It was demonstrated that flake-like structures containing Si-based nanosheets were successfully synthesized on Si(111) substrates. By exposure of CaSi 2 /Si substrates to CrCl 2 vapor, Ca atoms were extracted from CaSi 2 , then, the Si-based nanosheets were formed. The structural properties of the Si-based nanosheets formed at the edge of the flakes were examined. It is noted that the flake-like structures were rooted to the substrates, and that the Si-based nanosheets were easily exfoliated from the flake-like structures, to expose the surfaces corresponding to the Si{111} planes of the nanosheet, originated from the corrugated Si(111) layers linked by Ca in CaSi 2 .

The shape modification of Si nanowires is demonstrated using faceted solid silicide catalysts. The Si nanowires were grown on Si(111) substrates covered with Au as a catalyst using MnCl2 and Si powders as source materials. The solid silicide catalysts were nucleated and formed in the Au-Si catalyst solution at the top of the nanowires during the growth. The faceted solid silicides grew larger with increased growth time and played a role as a solid catalyst. The faceted shape of the catalyst defines the shape of the faceted Si nanowire. The squared Si nanowires were grown with the growth direction of Si[111] and the sidewalls of {110} and {211} planes. The growth evolution of the faceted Si nanowires occurs by a vapor-liquid-solid mechanism followed by the silicide vapor-solid-solid mechanism

Si nanowires were grown on Si(111) substrates, and the shape modification of the nanowires was demonstrated. With the Au catalyst, the highly symmetric faceted silicide solid particle in the Au‐Si eutectic solution was formed on the top of the nanowires, and the solid catalyst defined the shape of the Si nanowire. Namely, the VLS growth mechanism was followed by the VSS growth mechanism, and the modified shaped faceted Si nanowire was formed during the VSS growth. This result makes us to expect to control the shape of the nanowires by the formation of facetted silicide particles grown during the Au catalytic growth. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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