3D atomic-scale insight into semiconductor nanowires

Semiconductor nanowires (NWs) are ideal to investigate the fundamental science of reduced dimensionality and size, and are also building blocks for devices in the proposed bottom-up paradigm. Controllable growth of NWs with desired properties and functionalities is the cornerstone to realize these applications. In this letter, we report that the reactant molecules impinged on the seed nanoparticles are responsible for the axial growth, and that the surface adatoms on NW sidewalls are responsible for radial deposition. There are also diffusion interactions between the core and shell at growth temperature. Our findings represent a significant advance to understand the NW growth mechanism, and are helpful to design and grow optimized NWs for applications.