Co-based superstructured nitride alloy films: characteristics and applications for high frequency heads

Co-based superstructured films composed of 25-nm-thick non-nitride and nitride layers were prepared by N/sub 2/ reactive RF sputtering. The films have high 4 pi M/sub s/=13 kG, a high permeability mu =3000, and a high thermal stability of the magnetic properties. Magnetic heads composed of laminated superstructured films insulated with SiO/sub 2/ films were developed for high-frequency operations. The heads show excellent recording capability for narrow gap recording with metal tapes and high reproduction characteristics at frequencies over 10 MHz. They achieve an increase of more than 4 dB in normalized output when compared with conventional laminated-type amorphous film heads. The superstructured nitride film heads are expected to be used in next-generation VCRs, which operate with higher density recording and wider frequency bands.>