A Charge-Plasma-Based Dielectric-Modulated Junctionless TFET for Biosensor Label-Free Detection

To reduce the fabrication complexity and cost of the nanoscale devices, a charge-plasma concept is introduced for the first time to implement a dielectric-modulated junctionless tunnel field-effect transistor (DM-JLTFET) for biosensor label-free detection. The formation of p+ source and n+ drain regions in DM-JLTFET is done by the deposition of platinum (work function = 5.93 eV) and hafnium (work function = 3.9 eV) materials, respectively, over the silicon body. Furthermore, a nanogap cavity embedded within the gate dielectric is created by etching the portion of gate oxide layer toward the source end for sensing biomolecules. For this, the sensing capability of DM-JLTFET has been investigated in terms of variation in dielectric constant, charge density, length, and thickness of the cavity at different bias conditions. Finally, a comparative study between DM-JLTFET and MOSFET biosensor is investigated. The implementation of proposed device and all the simulations have been performed by using ATLAS device simulator.