Thin Film Head for Perpendicular Magnetic Recording

A single-pole thin film head with various parameters, in combination with rigid disks for perpendicular recording, is described. The head was designed by numerical analysis of the head magnetic field before actual fabrication. An amorphous CoZr thin film was prepared for use as the main pole. Compared with Permalloy, this film had a higher saturation magnetization (16000 G) and higher permeability (5000). Heads were then fabricated with an amorphous CoZr main pole, varying the main pole thickness Tm and the main pole depth Dp. The recording characteristics were evaluated in combination with CoCr double-layer rigid disks. To attain high recording densities, both the main pole thickness Tm and the CoCr layer thickness ¿cocr must be made thin. A half-amplitude recording density D50 of 70 kFRPI was achieved using a head with a 0.2 ¿m pole thickness and a disk with a 0.14 ¿m CoCr layer thickness. The main pole depth Dp had less of an influence on the recording characteristics, meaning a larger tolerance during head manufacture.