NiFe/CoFeB spin-valve heads for over 5 Gbit/in(2) density recording

This paper outlines the successful use of NiFe/(Co90Fe10)100-xBx (x = 5, 10%) for soft magnetic, thermally stabilized spin-valves, The GMR effect in the NiFe/CoFeB spin-valve increases after annealing. The annealing effect of CoFeB on CoFeB/Cu interfaces is investigated by high resolution TEM-EDX analysis, Merged inductive NiFe/CoFeB spin-valve heads with a read gap length of 0.18 mu m and a write gap length of 0.28 mu m having NiO(400 Angstrom)/NiFe(10 Angstrom)/CoFeB5(10 Angstrom)/Cu(32 Angstrom)/CoFeB5(20 Angstrom)PTa(100 Angstrom) spin-valve film and high Bs laminated FeZrN/NiFe top poles were fabricated, Their read/write performance were tested on a low noise CoCr19Pt5Ta2Nb2 thin-film disk with an Mrt of 0.6 memu/cm(2) and a coercivity of 2600 De. A normalized output per track-width of 1000 mu Vpp/mu m and a 50% rolloff linear density (D50) of 182 kFCI is obtained, This performance well exceeds the performance of 5 Gbit/in(2) spin-valve heads, The measured S/N was 26.8 dB for a spin-valve head with with a narrow read track-width of 0.68 mu m, and the feasibility of 8 G bit/in(2) recording density is studied using a 1/7 code Narrow Band PRML channel.