Steep Slope p-type 2D WSe2 Field-Effect Transistors with Van Der Waals Contact and Negative Capacitance

摘要

Steep-slope p-type 2D WSe₂ back-gated field-effect transistors (FETs) are realized by using van der Waals Pt-WSe₂ contact and HfZrO₂/ Al₂O₃ as the dielectric layer. The van der Waals Pt-WSe₂ contact is free from disorder and Fermi level pinning and decreases the subthreshold slope. The WSe₂ NCFET with van der Waals contact shows low subthreshold slope for both forward and reverse gate voltage sweep (the minimum SS_forward = 18.2 mV/dec and SS_reverse = 44.1 mV/dec) with a hysteresis as small as 20 mV at subthreshold region.