Magnetic Patterning of the Ni/Cu Thin Film by 40 keV O Ion Irradiation

Abstract

Ni(60Å)/Cu film possessing perpendicular magnetic anisotropy (PMA) changes its easy direction into the plane by ion irradiation, due to the relaxation of the strain. By fixing our eyes upon this magnetic property, the magnetic patterning of Ni(60Å)/Cu film using 40 keV O ion irradiation was performed through the photo-resist (PR) mask having 10㎛ x 10 ㎛pattern sizes to pattern the magnetic film. After the PR mask removal of an irradiated film, the magnetic properties were investigated by the magneto-optic Kerr effect and the formation of magnetic pattern was observed by the magnetic force microscopy. The PMA magnetic patterning of epitaxial Ni/Cu film was successfully performed in scale of ㎛ by using ion irradiation, compatible with device process.