Film heads for large-capacity fast-access magnetic disk storage

Increasing the pole thickness of film heads is effective in improving the strength of write fields. This is necessary to handle the high coercive force(Hc=63kA/m) thin film media utilized in the large-capacity, fast-access disk storage[1] nicknamed GEMMY. Film heads with thicker poles are designed for storage devices. These heads achieve a linear density of 1240bit/mm(940 fc/mm) and a transfer rate of 4.4MB/sec (26.3Mfc/sec).