Amorphous TbDyFe films show excellent soft-magnetic properties combined with giant magnetostriction. However, for technical applications the major drawback is the low Curie temperature which is typically around 400 K. To increase the Curie temperature and simultaneously achieve good soft-magnetic properties as well as giant magnetostriction the preparation of crystalline films with nanometer-sized grains is necessary. Terfenol-D-like films with additives of Zr, Nb, Mo were prepared by ion-beam sputtering and different heat treatments were applied to investigate the crystallization behaviour. These additives enhance the nucleation of REFe2 grains and hinder the formation of REFe_3 which is assumed to be responsible for high coercivity values. Furthermore, nanometer-scaled multilayers with Nb interlayers were prepared. This multilayer structure is suitable to inhibit grain growth and hence further decreases the average grain size. The resulting nanocrys-talline microstructure leads to small coercive fields and high Curie temperatures. In addition, protective layers were investigated in order to avoid oxidation during the heat treatments for crystallization. The results will be discussed with respect to possible applications in microsystem technology.
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