High-pressure studies of photoluminescence in porous silicon

Raman scattering and photoluminescence measurements performed on porous sil icon at high hydrostatic pressures up to 21 GPa indicate that the phase-tra nsition pressure in this material is porosity dependent and much higher tha n in bulk crystalline silicon. For porosities higher than 80% the phase tra nsition occurs at 18 GPa followed by unrecoverable suppression of both Rama n and luminescence activity. The obtained results are consistent with the q uantum-confinement model. [S0163-1829(98)02745-3].