A thin film head for perpendicular magnetic recording

A single pole type thin film head has recently been developed. This thin film head is applicable to perpendicular magnetic recording on rigid disks. The head consists of a Ni-Fe main pole, a spiral coil of 16 turns, and a top magnetic yoke. The thickness of the main pole tip ranges from 0.3 μm to 3.2 μm. Write and read performance were measured using a Co-Cr rigid disk with a Ni-Fe underlayer. The head with a pole tip thickness of 1.2 μm showed the best write performance. Magneto-motive force required for saturation recording was as low as 0.39 AT. In combination with a ring type ferrite head having a very narrow gap to read, isolated output was improved to 1.2 μVp-p/μm/turn at a disk speed of 6 m/s. A waveform was observed up to 90,000 FRPI.