Abstract
B was co-sputtered with FePt films, leading to a granular structure; however, in addition to segregating at grain boundaries, local bonding of Fe-B was formed, which suppressed the ordering of FePt and thus degraded the perpendicular anisotropy. A boron capping layer was deposited on FePt:C (28 vol. %) films and B diffused into FePt:C grain boundaries during post-annealing. FePt:(B, C) films revealed a reduced grain size of 5.5nm and perpendicular coercivity of 2T. Co-additions of B and C into FePt films may provide an alternative tuning knob to manipulate the microstructure and magnetic anisotropy of FePt films. © 2014 AIP Publishing LLC.