Disk drive with laminated magnetic thin films with sublayers for magnetic recording

摘要

The invention includes a disk drive with a magnetic recording disk with an upper and lower sublayer in at least one magnetic layer of a laminated magnetic layer structure that includes a spacer layer that substantially decouples the magnetic layers. The lower sublayer has a lower boron content than the upper sublayer and a preferred embodiment is CoPtCrBTa. The upper sublayer is deposited onto the lower sublayer and is preferably CoPtCrB with a higher boron content than the lower sublayer. The composition of the lower sublayer gives it a very low moment with low intrinsic coercivity which would not be useful as a recording layer on its own. The upper sublayer is a higher moment alloy with high intrinsic coercivity. An embodiment of the invention includes a laminated magnetic layer structure which is antiferromagnetically coupled to a lower ferromagnetic layer.