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A deep level transient spectroscopy (DLTS) study of electrically active defects in gamma-irradiated, n-type, Czochralski-grown silicon samples at different temperatures has been performed. It is shown that upon irradiation at low temperatures the migration of primary defects is very limited, resulting in formation of only VO centers. At higher temperatures these centers continue to form but the profile of the peak suggests that complex clustering of primary defects around VO centers occurs, contributing to the stress in material. After irradiation at higher temperatures a vacancies become more mobile contributing to the formation of multivacancy-related defects. Besides formation of divacancies, a deep level at Ec – 0.32 eV has been detected in DLTS spectra. This level is identified as divacancy-oxygen V2O complex.

We present a preliminary study of Ge islands formation on Si(100) substrates using grazing-incidence small-angle X-ray scattering (GISAXS). Samples were prepared by a high-vacuum evaporation of a 5nm thick Ge layer on Si(100) substrate held at 200  C. The samples were subsequently annealed at different temperatures for 1h in vacuum, yielding to island formation. A Fortran program IsGISAXS was used for the simulation and analysis of Ge islands. Vertical cut (perpendicular to the surface) of the experimental 2D GISAXS pattern has been fitted using a Guinier approximation. Obtained parameters were used for the simulations. The simulated 2D GISAXS pattern well reproduce experimental data for cylindrically shaped islands with morphological parameters R=4 nm, H/R= 0.25 and the average inter-island distance D=5 nm.