Figure 4904 shows the overlay images of optical images (grey) and actual LIT images (in color) of a faulty device, taken at a lock-in frequency of 10 Hz using a 2.5 X objective and allowing the display of the whole die. One of the point-like thermal signals was identified as defect-related thermal emission by comparing the heat dissipation of the defective device to a reference. The localization of the fault allowed a FIB preparation of a cross-section specimen for a scanning electron microscopy (SEM) investigation. The SEM image in Figure 4904 (d) shows a residue of a TiN barrier layer which were not completely etched away (denoted by a red arrow) leading to a short.

[1] Paiboon Tangyunyong and Christian Schmidt, Thermal Defect Detection Techniques, Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.