Atomistic simulation of stone-wales defect position in armchair graphene nanoribbon field-effect transistor

Graphene continues to fascinate the research community due to its excellent physical and electrical properties. In this study, the electronic and transport characteristics of armchair graphene nanoribbon (AGNR) with a Stone-Wales (SW) defect is investigated. The SW defects are located at three different locations on the AGNR device; underneath the metal gate, near the drain and near the source. The band structures, density of states and transmission spectra are analyzed. The current-voltage characteristics are then extracted and the performance of pristine AGNR and AGNR incorporated with the SW defects is analyzed. From the simulation, it is found that the SW defect alters the electronic and transport properties of the AGNR. Remarkably, the SW defect increases the amount of energy bandgap, while decreasing the drain current. Most notable, the drain current of AGNR FET with SW defect near its source had decreased by almost 60 % compared to the perfect AGNR FET, while the defect at the center caused the drain current to decrease by only 4.13 %. The outcome of this study suggests that defects present on AGNR are not unreasonable and may be useful to enhance the transport properties of AGNR FET. The position of SW defect on the AGNR conducting channel plays an important role to enhance the electrical characteristics of the AGNR FET.