Ambipolar CNTFET: Basic Characterization and Effect of High Dielectric Material

Recently, several emerging technologies have been reported for ambipolar devices. Ambipolar conduction is characterized by a superposition of electron and hole current. It has been experimentally reported in many technologies, including Carbon Nanotube Field Effect transistor (CNTFETs). In unipolar silicon CMOS devices p-type or n-type behavior is determined during fabrication. Whereas ambipolar devices behave either as p-type or n-type depending on gate bias conditions. In this paper, the effect of different dielectric materials used as gate insulator for Ambipolar CNTFET has been studied and simulated using Stanford H-spice model of CNTFET. Based on the simulation results l_d ~ V_d curves for ambipolar CNTFETs having different dielectric constants are plotted. For the same, l_d ~ V_g curves for different applied drain voltages are also plotted with fixed dielectric constants. Finally, the effect of different dielectric materials (K) are shown in K~l_d (Saturation current) plot.