BRILLOUIN-SCATTERING FROM SHEAR HORIZONTAL SURFACE PHONONS IN BURIED SIO2 LAYERS

Experimental evidence and a theoretical explanation of Brillouin scattering from shear horizontal surface acoustic phonons in an Si buffer with a buried SiO2 layer are given in both the discrete and continuum parts of the spectrum. This is the first experimental observation of Brillouin scattering from shear horizontal acoustic phonons in the continuum spectral region. The intensity and position of peaks in Brillouin spectra have been qualitatively described in terms of the layer projected phonon density of states calculated for such a structure.