Electromagnetic microactuators with on-chip resin-bonded permanent magnets

In this work we present modeling, fabrication and characterization of novel electromagnetic microactuators with integrated resin-bonded hard magnets embedded in the handle of silicon-on-insulator (SOI) wafers. Trenches etched through the handle of the SOI wafers are filled with the resin-bonded magnet material and allowed to cure at ambient temperature. Clamped-clamped beams fabricated from the single crystal silicon device layer of the SOI wafer are fabricated above the resin-bonded magnet filled trenches. Applying alternating current through the beam produces steady out-of-plane displacements due to resistive Joule heating and excites in-plane resonant vibrations due to Lorentz force coupling. The 8 mm long, 32 μm wide beams produced a maximum in-plane amplitude of 4.2 μm under an applied 2.4 mA current while the resonant frequency was tuned by changing the current amplitude. The results provided by the coupled thermo-electro-mechanical model of the beam and backed by experiments suggest that the integrated resin bonded magnets can be efficiently used for the actuation of micro structures.