The copper Damascene process is widely established and has brought higher performance to semiconductor devices. Copper has replaced aluminum because of its lower resistivity, higher reliability, and lower cost and was expected to be better because of its higher activation energy for diffusion. However, copper also suffers from electromigration (EM) and stress migration (SM) reliability issues (Fig. 30.1) as geometries continue to shrink, and current densities increase.
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Lee, B., Ivanov, I. (2009). Processes and Tools for Co Alloy Capping. In: Shacham-Diamand, Y., Osaka , T., Datta, M., Ohba, T. (eds) Advanced Nanoscale ULSI Interconnects: Fundamentals and Applications. Springer, New York, NY. https://doi.org/10.1007/978-0-387-95868-2_30
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