Design and Simulation of A Dielectric-Modulated TFET based Biosensor Using Extended Source Configuration

The study investigates the use of a single gate (SG) extended source Tunnel FET (ESTFET) for biosensing application. The suggested biosensor increases the capture area by adding nano-cavities close to the source region and utilizing the dielectric modulation approach. For SG-ESTFET based biosensors, the biosensing performance characteristics are determined, which include Charge Concentration fluctuation, ON-OFF Current Ratio Sensitivity (ION/IOFF), and Threshold Voltage Sensitivity (Vth). The experiment described in this paper was conducted using the Sentaurus TCAD simulator. Biomolecules that are negatively, positively, and neutrally charged are analyzed for a range of dielectric constants at the biomolecule equivalent insulator interface and the immobilization layer. To incorporate the real-time scenario, a thorough analysis of a partially filled nano-cavity produced by steric hindrance has also been supplied. Several instances of nano-cavities that are only partially filled have been taken into consideration in order to examine the sensitivity characteristics. Due to the influence of the back gate on the nano-cavity on the source side, it has been found that SG-ESTFET-based label-free biosensors are able to function. A number of significant biosensing characteristics are expected to have the following values for SG-ESTFET: 60 mV for threshold voltage sensitivity, 0.10346e11 for ON-OFF current ratio, and 32.04041e4 for ON-OFF sensitivity, respectively. These values are used to determine the sensitivity of the transistor. Lastly, in order to demonstrate the high sensitivity of our proposed biosensors, several sensitivity characteristics of SG-ESTFET are evaluated in comparison to the sensitivities of different biosensors that are considered to be state of the art.