Modeling and simulation of strained graprene nanoribbon field effect transistor

Abstract

Stretching technique used in material fundamental is not a new technology. It has been adopted in silicon industry to overcome the limitations arisen by scaling down the size of the conventional metal oxide semiconductor Field Effect Transistor (FET). This technique is known as strain technology. As the semiconductor industry grows in their maturity, the replacement of strained silicon with another material offering a higher potential quasi-ballistic-carrier velocity and higher mobility is importance. Recent enlisted superior material is quasi-one dimensional Graphene NanoRibbons (GNR). GNR is the most promising material for future nanoelectronic that inherited most properties from graphene and Carbon NanoTube (CNT) itself. To characterize the effect made by strain technology in silicon, an analytical model of strained GNRFET is presented in this work to analyse the suitability of this material for future FET. This works presents a simple model of current-voltage characteristic in the function of strain for different widths. By using a tight-binding approximation and analytical solution, the strained GNR bandstructure, density of states and carrier statistic are presented. Further observation on their carrier transport and their current-voltage characteristic is also investigated and presented in this research. It is found in this research that strain gives significant effect according to different width groups. It is successful in tailoring the energy gap and linearly changing the carrier statistic and carrier transport. In terms of physical and electrical performance, strained 3m+1 GNR is found to be a good material for future FET with enhanced mobility due to the energy gap alteration by strain. Strained GNRFET also was found to be 55mV/dec in subthreshold slope, which is smaller than normal GNRFET, which means the transistor has faster switching. Besides, the currentvoltage characteristic is reported to have delayed saturation region compared to published model due to the different in quantum effect consideration.