Performance investigation of steep-slope core–shell nanotube indium nitride electron–hole bilayer tunnel field effect transistor

Abstract

In this paper, the effects of main physical and structural parameters on the electrical characteristics of indium nitride core–shell nanotube electron–hole bilayer tunnel field effect transistor (NEHBTFET) are comprehensively investigated via simulation study for optimizing the device performance. The proposed structure offers excellent band to band tunneling efficiency and steeper turn-on drain current by providing the tunneling junction normal to the gate electric field between the region of outer shell gate and inner core gate. The simulation results reveal that the on-state current and subthreshold swing of NEHBTFET are greatly improved via expanding the band to band tunneling area along the channel and in the vertical direction in comparison with conventional nanowire TFET with narrow lateral source–channel tunneling junction. The n+–p+ tunneling junction is created electrically in the intrinsic region and a framework of core and shell gate work function engineering are conducted via calculating 2D variation matrix of the on-state current and threshold voltage for optimizing the device performance. The sensitivity of device’s main electrical parameters with respect to the variation of device physical and geometrical parameters reveals that the electrical parameters are highly insensitive to the source doping density which solves the major challenge of low solubility of dopants in III-nitride devices. In addition, the off-state current and subthreshold swings are not affected by the gate length scaling that is an indication of feasibility of this device in nanoscale regime.