Investigation of Electrical Characteristics of a SiGe Multi-Channel Junctionless Nanowire FET at the Sub-5 nm Technology Node

As semiconductor technology advances toward the sub-5 nm regime, maintaining high device performance while suppressing short-channel effects, leakage current, threshold-voltage instability, and power dissipation has become increasingly challenging. Thus, the design and analysis of new silicon-germanium (SiGe) based Multi-Channel Junctionless Nanowire Field Effect Transistor (MC-JL-NWFET) are discussed in this paper to enhance performance of such devices. The proposed device includes two stacked channels made from nanowires controlled by several gates, which makes it possible to improve electrostatic control and enlarge conduction area. Realistic results concerning the properties of the proposed device were obtained considering the effects such as Fermi-Dirac statistics, bandgap narrowing, electron mobility decrease, self-heating and quantum confinement. It was found out that the device demonstrates excellent behavior characterized by high level of transfer and output characteristics, reliable operation because of good electrostatic properties, high level of drive current and prevention of short-channel effect. Device scaling allows stating that 5 nm MC-JL-NWFET has 181.8 % improvement in transconductance, 78.6 % increase in ON-state current comparing with 120 nm one. Also, it is necessary to note that the changes in threshold voltage due to reduction in gate length are relatively small (only 18.8 %). All these results are achieved owing to high electron mobility of SiGe materials and better electrostatic control.