Thickness Dependent Structural and Magnetic Properties of Au/Co/Si (100) Ultra-thin Wedge Film.

In the present study, the investigations on an ultra thin wedge thin film prepared by Ion Beam Sputtering (IBS) technique are presented. This film consists of a Co ultra thin wedge layer (thickness ranging from 0.5nm-4nm)sandwiched between a pair of Au layers. The thickness dependent structural and magnetic properties measured are reported. Three different locations, the lowest, middle and the highest thickness were probed for the present work. The X-ray reflectivity measurements reveal roughness induced intermixing of Co and Au layers. However, no signature of alloy formation is observed. X-ray diffraction measurements show polycrystalline nature of film. The hysteresis loops are not properly seen on lowest thickness side of film due to very less number of magnetic Co particles, but when the thickness is high enough show the ferromagnetic character then clear ferromagnetic hysteresis loop is observed and the coercivity is seen to increase with increase in Co layer thickness. The overall results are interpreted in terms of growth of Co particles in between adjacent Au layers. [ABSTRACT FROM AUTHOR]