Peculiarities of Raman spectra from porous silicon

The enhancement of the Raman intensity from a porous layer compared to the signal from the silicon substrate was observed. It is assumed that this phenomenon is due to the specific form of pores that leads to the optical effect of focusing of scattered light near the bottom of the macropores. It was shown that the peak position and shape of the Raman line depend on the nanostructure of the pore bottom.