Ultra high vacuum growth of CrSi2 and [formula omitted] nanoislands and Si top layers on the plasma modified monocrystalline silicon surfaces

Abstract

A set of silicon substrates processed by compression plasma was studied by means of atomic force microscopy (AFM). AFM data revealed a threshold nature (in terms of plasma flow energy) of the formation of tube-like surface structures (SS) observed as “waves” regardless of the conductivity type, resistivity, and the substrate orientation ((111) or (100)). For the first time nanoheterostructures Si(111)/NC CrSi2/Si and Si(100)/NC β-FeSi2/Si have been formed on silicon substrates processed by compression plasma flow. Avery high density of CrSi2 nanoislands — (2–3)×1011 cm−2 was obtained for Cr–Si system but in the case of Fe–Si system the β-FeSi2 nanoislands density was only about 2×109 cm−2. According to the optical spectroscopy data during the process of silicon capping layer formation the CrSi2 and β-FeSi2 nanocrystals move up to the surface.