| It is of importance to improve the growth quality of the single-crystal magnetic nanowire arrays as it has broad applications as perpendicular magnetic recording media. The synthesis and characterization of magnetic nanowire arrays have been investigated in this thesis.Porous anodic aluminium oxide(AAO) templates have been prepared by a two-step anodization process. The effect of processing parameters such as electropolishing, temperature, time, method to remove barrier layer on the order and yield of AAO templates has been analyzed. The suitable processing conditions have been obtained to prepare high quality AAO templates.Highly ordered uniform Fe, Ni and Fe-Ni multi-layer nanowire arrays have been successfully fabricated in self-made AAO templates by DC electrodeposition method. The composition, morphology, structure of nanowire arrays have been characterized by the X-ray diffraction(XRD), scanning electron microscope(SEM) and high-resolution transmission electron microscope(HRTEM). The diameters of nanowires correspond to the pore diameter of the AAO templates and the nanowires are uniform in diameter. The nanowires arrays fabricated by AAO template have obviously preferred orientation along the [110] direction. Ni nanowire is single crystal structure and has growth orientation along [220].Growth condition of single-crystal nanowire has been analyzed by two-dimensional nucleation mechanism. The [110] preferred growth orientation of Fe, Ni nanowire arrays is explained by applying the broken-bond model in combination with surface-energy anisotropy and energy minimization. With analyzing the deposition current-time curve, the growth process of nanowire arrays in the AAO template has been confirmed.The magnetic properties of different aspect ratio(h/d) nanowire arrays have been investigated by vibration sample magnetometer (VSM). The magnetic properties of nanawire arrays with different diameters indicate that the nanowire arrays have obviously perpendicular anisotropy.
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