A systematic study was made of the dependence of the photoluminescence, from porous material, upon the extent of oxidation and the measurement temperature. The oxidation of porous samples, at between room temperature and 200C, led to the appearance of photoluminescence spectra with maxima that were centered around 1.7eV. These maxima shifted, as a function of temperatures of between 10 and 300K, and always tended towards the 1.7eV position. The results disagreed with the predictions of the quantum confinement model for luminescence from porous material, but could be explained by assuming that several types of luminescence center outside of nano-scale Si units in porous material were responsible for the luminescence. The relative contributions to the luminescence changed with the extent of oxidation and the measurement temperature.

G.G.Qin, H.Z.Song, B.R.Zhang, J.Lin, J.Q.Duan, G.Q.Yao: Physical Review B, 1996, 54[4], 2548-55