Non-destructive optical system based on digital holographic microscope for quasi real-time characterization of micromechanical shunt switch

A digital holographic microscope (DHM) is employed as non-invasive metrological tool for inspection and characterization of a micromechanical shunt switches in coplanar waveguide configuration (CPW) for microwave applications. The switch is based on a bridge that can be actuated by using electrodes positioned laterally with respect to the central conductor of the CPW. The DHM features, such as speed, contact-less and non-destructivity, have allowed a full characterization of an electrical actuated shunt switches. In particular, the out-of-plane deformation of the bridge due to the applied voltage has been investigated with high accuracy. DHM inspection allows to investigate the shape of the bridge during the actuation, the total warpage due to the actuation, possible residual gap, possible hysteresis, and so on. These characterizations have been carried out both in static and in dynamic condition. In full paper the complete characterization will be reported together with an accurate description of the optical system employed for the investigation.