X-ray luminescence of disperse SiO2 and porous silicon

We carry out a comparison between the luminescence spectra (photo-and x-ray luminescence) of porous silicon and disperse SiO2, which by its physical characteristics is most similar to oxide films on porous silicon. The photoluminescence of porous silicon was also investigated using fluorescence (excitation by a nitrogen laser) and metallographic microscopes. We found that the natures of the luminescence centers of porous silicon and disperse SiO2 are identical. A porous layer on single-crystal silicon ensures the creation of a highly branched surface of oxide film. Luminescence centers are located on its inner (as viewed from the porous silicon) surface.