Transmission electron microscopy characterisation of ion beam synthesised FeSi2 layers

The epitaxial relationships in buried FeSi2 layers prepared by ion beam synthesis at elevated temperatures in both (111) and (100) silicon substrates are investigated by means of conventional and high-resolution transmission electron microscopy and electron diffraction in as-implanted and annealed samples. Except for two epitaxial relationships between the beta-FeSi2 grains and the silicon previously reported for other preparation techniques, a new relationship is also identified. Misfit dislocations are observed on the silicide/silicon interface and slacking faults in the grains. In as-implanted samples and in material annealed at 1150 degrees C, alpha-FeSi2 occurs both aligned and twinned with respect to the silicon substrate.