Citation

Noda S, Hirai R, Komiyama H, Shimogaki Y. Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 2004; 43(9 A): 6001-6007.

Copyright

(Copyright © 2004)

DOI

10.1143/JJAP.43.6001

PMID

unavailable

Abstract

Aiming to realize a conductive passivation layer for copper interconnection, the solid-gas reactions of cobalt films with silane and with disilane to form cobalt suicides are experimentally investigated. X-ray photoelectron spectroscopy revealed that cobalt suicides layers of up to 6 nm thickness can be selectively formed in the reaction at 473-673 K within 5 min without detectable silicon deposition on silicon dioxide, a common inter-metal dielectric layer. Rapid thermal oxidation experiments revealed that the silicided cobalt layers had better anti-oxidation performance than untreated cobalt layers, and the effect of silicidation was to suppress copper out-diffusion through the cobalt layers. Because cobalt-based alloys can be selectively electroless-plated on copper, selective silicidation of cobalt layers will be easily incorporated into device processing.

Language: en

Keywords

Diffusion; Copper; Passivation; Cobalt silicide; Cobalt suicide; X ray photoelectron spectroscopy; Cobalt; Metallizing; Antioxidants; Conductive passivation layer; Copper metallization; Disilane; Selective silicidation; Silane; Silanes