SiX₂ (X = S, Se) Nanowire Gate-All-Around MOSFETs for Sub-5 nm Applications

The gate-all-around (GAA) field-effect transistor (FET) holds great potential to support next-generation integrated circuits. Nanowires such as carbon nanotubes (CNTs) are one important category of channel materials in GAA FETs. Based on first-principles investigations, we propose that SiX₂ (X = S, Se) nanowires are promising channel materials that can significantly elevate the performance of GAA FETs. The sub-5 nm SiX₂ (X = S, Se) nanowire GAA FETs exhibit excellent ballistic transport properties that meet the requirements of the 2013 International Technology Roadmap for Semiconductors (ITRS). Compared to CNTs, they are also advantageous or at least comparable in terms of gate controllability, device dimensions, etc. Importantly, SiSe₂ GAA FETs show superb gate controllability due to the ultralow minimum subthreshold swing (SS_min) that breaks “Boltzmann’s tyranny”. Moreover, the energy-delay product (EDP) of SiX₂ GAA FETs is significantly lower than that of the CNT FETs. These features make SiX₂ nanowires ideal channel material in the sub-5 nm GAA FET devices.