Detection of Biomolecules Using Charge-Plasma Based Gate Underlap Dielectric Modulated Dopingless TFET

Abstract

In this Paper, Dielectric Modulated Dopingless Double Gate Transistor (DM-DLDGTFET) device is proposed for the free label detection of the charged and neutral biomolecules. A charge-plasma principle is used for label-free detection of biosensors to reduce the processing complexity and cost of nanoscale products. Firstly, the simulations for the proposed device are carried using Atlas and different electrical parameters are analyzed using the same. It is observed that the dielectric constant and different biomolecule charges for example, protein, DNA, enzyme, cell and many more molecules affects the electrical characteristic of the device. The deposition of different workfunction materials over silicon body will do the formation of p+ source and n+ drain region in the DM-DLDGTFET. In addition, by etching the segment of the gate oxide layer to the source end for sensing biomolecules, a nano gap cavity is embedded within the dielectric gate. When biomolecule get immobilized at cavity region, the electrostatic properties of device for example, drain current, Ion/Ioff, subthreshold slope, average subthreshold slope, sensitivity get influenced. The energy band diagram and the device’s surface potential for both neutral and charged biomolecules are also discussed. For the validation of the proposed DL-TFET structure, the simulation results are calibrated with reported results and significant improvement are observed in the proposed structure.