The Effect of Ion Implantation on Magnetic Properties of CoPd Multilayer Structures Possessing Perpendicular Anisotropy

Focused ion beam (FIB) milling is a well-established technique for micro- and nano-fabrication of prototype media and devices. However, the key advantages of this method must be carefully balanced against its inherent problems such as ion implantation to the treated matrix and secondary deposition of the milled material. In this work, we report the effect of Ga+ ion implantation in multilayer CoPd matrix on the materials' magnetic properties. The dependence of the effect on both the irradiation dosage and the ion energy is studied. We observe a significant effect at irradiation doses as low as 1 * 10(14) ions/cm(2), approximately 10 times lower than previously reported. However, the total magnetic moment of the medium is not affected, while the anisotropy of the material changes from out-of-plane to in-plane. No effect of implantation is observed at ion energies at and below 5 keV.