A Novel Extended Source TFET with δp+- SiGe Layer

Abstract

Tunnel FET (TFET) is a significant discovery in the field of low power application, which has the ability to sustain short channel effects arising due to scaling. But the disadvantage of TFET is low ON current, and it is a challenge to maintain a high ON current with very low OFF current, hence it is tough to obtain a higher switching ratio maintaining a low SS. In this paper, to investigate the influence of dimensionality and other electrical parameters on TFET with simulation, a device based on an extended source TFET (ES-TFET) with SiGe pocket layer at the edge of source channel junction is proposed. It shows excellent performance improvement over standard TFET. In this paper, for the first time the effect of increase in length of the extended source has been studied while SS degrades but threshold voltage remains unchanged, also extended source distance from surface degraded effect on SS has been improved with the introduction of SiGe layer. Various scaling parameters have been investigated to study its impact on electrical parameters showing an ON-current of 0.01 mA/μm and OFF-current of 6.48 × 10−17 A/μm neglecting gate leakage for 1 V gate and drain voltage. The Remarkable value of SS of 16 mV/decade and ON-OFF current ratio of more than 1011 for a threshold voltage of 0.4 V is obtained. Scalability of the proposed device according to ITRS is well maintained, and it is validated by its improved performance over the wide range of channel length.