A Dielectric Modulated Polarity Controlled Electrically Doped Junctionless TFET Biosensor for IOT Applications

Abstract

In this manuscript, we investigate a new design of dielectric modulated polarity controlled electrically doped junctionless TFET (ED-JL-TFET) as highly receptive label-free biosensors. In the proposed structure, over the extensively doped n-type silicon substrate two electrode, gate electrode (GE) and source electrode (SE) are mounted having work function of 4.72 eV to alter the layer under GE and SE of intrinsic semiconductor. Further, for the formation of p${^+}$ region −1.2 V is applied at source electrode (SE). Therefore, the structure resembles n${^+}$-i-n${^+}$-p${^+}$ TFET. In addition to this, for the detection of biomolecule a nanogap cavity is setup in the gate oxide region near the source side. In this manuscript, the gate electrode of electrically doped junctionless TFET (ED-JL-TFET) is used to inflect the tunneling width for label free detection. Because of reduced fabrication challenges and cost effectiveness, ED-JL-TFET has been preferred as biosensor. Finally, the detection ability of ED-JL-TFET has been explored by varying charge density and dielectric constant of the biomolecule, height and length of the nanogap cavity region for different voltage condition by employing 2D Silvaco ATLAS TCAD device simulator.