Interface structure of Fe/Ag multilayers prepared by pulsed laser deposition

Fe/Ag multilayers with single layer thicknesses in the nanometer range have been deposited on Si(100) using pulsed laser deposition. Conversion electron M\"ossbauer spectroscopy in conjunction with Rutherford backscattering spectrometry and x-ray reflectivity have been used for the evaluation of the interface structure of these multilayers. In the Fe-Ag system, with a large positive heat of mixing, a solid solution of bcc Fe(Ag) has been found by placing an enriched ⁵⁷Fe marker layer at different distances to the multilayer interfaces. The interface structure mainly depends on dynamic effects during the deposition processes. From the analyses, we have obtained an asymmetric intermixing at lower and upper interfaces of the individual Fe layers: the intermixing of Fe into Ag is lower than that of Ag into Fe. The studies of the interface structure were performed by varying parameters such as the thickness of the elemental layers and the target-to-substrate distance during the deposition process.