Influence of pressure on (0 0 1)-preferred orientation and in-plane residual stress in rapidly annealed FePt thin films

Abstract

The dependence of annealing pressure and background pressure during film deposition on the in-plane residual tensile stress, the crystallographic orientation and the surface chemical state in single-layer FePt films formed with rapid thermal annealing were investigated. On manipulating the annealing pressure and background pressure, the transition from perpendicular magnetic anisotropy to isotropy was found in the rapidly annealed FePt films. The slight surface oxidation of the FePt films during rapid thermal annealing induced an in-plane tensile stress to develop the (0 0 1)-texture and a perpendicular magnetic anisotropy. In contrast, for FePt films prepared at low pressure, the accumulated in-plane tensile stress was insufficient to develop a well aligned (0 0 1)-texture because of a lack of stress induced by a surface oxidation layer.