Small-area in-situ MEMS test structure to measure fracture strength by electrostatic probing

We have designed, fabricated, tested and modeled a first generation small area test structure for MEMS fracture studies by electrostatic rather than mechanical probing. Because of its small area, this device has potential applications as a lot monitor of strength of fatigue of the MEMS structural material. By matching deflection versus applied voltage data to a 3D model of the test structure, we develop high confidence that the local stresses achieved in the gage section are greater than 1 GPa. Brittle failure of the polycrystalline silicon was observed.

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