A study on lightly-doped Cylindrical surrounding-gate 6H-SiC nanowire FET

摘要

The device characteristics of Cylindrical surrounding-gate (CSG) 6H-SiC NW FET is investigated in this paper. The results indicate that the surface potential, threshold voltage and the electric characteristics (transfer characteristics and output characteristics) is very sensitive to 6H-SiC nanowire radius, channel length, oxide thickness and temperature. The temperature dependence of CSG 6H-SiC NW FET is also discussed in this paper. When the nanowire radius is decreased, the minimum potential is lowered, the locations of minimum potential moves to the source side and the threshold voltage is increased. When the oxide thickness is increased, the locations of minimum potentials are not changed, but the minimum potentials themselves become larger and the threshold voltage become smaller. The minimum potential increases as the gate length decreases, but the threshold voltage decreased as the gate length decreases. With increasing temperature, the surface potential decreases and the location of minimum potential moves to the source side. The threshold voltage decreases monotonically with temperature. At strong inversion region, the drain current decrease as nanowire radius decreases, but increases as temperature decreases.