The structure of nanometer-sized strained Ge islands epitaxially grown on a Si substrate was studied using ultrasonic force microscopy (UFM), which combines the sensitivity to elastic structure of acoustic microscopy with the nanoscale spatial resolution of atomic force microscopy. UFM not only images the local surface elasticity variations between the Ge dots and the substrate with a spatial resolution of about 5 nm, but is also capable of detecting the strain variation across the dot, via the modification of the local stiffness. [S0031-9007(98)06741-6]

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The transport of ion-implanted F in amorphous Si is studied using secondary ion mass spectroscopy and transmission electron microscopy. Significant redistribution of F is observed at temperatures in the range 600–700 °C. The measured F depth profiles are modeled using a simple Gaussian solution to the diffusion equation, and the diffusion coefficient is deduced at each temperature. An activation energy of 2.2 eV±0.4 eV for F transport is extracted from an Arrhenius plot of the diffusion coefficients. It is shown that the F transport is influenced by implantation-induced defects.

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The characteristics of the formation and growth of buried oxide layers, formed by oxygen implantation into silicon at lower energies (50–140-keV 16O+), have been studied using secondary-ion mass spectrometry. Some results have been checked and compared with the results obtained by Rutherford backscattering and cross-sectional transmission electron microscopy. The critical doses, required to form a continuous buried stoichiometric oxide layer during implantation (ΦIc) and after annealing (ΦAc) have been estimated from experimental results. The thicknesses of the silicon overlayer (TASi) and buried silicon dioxide layer (TASiO2) for the annealed wafers have also been estimated. A set of semi-empirical formulas for ΦIc, ΦAc, TASi, and TASiO2 has been introduced. These formulas can be used to quickly calculate the critical doses and the layer thickness values.