Applications of dynamic techniques for accurate determination of silicon nitride Young's moduli

Abstract

Reports on the characterization of higher resonant modes of microcantilevers made of silicon nitride thin film. An optical technique (a Fabry-Perot interferometer with optical beam deflection technique combination) has been used to measure resonant frequencies, normal displacement and angular deflections in order to characterize mode vibrations. From the measurement of higher flexural mode resonant frequencies of one microcantilever, the mechanical properties such as Young's modulus and stiffness are determined. In comparison to other methods using many cantilevers of different lengths, our method allows the errors due to measurement of cantilever dimensions to be avoided. This method leads to accurate estimation of Si/sub 3/N/sub 4/ Young's modulus of 194.2 GPa.