The interconnect metallization being used by the semiconductor industry has been aluminum or aluminum silicon. Aluminum silicon is being replaced by aluminum copper and aluminum copper silicon, due to its superior resistance to electromigration and hillock growth. This paper discusses the implementation of aluminum copper/silicon alloys in semiconductor processing, along with a review of the problems and advantages of the same.
Gadepally, Kamesh V. and Hawk, Roger M.
"Integrated Circuits Interconnect Metallization for the Submicron Age,"
Journal of the Arkansas Academy of Science: Vol. 43, Article 9.
Available at: https://scholarworks.uark.edu/jaas/vol43/iss1/9