Fabrication and properties of Nd(Tb,Dy)Co/Cr films with perpendicular magnetic anisotropy

Light rare earth-heavy rare earth-transition metal films (LRE-HRE-TM)have large saturation magnetization (M s) and are the promising media for hybrid recording. In this paper, Nd(Tb,Dy)Co/Cr films with perpendicular magnetic anisotropy were successfully fabricated onto glass substrate by RF magnetron sputtering and the effects of sputtering technology parameters and Nd substitution for HRE atoms on the magnetic properties were investigated. It was found that when the sputtering power and sputtering time are 250W and 4min, respectively, the magnetic properties of Nd(Tb,Dy)Co/Cr films obtain optimization, perpendicular coercivity, Ms and remanence square ratio(S) of NdTbCo/Cr film reach 3.8kOe, 247emu/cm 3 and 0.801, respectively. With the increasing of Nd concentration, Ms increases, while the coercivity (H c)and the temperature stability of magnetic properties decrease distinctly. These results can be explained by the ferri-magnetic structure of the RE-TM alloy. © 2009 Copyright SPIE - The International Society for Optical Engineering.