Regulated Dynamics with Two Monolayer Steps in Vapor–Solid–Solid Growth of Nanowires

The growth of ZnTe nanowires and ZnTe–CdTe nanowire heterostructures is studied by in situ transmission electron microscopy. We describe the shape and the change of shape of the solid gold nanoparticle during vapor–solid–solid growth. We show the balance between one monolayer and two monolayer steps, which characterizes the vapor–liquid–solid and vapor–solid–solid growth modes of ZnTe. We discuss the likely role of the mismatch strain and lattice coincidence between gold and ZnTe on the predominance of two monolayer steps during vapor–solid–solid growth and on the subsequent self-regulation of the step dynamics. Finally, the formation of an interface between CdTe and ZnTe is described.