Mesoporous silicon, achieved by etching of a highly n‐doped wafer is used as template for electrochemical metal deposition. The fabrication of porous silicon samples with a porous layer on each side is performed in a double tank electrolytic cell in applying a pulsed current with a frequency of typically 0.1 Hz. Ferromagnetic metals such as Ni and Co are deposited into the pores of the matrices, either the same metal on both sides of the sample, a different metal on each side or an alloy of both. As substrate material also ultrathin silicon wafers with an average thickness of 60 µm are used to achieve a thickness as small as possible of the remaining bulk silicon in between the two porous layers. These fragile templates are also filled with transition metals and investigated magnetically. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)