Displacements of Sb atoms in supersaturated Sb-doped Si layer formed by molecular beam epitaxy growth

Rutherford backscattering channeling measurements with angular scans have been carried out on $⟨100⟩$ Sb-doped Si superlattice structures formed by molecular beam epitaxy growth. Three different crystallographic axes $⟨100⟩$ , $⟨111⟩$ , and $⟨110⟩$ have been explored. We have observed Sb displacements from their substitutional sites with displacement amplitudes of 0.22 Å in as-grown samples. The displacements increase with increasing post-growth annealing temperatures, associated with formation of nanometer size Sb precipitates.