Title :
Two-step copper electroplating technique using seed enhancement step with alkali-metal-free copper pyrophosphate bath
Author :
Hosoi, N. ; Kimizuka, R. ; Nagai, M. ; Okuyama, S. ; Kobayashi, T. ; Ito, N. ; Arita, K. ; Miyamoto, H.
Author_Institution :
ULSI Device Dev. Div., NEC Corp., Sagamihara, Japan
Abstract :
We have developed the two-step Cu electroplating (EP) technique using alkali-metal-free copper pyrophosphate bath for Cu seed enhancement EP step. Alkali-metal-free copper pyrophosphate bath realizes conformal thickening of thin Cu seed layer without dissolution of Cu seed layer due to high resistivity, high polarization, and low Cu dissolubility of the bath. The two-step technique brings excellent yield of the via-chain resistance in comparison with copper sulfate EP technique. Thus, two-step electroplating is a promising technique for future ULSI fabrication beyond the limitation of PVD seed technology.
Keywords :
ULSI; copper; electroplating; integrated circuit interconnections; integrated circuit metallisation; Cu; ULSI fabrication; alkali-metal-free copper pyrophosphate bath; conformal thickening; crystal orientation; damascene interconnect; electrical resistivity; seed enhancement step; two-step electroplating technique; via-chain resistance yield; Atherosclerosis; Copper; Etching; Filling; Indium tin oxide; Machinery; National electric code; Polarization; Product development; Ultra large scale integration;
Conference_Titel :
Interconnect Technology Conference, 2001. Proceedings of the IEEE 2001 International
Conference_Location :
Burlingame, CA, USA
Print_ISBN :
0-7803-6678-6
DOI :
10.1109/IITC.2001.930083
