Fe-based alloy laminated films with crossing easy axis structure and their applications to laminated film heads for high-frequency use

To realize laminated film heads with superior recording and reproducing capability in high frequency region, we have investigated Fe-based alloy (Bs=1.6 T) laminated films with different laminating structures: one with magnetostatically coupled laminated films and the other with laminated films having crossing easy axis structure. Although the magnetostatically coupled Fe-based laminated films show high initial permeability even in a narrow shape area near the magnetic gap, they have anisotropic initial permeability, and therefore the laminated film head using this film shows lower playback output compared with conventional Go-based amorphous film head below 20 MHz. The Fe-based laminated film with crossing easy axis structure with 5 nm SiO2 shows isotropically high initial permeability in high frequency region and maintains high initial permeability even in a narrow shape area near the magnetic gap. Consequently, the laminated film head using this film shows excellent recording and reproducing characteristics for metal particle tape (MP-tape) for wide frequency ranges.