抄録
The shaping of the pole tip configuration of inductive thin film heads, at the air bearing surface by ion milling, is thought to be one of the promising technologies to boost the areal density of the disk drives. It was found to realize the undershoot suppression of the isolated readback waveform, which enables the heads to adapt to the PRML read/write channel processing easier. Further, the off-track capability was also found to be improved by truing up the track side edges of both upper and lower poles. The latter was achieved by trimming both sides of the upper and lower pole tips of inductive thin film heads to become nearly the same in width, through photolithography and ion milling processes at the air bearing surface. The off-track capability enhancement attained by the pole trimming was experimentally estimated by performing off-track profile evaluation and "747 curve" measurement. The difference between the effective track width and the upper pole width (ETW-P2W), which represents the amount of the effect of track side writing and side crosstalk, was found to be reduced to 68% of that seen in conventional thin film heads. It was also found that the track interval can be squeezed by as much as 1.0 μm more than conventional thin film heads, based on the 747 curve comparison.
