Dielectric Modulated Negative Capacitance Heterojunction TFET as Biosensor: Proposal and Analysis

In this article, a label-free biosensor with a single cavity that uses a negative capacitance heterojunction charge-plasma-based tunnel FET (NC-HJ-CP-TFET) is presented and examined. To increase ON-state current, ferroelectric material (Si:HfO₂) has been added to a stack with a gate insulator and low energy bandgap material (Si_0.5Ge_0.5). In terms of biosensing properties, comparisons have been made between NC-HJ-CP-TFET and Si-based NC-CP-TFET. The different bio-analytes employed in this work are Streptavidin (κ = 2.1), APTES (κ = 3.57), Bacteriophage (κ = 6.3), Protein (κ = 8), and Gelatin (κ = 12). Benchmarking is done to compare prospective biosensors to literature that has already been reported. The maximum ON-state current sensitivity (S_ION), transconductance-based sensitivity (S_gm), I_ON/I_OFF, and subthreshold swing (SS) obtained are 2 × 10⁸, 4 × 10⁸, 2.3 × 10¹¹, and 17.9 mV/decade, respectively, for NC-HJ-CP-TFET with permittivity of κ = 12 with fully filled nanogap of neutral bio-analyte.