L10 FePt(111)/glassy CoFeTaB bilayered structure for patterned media

We report on the use of CoFeTaB metallic glass thin film as a soft magnetic underlayer which promotes the growth of L1(0) FePt along the preferred (111) crystallographic direction. The preferred oriented phase of L1(0) FePt is obtained by either in situ deposition upon a heated CoFeTaB/SiO2/Si or at room temperature (FePt/CoFeTaB/SiO2/Si) followed by annealing at 400-450 degrees C for 15 min. The latter process is shown to be advantageous in terms of the fabrication of patterned media. Pattern sizes ranging from 25-100 nm made from L1(0) FePt (111)/glassy CoFeTaB were fabricated by photo/electron beam lithography. The structural and magnetic characterizations strongly suggest the applicability of the present bilayered structure in the fabrication of high density bit-patterned magnetic recording media. (C) 2011 American Institute of Physics. [doi:10.1063/1.3561803]