Sensitivity Analysis of Polarity Control Electrically doped GaAs-InAs Tunnel Field Effect Transistor for Bio-sensing Application

Abstract

In this paper, a novel III-V material-based polarity-controlled electrical doped Tunnel field effect transistor (PC- ED-GaAs-InAs-TFET) biosensor has been proposed. The N+ drain and P+ source regions are created in the intrinsic GaAs and InAs regions using the polarity-controlled concept. In addition, a nano-cavity is etched in the gate oxide towards the tunneling junction to modulate the tunneling mechanism via the immobilized biomolecules. The sensitivity of the proposed biosensor is analyzed using neutral and charged biomolecules, namely Biotin (k = 2.63), Ferro-cytochrome c (k = 4.7), Keratin (k = 8) and Gelatin (k = 12). The PC-ED-GaAs-InAs- TFET biosensor exhibits superior sensitivity in terms of drain current, threshold voltage, subthreshold swing, and $\mathrm{I}_{ON}/\mathrm{I}_{OFF}$ ratio. The sensitivity of the PC-ED-GaAs-InAs-TFET biosensor, in terms of various cavity dimensions (thickness and height), fill factors and the effect of temperature has also been investigated.