Development of L10-ordered FePt Thin Film for Magnetic Recording Application

<div>L1₀ FePt is a promising material candidate for heat assisted magnetic recording (HAMR) and spintronic device applications due to its superior physical properties, such as</div><div>excellent magneto-crystalline anisotropy, high saturation magnetization, good spin polarization efficiency, good chemical stability, etc. To control the long-range chemical</div><div>ordering (S), texture, magnetic properties, microstructure, and other physical properties such as Curie temperature (Tc) and anisotropy field (Hk) are the keys in developing</div><div>suitable nanostructured L10 FePt for different applications. Despite the significant research progresses in developing L1₀ FePt nanostructured thin film for HAMR media in</div><div>recent years, there are still many remaining challenges. This research aims at exploring for potential solutions and providing an alternative way of thinking to tackle these</div><div>challenges. One critical challenge related to developing L1₀ FePt for HAMR application is to control the texture of FePt nano-grains and reduce the number density of multi-variant FePt grains. Ideally, small perpendicularly ordered FePt grains with c-axis perpendicular to the film plane without c-axis distribution are desired. However, in reality, the presence of polycrystalline MgO underlayer grain boundaries, MgO (002) texture distribution, and its surface roughness will lead to FePt c-axis distribution and formation of multi-variant FePt grains. In this research, the effect of inserting an annealed Cr buffer layer beneath MgO underlayer and inserting a prefabricated MgO-C template layer on top of MgO underlayer on the texture and magnetic properties of FePt nano-grains are studied.</div>