Mechanical failure prediction of copper/low-k dielectric interconnects using cohesive zone modeling

Due to the miniaturization of integrated circuits (ICs), the IC thermo-mechanical reliability becomes more and more critical as design criterion. Finite element tools can assists IC developers to meet this challenge. This paper considers the mechanical failure mode where different layers of the interconnect structure delaminate. The interface cracks grow with the high crack speeds associated with brittle fracture behavior. An interface damage mechanics approach is employed. The research objective is to overcome the numerical difficulties of this approach when used for brittle fracture. A simplified problem illustrates to what extent this goal has already been achieved and it shows which aspects of the solution procedure need more attention.