Overlayer-induced anisotropic alignment of Nd2Fe14B nanograins

Highly anisotropic Nd2Fe14B thin film has been produced by triggering crystallization of sputter-deposited amorphous Nd-Fe-B layer by deposition of crystalline Cr overlayer. A downward growth of strongly textured Nd2Fe14B columnar grains was observed, starting from the interface between the Nd-Fe-B amorphous layer and the Cr overlayer. Cross-sectional transmission electron microscope observation results suggest that the possible mechanism of this peculiar crystallization is the heterogeneous nucleation at the surface of Nd-Fe-B amorphous layer, triggered by the crystalline Cr overlayer. (C) 2001 American Institute of Physics.