordinary stability. However, the performance of MoS synthesized by physical vapor deposition has been limited by contact resistance between an electrode and MoS, which determines overall device characteristics. Here, in order to reduce the contact resistance, we use in situ sulfurization of Mo by HS gas treatment masked by a patterned graphene gas barrier, so that the Mo channel area can be selectively formed, resulting in a gradual edge contact between Mo and MoS. Compared with field-effect transistors with a top contact between the Au/Ti electrode and the MoS channel, a gradual edge contact between the Mo electrode and the MoS channel provides a considerably enhanced electrical performance.
二维材料因其出色的电子特性而备受关注。特别是，二硫化钼（MoS）由于其具有可调节的直接带隙、高开关比和非凡的稳定性，作为下一代半导体显示出巨大潜力。然而，通过物理气相沉积合成的MoS的性能受到电极与MoS之间接触电阻的限制，该接触电阻决定了整个器件的特性。在此，为了降低接触电阻，我们通过由图案化石墨烯气体屏障掩蔽的HS气体处理对Mo进行原位硫化，从而可以选择性地形成Mo沟道区域，导致Mo与MoS之间形成渐变边缘接触。与Au/Ti电极和MoS沟道之间具有顶部接触的场效应晶体管相比，Mo电极和MoS沟道之间的渐变边缘接触提供了显著增强的电学性能。
