Writing performance of narrow gap heads made with sputtered laminated FeN materials on 3800 Oe coercivity media

Recording results of write heads using sputtered laminated FeN/Al ₂O₃ materials on thin film media with coercivity up to 3800 Oe are compared with those obtained using plated NiFe materials. The thickness of P2 (second pole) of FeN merged write heads is about 3.2 μm, and those of plated NiFe heads, 3.5 and 6.3 μm respectively. These heads have two write gap thickness, around 0.2 and 0.4 μm. Various recording measurements show that these high magnetization FeN heads of 0.15 μm gap write well on media of 3800 Oe, while the corresponding NiFe ones with a P2 of twice the thickness could not. For a wide 0.39 μm gap, the FeN write heads still work well and the NiFe ones with twice the pole thickness, also did, but at reduced resolution, In short, write heads using a narrow gap and high magnetization materials such as FeN can write 3800 Oe coercivity media, which is capable of storing a bit density over 10 Gb/in²