Enhancement of Coercivity for Sm(Fe-Co)₁₂-B Thin Films by Introduction of Sm Seed Layer

Abstract

To improve the coercivity of Sm(Fe-Co)12-B thin film, a Sm seed layer was introduced between a V buffer layer and a Sm(Fe-Co)12-B layer, and the thickness of the Sm(Fe-Co)12-B layer was varied. From the result of XRD patterns measured in an out-of-plane configuration, peaks from ( 002) and ( 004) of the ThMn12-type crystal structure were observed for all samples. The intensity of these peaks was reduced by decreasing the thickness of the Sm(Fe-Co)12-B layer; however, it was recovered by introducing a Sm seed layer. Although the coercivity was decreased due to the reduction in the thickness of the Sm(Fe-Co)12-B layer, a large coercivity of 1.87 T was obtained in an Al-diffused thin film, which was thinned to 50 nm while introducing a Sm seed layer.