Highly Sensitive Single-Pole Thin Film Head

The return path core of a single-pole thin film head for perpendicular recording was extended up to the top surface of the head in order to improve the reproducing sensitivity. In this type of head, as the gap length between the main pole and the return path core decreases, the reproducing sensitivity increases, while distortion of the reproduced waveform caused by the contour effect of the return path core increases. We developed a new head, the return path core of which has a waved edge, in order to reduce the distortion of the reproduced waveform. The waved edge was formed by the ion milling process. The azimuth effects of the waved return path on the recording characteristics, reproduced waveform and peak-shift characteristics was investigated through simulations and experiments. The new head has high sensitivity, low waveform distortion, and small peak-shift displacement.