A study on magnetic properties and structure of SmCo5 thin films on Ni–W underlayers

Abstract A systematic study on Ni–W alloy underlayers has shown that a highly textured (2 1 1)-Ni 4 W can be formed after deposition at room temperature. Highly textured (0 0 0 1)-SmCo 5 with a high out-of-plane coercivity (over 10 kOe) and large perpendicular anisotropy can be obtained after deposition on the (2 2 1)-Ni 4 W underlayer probably due to a small mismatch between (2 2 1)-Ni 4 W and (0 0 0 1)-SmCo 5 . Our study indicates that the surface roughness of the underlayers also plays a crucial role, that a smooth surface is favorable for a good crystallinity and high coercivity of SmCo 5 . Moreover, we found that a highly textured Ni-(1 1 1) can be obtained on the top of the (2 1 1)-textured Ni 4 W. The film structure of SmCo 5 /Ni/Ni 4 W may be interesting as the hard/soft double-layered film for perpendicular magnetic recording or for other applications after a further development.