Electrical Properties of Dual-Gate, Ultrashort Monolayer WS2 Transistors

We report on the observation of record high current density in ultrashort dual-gate (DG) monolayer chemical vapor deposition WS
₂
field-effect transistors (FETs). The DG FETs were defined by means of a seed layer for depositing the top-gate high-κ dielectric. By using semi-metallic Sb as contacts, we achieved a low contact resistance of 550 Ω·μm. A statistical study was conducted for 150 FETs with scaling channel length (
L
_ch
) from 1 μm down to 15 nm. A record high on-state current of 630 μA/μm was demonstrated at room temperature (680 μA/μm at 8 K) with a 1 V bias. This work unveils the tremendous potential of monolayer WS
₂
for ultimate downscaling solutions in future nanoelectronics.