Recording characteristics on thin metal evaporated media in a helical-scan tape system with a spin-valve head

The recording characteristics of Co-CoO metal evaporated (ME) tapes with a giant magnetoresistive head have been investigated. The reproduced spin-valve head output was 7.6 times that of an anisotropic magnetoresistive head at a recording wavelength of 0.4 μm. We also studied the relation between the carrier-to-media noise (C/N_media) ratio and remanent magnetization (Mr) magnetic layer thickness (t) in the ME tape. The media noise level was reduced with decrease in Mr · t by the increase of the oxygen flow rate, whereas the C/N_media ratio of the tape with a magnetic layer thickness of 33 nm was maximized at around 10 mA. We thus confirmed the feasibility of an areal density of 3.8 Gb/in² in a helical-scan tape drive system.