Magnetic patterning perpendicular anisotropy FePd alloy films by masked ion irradiation

The nanopatterning of magnetic films by ion implantation is reported. Highly L1(0)-ordered Fe47Pd53 epitaxial alloy films on a MgO(001) substrate were covered by a monolayer of silica spheres in a Langmuir film balance. Using this sphere layer as an implantation mask, the samples were irradiated by Ne+ or Fe+ ions with energies of 35 keV and 100 keV, respectively. After the silica mask was removed, the samples were characterized via conversion electron Mossbauer spectroscopy, longitudinal and polar magneto-optical Kerr effect, and atomic force and magnetic force microscopy. We find that the magnetic stripe domains observed in the nonirradiated sample were converted into a regular 2D magnetic pattern of hcp character upon 1 x 10(15)/cm(2) 35 keV neon or 1 x 10(14)/cm(2) 100 keV iron irradiation, with the direction of magnetization remaining out of plane in the nodes of the hcp lattice and relaxed into the film plane in the inter-node region, resulting in an overall in-plane magnetic softening of the film. (C) 2011 American Institute of Physics. [doi:10.1063/1.3596535]