Grain size refining and microstructure of FePt/MgO nanogranular thin films

A MgO (1 similar to 8 nm) single layer was inserted into Fe/Pt multilayers to introduce controllable defects on the interfaces between the MgO and Fe/Pt multilayers. The insertion of the MgO layer effectively reduced the average grain size and the size of the magnetic domains. The out-of-plane coercivity of the FePt films decreased with increasing thickness of the MgO insert layer. Transmission electron microscopy observation revealed that the average grain size of FePt/MgO. lms is controlled to be around 9 nm and thus suitable for application in future high-density recording media. (C) 2006 Elsevier B.V. All rights reserved.