Title :
Reliability improvement using buried capping layer in advanced interconnects
Author :
Yiang, K.Y. ; Mok, T.S. ; Yoo, W.J. ; Krishnamoorthy, Akshay
Author_Institution :
Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore
Abstract :
Electrical leakage and breakdown characteristics of low-dielectric constant (low-k) dielectrics are increasingly becoming major reliability issues as inter-metals spacings in interconnects are scaled towards the 0.1 μm technology node. These issues are greatly alleviated by the implementation of a buried capping layer (BCL) in Cu damascene structures. It is found that a BCL of 100 Å thickness in Cu/SiOC interdigitated comb structures reduces the leakage current by 1 order of magnitude and improves breakdown strength by a factor of 1.5 to 2. In addition, the BCL is able to suppress the formation of process-induced traps in the low-k dielectric. These findings can have important reliability considerations for Cu/low-k integration schemes.
Keywords :
copper; dielectric thin films; electric breakdown; integrated circuit interconnections; integrated circuit metallisation; integrated circuit reliability; leakage currents; permittivity; silicon compounds; 0.1 μm technology node; 0.1 micron; 100 Å; Cu damascene structures; Cu-SiOC; Cu/SiOC interdigitated comb structures; advanced interconnects; breakdown characteristics; buried capping layer; electrical leakage; inter-metals spacings; leakage current; low-dielectric constant dielectrics; reliability improvement; Artificial intelligence; Chemical vapor deposition; Dielectric breakdown; Dielectric constant; Dielectric materials; Electric breakdown; Etching; Leakage current; Materials reliability; Silicon carbide;
Conference_Titel :
Reliability Physics Symposium Proceedings, 2004. 42nd Annual. 2004 IEEE International
Print_ISBN :
0-7803-8315-X
DOI :
10.1109/RELPHY.2004.1315347
