Sensitivity Analysis of Junction Free Electrostatically Doped Tunnel-FET Based Biosensor

Abstract

The electrostatic doping technique has the ability to reduce random dopant fluctuations (RDFs), fabrication complexity and high thermal budget requirement in the fabrication process of nano-scale devices. In this paper, first time propose and simulate a Junction Free Electrostatically Doped Tunnel Field-Effect Transistor (JFED- TFET) based biosensor for label-free biosensing applications. The gate dielectric modulation concept used for sensing the existence of biomolecules inside the nano-cavity, created in gate dielectric material towards the tunneling junction to modulate the tunneling mechanism. The sensitivity of JF-ED-TFET biosensor investigate with various types of biomolecules based on dielectric constants (k) and charge densities (ρ). The sensing response of the JF-ED-TFET biosensor analyze in terms of electric field, energy band and transfer characteristic and the sensitivity in terms of ION, ION/IOFF ratio and Subtheshold Swing. The sensitivity of device investigated based on practical challenges as different filling factor and step-profile generated from the steric hinderance. The effect of temperate and nano-cavity dimensions variation on device performance also has been analyzed. In this work, various types of biomolecules as Streptavidin (k = 2.1), Ferro-cytochrome c (k = 4.7), keratin (k = 8) and Gelatin (k = 12) has been considered for the performance investigation.