Vapor–Liquid–Solid Growth of Small- and Uniform-Diameter Silicon Nanowires at Low Temperature from Si₂H₆

Abstract

We report 350 °C as a critical growth temperature for overcoming the aggregation of gold (Au) in the synthesis of high-density silicon nanowires (SiNWs) with controlled diameters in a vapor–liquid–solid (VLS) mechanism by the low-temperature decomposition of Si2H6. Low-temperature growth is considered essential for preserving the initial distribution of Au droplets (8±5 nm) during SiNW nucleation with small (12 nm) and uniform (±5 nm) diameters. Au–Si eutectics increase in size with aggregation at high temperatures, resulting in SiNWs with large and random diameters. The crystal quality, defect formation, and morphology of the wires, grown in the (111) direction, are size dependent.