Morphology and hard magnetic properties of epitaxial Nd-Fe-B films grown on Mo and Cr/Ta buffers

Epitaxial hard magnetic Nd-Fe-B films were deposited on a Mo buffer layer on MgO(100) substrates by pulsed laser deposition and compared with films on a combined Cr/Ta buffer layer. On Mo buffers, films grow relatively smooth and continuous compared to Cr/ Ta buffer, where the films posses a rough surface and granular. These differences in morphology are discussed with respect to lattice misfit and wettability, and they can explain the observed strong difference in coercivity. Despite the low coercivity the lower phase formation temperature and more continuous growth of Nd-Fe-B on Mo buffer may be of advantage for patterned media applications, which require smooth and continuous films. (c) 2007 American Institute of Physics.