Diagonal Tunneling TFET with Dielectric Modulation: Design Optimization and Sensing Performance Investigation
摘要
In this paper, a novel Diagonal Tunneling DMTFET (DT-DMTFET) biosensor is proposed and simulated for high sensitivity biomolecule detection with improved electrical and sensing performance. The proposed device uses scaling optimization, triple source-pocket engineering and a high-K TiO2 gate dielectric to increase diagonal band-to-band tunneling and carrier transport efficiency. The proposed DT-DMTFET is compared to lateral tunneling (LT-DMTFET) and vertical tunneling (VT-DMTFET) structures and the DT-DMTFET has superior sensing and electrical properties due to improved tunneling behavior and optimized device structure. The proposed device performance has been evaluated in Silvaco ATLAS TCAD in terms of performance parameters Ion, Ioff, Ion/Ioff ratio and sensitivity. The proposed DT-DMTFET achieves an Ion of 5.41 × 10–11 and an Ion/Ioff ratio of 1.05 × 106 confirming its suitability for biosensing applications. The device can detect neutral, positive and negative charged biomolecules placed into the biosensor cavity. Furthermore, the effect of various cavity filling factors ranging from 25 to 100% is investigated, with the device demonstrating superior current response and sensitivity at 100% cavity filling. The effect of varied temperature conditions is also explored and the proposed DT-DMTFET has stable sensing behaviour and better responsiveness at different temperatures. The obtained results show that the proposed DT-DMTFET biosensor has increased sensitivity and electrical performance making it a suitable contender for future low-power, high sensitivity biomedical sensing applications.