MICRODYNAMICS

Microdynamics, the science, technology, and design of moving micromechanical devices and mechanisms, has become the focus for a widening scope of research. Microdynamic structures made with technology derived from IC processes show promise for the design of high-performance sensors and actuators and can be combined with on-chip circuits. This development may lead to a new class of microsystems having significant impact on engineering design. Polycrystalline silicon and silicon nitride can be applied as mechanical materials in a process in which microstructures are freed from the substrate by etching a sacrificial layer of silicon dioxide. This technology, first demonstrated as a means to produce electrostatically driven resonant bridges, has been extended to make rotating and sliding structures, gears, springs, and recently micromotors. Research on the mechanical properties of the electrical materials forming microdynamic structures (which previously had exclusively electrical uses), on the scaling of mechanical design, and on the effective uses of computer aids is needed to provide the engineering base that will make it possible to exploit fully this technology. © 1990.