“Structure and Photoluminescence Properties of Ge Nanocrystals in SiO2 Matrix Produced by Rf-Sputtering” A.G. Rolo, A. Chahboun, M. I. Vasilevskiy, M. J. M. Gomes “First International Workshop on Semiconductor Nanocrystals, SEMINANO2005”, Budapeste, Hungria, 10-12 de Setembro de 2005.