Performance Assessment of Ge-Source Double-Gate PNPN TFET Based Biosensor

In this article, the performance of a proposed Ge-source and pocket-based tunnel-field-effect transistor (Ge-PTFET) based dielectrically modulated label-free biosensors is investigated using numerical analysis for energy band, electric field, drain current, sensitivity, etc. The suggested device's performances are compared to those of a conventional silicon tunnel FET (Si-TFET) biosensor. Using device-level simulation, the sensing capability of both devices was investigated, considering neutral/uncharged and charged biomolecules separately in the bio cavity. In Ge-PTFET, the use of low bandgap material Ge (0.66 eV) at the source and the counter-doped pocket at the source side tunneling junction make the barrier-width narrower, thereby increasing the tunneling possibility hence the on-current. As a result, the Ge-PTFET outperforms a Si-TFET-based biosensor in terms of sensitivity to two separate effects (dielectric constant and biomolecule charge density), making Ge-PTFET an attractive alternative design for FET-based sensor applications. SENTAURUS TCAD 2D device simulator was utilized to implement the suggested device and to run all the simulations.