title: The contribution of phonon scattering to high-resolution images measured by off-axis electron holography.
abstract: The contribution of electrons that have been phonon scattered to the lattice fringe amplitude and the background intensity of a high-resolution electron microscope (HREM) image is addressed experimentally through the analysis of a defocus series of energy-filtered off-axis electron holograms. It is shown that at a typical specimen thickness used for HREM imaging approximately 15% of the electrons that contribute to an energy-filtered image have been phonon scattered. At this specimen thickness, the phonon-scattered electrons contribute a lattice image of opposite contrast to the elastic lattice image. The overall lattice fringe contrast is then reduced to 70% of the value that it would have in the absence of phonon scattering. At higher specimen thickness, the behaviour is defocus-dependent, with the phonon image having lattice fringe contrast of either the same or the opposite sense to the elastic image as the defocus is varied.
authors.affiliation: IMRE, 3 Research Link, Singapore 117602, Singapore. chris-b@imre.a-star.edu.sg
authors.forename: C B
authors.initials: CB
authors.lastname: Boothroyd
authors.forename: R E
authors.initials: RE
authors.lastname: Dunin-Borkowski