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An original experimental method is presented for measuring the stiffness and displacement characteristics of small size freestanding mechanical elements on actual MEMS devices. This setup allows, using analytic and finite-element method mechanical calculations, the extraction of the elastic modulus of the materials used in such mechanical elements, thus eliminating the need of special integrated test structures. The setup has, respectively, a force and displacement measurement accuracy better than 1 /spl mu/N and 50 nm. Its application is demonstrated by the characterization of a MEMS magnetostatic switch.

A passive magnetostatic sensing MEMS device, similar to a reed switch, having a packaged volume of 2 mm/sup 3/ is described. It is capable of sensing the field of a 1 mm/sup 3/ SmCo magnet at a distance of more than 2 mm. The contact force between the microformed rhodium contact surfaces lies between 10 and 30 /spl mu/N, and contact resistances as low as 2 /spl Omega/ are measured. No contact sticking is observed. The device operation life extends to at least 200,000 cycles when packaged at wafer level with epoxy sealing. The device operation life increases to 100/spl times/10/sup 6/ cycles when measured on bare wafers in argon, showing that these MEMS sensors are intrinsically reliable in spite of the very low contact forces.