Performance of ultrathin alternative diffusion barrier metals for next - Generation BEOL technologies, and their effects on reliability

Author

Nogami, T. ; Chae, M. ; Penny, C. ; Shaw, T. ; Shobha, H. ; Li, Jie ; Cohen, Sholom ; Hu, C.-K. ; Zhang, Xiaobing ; He, Mengxun ; Tanwar, K. ; Patlolla, R. ; Chen, S.-T. ; Kelly, Jonathan ; Lin, Xingqin ; Straten, O. ; Simon, A. ; Motoyama, K. ; Bonilla,

Author_Institution

IBM in Albany Nano Sci. & Technol. Res. Center, IBM Corp., Albany, NY, USA

fYear

2014

fDate

20-23 May 2014

Firstpage

223

Lastpage

226

Abstract

In order to maximize Cu volume and reduce via resistance, barrier thickness reduction is a strong option. Alternative barriers for next-generation BEOL were evaluated in terms of barrier performance to O₂ and Cu diffusion, and effects on reliability. A clear correlation of O₂ barrier performance to electromigration was observed, suggesting that the key role of the barrier layer is to prevent oxidation of Cu or the Cu/barrier interface. Long-throw PVD-TaN showed superior O₂ barrier performance to alternative metals such as PEALD-TaN, thermal ALD-TaN, -TaN(Mn) and - MnN and MnSiO3 self-forming barrier.

Keywords

copper; diffusion barriers; electromigration; integrated circuit reliability; Cu; PEALD-TaN; barrier layer; barrier performance correlation; barrier thickness reduction; copper-barrier interface; electromigration; long-throw PVD-TaN; next generation BEOL technology; oxidation prevention; reliability effects; self-forming barrier; thermal ALD-TaN; ultrathin alternative diffusion barrier metal performance; Image color analysis; Ions; Manganese; Mobile communication; Oxidation; Reliability;

fLanguage

English

Publisher

ieee

Conference_Titel

Interconnect Technology Conference / Advanced Metallization Conference (IITC/AMC), 2014 IEEE International

Conference_Location

San Jose, CA

Print_ISBN

978-1-4799-5016-4

Type

conf

DOI

10.1109/IITC.2014.6831875

Filename

6831875