Impact of Underlap/Overlap on Source Engineered Tunnel FET

In this work the impact of overlap and underlap on double gate extended source tunnel FET (DG-TFET-ES) is analyzed. For this purpose, the transfer characteristics, energy band diagram and total current density of DG-TFET-ES simulated structure is compared with double gate tunnel field effect transistor-extended source overlap (DG-TFET - ES_OVL) and double-gate tunnel field effect transistor extended-source underlap (DG-TFET-ES_UDL) structures. The ATLAS simulator of SILVACO TCAD is utilized to perform all the device simulations. It is observed from the results that the ambipolar behavior of the TFET is improved when we are employing the underlap and overlap at channeldrain junction. Additionally, it has been found that the underlap structure has the narrowest tunneling barrier, making it the optimum choice for microwave applications.