Publications by authors named "L F Tz Kwakman"

A Ga focused ion beam (FIB) is often used in transmission electron microscopy (TEM) analysis sample preparation. In case of a crystalline Si sample, an amorphous near-surface layer is formed by the FIB process. In order to optimize the FIB recipe by minimizing the amorphization, it is important to predict the amorphous layer thickness from simulation.

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Recent improvements in a SEM-based X-ray tomography system are described. In this type of equipment, X-rays are generated through the interaction between a highly focused electron-beam and a geometrically confined anode target. Unwanted long-term drifts of the e-beam can lead to loss of X-ray flux or decrease of spatial resolution in images.

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This paper presents a new technique using energy filtered TEM (EFTEM) for inelastic electron scattering contrast imaging of Germanium distribution in Si-SiGe nanostructures. Comparing electron energy loss spectra (EELS) obtained in both SiGe and Si single crystals, we found a spectrum area strongly sensitive to the presence of Ge in the range [50-100 eV]. In this energy loss window, EELS spectrum shows a smooth steeply shaped background strongly depending on Ge concentration.

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The detectability of amplitude modulation and spatial frequency modulation of suprathreshold sine-wave gratings was measured at retinal eccentricities ranging from 0 to 30 deg. The main conclusions to be drawn from the experimental results are: (1) for this visual task it is not possible to bring peripheral sensitivity to the same level as foveal sensitivity by scaling the stimuli with the inverse of the cortical magnification factor M. (2) Increasing the number of cycles in the carrier grating improves modulation detectability.

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