Raman microstructural analysis of silicon-on-insulator formed by high dose oxygen ion implantation: As-implanted structures

Abstract

A microstructural analysis of silicon-on-insulator samples obtained by high dose oxygen ion implantation was performed by Raman scattering. The samples analyzed were obtained under different conditions thus leading to different concentrations of defects in the top Si layer. The samples were implanted with the surface covered with SiO 2 capping layers of different thicknesses. The spectra measured from the as-implanted samples were fitted to a correlation length model taking into account the possible presence of stress effects in the spectra. This allowed quantification of both disorder effects, which are determined by structural defects, and residual stress in the top Si layer before annealing. These data were correlated to the density of dislocations remaining in the layer after annealing. The analysis performed corroborates the existence of two mechanisms that generate defects in the top Si layer that are related to surface conditions during implantation and the proximity of the top Si/buried oxide layer interface to the surface before annealing. © 1997 American Institute of Physics. ͓S0021-8979͑97͒07120-X͔

Micro-Raman spectroscopy of the solid state: applications to semiconductors and thin films

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Characterization of Si Nanocrystals

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Raman scattering studies of ultrashallow Sb implants in strained Si

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“…Thus the phonon's spatial confinement results in a broadening of the Raman scattering features reflecting the uncertainty in its energy and a red shift of the Raman peak position occurs with increasing spatial confinement, as lower-energy bulk-like phonons are incorporated into the wavefunction describing the nominally zone-centre confined phonon. The model used by Macia et al [7] to study silicon-on-insulator samples obtained by high dose oxygen ion implantation is adapted by introducing the parameter x 0 , which represents the stress-induced Raman line shift. Assuming a constant correlation length L in the scattering volume, the intensity of the first order Raman band of silicon is given by…”