MAGNETIC RECORDING MEDIUM HAVING IMPROVED OVERWRITING CHARACTERISTIC AND SNR CHARACTERISTIC

摘要

PROBLEM TO BE SOLVED: To provide a magnetic recording medium having improved temperature stability (KuV/kT) and an overwriting function (OW). SOLUTION: The magnetic recording medium 10 has a double magnetic structure layer controlling KuV/kT and SNR separately so as to attain high SNR, the increased overwriting function (OW) and satisfactory temperature stability. The magnetic recording medium comprises a non-magnetic Al-Mg substrate 12 and a NiP layer is nonelectrolytically plated on the surface of the substrate. A Cr seed layer, a Cr based alloy base layer, CoCr alloy intermediate layer and the double film magnetic layer 19 are successively disposed on the substrate by using a sputtering process. A double film magnetic structure comprises an upper first magnetic film 20 consisting of a CoCrPtB alloy and a lower second magnetic film 21 consisting of a CoCrPtTaB alloy, a CoCrPtTa alloy, a CoCrTa alloy or a CoCrPtTaNb alloy. A diamond like carbon(DLC) protective film 22 is sputtered on the first magnetic film.