Novel technique for detecting the open fault using electroplating

This paper demonstrates a new technique for accurately isolating open-fault locations in via chain structures using copper (Cu) electroplating. Free copper ions can gain the required electrons from the sample surface so that the free copper ions can undergo reduction to form solid copper on the sample surface. From experiments, the interface between the electroplated and non-electroplated surface accurately indicates the open-fault location. The electroplated sample is then inspected using a focused ion beam (FIB). This technique, the electroplating localization method (EPLM), can process several samples at the same time or can process the entire wafer without cutting up the wafer.