Ultra-violet (UV), low penetration depth, micro-Raman spectroscopy and high resolution X-ray diffraction (HRXRD) are utilised as complementary, independent stress characterisation tools for a range of strained Si samples doped by low energy (2 keV) Sb ion implantation. Following dopant implantation good agreement is found between the magnitudes of strain measured by the two techniques. However, following dopant activation by annealing, strain relaxation is detected by HRXRD but not by micro-Raman. This discrepancy mainly arises from an anomalous red shift in the Si Raman peak position originating from the high levels of doping achieved in the samples. This has serious implications for the use of micro-Raman spectroscopy for strain characterisation of highly doped strained Si complementary metal-oxide semiconductor devices and structures therein. We find a direct correlation between the Si Raman shift and peak carrier concentration measured by the differential Hall technique, which indicates that UV micro-Raman may become a useful tool for non-destructive dopant characterisation for ultra-shallow junctions in these Si-based materials.
Item Type:
Article (Published)
Refereed:
Yes
Uncontrolled Keywords:
Raman; strained silicon; annealing; antimony; carrier density; elemental semiconductors; Hall effect; ion implantation; Raman spectra; red shift; semiconductor doping; silicon; stress relaxation;
Copyright 2008 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
Funders:
Science Foundation Ireland
ID Code:
4710
Deposited On:
20 Jul 2009 12:59 by
Lisa O'Reilly
. Last Modified 16 Jan 2019 13:42