Failure Analysis Techniques and Studies on Vertical Short Issue for Production Wafers

With the scaling down of semiconductor devices to the nanometer range, physical failure analysis (PFA) has become more challenging especially on short failures that involved metal layers vertically. In the past, we have reported a few vertically short failure analysis techniques on the product under new process development, and new technology node [1]. Vertical short in Back-End-of-Line (BEOL) on a new product, new process and technology underdevelopment is more frequent than a mature production device. In this paper, we will discuss failure analysis (FA) on different types of vertical short failures that happened in a production wafer.