Study on the impact of barrier metal deposition processes on W Via/CA ET high resistance by TEM failure analysis

In this work we reported ET (electrical testing) failure case studies related to the process drift of barrier metal deposition (BM) during W via/CA process loops. We presented detailed TEM failure analysis in order to understand the failure mechanism and root cause behind the high via/CA resistance. We demonstrated the importance of TEM characterization and identification of key physical failure signatures for the root-cause understanding of via/CA-level ET failure, and the correlation between physical failure signatures and inline investigation results is the ley for the root cause understanding.