Perpendicular magnetic anisotropy in NdFeB thin films

The perpendicular magnetic anisotropy (PMA) in NdFeB thin films is investigated. PMA was observed when the c axis of Nd2Fe14B phase orients perpendicular to the film plane. The c-axis orientation and hence the PMA was found to be very sensitive to composition and substrate temperature. The change of composition or substrate temperature leads to a deterioration in the c-axis orientation and PMA. However, the other parameters such as sputter power or deposition rate do not play a very important role over a wide range used in this study. Increasing the thickness of films does not cause a great deterioration of PMA up to 1500 nm, although the trend indicates that at higher values of thickness the films become isotropic. (C) 1999 American Institute of Physics. [S0021-8979(99)46908-7].