Sun Xingxia, Zhu Chenguang, Liu Huawei, Zheng Biyuan, Liu Yong, Yi Jiali, Fang Lizhen, Liu Ying, Wang Xingwang, Zubair Muhammad, Zhu Xiaoli, Wang Xiao, Li Dong, Pan Anlian
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Materials Science and Engineering, Hunan University, Changsha 410082, China.
Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Materials Science and Engineering, Hunan University, Changsha 410082, China.
Sci Bull (Beijing). 2020 Dec 15;65(23):2007-2013. doi: 10.1016/j.scib.2020.06.033. Epub 2020 Jun 23.
The newly emerged two-dimensional (2D) semiconducting materials, owning to the atomic thick nature and excellent optical and electrical properties, are considered as potential candidates to solve the bottlenecks of traditional semiconductors. However, the realization of high performance 2D semiconductor-based field-effect transistors (FETs) has been a longstanding challenge in 2D electronics, which is mainly ascribing to the presence of significant Schottky barrier (SB) at metal-semiconductor interfaces. Here, an additional contact gate is induced in 2D ambipolar FET to realize near ideal reconfigurable FET (RFET) devices without restrictions of SB. Benefitting from the consistently high doping of contact region, the effective SB height can be maintained at ultra-small value during all operation conditions, resulting in the near ideal subthreshold swing (SS) values (132 mV/decade for MoTe RFET and 67 mV/decade for WSe RFET) and the relatively high mobility (28.6 cm/(V s) for MoTe RFET and 89.8 cm/(V s) for WSe RFET). Moreover, the flexible control on the doping polarity of contact region enables the remodeling and switching of the achieved unipolar FETs between p-type mode and n-type mode. Based on such reconfigurable behaviors, high gain complementary MoTe inverters are further realized. The findings in this work push forward the development of high-performance 2D semiconductor integrated devices and circuits.
新出现的二维（2D）半导体材料，由于其原子厚度特性以及优异的光学和电学性能，被视为解决传统半导体瓶颈的潜在候选材料。然而，实现高性能的基于二维半导体的场效应晶体管（FET）一直是二维电子学中长期存在的挑战，这主要归因于金属 - 半导体界面处存在显著的肖特基势垒（SB）。在此，在二维双极FET中引入额外的接触栅极，以实现不受SB限制的近乎理想的可重构FET（RFET）器件。受益于接触区域持续的高掺杂，有效SB高度在所有操作条件下都能保持在超小值，从而得到近乎理想的亚阈值摆幅（SS）值（MoTe RFET为132 mV/十倍频程，WSe RFET为67 mV/十倍频程）以及相对较高的迁移率（MoTe RFET为28.6 cm²/(V·s)，WSe RFET为89.8 cm²/(V·s)）。此外，对接触区域掺杂极性的灵活控制能够实现所制备的单极FET在p型模式和n型模式之间的重塑和切换。基于这种可重构行为，进一步实现了高增益互补MoTe反相器。这项工作中的发现推动了高性能二维半导体集成器件和电路的发展。
