Impact of the Figures of Merit (FoMs) Definitions on the Variability in Nanowire TFET: NEGF Simulation Study

In this article, we investigate the effect of variability in p-type nanowire tunnel FET (TFET) using quantum mechanical transport simulations. The simulations have been carried out using the Nano Electronics Simulation Software (NESS) from the University of Glasgow. Random discrete dopants (RDDs) and work-function variations (WFV) have been investigated in the simulations. Our statistical simulations reveal that key figures of merit (FoMs) such as the current variability generally decrease as the gate voltage decreases, the threshold voltage variability increases as the threshold current increases, and the dependences of these FoM variabilities on criteria become stronger with the switch characteristic ameliorated. Furthermore, it is interesting to find that the band offset in heterostructure can more or less alleviate the current variability, especially around the OFF-state.