Failure Analysis

This chapter discusses microstructure changes with or without lattice shift. It presents a unified model of mean-time-to-failure, on the basis of entropy production, which can be applied to the failure analysis of electromigration, thermomigration, stress-migration, as well as any other irreversible processes. Failure distribution is needed in statistical analysis in order to predict and to project the lifetime of a product. Phase change in traditional thermodynamics occurs in a closed system between two equilibrium states, usually under the condition of constant temperature and constant pressure. In mobile technology, the continuing demand for smaller size, more functionality, lower power consumption, and reduced cost is challenging in manufacturing, as well as in failure analysis. Thermal-crosstalk-induced thermomigration failure in unpowered microbumps has been found in 2.5D integration of circuit's devices. The chapter also presents several examples of system-level failure study in recent 2.5D integrated circuit devices.