Monitoring of biaxial strained-silicon layers by spectroscopic ellipsometry

Spectroscopic ellipsometry (SE) has been extended to the non-destructive, in-line monitoring of biaxial tensile strain in strained silicon (epsiv-Si). SE data from 250nm - 500nm from three epsiv-Si samples were fitted using a new parametric model for semiconductors. By using the E1 peak shift in the fitted dielectric function spectra, the tensile strain in epsiv-Si can be monitored. Strain values obtained are in agreement with Raman measurements