Giant magnetostrictive thin film materials and applications

Sputter-deposited magnetostrictive films present a new and interesting approach to realizing cantilever- and membrane-type actuators or resonant sensors in microsystems as they offer features like contactless, high frequency operation, simple actuator designs and a cost-effective manufacturing technique. An essential development was the preparation of low field positive and negative giant magnetostrictive amorphous, or multilayered thin film materials with magnetostriction exceeding 300 ppm at 0.02 T. Using these optimized films, Si-based microsystems (micropump, linear ultrasonic motor) have been realized which demonstrate the potential of magnetostrictive thin film actuators. (C) 1997 Elsevier Science S.A.