MoS ₂ transistors gated by ferroelectric HfZrO ₂ with MoS ₂ /mica heterojunction interface

Abstract

Abstract Two-dimensional (2D) molybdenum disulfide (MoS 2 ) field-effect transistor (FET) gated by negative capacitance (NC) is a promising architecture to overcome the thermionic limit and thus reduce device consumption. Here, top-gated MoS 2 NCFETs have been prepared by transferring a mica flake on MoS 2 channel to form a van der Waals heterojunction interface, together with a ferroelectric HfZrO 2 (HZO) deposited on mica. Stable NC effects are demonstrated for MoS 2 NCFETs. The MoS 2 NCFETs integrated with mica/HZO gate stack provide competitive electrical characteristics when they are applied with a gate voltage sweep-width in the range of 1−3 V and a sweep-rate from 0.01 to 0.2 V s −1 , including steep-slope of sub 60 mV dec −1 in four orders of magnitude of drain current, on/off current ratio over 10 6 , and small hysteresis-width less than 50 mV. Outstanding performance should be ascribed to damage-free properties of mica/MoS 2 van der Waals interface and capacitance matching between the HZO ferroelectric and mica dielectric. The results confirm the promising nature of mica/HZO gate stack and potential applications for future electronics.