Solid-state synthesis, structural and magnetic properties of CoPd films

Abstract

The results of the investigation of the structural and magnetic properties of CoPd films with equi atomic composition have been presented. The films have been synthesized by vacuum annealing of polycrys talline Pd/Co and epitaxial Pd/α Co(110) and Pd/β Co(001) bilayer samples. It has been shown that, for all samples, the annealing to 400°C does not lead to the mixing of layers and the formation of compounds. A fur ther increase in the annealing temperature results in the formation of a disordered CoPd phase at the Pd/Co interface, which is fully completed after annealing at 650°C. The epitaxial relationships between the disor dered CoPd phase and the MgO (001) substrate are determined as follows: CoPd(110)〈 〉 || MgO(001)〈100〉 and CoPd(001)[100] || MgO (001)[100], which are formed in the Pd/α Co(110) and Pd/β Co(001) films, respectively. According to the calculations, the first magnetocrystalline anisotropy constants of the disordered CoPd phase for Pd/α Co(110) and Pd/β Co(001) samples have close values:= -(1.6 ± 0.4) × 10 5 erg/cm 3 . A possible mechanism of the solid state synthesis of the CoPd alloy is proposed.