Magnetic and magnetoresistive modification on granular Co-Ag films by soft magnetic permalloy layer

Double-layered structure which is composed of permalloy and granular Co–Ag thin layers has been fabricated by successive sputtering method. Their magnetic and magnetoresistive (MR) characteristics have been studied as a function of the Co–Ag/permalloy thickness ratio. The coercive force decreases with increasing the permalloy layer thickness, indicating the presence of an interlayer magnetic coupling. However, the magnetic saturation field associated with the MR characteristics is maintained to be extremely high. The MR ratios of some double-layered films are larger than that of the Co–Ag single layer.