Magnetic Properties of ThMn12-Type Sm-Rich Sm-Fe-Co Thin Films with V Buffer Layer

In order to realize a highly oriented ThMn12- type Sm(Fe, Co)12 thin film, the effect of the compositions of Sm and Co on the crystal structure and magnetic properties for Sm- rich Sm-Fe-Co thin films have been investigated. Sm-Fe-Co thin films were prepared by an ultra-high vacuum sputtering system on MgO (100) single crystal substrate with V (100) buffer layer. The composition was confirmed to be Smα(Fe100-xCox)100-α (α= 7.7 ~ 18.5, x = 0 ~ 39.3 at.%). From XRD patterns, (002) and (004) peaks from ThMn12-type phase were observed, and (132) and (332) superlattice peaks were also clearly observed. The highly orientated Sm(Fe,Co)12 phase was obtained for Sm13.7Fe69.0Co17.3 (at.%) thin films and saturation magnetization MS of 1263 emu/cm³, squareness (Mr/Ms) of 67.3 % and uniaxial magnetocrystalline anisotropy Ku of 44.7 Merg/cm³ were obtained.