Polycrystalline silicon (polysilicon) is widely used as a mechanical layer in MicroElectroMechanical Systems (MEMS). Mechanical elements within MEMS structures are, by design, microscopic in size. Because the thickness of the polysilicon layer is typically around 2 micrometers and the width and length of the freed area is a few to hundreds of micrometers, standard techniques and apparatus for measurements of mechanical properties are not applicable. Furthermore, the deposition techniques for polysilicon cannot be adapted to make specimens big enough to test by conventional techniques. Therefore, special structures were designed to facilitate measurements of Young's modulus and fracture strength: cantilever beams and dog-bone tensile specimens. Here we report first experiences with these structures. These experiences include successes and failures in manipulating and testing the special structures. While no definitive results for either fracture strength or Young's modulus are reported here, some plausible values for both quantities were obtained. Test methods and preliminary results to date are discussed.
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