Realizing an Omega-Shaped Gate MoS Field-Effect Transistor Based on a SiO/MoS Core-Shell Heterostructure.

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 MoS field-effect transistors (FETs) with an omega (Ω)-shaped gate. The FET is built based on the SiO/MoS core-shell heterostructure integrated using atomic layer deposition (ALD) technique. The MoS thin film has been uniformly deposited by ALD as wrapping the SiO 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 MoS channel built on a SiO/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.