MAGNETIC STABILITY OF FE-9.0WT-PERCENT-SI/PERMALLOY MULTILAYERED FILMS IN HIGH-TEMPERATURE PROCESSES

Fe-9.0wt%Si/permalloy multilayered film has high initial permeability. However, the permeability decreases drastically after annealing at above 400-degrees-C because of the Ni diffusion at the boundary between permalloy and Fe-Si layers. We tried to improve the magnetic stability of the multilayered films in high temperature annealing in magnetic head fabrication processes. However, the crystallization is disordered during a high temperature process because of the diffusion at the boundary. Depositing each Fe-Si layer in more than 0.6-mu-m thickness and using a lower Ar pressure, such as 3mTorr, good soft magnetic properties can be obtained even after annealing at 500-degrees-C.