Symmetry forbidden Raman scattering from (100) surfaces of oxidized Si and Ge

Abstract

Raman scattering excited by light absorbed within 200 Å of the semiconductor surface has been used to characterize changes introduced at (100) surfaces of Si and Ge by oxidation. Oxidation dependent, broad band, first order Raman spectra similar in appearance to the spectra obtained from the amorphous phases of Si and Ge have been observed. These results are obtained for oxide thicknesses up to 1.7 μm without any special sample preparation, suggesting that Raman scattering can be a useful probe of such interfaces.