Analysis of non-uniform hetero-gate-dielectric dual-material control gate TFET for suppressing ambipolar nature and improving radio-frequency performance**Project supported by the University Natural Science Research Key Project of Anhui Province, China (Grant No. KJ2017A502), the Introduced Talent Project of Anhui Science and Technology University, China (Grant No. DQYJ201603), the Excellent Talents Supporting Project of Colleges and Universities, China (Grant No. gxyq2018048), and

Abstract

A tunnel field-effect transistor (TFET) is proposed by combining various advantages together, such as non-uniform gate–oxide layer, hetero-gate-dielectric (HGD), and dual-material control-gate (DMCG) technology. The effects of the length of non-uniform gate–oxide layer and dual-material control-gate on the on-state, off-state, and ambipolar currents are investigated. In addition, radio-frequency performance is studied in terms of gain bandwidth product, cut-off frequency, transit time, and transconductance frequency product. Moreover, the length of non-uniform gate–oxide layer and dual-material control-gate are optimized to improve the on-off current ratio and radio-frequency performances as well as the suppression of ambipolar current. All results demonstrate that the proposed device not only suppresses ambipolar current but also improves radio-frequency performance compared with the conventional DMCG TFET, which makes the proposed device a better application prospect in the advanced integrated circuits.