2013 Volume 11 Pages 99-104
Ion beam induced dewetting of thin metallic films has emerged as a promising way to grow metallic nanoparticles in a controlled manner. Metal films tend to dewet from non-reactive substrates upon heating, forming islands, due to the high energies of metal surfaces and interfaces. Ion beam irradiation triggers the self organized formation of nanostructures, and allows control over nanoparticle size distributions, since dewetting is initiated by highly localized (in space and time) thermal spikes along the ion track. From 25 nm cobalt films grown by e-beam evaporation, followed by irradiation with 100 keV Ar+ ions, a high density array of nanostructures is formed. AFM scans show their morphological evolution as a function of ion fluence; optimum fluences for narrow particles size distribution have been identified. Glancing angle XRD and Rutherford Backscattering Spectroscopy show evidence of increased substrate exposure as dewetting proceeds. RBS indicates that within the optimal fluence range for nanostructure formation, sputtering and ion beam mixing are not the significant effects in this system. We present ion beam induced dewetting as a well controlled method of forming nanostructured catalysts from metal films. [DOI: 10.1380/ejssnt.2013.99]
