Semiconducting MnSi1.7, and beta -FeSi2 layers were grown by the use of Sb surfactant mediated reactive deposition epitaxy (RDE) on Si(111) substrates. The defect microstructure and epitaxial relationship of the layers were examined by transmission electron microscopy (TEM) and the X-ray diffraction technique. Epitaxial MnSi1.7 grown on a Si(111) substrate, adopts the (332),[(1) over bar 10]MnSi1.7 subcell / / (111),[(1) over bar 10]Si epitaxial relationship, where the (332)MnSi1.7 subcell plane is equivalent to, for example, (3322) and (3330) for Mn11Si19 and Mn15Si26, respectively. It has been found that a continuous and relatively smooth beta -FeSi2(101)/(110) layer could be also deposited. It is considered that the growth method examined here might be further developed for the deposition of single-phase, high-quality epitaxial layers of other multiple phase alloys.