Sub-1nm EOT WS 2 -FET with I DS > 600μA/μm at V DS =1V and SS G =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.