Magnetic Properties of Ultrathin TbFeCo Magnetic Films With Perpendicular Magnetic Anisotropy

In this study, we report on the experimental results of ultrathin TbFeCo films fabrications. The effects of annealing conditions on the magnetic characteristics of ultrathin TbFeCo magnetic films with various under- and capping-layers were explored. The effects of using SiNx, Al and Ti as capping- and under-layers are also investigated. We found that in contrast to the flat surface of SiN, the rugged interfaces induced by Al and Ti layers are beneficial in enhancing the perpendicular magnetic anisotropy for ultrathin TbFeCo films with thickness down to 3 nm. The STEM line scan shows the strong diffusion of Al atoms into TbFeCo layers. Annealing treatment can be used for control of coercivity from 85 Oe to 1 kOe.