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SiGeO films were deposited by LPCVD using Si2H6, GeH4 and O2 as reactive gases and furnace annealed to segregate the excess of Ge in the form of nanocrystals embedded in a SiO2 matrix in a low temp. budget process fully compatible with current processing technologies. For low GeH4 partial pressures (4.8 mTorr) and a deposition temp. of 450 C, the deposited film consists of a SiO2 matrix incorporating Ge atoms, and no Ge oxides are detected. After annealing of the sample at a temp. of 600 C, quasi-spherical isolated Ge nanocrystals homogeneously distributed throughout the whole film thickness, with diams. ranging from 4.5 to 9 nm and an areal d. of around 7 1011 cm-2, are formed while the SiO2 matrix holds its original compn. Increasing the GeH4 partial pressure results in only a slight increase in the d. of nanoparticles with no significant changes in their diams. and a matrix is formed by a mixt. of Si and Ge oxides. A decrease in the deposition temp. results in very slow growth rates. Finally, increasing the annealing temp. causes no improvement in the sample characteristics, but a transformation of the matrix into a mixt. of Si and Ge oxides takes place and Ge diffusion processes start to appear. on SciFinder(R).