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]Cux 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 (Nb1.2/13.2Ni12/13.2)0.3Cu99.7 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.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Change history
01 February 2014
An Erratum to this paper has been published: https://doi.org/10.1557/jmr.2013.391
References
C.S. Liu and L.J. Chen: Effects of substrate cleaning and film thickness on the epitaxial growth of ultrahigh vacuum deposited Cu thin films on (001)Si. J. Appl. Phys. 74, 5501 (1993).
J.P. Chu, C.H. Lin, and V.S. John: Cu films containing insoluble Ru and RuN on barrierless Si for excellent property improvements. Appl. Phys. Lett. 91, 132109 (2007).
J.P. Chu and C.H. Lin: Thermal stability of Cu(W) and Cu(Mo) films for advanced barrierless Cu metallization: Effects of annealing time. J. Electron. Mater. 35, 1933 (2006).
J.B. Zhou, T. Gustafsson, and E. Garfunkel: The structure and thermal behavior of Cu on ultrathin films of SiO2 on Si(111). Surf. Sci. 372, 21 (1997).
J.P. Chu, T.Y. Yu, C.H. Wu, C.H. Lin, S.F. Wang, and Q. Chen: Ultrathin diffusion barrier for copper metallization: A thermally stable amorphous rare-earth scandate. J. Electrochem. Soc. 157, H384 (2010).
S-Y. Changa, C-E. Li, S-C. Chiang, and Y-C. Huang: 4-nm thick multilayer structure of multi-component (AlCrRuTaTiZr)Nx as robust diffusion barrier for Cu interconnects. J. Alloys Compd. 515, 4 (2012).
Y. Wang, C. Hung, W. Lee, S. Chang, and Y. Wang: Under-layer behavior study of low resistance Ta/TaNx barrier film. Thin Solid Films 516, 5241 (2008).
D-C. Tsai, Y-L. Huang, S-R. Lin, d-R. Jung, S-Y. Chang, Z-C. Chang, M-J. Deng, and F-S. Shieu: Characteristics of a 10 nm-thick (TiVCr)N multi-component diffusion barrier layer with high diffusion resistance for Cu interconnects. Surf. Coat. Technol. 205, 5064 (2011).
A. Kohn, M. Eizenberg, and Y Shacham-Diamand: Evaluation of electroless deposited Co(W,P) thin films as diffusion barriers for copper metallization. Microelectron. Eng. 55, 297 (2001).
X.J. Wang, X.P. Dong, and C.H. Jiang: Thermal performance of sputtered Cu films containing insoluble Zr and Cr for advanced barrierless Cu metallization. Trans. Nonferrous Met. Soc. China 20, 217 (2010).
M.Y. Kwak, D.H. Shin, T.W. Kang, and K.N. Kim: Characteristics of TiN barrier layer against Cu diffusion. Thin Solid Films 339, 290 (1999).
C.H. Lin, J.P. Chu, T. Mahalingam, T.N. Lin, and S.F. Wang: Sputtered copper films with insoluble Mo for Cu metallization: A thermal annealing study. J. Electron. Mater. 32, 1235 (2003).
T. Mahalingam, C.H. Lin, L.T. Wang, and J.P. Chu: Preparation and characterization of sputtered Cu films containing insoluble Nb. Mater. Chem. Phys. 100, 490 (2006).
J. Zhang, Q. Wang, Y.M. Wang, C.Y. Li, L.S. Wen, and C. Dong: Revelation of solid solubility limit Fe/Ni = 1/12 in corrosion resistant Cu-Ni alloys and relevant cluster model. J. Mater. Res. 25, 328 (2010).
C. Dong, Q. Wang, J.B. Qiang, Y.M. Wang, N. Jiang, G. Han, Y.H. Li, J. Wu, and J.H. Xia: From clusters to phase diagrams: Composition rules of quasicrystals and bulk metallic glasses. J. Phys. D: Appl. Phys. 40, R273 (2007).
X.N. Li, L.J. Liu, X.Y. Zhang, J.P. Chu, Q. Wang, and C. Dong: Barrierless Cu-Ni-Mo interconnect films with high thermal stability against silicide formation. J. Electron. Mater. 41, 3447 (2012).
L.F. Nie, X.N. Li, J.P. Chu, Q. Wang, C.H. Lin, and C. Dong: High thermal stability and low electrical resistivity carbon-containing Cu film on barrierless Si. Appl. Phys. Lett. 96, 182105 (2010).
M.B. Tian and L.D. Liu: Science and Technology of Thin Film, 1st ed. (Machinery Industry Press, Beijing, 1991).
K. Barmak, A. Gungor, C. Cabral Jr., and J.M.E. Harper: Annealing behavior of Cu and dilute Cu-alloy films: Precipitation, grain growth, and resistivity. J. Appl. Phys. 94, 1605 (2003).
K. Barmak, C. Cabral Jr., J.M.E. Harper, and K.P. Rodbell: On the use of alloying elements for Cu interconnect applications. J. Vac. Sci. Technol., B. 24, 2485 (2006).
Y. Shacham-Diamand, A. Dedhia, D. Hoffstetter, and W.G. Oldham: Copper transport in thermal SiO2. J. Electrochem. Soc. 140, 2427 (1993).
Acknowledgment
This project was supported by the National Science Foundation of China (Grant Nos. 51271045 and 11174044).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Li, X.N., Zhao, L.R., Li, Z. et al. Barrierless Cu-Ni-Nb thin films on silicon with high thermal stability and low electrical resistivity. Journal of Materials Research 28, 3367–3373 (2013). https://doi.org/10.1557/jmr.2013.355
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1557/jmr.2013.355