Scattering of Å-scale electron probes in silicon

We use frozen phonon multislice calculations to examine the scattering behaviour of A-scale electron probes in <001> and <110> silicon. For each crystal orientation, we consider the distribution of scattered intensity in real space as a function of crystal thickness, probe size and probe position. The scattered intensity distribution is found to vary drastically for different probe sizes. For a given probe size, the scattered intensity distribution is also significantly influenced by the crystal orientation. We discuss the implications for the simultaneous acquisition of an annular dark-field image and electron energy loss spectra in the scanning transmission electron microscope, with specific reference to the spatial resolution with which electron energy loss spectra can be related to local atomic structure. (C) 2003 Elsevier Science B.V. All rights reserved.