TbCo/Cr Amorphous Film with Perpendicular Magneto-Anisotropy

摘要

The amorphous TbCo/Cr films with perpendicular magneto-anisotropy were prepared by nonbiased r.f magnetron sputtering and the effects of Cr underlayer on the magnetic properties of TbCo films were investigated. It is found that both the TbCo layer thickness and the Cr underlayer can influence the magnitude of anisotropy for TbCo films. A perpendicular anisotropy as high as 4.57×106 erg·cm-3 was obtained in 120 nm thick Tb31C69 films with a 180 nm thick Cr underlayer. But it is only 3.24×106 erg·cm-3 for the Tb31Co69 film without Cr underlayer of the same thickness. The cross-sectional SEM observations indicate that the TbCo films with Cr underlayer consist of columns structure. It is considered that this heterogeneous structure gives rise to the anisotropy enhancement of TbCo films in case with Cr underlayer.