Monolayered Ni-Co alloy nanoparticles template fabricated using a Ni nanoparticle array

A monolayer of Ni-Co alloy nanoparticles in the nanometer-size regime was fabricated on a polyimide film by depositing a 3.5-nm-thick Co thin film on top of the nanosized Ni nanoparticle template followed by thermal annealing. The Ni-Co alloy particles exhibited a dramatic increase in saturation magnetization, especially when the samples were annealed using rapid thermal annealing. The blocking temperature of the nanoparticles also increased to 230 K. Such a nanoparticle template process presents a possibility of synthesizing a variety of monolayered nanoisland structures for applications such as nanomagnet arrays, nanophotonic arrays, or nanocatalyst arrays. (c) 2006 American Institute of Physics.