Performance Metrics of Pristine Graphene Nanoribbons Field-Effect Transistor with Different Types of Contacts

Abstract

Graphene nanoribbons (GNRs) have drawn significant research interest due to its excellent electronic properties. Recent studies have been carried out developing graphene nanoribbons field-effect transistor (GNRFETs). In this research, a pristine 13-armchair GNRFETs (13-AGNRFETs) at 5 nm length of the channel with different types of contact is modelled via numerical real space nearest-neighbour tight-binding method. Two different types of contacts connected to the pristine 13-AGNRFETs are explored, namely semiconducting doped armchair GNRs and semimetallic zigzag GNRs. Band structure and localized density of state (DOS) of both types of contacts are shown. Effect of varying types of contacts on current transport properties of the pristine 13-AGNRFETs such as the current-voltage characteristics curve is examined. After that, the performance metrics of the simulated device, for instance, drain-induced barrier lowering (DIBL), subthreshold swing, current ratio, and threshold voltage, are computed. After analyzing and comparing the output, it is found that on-state current, off-state current, subthreshold swing, and DIBL for 13-AGNRFETs connected to semiconducting doped armchair GNRs contacts is lower than semi-metallic zigzag GNRs contact. In contrast, current ratio and threshold voltage for semiconducting doped armchair GNRs contacts are higher than semi-metallic zigzag GNRs contact. The device with doped armchair GNRs contact is less suffered from short channel effect and leakage current.