Ordered nanoporous nickel films and their magnetic properties

Ordered nanoporous nickel (Ni) films were fabricated by a full-replicated process. Replicated from an alumina membrane, the replicated Ni film has a very high aspect ratio of about 360, an ordered nanopore array structure, and a narrow size distribution of the pore diameters. Due to the peculiar fabrication processes, the replicated Ni film is polycrystalline with clear ferromagnetic behavior, which is totally different from that of conventional electroless deposited Ni films. The replicated Ni film does not possess obvious magnetic anisotropy, which is also different from a typical ferromagnetic thin film.