In situ TEM observation of the vapor–solid–solid growth of <00> InAs nanowires

In situ transmission electron microscopy characterization is a powerful method in investigating the growth mechanism of catalyst-induced semiconductor nanowires. By providing direct evidence on the crystal growth at the atomic level, a real-time in situ heating investigation was carried out on Au-catalyzed <00> InAs nanowires. It was found that the Au catalyst maintained itself in the solid form during the nanowire growth, and maintained a fixed epitaxial relationship with its underlying InAs nanowire, indicating the vapor–solid–solid mechanism. Importantly, the growth of <00> InAs nanowires through a layer-by-layer manner at the catalyst/nanowire interface is evident. This study provides direct insights into the vapor–solid–solid growth and clarified the growth mechanism of <00> III–V nanowires, which provides pathways in controlling the growth of <00> semiconductor nanowires.