Magnetic properties and microstructure of FePt/MoC/CrRu films

• The MoC conductive intermediate layer was resisted the Cr diffusion.
• The MoC layer promote the epitaxial growth of (001) textured FePt film.
• The FePt film shows perpendicular magnetization on MoC layer.

The FePt films with thickness of 4−10 nm were deposited on MoC/CrRu/glass at substrate temperature ranged from 260 to 410 °C by using magnetron sputtering and strong (001) textured FePt films were obtained at 380 °C and 410 °C. The multi-functional MoC conductive intermediate layer was used to resist the Cr diffusion and promote the epitaxial growth of the (001) textured FePt film which shows perpendicular magnetization and a linear-like in-plane magnetic loop. The out-of plane coercivity and shape of demagnetization curve were dominated by the ordering degree and perpendicular magnetic anisotropy which were increased with deposited temperature. The FePt film deposited at 290 °C shows continuous morphology and change to interconnected structure at 350 °C and finally form the island like structure at 380 °C and 410 °C. Each island contains many FePt grains and the smaller grains size was 12.2 nm which obtained at 5 nm thick FePt film. Perpendicular anisotropy of 1.1×107 erg/cm3 and coercivity of 8.2 kOe have been demonstrated in 7 nm thick FePt film.