Sub-1nm EOT WS2-FET with IDS > 600μA/μm at VDS=1V and SS < 70mV/dec at LG=40nm

Ultra-scaled WS
₂
field-effect transistors (FETs) with excellent on-state and off-state performance are reported. A record high on-state current (I
_ON
) and ultra-low contact resistance (R
_C
) were achieved in a double-gated FET at a much scaled overdrive voltage (V
_OV
=V
_GS
-V
_TH
), reaching > 600 (μA/μm) at V
_DS
=1V and V
_OV
=2V with a contact resistance of R
_C
~ 500 (Ω*μm). We report statistics of more than 50 FETs with varying channel lengths, showing excellent off-state behaviors with small threshold voltage (V
_TH
) variations, near-ideal subthreshold slope (SS), and small drain-induced barrier lowering (DIBL). Various channel thicknesses (T
_CH
) ranging from 2.1nm to 7nm were carefully evaluated in terms of short channel effects (SCEs) and on-state current, and a WS
₂
body thickness of 2.1nm (3 layers, the thinnest in our statistics) shows the best performance in both on-state and off-state.