Exchange Coupling Assisted FePtC Perpendicular Recording Media

Magnetic hard and soft phases FePtC thin films based exchange coupling assisted (ECA) perpendicular recording media were prepared. The coercivity of the FePtC film decreased after introducing a top magnetic soft FePtC layer. The cross-sectional transmission electron microscopy image illustrated that the soft FePt grains were located both on top of the bottom FePt grains and the grain boundaries, where the hard and soft grains were separated by a C layer accumulated on the hard FePtC layer surface. The reduction of coercivity was attributed to the exchange coupling between FePt hard and soft grains. For hard and soft grains separated by the accumulated C layer, the strength of the exchange coupling depended on the carbon layer thickness.