Abstract
The recording and the signal decay characteristics of longitudinal and perpendicular thin film media are studied to investigate the limitations and the possibilities of CoCr-alloy thin film media. The CoCrTa and the CoCrPt perpendicular media show 25-32% higher recording resolution than those of the CocrPt longitudinal media. The medium S/N measured at 300 kFCI is in the order : CoCr_<20>Pt_<10>(L, 8nm)>CoCr_<17>Ta_4(P, 25nm)〜CoCr_<20>Pt_<10>(L, 16nm)>CoCr_<19>Pt_<10>(P, 25nm). The signal decay rates measured for a high Mr/Ms perpendicular medium is below 1 % per decade of time for all linear densities. The decay rate of longitudinal medium increases with increasing the linear recording density and with decreasing the recording layer thickness and it exceeds 10%/10^5 seconds at 300 kFCI with the thickness of 16 nm. The CoCr-alloy perpendicular recording media are promising, though the noise needs to be further reduced, to extend the linear density well beyond 400 kFCI which is likely needed to achieve the areal density greater than 20 Gb/in^2.
