Performance of Sige Extended Source Pocket VTFET based Biosensor

Abstract

This work significantly advances dielectric-modulated biosensor performance through an innovative Extended Source Vertical TFET (ES-VTEFT) design. By integrating three key innovations—a SiGe P⁺ pocket for bandgap narrowing, an extended electrode overcoming material solubility constraints, and a 60-nm nano-cavity accommodating larger biomolecules (κ=1 to κ=12)—the device achieves substantial improvements over conventional VTFETs. The extended electrode's -1.2V bias sharpens interface abruptness by attracting holes from the Ge source, while the heterojunction-enhanced band modulation accelerates carrier transport. Performance metrics demonstrate a 100-fold drain current increase for neutral biomolecules (K=12), a 1000-fold enhancement for charged species, and 5 times higher sensitivity for k=12 biomolecules at Vgs = 0.9V. Crucially, the 50% reduction in transit time enables twice the sensing speed, establishing the ES-VTEFT as a high-sensitivity, rapid-response biosensing platform.