Generation of Motion in Microstructures using the Reflection of Pulse Elastic Waves.

Abstract

This paper proposes a novel technique for the dynamic characterization of microstructures by generating motion in them. Here, microstructures refer to microsensors and microfabricated mechanical components. The method satisfies the requirements for the dynamic characterization of microstructures. Motion is triggered by the reflection of pulse elastic waves propagating in a metal bar. The microstructure to be characterized is fixed to the end surface of the bar and dynamic displacement generated is measured by an argon-ion-laser-based interferometer. The motion of the end surface of the bar generated by the reflection of a pulse elastic wave is measured by either strain gages bonded on the side of the bar or directly by the argon-ion-laser-based interferometer. There is a simple mathematical relationship between the measured strain and the acceleration at the end of the bar. The validity is verfied by the characterization of several kinds of microstructures : a silicon doubly supported beam, an accelerometer and an AE-transducer.