Development of advanced barium ferrite tape media

We developed an advanced particulate magnetic tape using fine barium ferrite (BaFe) particles for magnetic-tape storage systems. The new tape showed a signal-to-noise ratio (SNR) that was 3.5dB higher than that of the commercially available BaFe tape used for the Linear Tape Open generation 6 tape-storage system, at a linear density of 300kfci measured with a giant magnetoresistive head with a reader width of 0.45µm. Such significant increase in SNR was achieved by reducing the magnetic particle volume from 1950 to 1350nm3, while maintaining a sufficiently high thermal stability, improving the perpendicular squareness ratio from 0.66 to 0.83, and improving the surface roughness from 2.5 to 2.0nm when measured by atomic force microscopy and from 2.4 to 0.9nm when measured by optical interferometry. This paper describes the characteristics of the new BaFe particles and media, which are expected to be employed for future high-capacity linear-tape systems.