LAUSR

An IrMn top-nailed spin-valve multilayer film was synthesized using direct-current magnetron sputtering on a naturally oxidized silicon substrate. The multilayered film microstructure and magnetism were analyzed using x-ray diffraction, transmission, and atomic force microscopies as well as vibrating sample magnetometry as functions of ion irradiation. The reverse saturation field residence time of the spin-valve multilayered sample was used to assess its magnetic stability. Ga+ distribution in the layers after irradiation was also simulated using the SRIM2003 package. Ga+ irradiation weakened the intensity of the (111) peak of the antiferromagnetic IrMn (111) layer, decreased surface roughness as well as exchange bias field and pinned layer coercive force, while increasing the free layer coercive force. However, the multilayer exchange bias field of the spin-valve film under the reverse saturation field after Ga+ irradiation did not change with time.