Performance study of tunneling field effect transistors based on the graphene and phosphorene nanoribbons

The present work deals with the simulation and comparison of two tunneling field effect transistors (TFETs) based on the single layers of armchair graphene nanoribbons (AGNRs) and armchair phosphorene nanoribbons (APNRs). The transmission properties of the transistor have been obtained by solving the Schro??dinger-Poisson equations self-consistently using the nonequilibrium Green???s function (NEGF) formalism and the real-space approach. In addition, the energy band structure of the two materials have been obtained using tight-binding approximation method. The simulation results in each bias include the energy band structure, energy-resolved current spectrum, transmission function and drain current versus gate voltage diagrams. The results indicate that the structure of phosphorene TFETs meets a better ION to IOFF ratio and subthreshold swing than the graphene TFETs despite a relative decrease in the amount of ION.