Tiberto, P. and Gupta, S. and Bianco, S. and Celegato, F. and Martino, P. and Chiolerio, A. and Tagliaferro, A. and Allia, P. (2011) Morphology and magnetic properties of island-like Co and Ni films obtained by de-wetting. Journal of Nanoparticle Research, 13 (1). pp. 245-255.
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Official URL: http://www.springerlink.com/content/0w0r63w1946322...
The morphological, structural, and magnetic properties of Co and Ni films of different thicknesses grown by RF sputtering on a Si-SiO substrate and submitted to controlled diffusion of atoms on the substrate (de-wetting) are studied through X-ray diffraction (XRD), atomic force microscopy, X-ray photoelectron spectroscopy, and alternating-gradient magnetometry. For both metals, de-wetting treatment leads to the growth of non-percolating, metallic nanoislands characterized by a distribution of sizes and aspect ratios. XRD spectra reveal a polycrystalline multi-component structure evolving by effect of de-wetting and directly affecting the magnetic properties of films. The magnetic response after de-wetting is consistent with the formation of a nanogranular magnetic phase characterized by a complex, thickness-dependent magnetic behavior originating from the simultaneous presence of superparamagnetic and blocked-particle contributions. At intermediate film thickness (around 10 nm), a notable enhancement in magnetic coercivity is observed for both metals with respect to the values measured in precursor films and in their bulk counterparts.
|Subjects:||Physical Science > Nanophysics|
Physical Science > Nanomagnetics
|Divisions:||Faculty of Engineering, Science and Mathematics > School of Engineering Sciences|
Faculty of Engineering, Science and Mathematics > School of Chemistry
|Deposited On:||30 Apr 2011 12:16|
|Last Modified:||30 Apr 2011 12:16|
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