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Nanocrystalline nickel thin films were deposited by magnetron sputtering onto monocrystalline silicon and sapphire, as well as onto fused silica and glass, at room temperature. A sequence of films with varying thicknesses from 15 to 325 nm was prepared by increasing the deposition time twofold in each step. The film thickness is similar for all the substrate types. The film structure has been studied using grazing incidence small angle X-ray scattering (GISAXS). In thinner films (nominal thickness up to 35nm) an island like structure atop the flat film layer is detected for all substrate types, with the island sizes ranging from 4 to 7nm and the inter island distances increasing with thickness from 10 to 35nm. Both the size and inter island distance varied slightly with the type of the substrate. The flat film contribution to the scattering is also present in the form of fringes, and it is strongest on (amorphous) quartz substrate.
In the thicker films (above 35nm nominal thickness) the film to substrate surface correlation is absent. Apart from Porod type scattering, due to the grain agglomeration, an additional contribution from few nm sized inhomogeneities, attributed to grain boundaries, was detected.
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