Effect of the Si nanowire’s diameter and doping profile on the electrical characteristics of gate-all-around twin Si-nanowire field-effect transistors

The effect of the Si nanowire’s diameter and doping profile on the electrical characteristics of gate-all-around twin Si-nanowire field-effect transistors (TSNWFETs) was simulated by using the three-dimensional technology computer-aided design simulation tools of Sentaurus and taking into account quantum effects. While the switching and the short-channel immunity characteristics were improved with decreasing nanowire diameter, the threshold voltage and the total on-current for the TSNWFETs decreased, resulting in a deterioration of device performances. The swing characteristics for the TSNWFETs maintained almost the same behaviors regardless of the boron concentration variation in the nanowire. Gate-induced drain leakage (GIDL) of the TSNWFETs appeared at a high drain voltage, and the GIDL current increased with increasing boron concentration in the Si nanowires. The electrical characteristics of the TSNWFETs were improved by optimizing the diameter and the doping concentration of the Si nanowire to lower the GIDL and the off-state leakage current.