A new class of micro-electro-mechanical systems (MEMS) for material characterization is presented. These multilayered structures are lateral resonators which allow the determination of material properties of the different materials making up the system. Of particular significance is the ability to characterize many new materials previously untestable by resonant techniques. The basic lateral resonant structures are made of a single material, usually doped polycrystalline silicon, with beams anchored to the substrate at one end and supporting a rigid mass at the other. The rigid mass has a comb-shaped region on each side for electrostatically actuating and sensing the motion. The use of this electrostatic comb drive requires that the structure be made of a material that is electrically conductive. Thus, the class of materials which is amenable to characterization by resonance techniques has been somewhat limited. Multilayer structures, tested in conjunction with these basic monolithic structures, permit properties of both the base material and the subsequent layers to be determined. Stiffness and mass density of many new materials can be obtained by comparing the behavior of multilayer structures with their single-layer counterparts. Experimental designs and the associated analytical techniques for obtaining various properties are presented.
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