Magnetic properties, microstructures, and corrosion resistance of high-saturation FeMoN and FeRhN films for recording heads

We:have investigated high-saturation FeMoN and FeRhN films, deposited by ra dio frequency -diode reactive sputtering on alumina-TiC substrates, for ind uctive head applications, A minimum coercivity of similar to 1.2 Oe is obta ined in (Fe97.8Mo2.2)N films:at a N-2/Ar flow ratio of similar to 6.2%, A m inimum coercivity of similar to 1.6 Oe is obtained in (Fe96.9Rh3.1)N films at a N2/Ar flow ratio of similar to 4.6%. The films mainly consist of alpha -Fe phase and gamma'-Fe4N phase, The magnetic properties of these films are stable under easy-axis field:annealing up to 350 degrees C. Addition of Rh or Mo to FeN has resulted in a significant improvement in corrosion resist ance over that of FeN, The localized corrosion resistance of FeRhN and FeMo N can be comparable to that of Permalloy, In contrast, their,intrinsic corr osion resistance is inferior to that of Permalloy, but it can be adjusted a nd controlled by pH level.