Pioneering Precision in Biomolecular Detection with GaAs-Pocket-Hetero-Vertical-TFET Biosensor

This study investigates the performance and simulation of a gallium arsenide (GaAs) Pocket-Hetero-Vertical-Tunnel field-effect transistor (GaAs-hetero-V-TFET) with a nanocavity for potential biosensing applications. The primary goal of this paper is comparing the various parameters for a few biomolecules including APTES (3-aminopropyltriethoxysilane), keratin, staphylococcal nuclease, and gelatin with varying dielectric constant values. The biomolecules with distinct dielectric constants are positioned inside the nanocavity near the sides of the channel of the device structure, which allows for the observation of the changes of the drain current versus gate voltage characteristic graph. Substantially improving the output characteristics of the proposed V-TFET, the dual metal work function designs improve the sensitivity of the GaAs-hetero-V-TFET biosensor. By incorporating distinct biomolecules, several electrical metrics, including drain current, electric field, threshold voltage, electron band-to-band tunneling rate, and drain current sensitivity, changed significantly. With an excellent subthreshold swing (14.45 mV/dec), the biosensor can detect a maximum ON-current of 6.64 × 10⁻⁵ A/µm and an OFF-current of 2.36 × 10⁻¹⁸ A/µm for the gelatin at κ = 12. The biosensor's sensitivity of κ = 12 has been determined by studying both neutral and charged biomolecules. The provided biosensor explored the transconductance sensitivity at 9.43 × 10⁵ and the drain current sensitivity at 2.61 × 10⁶. Finally, compared to earlier reported investigations, it has been demonstrated that the presented biosensor device produces superior sensitivity.