There currently exists many optoelectronic methods of characterization of microstructures. We present here a dynamic method which uses the principle of the optical vibrometer in order to determine the oscillatory modes of microstructures. This measurement makes it possible to go up with the mechanical properties. It is a method without contact, based on the lighting of a microstructure using a laser beam guided by a lensed tapered optical fiber which will be used. Principal evolution of this technique is its miniaturization. It allows to integrate the device within a cryostat, where we will be able to carry out measurements with a control of temperature, pressure and composition of the atmosphere.
A method of characterization without contact of passive microstructures is presented in this paper. Samples of different SiO2-Au microcantilevers (lengths from 100μm to 300μm, width 40μm, thickness 1.1μm) were studied by means of a Michelson interferometer. Two measurement techniques were employed, one by impulse response and the other by synchronous detection, in order to obtain the microcantilevers Eigen resonant spectrum and thus to determine their first three resonant frequencies. The knowledge of these frequencies makes possible the determination of the Young’s modulus of material and thus simplifies the modeling of the microsystem.