Enhanced RF analog linearity in metal gate modulated heterojunction based uniform TFET for label-free detection of dengue NS1 protein

• Published in: Scientific reports Vol. 15; no. 1; pp. 24026 - 24
• Main Authors: T, Ranjith Kumar, G, Lakshmi Priya
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 05.07.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 639/166/987; 639/301/1005/1007; 639/925/927; Accuracy; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensor; Biosensors; Dengue - diagnosis; Dengue - virology; Dengue fever; Dengue Virus; Dielectric cavities; Efficiency; Electrostatics; Engineering; Enzymes; Gain bandwidth product; Humanities and Social Sciences; Humans; Infectious diseases; multidisciplinary; NS1 protein; NS1 protein sensing; Plasma; Proteins; Science; Science (multidisciplinary); Sensitivity; Simulation; Spike protein; Transistors, Electronic; Uniform TFET; Vector-borne diseases; Viral Nonstructural Proteins - analysis; Dielectric cavities; Gain bandwidth product; Sensitivity; Uniform TFET; NS1 protein sensing; Biosensor
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-025-08892-5

This work presents a comprehensive investigation of symmetric (HJ-DD-UTFET) and asymmetric Source Drain Heterojunction Dual Dielectric Uniform Tunnel Field-Effect Transistors (A-SD-HJ-DD-UTFET) to achieve enhanced analog/RF, and linearity performance. The A-SD-HJ-DD-UTFET showcases an extremely low OFF current level of 8.124 × 10 –17 A/μm which surpasses the symmetric HJ-DD-UTFET by 5,470 times and presents a high ON–OFF ratio of 2.83 × 10 12 representing a 6,261 times improvement. This enhanced performance occurs because of structural asymmetry which makes it suitable for high-end RF and biosensing purposes while reaching a peak transconductance of 536 µS. For dengue NS1 protein detection (κ = 78.7), the TCAD-driven model of the proposed A-SD-HJ-DD-UTFET biosensor delivers a distinctive label-free detection method, achieving a peak transconductance (g m ) of 577 µS, cut-off frequency (f T ) of 193 GHz, Gain-Bandwidth Product (GBP) of 201 GHz, Transconductance Generation factor (TGF) of 155 V -1 , and gain transconductance frequency product (GTFP) of 25.9 THz. These correspond to improvements of 51.4%, 13.5%, 26.4%, 96.4%, and 45.5%, respectively, over SARS-CoV spike protein detection (κ = 2). The A-SD-HJ-DD-UTFET biosensor also exhibits superior linearity performance during dengue NS1 protein detection through its desirable intercept points, minimal intermodulation distortion, and a well-maintained 1 dB compression point, affirming its potential as a high-speed, label-free RF biosensor for infectious disease Point of Care Testing (POCT) diagnostics.