Defect analysis using high throughput plasma FIB in packaging reliability investigations

Within this paper the application potential of a new fast Plasma FIB system for defect analysis regarding packaging reliability studies is evaluated. Depending on the material under investigation both the higher current and the higher sputter efficiency of the Xe significantly improve the range of application fields and/or the analysis throughput. This makes the Plasma FIB a very attractive tool for the analysis of relatively large interconnect structures without any need of mechanical preparation steps. We used the Plasma FIB to support reliability investigations for automotive and power electronics using heavy wire Aluminum bonded interconnects, die attach materials like Direct Copper Bonded Substrates (DCB) and lead-free soldered contacts. For all of these application cases specifically adapted preparation strategies have been investigated and applied to remove polishing artifacts by stepwise tilting the sample. It is demonstrated that Plasma-FIB milling significantly increases the efficiency and throughput and offers new approaches and more flexibility in sample preparation. Within the paper selected case studies regarding reliability investigations and failure analysis are presented. In addition, an assessment of the analysis throughput increase, of new extended application ranges and current limitations will be given.