Realizing an Omega-Shaped Gate MoS₂ Field-Effect Transistor Based on a SiO₂/MoS₂ Core–Shell Heterostructure

Abstract

Substantial progress has been made in the experimental synthesis of large-area two-dimensional transition metal dichalcogenide (TMD) thin films in recent years. This has provided a solid basis to build non-planar structures to implement the unique electrical and mechanical properties of TMDs in various nanoelectronic and mechano-electric devices, which, however, has not yet been fully explored. In this work, we demonstrate the fabrication and characterization of MoS₂ field-effect transistors (FETs) with an omega (Ω)-shaped gate. The FET is built based on the SiO₂/MoS₂ core-shell heterostructure integrated using atomic layer deposition (ALD) technique. The MoS₂ thin film has been uniformly deposited by ALD as wrapping the SiO₂ nanowire forming the channel region, which is further surrounded by the gate dielectric and the Ω-gate. The device has exhibited n-type behavior with effective switching comparable to the reference device with a planar MoS₂ channel built on a SiO₂/Si substrate. Our work opens up an attractive avenue to realize novel device structures utilizing synthetic TMDs, thereby broadening their potential application in future advanced nanoelectronics.