Interatomic interactions at interfaces of multilayered nanostructures (Co$_{45}$Fe$_{45}$Zr$_{10}$/$a$-Si)$_{40}$ and (Co$_{45}$Fe$_{45}$Zr$_{10}$/Si$_{2}$)$_{32}$

The interatomic interaction and phase formation at interfaces between the metallic layers Co45Fe45Zr10 and nonmetallic interlayers of amorphous silicon or silicon dioxide in multilayered nanostructures (Co$_{45}$Fe$_{45}$Zr$_{10}$/$a$-Si)$_{40}$ and (Co$_{45}$Fe$_{45}$Zr$_{10}$/Si$_{2}$)$_{32}$ have been investigated using ultrasoft X-ray emission spectroscopy (USXES) and X-ray diffractometry. The multilayered nanostructures have been fabricated by ion-beam sputtering of two targets onto the surface of a rotating glass-ceramic substrate. The investigations have demonstrated that, regardless of the expected composition of the interlayer (amorphous silicon or silicon dioxide), $d$-metal silicides, predominantly lower cobalt silicides, are formed at the metallic layer/interlayer interface. However, in this case, the thickness of silicide interfaces in the multilayered nanostructures with oxide interlayers (series O) has a significantly lower value of $\sim$0.1 nm, and, therefore, the central layer of the interlayers remains oxide. In the multilayered nanostructures with amorphous silicon interlayers almost all silicon is consumed in the formation of nonmagnetic silicide phases. When the thickness of this interlayer exceeds the thickness of the metallic layer, the multilayered nanostructures become nonmagnetic.