The performance of a novel type of NdFeB micromagnets fabricated by agglomerationof magnetic powder by atomic layer deposition is investigated. The ALD-bondedmicromagnets can withstand standard BEOL (back-end of line) processing and heattreatments at temperatures of up to 400 °C in air and vacuum withoutany significant impact on the demagnetization curves. By optimized packingdensity a remanence of 660 mT is realized for the micromagnets. The coercivityµ0Hc = 890 mT remains constant forall samples and corresponds to the powder value.
A comparison of the demagnetizing behavior of micromagnets with theory of solidbody magnets prove that the influence of particle shape and hollow spaces ondemagnetizing field is low. Hence, a similar impact of shape on stray field andforces as for solid body magnets can be assumed when integrating NdFeBALD-bonded micromagnets in applications.
