Periodic arrays of magnetic nanowires deposited in polycarbonate templates have recently attracted much attention. The arrays have many potential applications in technology, for example in high-density magnetic recording and magnetic sensors. They also attract a significant interest because of being considered as the model systems to study interaction processes and magnetic reversal in low-dimensional magnetic structures.
Nanolithography used as a traditional method to produce periodic arrays of nano-scale magnetic particles, dots, and wires. However, this method is comparatively cumbersome and not suitable for large-area production. In this work we applied electrodeposition as an alternative technique for fabricating magnetic nanowires. This approach is promising for large-area nano-patterning with high aspect ratio, which is usually difficult to achieve by conventional lithography.
We used polycarbonate membranes having cylindrical holes produces by selective etching of the damage track left during irradiation by highly energetic particles. We used commercially available nuclear track etched membranes with the pore diameter of 80 nanometer and the 6 micron deep holes. Gold is evaporated onto one side of the membrane, which is used as a cathode in an electrolyte cell. After electrodeposition, an assembly of nano-wires with a length of 6 micron and a diameter of 80 nanometer is achieved.
X-ray diffraction, scanning and transmission electron microscopy were used to characterize the Ni nanowire arrays. The results indicate that the growth nanowires are polycrystalline though the grain sizes are relatively large.
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