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

fYear

2001

fDate

6-6 June 2001

Firstpage

277

Lastpage

279

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;

fLanguage

English

Publisher

ieee

Conference_Titel

Interconnect Technology Conference, 2001. Proceedings of the IEEE 2001 International

Conference_Location

Burlingame, CA, USA

Print_ISBN

0-7803-6678-6

Type

conf

DOI

10.1109/IITC.2001.930083

Filename

930083