Characterization of nano-scale strained silicon-on-insulator substrates by multi-wavelength high resolution micro-raman and optical reflectance

Abstract

Strained silicon-on-insulator (sSOI) substrates were characterized using multi-wavelength, high resolution, polychromator-based micro Raman spectroscopy and normal incidence optical reflectance spectra measurement. Significant Raman shifts towards the lower wavenumber side, corresponding to tensile stress, and broadening of the Raman peak in sSOI thin films were observed. The stress and crystallinity of sSOI were characterized from the shift and full-width-at-half-maximum data. The thickness of strained Si and buried oxide film of sSOI was estimated from the optical reflectance. Multi-wavelength Raman and optical reflectance measurement, when used together provide a useful and practical non-destructive stress, and structural characterization technique for nano-scale sSOI.