MULTIPLE PEAK PHOTOLUMINESCENCE OF POROUS SILICON

The photoluminescence (PL) response of porous silicon is usually in th e form of a single broad peak. Recently, however, PL response with two peaks has been reported. Here we report the observation of multiple p eaks in the PL spectrum of porous silicon. A simple modeling of the li ne shape indicates that four peaks exist within the response curve, an d analysis suggests that the PL of porous silicon is derived from quan tum confinement in the silicon crystallites. The line shapes can be du e to either minibands within the conduction and valence bands or cryst allite size variation or a combination of the two.