<i>L</i>1₀FePt–C Nanogranular Perpendicular Anisotropy Films with Narrow Size Distribution

Abstract

We report the study of L10 FePt–C nanogranular perpendicular anisotropy films fabricated on oxidized Si substrates with a (100) textured MgO intermediate layer. The addition of a small amount of C (<12%) to a FePt (4 nm) film results in the formation of interconnected FePt particles, while a higher C addition leads to the formation of well-isolated L10 FePt nanoparticles with a c-axis texture. The FePt particle size can be reduced to 5.5 nm with a size distribution of 2.3 nm in variance by adjusting FePt thickness. Perpendicular coercivity is controllable between 8 and 15 kOe with high squareness. These results demonstrate that the FePt–C system can accomplish a nanogranular structure suitable for ultrahigh density perpendicular recording media.