Improving On-state current and Ambipolarity of TFET using Gate-Drain and Gate Dielectric Engineering

This article presents the Gate Overlap on Drain with Hetero Gate Dielectric TFET (GDHD-TFET), a novel tunnel FET structure aimed at addressing the low ON current and ambipolar leakage observed in traditional TFETs. By investigating the combined effects of hetero gate dielectric and gate-drain overlapping, the GDHD-TFET offers a significant improvement in design compared with conventional TFET design. Unlike traditional approaches that focus solely on regulating the tunnel barrier widths at the channel-source junction, the GDHD-TFET simultaneously improves the tunnel barrier widths at both channel-source and channel-drain junctions. As a result, the GDHD-TFET achieves remarkable improvements in ON current and ambipolar conduction, surpassing traditional TFET performance by factors of 10² and 10⁴, respectively. Furthermore, it maintains low subthreshold swing (SS) of 29.3 mV/dec indicating its potential for low-power applications.