Ultrathin Ru-Ta-C Barriers for Cu Metallization

作者：Fang J S^*; Lin J H; Chen B Y; Chin T S

来源：Journal of the Electrochemical Society, 2011, 158(2): H97-H102.

DOI：10.1149/1.3518411

The use of an ultrathin Ru-Ta-C film as a barrier for copper metallization in sub-32-nm ultra-large-scale integration (ULSI) has been evaluated. The films, fixed at 5 nm, were deposited by magnetron sputtering using Ru and TaC targets, and the film composition and structure were adjusted by tuning the respective deposition power. The structure of the Ru-Ta-C films gradually changed from Ru(4)Ta(C) to nanocrystalline or nearly amorphous when optimizing TaC. For a sandwiched scheme of Cu/Ru(82)Ta(12)C(5)/Si or Cu/Ru(77)Ta(15)C(7)/Si, the failure temperature was at least 750 degrees C. We also electroplated Cu directly onto a Ru-Ta-C film without Cu seeding. Because of their low resistivity (< 100 mu Omega cm) and high thermal stability, Ru-Ta-C films are promising as a Cu barrier.

• 出版日期2011
• 单位清华大学