Magnetic anisotropies in Focused Ion Beam sculpted arrays of submicrometric magnetic dots

Abstract

Thanks to its high sputtering efficiency and high spatial resolution, Focused Ion Beam (FIB) apparatus has been proved to be effective in isolating magnetic units by direct removal of selected portions of a thin film, at variance with the lithographic process, which involve resist process, etching and cleaning steps. The results is an extremely flexible, reproducible and clean fabrication process. we present a systematic study of the dependence of the surface morphology and geometric shape of Fe square elements and ferromagnetic/antiferromagnetic Fe/NiO bilayer square elements on the FIB parameters. We shown that the final quality of the geometries that can be obtained by FIB milling as well as the residual damage strictly depend on beam parameters (like spot size and pixel dwell time) and on the swelling properties of the patterned materials