Magnetic Properties and Crystal Structure Analysis of Ferromagnetic Metal / r-plane Oriented Cr₂O₃ Multilayer

Abstract

We report the crystal structures and magnetic properties of [Pt/Co]₃/Pt/r-oriented Cr₂O₃ multilayers fabricated by DC-RF magnetron sputtering method. From the results of 2θ-θ x-ray diffraction profile, highly r-plane (1102) oriented Cr₂O₃ film grows. Preferable orientation of Pt and Co films is (111). The lattice spacing of r-plane Cr₂O₃ was 0.363 nm. This value is in agreement with that of the bulk, indicating that the film is grown without stress from the substrate. From the reciprocal space mapping, both the substrate and film peaks were visible for (22010) plane, while no peaks were observed for the (2208) plane. The magnetic property of the multilayer is investigated by magnetic field (H) dependences of the magnetizations (M). The exchange bias filed, H_EB, was -150Oe at 5K, which is the first observation using highly ordered r-plane Cr₂O₃ film.