Polarized micro-Raman scattering characterization of Mg₂Si nanolayers in (001) Si matrix

Abstract

An orientational growth of the Mg 2 Si lattice relative to the Si lattice is considered assuming minimum mismatch of their lattice parameters. The Raman scattering cross-sections are calculated for the four possible orientations of the Mg 2 Si lattice positioned in this way. The integral intensity ratios for the F 2g mode of Mg 2 Si in different polarization configurations, obtained from the experimental spectra, are compared with the calculated ratios.It is found that the Mg 2 Si nanolayer's morphology is sensitive to the implantation energy, which determines both the peak Mg concentration in the initial implantation profile and its position in the sample depth. At a peak concentration of the order of the stoichiometric concentration, the layers are highly oriented. When the peak concentration is higher and the peak is placed closer to the surface, the layers are polycrystalline.

A simple phase transformation strategy for converting silicon nanowires into metal silicide nanowires: Magnesium silicide

“…2(h)) indicated the presence of a triply degenerate F 2g mode corresponding to Mg 2 Si at 258 cm −1 [31]. Another broad peak at 345 cm −1 corresponding to the Fröhlich-interactioninduced Raman-inactive longitudinal optical (LO) mode of Mg 2 Si was also observed in the spectra [32]. The peak at 432 cm −1 is expected to be the result of the interfacial stress arising from the boundaries between Mg 2 Si nanowires and the bulk silicon wafer [33].…”