Barrierless Cu–Ni–Nb thin films on silicon with high thermal stability and low electrical resistivity. Issue 24 (20th December 2013)

• Record Type: Journal Article
• Authors: Li, Xiao Na; Zhao, Li Rong; Li, Zhen; Liu, Li Jun; Bao, Cui Min; Chu, Jinn P.; Dong, Chuang
• Is Part Of: Journal of materials research. Volume 28:Issue 24(2013)
• Page Start: 3367
• Page End: 3373
• Publication Date: 2013-12-20
• Subjects: Cu, -- film, -- electrical properties; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1557/jmr.2013.355
• Languages: English
• ISSNs: 0884-2914

Abstract

Abstract: Abstract : In this paper, we demonstrate a thin film Cu–Ni–Nb alloy deposited directly on silicon, without a designated barrier, showing very high thermal stability at a temperature up to 700 °C for 1 h. Thin [Nb–Ni12 ]Cu x films were sputter deposited and annealed, and their material and electrical properties were studied. The results can be explained by the "cluster-plus-glue atom" model for stable solid solutions, where [Nb–Ni12 ] cuboctahedral clusters are embedded in a Cu matrix. In this model, the clusters are congruent with the Cu minimizing atomic interactions allowing a good stability. The properties of the films were found to be affected by the Ni/Nb ratios. Especially, the (Nb1.2/13.2 Ni12/13.2 )0.3 Cu99.7 film annealed at 500 °C for 1 h had the lowest electrical resistivity of about 2.7 μΩ cm. And even after 40 h annealing at 500 °C, it maintained a low resistivity of about 2.8 μΩ cm, demonstrating extremely high stabilities against silicide formation.