Anisotropic Nd-Fe-B Sputtered Thin Film Magnets

Sputtering conditions for synthesis of anisotropic Nd-Fe-B thin film magnets were studied. The results show that both the film composition and the substrate temperature are important parameters affecting the c-axis orientation of the Nd-Fe-B tetragonal compounds. It was shown that an anisotropic thin film magnet with its easy axis of magnetization normal to the film plane could be grown by choosing a composition near Nd13Fe70B17 at a substrate temperature as low as 460°C, considerably below the previously reported lowest value. The anisotropic thin film magnet exhibited an intrinsic coercivity of 7 kOe and a maximum, energy product of 20 MGOe. The possibility of application of such thin film magnets to microactuators and motors was demonstrated by the fabrication and operation of a pulse motor 5 mm in diameter, based on the anisotropic thin film magnet prepared in this work.