SOFT-X-RAY EMISSION OF POROUS SILICON NANOSTRUCTURES

The electronic structure of Si nanostructures in porous Si and purpose ly oxidized porous Si is investigated using soft x-ray emission spectr oscopy. Significant changes as compared to bulk Si ate observed. We in terpret the spectral changes as due to an altered electronic structure in the Si nanostructures. By imposing standing wave boundary conditio ns to the valence band wavefunctions we calculate the emission spectru m for thin Si sheets, in good agreement with the experimental spectra.