Exchange coupling assisted FePtC perpendicular recording media

Abstract

Exchange coupling assisted perpendicular recording media consisting of a 10 nm magnetically hard FePtC layer with a FePtC soft overlayer of a different thickness were investigated. Both the coercivity and the saturation field of the FePtC film decreased after introducing a magnetically soft FePtC overlayer. The soft FePt grains were located on top of the underlying FePt grains and at the grain boundaries. Some of the hard and soft grains were separated by a C layer accumulated on the hard magnetic FePtC layer surface. The strength of the exchange coupling between soft and hard grains depended on the C layer thickness.