Common Failure Modes in PWBs
SEM Lab, Inc. supports printed wiring board failure analysis and construction analysis. This presentation documents some of the most common failure causes seen in this laboratory. These include Hi-Pot failures, lamination failures, inner layer separation, corrosion failures, PTH Cu-plating failures, and conductive anodic filament failures. These failures can be mitigated to a significant degree by utilizing construction analysis to verify PWB quality. Construction analysis allows assessment of conductor layer thickness, dielectric layer thickness, PTH copper thickness, layer-to-layer registration, standard via & micro-via quality, PTH fill quality, and drilled-hole quality to name a few critical feature attributes.