Abstract
The structural stability and coalescence of self-assembled FePt monolayer nanoparticles on functional substrates with/without an Au overlayer during annealing were studied. From X-ray diffraction and the anomalous grazing-incidence small-angle X-ray scattering techniques, the nanoparticles were found to be intact under the annealing process when a 5-10 nm overlayer of Au was deposited on top of FePt monolayer nanoparticles. From the simulation result, the particle size 4.5 ± 0.5 nm is typically unchanged, but the distance between particles is reduced from 7.5 ± 1.5 nm to 5.5 ± 1.1 nm after annealing. The results suggest that the 5 nm Au coverlayer is an effective diffusing barrier layer to prevent the FePt nanoparticles from sintering during the annealing process. © International Union of Crystallography 2007.