An extensive analysis of source engineered tunnel FET for low power biosensing application

Abstract

In this work, the source-engineered tunnel field effect transistor is studied and optimized for low-power applications. To achieve this, a double-gate TFET structure is employed with extended-source. Further, the gate on source underlap (DG-TFET-ES_UDL) and gate on source overlap (DG-TFET-ES_OVL) are analyzed, but to decrease the ambipolar current, a dielectric pocket near the channel and drain junction is assessed. To observe the electrical characteristics of the proposed device, the drain current versus gate voltage characteristic (transfer characteristic), energy band diagram, which provides valuable information about the charge distribution and energy levels within the device, subthreshold slope, electric field, and other parameters of the source engineered TFET with different device level techniques are explored. Furthermore, the tunneling device is utilized as a FET-based dielectric-modulated biosensor to understand the behaviour of the device when exposed to different biomolecules in a low-power scenario. Moreover, the study investigates the variation in drain current in response to changes in the dielectric constant of the biomolecules. This analysis helps in understanding the sensitivity of the device to different biomolecules and provides insights into its potential applications in biosensing. Silvaco Atlas TCAD, a widely used simulation tool, is employed to conduct comprehensive simulations.