Magnetic nanocomposites fabricated by selective metal deposition in and on self-assembled mesoporous silicon

The fabricated mesoporous silicon structures, self-assembled and grown, exhibit separated oriented channels perpendicular to the sample surface in an adjustable diameter range between 30 nm and 100 nm depending on the applied current density. These matrices with more or less regular arranged pore patterns with tuneable pore diameter and pore distance are electrochemically loaded with a metal (Ni, Co) in a cathodic process. To achieve a ferromagnetic specimen a metal-salt solution is used as a plating electrolyte. Depending on the pulse duration of the applied current the channels of the porous material are filled with metallic nanostructures of different sizes and shapes. This electrochemical two-step process is appropriate to produce a silicon-based nanocomposite system which permits the adjustment of the magnetic properties depending on the morphology of the porous silicon template as well as on the different filling conditions of the channels.