IEEE EDS DU

Promoting excellence in research and learning in the area of electron devices

Promoting excellence in research and learning in the area of electron devices

Negative Capacitance Gate-All-Around Tunnel FETs for Highly Sensitive Label-Free Biosensors

Abstract: We propose a nanoscale, highly sensitive and label-free biosensor based on negative capacitance gateall-around tunnel field-effect transistor (NC-GAA-TFET). NC-GAA-TFETs provide steeper, sub-60 mV/dec subthreshold swing (SS) and higher drive current compared with the conventional gate-all-around tunnel field-effect transistor (GAA-TFETs). The combination of differential voltage amplification, due to the negative capacitance (NC) of the gate ferroelectric, and the quantum mechanical band-toband tunneling (BTBT) effect leads to a significant boost in current sensitivity (SI) compared with the state-of-theart field-effect transistor (FET)-based sensing devices. 1-D Landau–Khalatnikov (L-K) equations are solved numerically and integrated with 3-D technology computer-aided design (TCAD) simulations to evaluate the sensor performance. The results show that the proposed sensor can achieve SS down to 27 mV/dec. The subthermal SS can be maintained over five decades of current leading to reduced power consumption in the weak inversion region and achieving SI as high as ∼106 and ∼105 for detecting biomolecules and pH changes, respectively. In addition, NC-GAA-TFETs provide ∼7× higher signal-to-noise ratio (SNR) than their baseline counterparts which make NC-GAA-TFETs promising candidates for low noise and ultrasensitive biosensing platforms.

DOI: 10.1109/TED.2021.3129711