Magnetic microactuation of polysilicon flexure structures

A microactuator technology that combines magnetic thin films with polysilicon flexural structures is described. Devices are constructed in a batch-fabrication process that combines electroplating with conventional lithography, materials, and equipment. A microactuator consisting of a 400/spl times/(47-40)/spl times/7 /spl mu/m/sup 3/ rectangular plate of NiFe attached to a 400/spl times/(0.9-1.4)/spl times/2.25 /spl mu/m/sup 3/ polysilicon cantilever beam has been displaced over 1.2 mm, rotated over 180/spl deg/, and actuated with over 0.185 nNm of torque. The microactuator is capable of motion both in and out of the wafer plane and has been operated in a conductive fluid environment. Theoretical expressions for the displacement and torque are developed and compared to experimental results.