Advanced Analysis and Monitoring of Failure Mechanisms in Microelectronics Metallization

Metallization structures in microelectronic systems undergo various degradation processes. They can be caused by diffusion mechanisms induced by electrical current only or by electrical current in combination with different boundary conditions like parallel thermo-mechanical strains or specific loading cycles in the currents itself. Beyond that, solely thermo-mechanical strain cycles can lead to a fatigue-based degradation of the microelectronics metallization. All those mechanisms can lead to a degradation in performance and ultimately to failures in the microelectronic systems. To physically understand these degradation processes, to formulate appropriate lifetime models, and to mitigate degradation with more robust designs, the failure mechanisms need to be studied in detail. Most crucial to that is an advanced actuation, analysis and monitoring of the development of the failure peculiarities over time using novel and improved accelerated testing procedures. For example, a novel setup for low frequency pulsed-current electromigration (EM) testing will be shown in conjunction with the needed advanced PFA methods. There, the non-equilibrium Joule-heating thermal fields lead to a degradation behavior different to the one expected by just the current duty cycles.