A New Technique for Non-Invasive Short-Localisation in Thin Dielectric Layers by Electron Beam Absorbed Current (EBAC) Imaging

In this paper a novel approach for precise localisation of thin oxide breakdowns in transistor or capacitor structures by electron beam absorbed current (EBAC) imaging based on Scanning Electron Microscopy will be presented. The technique significantly improves sensitivity and lateral resolution of short localisation in comparison to standard techniques, e.g. Photoemission Microscopy, and provides direct defect navigation within a combined FIB/SEM system for further cross section analysis. The oxide short is minimal affected by electrical stimulation preserving its original defect structure for further physical root cause analysis. The feasibility of this new technique is demonstrated on a gate oxide (GOX) and two capacitor oxide (COX) breakdown failures.