A Novel Symmetry L-shaped Source Vertical TFET with DC and RF Performance Analysis

A symmetry L-shaped source vertical tunneling field-effect transistor is proposed and investigated by using technology computer-aided design tools. Point and line tunneling are involved using L-shaped source. An optimal structure parameter of this device is given by comparing the on-state current, subthreshold voltage, and subthreshold swing. The electric field distribution, energy band profile and band-to-band tunneling rate distribution are analyzed to investigate the effect of an L-shaped source in a TFET. In addition, transfer characteristics, output characteristics, parasitic capacitance, transconductance and cut-off frequency of the proposed structure are analyzed and compared with the conventional structure. The simulation results reveal that the subthreshold swing of the symmetry L-shaped source device is 39.74 mV/dec and Ion/Ioff ratio is about 3.31 × 1012. The cut-off frequency of the proposed device is 40.82GHz with the gain bandwidth product of 12.88GHz. The proposed structure exhibits negligible drain-induced barrier lowering and ambipolar effects. The proposed device can improve the performance of subthreshold voltage and frequency characteristics than the conventional device.