Microscale mechanics for sensors and actuators

Microscale mechanical structures have been conceived and fabricated that make possible a wide variety of microsensors and microdynamical moving elements. Miniature sensors and microscopic moving elements on a chip are made by standard integrated-circuit fabrication techniques, augmented with special etches and deposited films. An integrated audio microphone, a miniaturized hot-wire anemometer for sensing gas flow, and an ultrasonic oscillator multisensor are some realized possibilities. Photolithographically shaped polysilicon layers, grown on an easily-etched sacrificial phosphosilicate glass layer, form tiny movable gears, sliders, springs, and cranks. Electrostatically driven micromotors less than 100 mu m across have been operated successfully. Device opportunities and fundamental properties requiring investigation are described.<
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