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ZnS films deposited on Si, irradiated with Au ions and the sputtered particles, which are collected on catcher foils during irradiation, are analyzed using transmission electron microscopy. Coulomb explosion followed by thermal spike induced vaporization of ZnS is found to be the dominant mechanism regarding material removal at such high energy, where the evaporated material can cool down going into the fragmentation region forming clusters.

Nanocrystalline Sn particles have been formed in silica glass through 50 keV Sn- implantation followed by annealing in N2 at 650 °C for 30 min. Samples prepared this way have been annealed in air for 1 h, separately at four different temperatures, 400, 600, 800, and 1000 °C, each at a given temperature. Annealing at temperatures higher than 400 °C has been found to result in oxidation of the Sn nanoparticles (NPs) and formation of the SnO2 phase as confirmed from optical absorption (OA), transmission electron microscopy, and Raman scattering measurements. For the sample annealed at 600 °C, Raman scattering data showed three bands at about 525, 629, and 771 cm-1, the last two corresponding to the A1g and B2g classical Raman modes of rutile SnO2. Increase in annealing temperature resulted in an increase in the intensities of the A1g and B2g modes showing better crystallinity. Also, the A1g peak shifted toward a higher wave number with a steady decrease in the intensity at 525 cm-1. This is in line with the growth in size of NPs as well as a reduction in the surface disorder. The Urbach tail width derived from the OA data also agrees with this. [ABSTRACT FROM AUTHOR]

The formation and growth of various Sn[O.sub.2] nanoparticles in silica glass by using Sn implantation and annealing is explained. The analysis demonstrates that high annealing temperature leads to better crystallinity of the particles.