Gate dielectric material dependence of current-voltage characteristics of ballistic Schottky barrier graphene nanoribbon field-effect transistor and carbon nanotube field-effect transistor for different channel lengths

Currently, the advancement of silicon transistor technology is being hindered by different issues such as scaling limits. It has become imperative to replace existing silicon technology with new technology to continue the scaling of MOSFETs. Thus, new materials and new production techniques are being studied laboriously to continue the trend set by Moore´s Law. The graphene nanoribbon (GNR) and the carbon nanotube (CNT) are two such promising materials that can replace silicon in future MOSFETs. A study has been conducted of the effect of the relative dielectric constant on the device performances of a ballistic Schottky barrier GNR field-effect transistor (GNRFET) and a CNT field-effect transistor (CNTFET) for two different channel lengths and a comparative analysis between the two transistors is provided. When a gate material with a high relative dielectric constant is used in FETs, it has been observed that both the transistors show higher on-state drain currents for the different channel lengths. Moreover, the on and off-state current ratios and transconductance for the GNRFET and the CNTFET are calculated and plotted for further differentiation between the performances of the GNRFET and the CNTFET.