C/FePt/Fe纳米薄膜的微结构和磁特性

利用超高真空磁控溅射方法制备了一系列不同C层厚度的C/FePt/Fe纳米薄膜,然后进行原位高温退火。应用X射线衍射仪(XRD)分析了样品的晶体结构,利用扫描探针显微镜(SPM)观测了表面形貌和磁畴结构,通过振动样品磁强计(VSM)测量了磁性。结果表明,薄膜的微结构和磁特性随C覆盖层厚度的变化有着非常显著的变化。C的加入使样品表面更加光滑,使10 nm厚的C覆盖层样品获得了0.3 nm的粗糙度和3.8 nm的颗粒尺寸。C覆盖层减弱了磁性颗粒间的磁偶极作用,同时减弱了磁性颗粒间的交换耦合作用,提高了L10织构的有序化程度,进而增大了样品的矫顽力,矫顽力达到了987 kA/m。

Microstructure and Magnetic Properties of C/FePt/Fe Nanofilms

C/FePt/Fe nanofilms with different thicknesses of the C layer were fabricated by DC magnetron sputtering and subsequently annealed in situ vacuum.The crystal structures were analyzed by the X-ray diffraction(XRD),the morphologies and magnetic domain structures were observed by the scanning probe microscope(SPM),and the magnetic properties were measured by the vibrating sample magnetometer(VSM).The result shows that the microstructure and magnetic properties of C/FePt/Fe films depend strongly on the thickness of the C capping layer.The surface of the sample becomes more smooth because of C.The particle size and magnetic domain are decreased,the roughness degree is 0.3 nm and particle size is 3.8 nm when the C layer thickness is 10 nm.As a function of the C capping layer,the magnetic intergranular binding energy and strong exchange coupling function were reduced,the ordered L10 texture was improved,and the huge coercivity about 987 kA/m was obtained in the C(10 nm)/FePt(15 nm)/Fe(1 nm) film.