Steep‐Slope Monolayer HgBr MOSFETs With Sub‐60 mV/dec Subthreshold Swing Through Inherent Hot Carrier Tail Cutoff

ABSTRACT Steep‐slope field‐effect transistors exhibiting sub‐60 mV/dec subthreshold swing ( SS ) are heralded as a promising approach to minimizing the power consumption of electronic devices. Here we demonstrate sub‐60 mV/dec SS and high on‐current can be obtained simultaneously in monolayer HgBr transistors without sophisticated source engineering. The sub‐60 mV/dec SS is attributed to the isolated conduction band, which cuts off the thermal tail contribution and makes a super‐exponential decline in carrier distribution. In addition, high on‐current is maintained through the thermal emission mechanism. A steep SS of 34 mV/dec is achieved at 5 nm under a supply voltage of 0.5 V, and on‐current is as high as 343 and 1478 µA/µm for low‐power and high‐performance applications, respectively. Excellent device performance is further validated by comparing the figure of merits and circuit‐level parameters. Our findings indicate that monolayer HgBr is promising for developing steep‐slope transistors and deserves continued attention in the future.