SPECTROSCOPIC ELLIPSOMETRY OF EPITAXIAL SI (100) SURFACES

The dielectric spectra of Si {111} and Si {100} orientations are shown to be equivalent using ex situ spectroscopic ellipsometry on clean epitaxial surfaces. The peak values for the real and imaginary parts (epsilon(r,i)) of the dielectric function exceed those previously reported, values of epsilon(i) (at 4.25 eV) greater-than-or-equal-to 47 being obtained. Surface features with lateral scales of almost-equal-to 0.5-2-mu-m, do not affect the dielectric spectra significantly. The high dielectric function peaks indicate that the nanometer lateral-scale roughness on these epitaxial surfaces is very small.