Fast Laser Scanning Imaging System for Surface Displacement Measurements

We present a scanning imaging system using galvanometric mirrors coupled to a heterodyne interferometric probe. This setup is dedicated to the off-plane surface displacement imaging, in particular for microelectronic devices. The use of galvanometric mirrors coupled to the heterodyne probe makes it a sensitive and fast measurement system. We present results on a microelectronic device, and we compare the performances of this system with point and CCD interferometry imaging setups.