Ultrahigh Purity Copper Alloy Target Used Innanoscale ULSI Interconnects

Abstract:

Current ULSI circuits have features with dimensions in the nanoscale region. As the critical dimension shrinks, Cu BEOL systems face reliability impacts. Alloying has been proved to be a promising technique to retard grain boundary electro-migration (EM). In this paper, dilute Cu Alloys such as Cu-Al, Cu-Mn for dual-damascene interconnect applications have been investigated. The alloy chosen principle for nanoscale interconnects has been discussed. The ultrahigh purity copper alloy target properties including purity, alloy composition, grain size and sputtering performance were investigated, to lay the foundation for the application of the large-size ultrahigh purity copper alloy target used for 300mm wafer fabrication. The relationships between deposited film behaviors and sputtering target properties in some applications were also discussed. In order to acquire high quality thin film, the properties of sputtering target such as alloy composition homogeneity, grain size and uniformity et al. have to be well controlled by proper fabrication techniques.

• Periodical: Materials Science Forum (Volume 815)
• Pages: 22-29
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.815.22
• Online since: March 2015
• Authors: Hao Zeng, Chao Lv, Yan Gao, Ting Yi Dong, Yong Hui Wang, Xing Quan Wang
• Keywords: Nanoscale ULSI Interconnects, Ultra High Purity Copper Alloy Target

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