High-Frequency and Sensing Performance Optimization of Black Phosphorus Channel InSb/InGaAs TFETs: A Dual-Function RF Stability and Biosensing Perspective

The radio-frequency (RF) stability and performance improvement of InSb/InGaAs tunnel field-effect transistors (TFETs) integrated with a black phosphorus (BP) channel were thoroughly examined. The effect of critical RF parameters, such as the Stern stability factor (K) and critical frequency (fk), along with essential structural and material parameters including device geometry, high-κ dielectric integration, and applied bias conditions, is analyzed with respect to figures of merit such as gm (transconductance) and Cgg (gate capacitance) using 3D Silvaco Atlas TCAD simulations. An analytical framework is developed to relate fk to small-signal characteristics, offering precise design strategies for device optimization. Simulation results reveal substantial enhancements in ION current, transconductance, and cutoff frequency (ft), confirming the potential of the optimized BP-channel InSb/InGaAs TFET for high-frequency, energy-efficient analog, and RF applications. Additionally, the enhanced sensitivity, low power operation, and tunable bandgap of the BP channel position the device as a promising candidate for nanoscale sensing applications, such as biochemical detection and gas sensing, where high signal-to-noise ratio and real-time operation are critical. The optimized TFET achieves a critical frequency of 70 GHz, reinforcing its dual applicability in both RF electronics and high-performance sensing platforms.