Title :
A robust 45 nm-node, dual damascene interconnects with high quality cu/barrier interface by a novel oxygen absorption process
Author :
Abe, M. ; Tada, M. ; Ohtake, H. ; Furutake, N. ; Narihiro, M. ; Arai, K. ; Takeuchi, T. ; Saito, S. ; Taiji, T. ; Motoyama, K. ; Kasama, Y. ; Arita, K. ; Ito, F. ; Yamamoto, H. ; Tagami, M. ; Tonegawa, T. ; Tsuchiya, Y. ; Fujii, K. ; Oda, N. ; Sekine, M.
Author_Institution :
NEC Corp., Kanagawa
Abstract :
By a novel oxygen absorption process, low oxygen-content Cu-alloy is implemented for fully-scaled-down, 45 nm-node dual damascene interconnects (DDIs) with 140 nm-pitched lines and 70 nmOslash-vias. In this process, a very thin metal film as an oxygen absorber, which has larger negative change in the standard Gibbs free energy of oxidation than a barrier metal, is put on a natural oxide at a surface of electro-plated, Cu film. The oxygen atoms diffuse to the oxygen absorber, not to the barrier metal under the Cu film, achieving high quality Cu/barrier interface after annealing. Combining the oxygen absorption process with Cu-alloy process, 45 nm-node DDI in molecular-pore-stacking (MPS) SiOCH film is successfully obtained with high endurances for SIV, EM and TDDB
Keywords :
copper alloys; integrated circuit interconnections; integrated circuit metallisation; integrated circuit reliability; silicon compounds; 140 nm; 45 nm; Cu; Gibbs free energy; SiOCH; annealing; barrier metal; dual damascene interconnects; electroplated film; molecular pore stacking; oxidation; oxygen absorber; oxygen absorption process; thin metal film; Absorption; Annealing; Etching; Indium tin oxide; Metallization; National electric code; Oxidation; Oxygen; Robustness; Silicon compounds;
Conference_Titel :
Electron Devices Meeting, 2005. IEDM Technical Digest. IEEE International
Conference_Location :
Washington, DC
Print_ISBN :
0-7803-9268-X
DOI :
10.1109/IEDM.2005.1609271
