A Spectroscopic Differential Reflectometry Study of (100), (110), (111), (311), and (511) Silicon Surfaces

Spectroscopic Differential Reflectometry, SDR, has been applied to study differences in silicon surfaces with different crystallographic orientations and with very thin films. The SDR technique measures the normalized difference in reflectance of two adjacent samples in the spectral range of 250-800 nm at near normal incidence. This study demonstrates the surface sensitivity of the SDR technique to the Si crystal orientations, and to the presence of thin oxide films on the Si substrate. The observed orientation dependent spectral features are interpreted in terms of the current understanding of the silicon orientation dependent oxidation kinetics