Ferroelectric charge-plasma DGDP-JLTFET biosensor with H-shaped nanocavity for ultra-selective cancer and virus detection

Abstract This research introduces a novel ferroelectric (FE) N + pocket-doped double-gate–drain-pocket tunnel field-effect transistor (TFET) biosensor, built on a junction less TFET (JLTFET) using the charge plasma technique for simplified, cost-effective fabrication and reduced random dopant fluctuation. The triple-gate structure has heavily N-doped drain, and a unique T-shaped channel with H-shaped cavities in a triple heterojunction (Si/SiO 2 /HfO 2 /Si:HfO 2 ) for enhanced sensitivity. Fabricated with Si, SiO 2 , HfO 2 , and ferroelectric Si:HfO 2 , the device detects biomolecules—including SARS-CoV-2, carbohydrates, RNA, amino acids, and breast cancer cells—via cavities at the gate-source and gate-drain junctions formed by sacrificial etching. Calibrated 2D simulations studied cavity size, temperature, and occupancy effects, showing higher dielectric constants increase drain current and detection capability and show strong tolerance to external noise and charge instability. Optimized dimensions achieved exceptional sensitivity 7.4 × 10 11 for neutral, 8.35 × 10 12 for positively charged, and 7.30 × 10 11 for negatively charged biomolecules for breast cancer cells, surpassing advanced biosensors in selectivity and performance, highlighting their strong potential for broad biomolecular detection applications.