Nanoporous templates made from diblock copolymer films are used for electrochemical fabrication of hexagonal arrays of vertical cobalt magnetic nanowires at terabit/in2 density. The nanowire diameter and areal density are determined by the copolymer molecular weight, whereas the nanowire length and internal crystal morphology are controlled through the dc electrodeposition growth process. The array magnetic properties can be modified substantially by electrodeposition pH conditions while keeping wire size and interwire distance constant. Optimum pH control results in preferential growth of c-axis oriented crystallites with large perpendicular coercivity. The appearance of exchange bias behavior, exhibited at low temperatures, is also investigated.

Molecular Dynamics simulations were performed to study Cu film deposition on β-Ta. Three different β-Ta surfaces were used, two being atomically flat, and one resulting from Ta on Ta growth. We find that the Cu films develop a (111) texture with vertical grain boundaries between grains having different epitaxial relations with the β-Ta substrate. The epitaxial rotation angles were determined, as 5.2° and 10-13°, and the resulting strain reductions in the Cu films were identified. The effects of the substrate differences on the interfacial Ta/Cu intermixing and the epitaxy and grain boundary structure of the films are discussed.