MAGNETIC MICROACTUATION OF TORSIONAL POLYSILICON STRUCTURES

A microactuator technology utilizing magnetic thin films and polysilic on flexures in applied to torsional microstructures. These structures are constructed in a batch-fabrication process that combines electropl ating with conventional IC-lithography, materials, and equipment. A mi croactuated mirror made from a 430 mu m X 130 mu m X 15 mu m nickel-ir on plate attached to a pair of 400 mu m X 2.2 mu m X 2.2 mu m polysili con torsional beams has been rotated more than 90 degrees out of the p lane of the wafer and actuated with a torque greater than 3.0 nN m. Th e torsional flexure structure constrains motion to rotation about a si ngle axis, which can be an advantage for a number of microphonic appli cations (e.g., beam chopping, scanning, and steering).