μ-XRF is a non-destructive analytical technique which can inspect defects, even non-visible ones, inside a sample because of the high penetration of X-rays. This application note introduces failure analysis to detect ion migration, voids, and foreign matter on electronics using the XGT-9000, with key features of the vertical irradiation of a 10 μm probe and the simultaneous imaging of fluorescent X-rays and transmission X-rays.