Texture development and anomalous grain growth in Sb-doped MnPt 3 thin films by solid-state reaction of multilayered films

Abstract

Antimony-doped MnPt 3 thin films have been successfully fabricated by solid-state reaction of thin multilayered Mn/Sb/Pt films. It was found that the (100) preferential orientation of the MnPt 3 phase was developed with increasing antimony content. In addition to this, an anomalous crystalline growth with (100) oriented grains was observed, which resulted in a wide distribution of the grain size of the annealed samples. This behavior is considered to be secondary grain growth, which is usually caused by a surface free energy minimization rule. However, the (100) planes of MnPt 3 do not have the lowest surface free energy. We discuss the mechanism of this anomalous grain growth from the view-point of strain energy minimization, in conjunction with the anisotropy in the strain energy density for each crystallographic plane of MnPt 3.