DC and RF/analog performances of dielectric-modulated split-source double gate TFET biosensor: A simulation study

This work presents split source double gate (SSDG) dielectric modulated (DM) TFET for label free biosensing. The nanogap cavity is considered near the source region to lodge an enormous amount of biological molecules. In SSDG-DMTFET the source is split in two separate sections. The lower half is formed out of Germanium, whereas the upper part is comprised of Silicon. Reduced current leakage, improved inclination with respect to SS, and decreased ambipolar conductance are the results of these hetero-structural modifications. The use of a dual metal gate (DMG) in combination with the split source architecture significantly enhances the electrostatic control over the channel, which leads to further performance improvements. It also provides a comparatively improvement in current sensitivity and SS due to its enhanced tunneling area. The performance is evaluated for fully and partially filled nanogap with wide variation in dielectric constant (k). We have reported the SS, input characteristics, output characteristics, energy band diagram, (VTH) and ION/IOFF ratio by varying k from 1 to 12. Furthermore, sensitivity of SSDG-DMTFET is compared with the sensitivity of existing FET/TFET based biosensors.