Determination of maximum allowable strain for polysilicon micro-devices

Abstract Polycrystalline silicon (polysilicon) is a material commonly used for micro-electro-mechanical systems (MEMS) for which reliable mechanical properties data is not available, especially for devices that have dimensions on the order of microns. This paper proposes a method for using test data that accounts for the uncertainties in mechanical properties and presents data from tests of polysilicon that may be used in the future design of polysilicon MEMS. The testing of 161 micro-devices to failure, results in a recommendation for design that the nominal strain be maintained below 0.0055. 1998 Elsevier Science Ltd. All rights reserved.

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