Engineered Nanopores-Based Armchair Graphene Nanoribbon FET With Resonant Tunneling Performance

Abstract

This article presents a novel armchair graphene nanoribbon (AGNR) field-effect transistor with engineered nanopores for resonant tunneling. Two rectangular nanopores are punched to create two potential barriers and one quantum well. Channel and source and drain contacts are AGNR, indicating structure homogeneity. Nonequilibrium Green’s function and Poisson’s equations are used for structural analysis. The input variables are well width (WW), drain voltage ( ${V}_{D}{)}$ , and barrier width (BW). The effects of repositioning nanopores and AGNR type (i.e., semiconductor and semimetal) are also studied. The impact of the parameters on the density of states, transmission probabilities, peak current ( ${I}_{P}{)}$ and its voltage ( ${V}_{P}{)}$ , valley current ( ${I}_{V}$ ) and its voltage ( ${V}_{{V}}{)}$ , and peak-to-valley ratio (PVR) are investigated. Simulation results show that in both AGNR types, a decrease in WW brings about higher ${I}_{P}$ , ${V}_{P}$ , and ${V}_{V}$ . Moreover, in the semimetal AGNR, the narrowest WW leads to the highest PVR value. Another key observation is that with a decrease in ${V}_{D}$ , the PVR increases, and negative gate transconductance (NGT) characteristics show better performance. In addition, in the semimetal AGNR, the highest PVR value and the best NGT characteristics occur at the highest BW. Furthermore, repositioning nanopores across the device width does not affect the energy of the first resonance level. Finally, the structure with the largest unobstructed width (i.e., the one with the least backscattering) has the highest PVR.