The float zone (high-resistance) silicon irradiated with swift heavy ions was studied by photoluminescence (PL) spectroscopy method. In addition to well-known X, W, W’, R and C lines, a broad peak (1.3 – 1.5 μm) appears in PL spectra at low-temperatures. As the irradiation dose increases from 3•10_11 to 10_13 cm-2, the PL intensity decreases by about an order of magnitude, also a narrowing of the peak with red-shift is observed.

Films of nonstoichiometric germanosilicate glasses GeO0.5[SiO2]0.5 and GeO0.5[SiO]0.5 were obtained by co-evaporation of GeO2 and SiO2 or GeO2 and SiO powders, respectively, and by deposition on cold Si (100) and fused quartz substrates in a high vacuum. Then the films were annealed at temperatures up to 900 oC. The presence and phase composition of germanium nanoclusters in the films was investigated using Raman spectroscopy technique. The transformation after annealing of the GeSixOy matrix surrounding the nanoclusters was investigated using Fourier transform infrared spectroscopy. Analysis of the Raman spectra showed that annealing at a temperature of 800 oC led to the formation of germanium nanocrystals (NC-Ge), but the content of the amorphous germanium phase remains up to half of the volume. Annealing at a temperature of 900 oC led to almost complete crystallization of amorphous nanoclusters in all films. The sizes of the NC-Ge depended on the annealing temperature, the composition of the films, and on the substrate; in this case, the formation of Ge-Si nanocrystals was not observed.