5 Gb/in/sup 2/ recording demonstration with NiFe/Co/sub 90/Fe/sub 10/ spin-valve heads and low-noise thin-film disks

A high areal density of 5 Gb/in/sup 2/ (7.75 Mbit/mm/sup 2/) has been demonstrated with narrow track NiFe/Co/sub 90/Fe/sub 10/ spin-valve read heads on low-noise CoCrTaPt/CrMo-alloy thin-film disks. The MFM measurements clearly showed the write track width to be 1.2 /spl mu/m on the CoCr/sub 17/Pt/sub 5/Ta/sub 4/ thin-film media. This corresponds to 19.5 kTPI (768 track/mm) including a guard band of 0.1 /spl mu/m. The error rate performance was tested using a PR4ML channel with write precompensation. At a data rate of 33 MB/s, a practical error rate of 9.0/spl times/10/sup -6/ was obtained without error correction at a linear density as high as 257 kBPI (10.1 kbit/mm). At a linear density of 217 kBPI (8.5 kbit/mm), we obtained an error rate of less than 10/sup -8/ without error correction. With a 192-bit Reed-Solomon error correcting code, we can expected an error rate of 1.0/spl times/10/sup -14/.