Self-organized growth of Ni clusters on a cobalt-oxide thin film induced by a buried misfit dislocation network

We report on a clear tendency toward organized growth, at room temperature, of Ni nanoislands depositedon a CoO(001) nanopatterned surface. The 9.2 nm square surface patterning consists in a periodic displacementfield induced at the surface by an underlying interfacial dislocations network that is buried at the interfacebetween the 5 nm thick CoO(001) thin film and the Ag(001) substrate. Grazing incidence small and wide anglex-ray scattering GISAXS and GIXD performed in situ, during growth, reveal that the nucleation of Niparticles is driven by the underlaying dislocation distribution. The tendency for organization is confirmed byscanning tunneling microscopy STM, which also reveals a quite narrow size distribution of the Ni nanoparticlesaround 5 nm width and 0.6 nm height.