A new metastable epitaxial silicide: FeSi2/Si(111)
نویسنده
چکیده
A metastable phase of FeSi 2 that is not present in the bulk phase diagram can be grown epitaxially on Si(111). Scanning tunneling microscope images reveal the surface reconstruction of this phase and allows one to model its crystallographic structure. It crystallizes with a cubic structure, probably a fluorite structure like CoSi 2 and NiSi2, lattice-matched to Si. The (111) surface has a 2 × 2 reconstruction according to LEED. The origin of this reconstruction is reported here for the first time. It is due to a superstructure of Si adatoms with local bonding similar to that of the adatoms in the S i ( l l l ) 7 x 7 reconstruction.
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