Structural asymmetry of Si/Fe and Fe/Si interface in Fe/Si multilayers

Abstract

We have investigated silicon on iron (Si-on-Fe) and iron on silicon (Fe-on-Si) interfaces in Fe/Si multilayer(ML) structures. Fe/Si MLs of various Fe and Si layer thicknesses are deposited by the ion beam deposition technique. Structural information on the interfaces is obtained using grazing incidence x-ray reflectivity, x-ray standing wave and cross-sectional transmission electron microscopy measurements. Interdiffusion is greater at the Si-on-Fe interface compared with the Fe-on-Si interface. Silicide interlayer formation is observed at both interfaces. FeSi is the main component of interfacial silicide. The presence of crystalline FeSi and Fe2Si is observed.