High density magnetic recording on highly oriented CoCr-alloy perpendicular rigid disk media

High density magnetic recording is investigated for a combination of single-layered perpendicular media and ring-type heads. Medium magnetic properties (Hc and Mr/Ms) are improved by introducing a dual underlayer structure. Read/write experiments show that the linear recording resolution (D₅₀) increases drastically with decreasing magnetic spacing. D₅₀ values of 190-220 kFCI are observed using a flying MR head at an estimated magnetic spacing of 40 nm. Using contact recording, even higher resolution of D₅₀*=300 kFCI is confirmed. Side-writing and side-erasing can be reduced below 0.2 μm by employing a narrow gap write head with trimmed sharp track edge, which demonstrates the possibility of track density greater than 25 kTPI. The recording areal density can be increased to the 10 Gb/in² level with the present recording system