Ultra-sensitive heterojunction double gate BioTFET device for SARS-CoV-2 biomolecules detection

The persisting SARS-CoV-2 genetic mutation could unintentionally increase human transmission, mortality, and aggravation. Since no specific pharmaceutical therapies or vaccinations exist, rapid detection and successful treatment are essential for managing the COVID-19 pandemic. BioTFETs exhibit superior sensitivity and faster response times than bioFETs, which are more vulnerable to substantial subthreshold swing and short-channel effects. This article presents the Dielectrically Modulated-Double Gate-Heterojunction-Tunnel FET-based biosensor (DG-bioHTFET) specifically engineered to identify and detect the nucleocapsid protein and RNA biomolecules with specific permittivity (k) of SARS-CoV-2 biomolecules embedded in the nanogaps. At V_gs = 1.5 V, the proposed device achieves a drain current (I_ds) of 2.32 × 10^{- 5} A/µm. At k = 5 and k = 3.64, the I_ON/I_OFF ratios are 3.550 × 10⁵ and 3.403 × 10⁵, respectively. The data suggest that the device exhibits increased sensitivity to biomolecules possessing elevated dielectric constants. It is feasible to design ultra-sensitive TFET biosensors as a bio-recognition unit, which offers the benefits of rapid label-free detection and high sensitivity. The device exhibits superior performance in terms of high drain current with enhanced sensitivity for precise biosensing applications.