A study of multilayer nanostructures [(Co45Fe45Zr10)35(Al2O3)65/a-Si:H]100 and [(Co45Fe45Zr10)35(Al2O3)65/a-Si]120 by means of XRD, XRR, IR spectroscopy, and USXES

Abstract

Interatomic interactions and superstructures of multilayer nanostructures (MLNS) consisting of ferromagnetic composite layers and silicon interlayers with or without hydrogen are studied here by means of X-ray diffraction (XRD), X-ray reflectivity (XRR), IR spectroscopy, and ultra-soft X-ray emission spectroscopy (USXES). The MLNS [(Co45Fe45Zr10)35(Al2O3)65/a-Si:H]100 and [(Co45Fe45Zr10)35(Al2O3)65/a-Si]120 were deposited on the substrate Si(100) by ion-beam sputtering of two targets, where the first target was a plate of Co45Fe45Zr10 alloy with Al2O3 inserts, and the second target was a single-crystal silicon. Our results show that the iron (FeSi2) and cobalt (CoSi, CoSi2) silicides are formed at the interfaces of the composite metal-containing layer/silicon interlayer. It is demonstrated that the metal clusters of composite layers and interface silicides are partially oxidized to form iron, cobalt, and silicon oxides together with zirconium silicate. Due to the formation of silicides at the interfaces, the composition of MLNS superstructures becomes more complex, and their periods are significantly reduced (down to 5–6 nm) compared to the nominal values of bilayers of about 6.9 nm.