Effects of substrate temperature and annealing treatment on the micro-structure and magnetic characteristics of TbDyFe films

A series of TbDyFe films were prepared by DC magnetron sputtering. The effects of substrate temperature and annealing temperature on the phase structure and the magnetic properties of the sample films were investigated. The annealing treatment has a significant influence on the microstructure and the magnetic properties of the sample. The results obtained by XRD indicate that the films deposited at a temperature lower than 525°C are amorphous and have an easy magnetization direction perpendicular to the film plane. An RFe2 phase is formed in the sample annealed at 550°C and the residual phases observed are Fe and rare earth oxide. The magnetic properties Hc and Ml/MS of the film annealed at 550°C obtain the maximum values, for which the formation of the RFe2 phase is mainly responsible. An annealing treatment leads to a rotation of the sample's easy axis from being parallel to the film surface to becoming vertical.