Effects of CrRu-SiO_x underlayer with MgO intermediate layer on the microstructure and magnetic properties of FePt-C thin film

摘要

The effect of the CrRu-SiO_x underlayer with different doping concentrations and the thickness of the CrRu underlayer on the microstructure and magnetic properties of FePt-C films were investigated. FePt films exhibited L1_0 (001) texture at various SiO_x doping concentrations. The coercivities were as large as 28 kOe and the slope of M-H loop at coercivity was approximately equal to 1, suggesting that FePt grains were well exchange decoupled. Grain size was only slightly reduced after introducing the CrRu-SiO_x underlayer. But the contact angle between the FePt grains and the MgO intermediate layer around 135° indicated the a MgO intermediate layer was not favored for smaller grains to obtain good L1_0 (001) texture. X-ray photoelectron spectroscopy in-depth profile showed that Si diffused into a whole FePt-C layer and C diffused to the film surface.