Pore-sealing by etch-byproduct followed by ALD-Ta adhesion layer for Cu/porous low-k interconnects

Author

Furuya, Akira ; Soda, Eiichi ; Yoneda, Katsurni ; Yoshie, Tom ; Okamura, Hiroshi ; Shimada, Masanobu ; Ohtsuka, Nobuyulu ; Ogawa, Shinichi

Author_Institution

Dept. of Res., Semicond. Leading Edge Technol., Inc., Ibaraki, Japan

fYear

2004

Firstpage

39

Lastpage

41

Abstract

Increase of process steps by pore-sealing and low via yield by low adhesion between Cu and barrier metal are cost issues when atomic layer deposited (ALD) barrier metal process is integrated into Cu/porous low-k interconnects. In order to solve these issues, etch-byproduct in-situ deposited on the sidewall and ALD-Ta is proposed. The etch-byproduct successfully prevented Ta penetration into the porous low-k film without increase process steps. ALD-Ta film of 0.8 nm, deposited by exposures of pentakisdimethylaminotantalium (PDMAT) and He/H₂ plasma to the substrate in turn, demonstrated strong adhesion layer as same as the conventional PVD barrier. Via yield of single-damascene Cu/porous low-k interconnects with the etch-byproduct was improved by substituting ALD-Ta for ALD-TaN.

Keywords

atomic layer deposition; copper; etching; integrated circuit interconnections; organic compounds; tantalum; 0.8 nm; ALD barrier metal process; ALD-Ta adhesion layer; ALD-Ta film; ALD-TaN; Cu; PVD barrier; Ta; atomic layer deposited; etch-byproduct in-situ deposition; low via yield; pentakisdimethylaminotantalium; pore sealing; porous low-k film; porous low-k interconnects; single-damascene Cu interconnects; Adhesives; Atomic layer deposition; Costs; Dielectric materials; Dielectric substrates; Etching; Optical films; Plasma applications; Plasma measurements; Silicon carbide;

fLanguage

English

Publisher

ieee

Conference_Titel

Interconnect Technology Conference, 2004. Proceedings of the IEEE 2004 International

Print_ISBN

0-7803-8308-7

Type

conf

DOI

10.1109/IITC.2004.1345677

Filename

1345677