Shrinking design rules and the introduction of new materials and processes in the formation of Cu interconnects in damascene modules have given rise to new and previously unknown killer defect mechanisms. These failure mechanisms are very challenging to detect, identify, and eliminate. The ability to characterize buried defects, such as defective vias, previous layer defects, or integration issues detected by optical defect inspection tools as well as electron-beam inspection tools has become mandatory. Out of the several cross-section tools available to the lab, the one that best addresses the in-line applications requirements is known as the DualBeam (FIB/SEM). The ion beam allows cross-sectioning while a coincident electron beam allows for high resolution imaging of the cross-section. Using the FEI Defect Analyzer 300 DualBeam system, this process has been automated for in-line usage. Defects can be navigated to using defect files generated by the inspection tools. The wafer production line is now enabled to easily mill cross sections in-line and determine root causes, something that is often not possible from top down information alone. For volume in-line use on defects, additional requirements must also be met: compatibility with clean room environment, navigation on full wafers to relocate the defects detected by the inspection tools, throughput, ease of use, low impact on wafers so that they can be returned to the line. All of this must allow the gathering of data at numerous cross-sections on buried defects in order to perform the same type of Pareto analysis as is traditionally done after defect review of top-down visible defects. Example use cases will be presented to demonstrate how this methodology is being developed in a manufacturing environment to help understand previously unexplained yield losses and to deliver results with a rapid response time. Applications on defects detected with electron beam inspection in copper or tungsten interconnects, will be described. The interest of such a methodology on more traditional defects after optical inspection will also be stressed.