Natural occurrence of the diamond hexagonal structure in silicon nanowires grown by a plasma-assisted vapour-liquid-solid method.

Silicon nanowires have been grown by a plasma-assisted vapour-liquid-solid method using tin as the catalyst. Transmission electron microscopy in the [12[combining macron]10] zone axis shows that the diamond hexagonal (P63 /mmc) crystal structure is present in several nanowires. This is the first unambiguous proof of the natural occurrence of this metastable phase to our knowledge.