Uncovering the True Defect Behind an Ambiguous Distinct PEM Hotspot Through Micro-Probing and FIB Circuit Edit-PVC Analysis

In some cases, even though a distinct emission (EMMI) hotspot localized by a Photo Emission (PEM) tool and in-depth circuit analysis have established a correlation between the electrical failure, it does not guarantee that a defect will be found exactly at the EMMI site location during physical analysis. Supplementary fault localization techniques such as powered and static micro-probing complemented by circuit editing using Focused-Ion Beam (FIB) and Passive Voltage Contrast (PVC) analysis are necessary to uncover the true defect behind an ambiguous distinct PEM hotspot. Two case studies are presented in this paper to demonstrate how these supplementary techniques were exploited to successfully determine the failure mechanism and root cause.