Highly Reliable and Low Resistive Cu/Low-k Dual Damascene Interconnects by Using TaTi Barrier Metal

被引:1
作者
Motoyama, K. [1 ]
Fujii, K. [1 ]
机构
[1] Renesas Elect Corp, Proc Technol Div, Prod & Technol Unit, Sagamihara, Kanagawa 2525298, Japan
关键词
TAN DIFFUSION-BARRIERS; CU INTERCONNECTS; COPPER INTERCONNECTS; TI-BARRIER; RELIABILITY; LAYERS; ADHESION; LIFETIME; BEHAVIOR; FILM;
D O I
10.1149/2.016206jss
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Novel barrier metal of TaTi alloy has been developed for highly reliable Cu/low-k DD interconnects. TaTi barrier metal with higher Ti concentration improved EM performance, however, it showed both step coverage degradation and line resistance increase. Then, control of Ti diffusion amount from the barrier metal into Cu, determined by Ti concentration in the PVD target, was found to be a key to keep both low line resistance and high reliability. Limited Ti content in the TaTi of Ta-2wt% Ti showed good step coverage, adequate barrier property and better wettability to Cu than Ta. Furthermore, Ta-2wt% Ti achieved 10 times longer EM lifetime than Ta without penalty of line resistance. Thus, Ta-2wt% Ti is one of the promising candidates of barrier metal for highly reliable Cu/low-k interconnects without resistance increase in the future generations. (C) 2012 The Electrochemical Society. All rights reserved.
引用
收藏
页码:P279 / P284
页数:6
相关论文
共 39 条
[1]   Effects of Ti insertion between Cu and TiN layers on reliability in Cu/Ti/TiN/Ti layered damascene interconnects [J].
Abe, K ;
Onoda, H .
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B, 2003, 21 (03) :1161-1168
[2]   Effects of the metallurgical properties of upper Cu film on stress-induced voiding (SIV) in Cu dual-damasceinte interconnects [J].
Abe, M ;
Furutaike, N ;
Saito, S ;
Inoue, N ;
Hayashi, Y .
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS, 2005, 44 (4B) :2294-2302
[3]  
Baek WC, 2006, ADVANCED METALLIZATION CONFERENCE 2005 (AMC 2005), P457
[4]   Characterization of Ta and TaN diffusion barriers beneath Cu layers using picosecond ultrasonics [J].
Bryner, Juerg ;
Profunser, Dieter M. ;
Vollmann, Jacqueline ;
Mueller, Elisabeth ;
Dual, Juerg .
ULTRASONICS, 2006, 44 (e1269-e1275) :E1269-E1275
[5]   Diffusion barrier properties of amorphous and nanocrystalline Ta films for Cu interconnects [J].
Cao, Z. H. ;
Hu, K. ;
Meng, X. K. .
JOURNAL OF APPLIED PHYSICS, 2009, 106 (11)
[6]  
Chen Fang-fang, 2010, Proceedings 2010 Symposium on Photonics and Optoelectronics (SOPO 2010), DOI 10.1109/SOPO.2010.5504190
[7]   Addressing Cu/Low-k Dielectric TDDB-Reliability Challenges for Advanced CMOS Technologies [J].
Chen, Fen ;
Shinosky, Mike .
IEEE TRANSACTIONS ON ELECTRON DEVICES, 2009, 56 (01) :2-12
[8]  
Christiansen C., 2011, 2011 IEEE INT REL PH
[9]   Stress migration lifetime for Cu interconnects with CoWP-only cap [J].
Gambino, Jeffrey P. ;
Johnson, Christy L. ;
Therrien, Joseph E. ;
Hunt, Douglas B. ;
Wynne, Jean E. ;
Smith, Sean ;
Mongeon, Stephen A. ;
Pokrinchak, D. Philip ;
Levin, Theodore M. .
IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY, 2006, 6 (02) :197-202
[10]   Low resistive and highly reliable copper interconnects in combination of silicide-cap with Ti-barrier for 32 nm-node and beyond [J].
Hayashi, Y. ;
Matsunaga, N. ;
Wada, M. ;
Nakao, S. ;
Watanabe, K. ;
Sakata, A. ;
Shibata, H. .
PROCEEDINGS OF THE 2009 IEEE INTERNATIONAL INTERCONNECT TECHNOLOGY CONFERENCE, 2009, :252-254