Dielectrically-Modulated Stacked Nanosheet Schottky TFETs for Biosensing Applications

This work presents the design and analysis of a high-sensitivity Nanosheet Schottky Tunnel Field-Effect Transistors (NS-STFETs) for biosensing applications. The proposed device leverages Schottky source/drain contacts and stacked nanosheet geometry to enhance electrostatic control and tunneling efficiency. Device performance was investigated using Sentaurus TCAD simulations. The biosensor demonstrates promising characteristics, including an ION of 2.43 × 10–5 A, IOFF of 1.33 × 10–18 A, and ION/IOFF of 1013 for protein biomolecules with a dielectric constant of k = 8. Further analysis was carried out to evaluate the influence of biomolecules with varying dielectric constants (k = 1 to 20), different fill factors (25–100%), and positively/negatively charged biomolecules with charge densities from –1011 to +1011. The results confirm that higher fill factors and charged biomolecules have a significant impact on sensitivity, while the device maintains stable operation under various conditions. Overall, the NS-STFET biosensor exhibits high sensitivity, low power consumption, and scalability, making it a strong candidate for next-generation label-free diagnostic platforms.