Fast characterization of silicon membrane structures by laser-doppler vibrometry

Micromechanical structures were investigated nondestructively via laser-Doppler-vibrometry to determine defect structures. Silicon membrane structures were characterized by their measured resonant frequencies and mode shapes. The influence of defects on the micromechanical structures on the measured dynamic properties is shown. Defective samples were indentified on the basis of the ratios of measured resonant frequencies and the quantified comparison of mode shapes without an identification of unknown parameters. The investigations showed that a fast determination of defect structures is possible by measuring dynamic properties.