Demonstration of Steep Switching Behavior Based on Band Modulation in WSe₂ Feedback Field-Effect Transistor

Feedback field-effect transistors (FBFETs) have been studied to obtain near-zero subthreshold swings at 300 K with a high on/off current ratio ~10¹⁰. However, their structural complexity, such as an epitaxy process after an etch process for a Si channel with a thickness of several nanometers, has limited broader research. We demonstrated a FBFET using in-plane WSe₂ p-n homojunction. The WSe₂ FBFET exhibited a minimum subthreshold swing of 153 mV/dec with 30 nm gate dielectric. Our modeling-based projection indicates that the swing of this device can be reduced to 14 mV/dec with 1 nm EOT. Also, the gain of the inverter using the WSe₂ FBFET can be improved by up to 1.53 times compared to a silicon CMOS inverter, and power consumption can be reduced by up to 11.9%.