Micromachined magnetic actuators using electroplated Permalloy

Results on design, fabrication, and testing of silicon micromachined magnetic actuators are presented. Electroplated, low-stress Permalloy (Ni/sub 80/Fe/sub 20/) material is the medium for magnetic interaction and force generation. The Permalloy piece is supported by a structural plate, which consists of polycrystalline silicon thin film prepared by low-pressure chemical vapor deposition (LPCVD). Magnetic actuators supported both by cantilever beams and by torsional beams can provide large force (on the order of 100 /spl mu/N) and large displacement (on the order of 100 /spl mu/m). The vertical loading force of magnetic actuators under external bias has been experimentally determined. Applications of such actuators in magnetically assisted levitation and parallel assembly of three-dimensional structures are demonstrated.