Epitaxy in Fe₃Si/FeSi₂ superlattices prepared by facing target direct-current sputtering at room tempertaure

Fe₃Si/FeSi₂ superlattices were prepared on Si(111) at two deposition rates by facing target direct-current sputtering. For the deposition rates of 2.0 nm/min for Fe₃Si and 1.3 nm/min for FeSi ₂, the Fe₃Si layers were nonoriented. On the other hand, for half-deposition rates, the Fe₃Si layers were epitaxially grown not only on Si(111) but also up to the top layer across the FeSi₂ layers. The antiferromagnetic interlayer coupling between the Fe₃Si layers was induced in the epitaxial superlattices, whereas it disappeared in the nonepitaxial superlattices. The regular accumulation of highly oriented Fe ₃Si layers is crucial for the interlayer coupling induction.