Perpendicular magnetic anisotropy in NdFeB thin films

The perpendicular magnetic anisotropy (PMA) in NdFeB thin films is investig ated. PMA was observed when the c axis of Nd2Fe14B phase orients perpendicu lar to the film plane. The c-axis orientation and hence the PMA was found t o be very sensitive to composition and substrate temperature. The change of composition or substrate temperature leads to a deterioration in the c-axi s 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 de terioration of PMA up to 1500 nm, although the trend indicates that at high er values of thickness the films become isotropic. (C) 1999 American Instit ute of Physics. [S0021-8979(99)46908-7].