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High performance hard magnetic NdFeB thick films for integration into Micro-Electro-Mechanical-Systems

N. M. Dempsey·Arnaud Walther·Frederic May·Dominique Givord·Kirill Khlopkov·Oliver Gutfleisch
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Abstract

5$μ$m thick NdFeB films have been sputtered onto 100 mm Si substrates using high rate sputtering (18 $μ$m/h). Films were deposited at ≤ 500 C and then annealed at 750 C for 10 minutes. While films deposited at temperatures up to 450 C have equiaxed grains, the size of which decreases with increasing deposition temperature, the films deposited at 500 C have columnar grains. The out-of-plane remanent magnetization increases with deposition temperature, reaching a maximum value of 1.4 T, while the coercivity remains constant at about 1.6 T. The maximum energy product achieved (400 kJ/m3) is comparable to that of high-quality NdFeB sintered magnets.

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N. M. Dempsey, Arnaud Walther, Frederic May, Dominique Givord, Kirill Khlopkov, Oliver Gutfleisch. 2007-03-29. High performance hard magnetic NdFeB thick films for integration into Micro-Electro-Mechanical-Systems. https://doi.org/10.1063/1.2710771

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