Directly grown Te nanowire electrodes and soft plasma etching for high-performance MoTe2 field-effect transistors

Abstract

Contact tailoring for two-dimensional (2D) transition metal dichalcogenides (TMDs) to achieve high-performance devices remains a challenge. Fermi-level pinning at 2D TMD–metal contacts leads to a Schottky barrier for contacts. In addition, when there are no dangling bonds between 2D TMDs and contacts, the contact resistance increases. In this study, Te nanowire (NW) contacts were employed for a MoTe2 p-channel of enhancement mode field-effect transistor (FET). The Te NWs were directly grown on 2D MoTe2 film by metal–organic chemical vapor deposition and selectively etched by a soft plasma etching technique for contact isolation. Using t-Te NW contacts on three-atomic-layer MoTe2, a highly effective field-effect mobility of 543.9 cm2/Vs, as well as ohmic contacts and atomic hybridization, was achieved. These results of t-Te NW electrodes provide a novel device structure for p-type 2D TMD transistors with excellent performances. Further, they offer a practical guideline for wafer-scale 2D TMD-based high-performance electronics and optoelectronics.