A study of stress voiding effect on AlSi metal bank allowed lifetime for IC foundry fabs

We introduce a mechanism for metal void formation that is due to an interfacial vacancy in the underlying dielectric. These voids will occur during a period of storage in a metal bank. An experiment was conducted to detect metal voids more easily and to evaluate a process-design modification to prevent the formation of these voids. For mask ROM products, this work has helped assure the reliability of metallized wafers stored for long periods of time.