|Microfabrication and process integration of powder-based permanent magnets
|Year of Publication
|Bowers, B., O. D. Oniku, and D. P. Arnold
|Technologies for Future Micro-Nano Manufacturing
|Magnetics, Microfabrication, Micromagnets, Powders
This article presents a summary of recently developed powder-based permanent magnet microfabrication methods. Magnets are fabricated with a dry-pressing method using three different types of isotropic magnetic powders: 50 μm Nd–Fe–B, 5μm Nd–Fe–B, and 1 μm barium ferrite powder. The magnets are shown to exhibit intrinsic coercivities (Hci) as high as 720kA/m, remanences (Br) up to 0.5 T, and maximum energy products (BHmax) up to 20 kJ/m3, depending on the magnetic powder used. Process compatibility experiments also demonstrate the potential for the magnets to withstand typical microfabrication chemical exposure and thermal cycles, thereby facilitating their integration into more complex process flows. The remanent magnetization of the magnets are also characterized at elevated temperatures to determine their temperature dependence.