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Effects of Elevated Temperature Annealing on the Structure and Hardness of Copper/niobium Nanolayered Films

Published online by Cambridge University Press:  01 August 2005

A. Misra*
Affiliation:
Materials Science and Technology Division, MS G755, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
R.G. Hoagland
Affiliation:
Materials Science and Technology Division, MS G755, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

We investigated the effects of elevated temperature vacuum annealing on the morphological stability and hardness of self-supported, textured, polycrystalline Cu–Nb nanolayered films with individual layer thickness varying from 15 to 75 nm. Films with layer thickness greater than approximately 35 nm are found to resist layer pinch-off and spheroidization even after long annealing times at 700 °C, while films with layer thickness ∼15 nm exhibit layer pinch-off and evolve into an equiaxed grain microstructure. Nanoindentation measurements indicate almost no change in hardness after annealing for films that retain the layered morphology, in spite of the increase of in-plane grain dimensions. Significant decreases in hardness are noted for films that develop a coarsened equiaxed grain microstructure after annealing. The mechanism that leads to the development of a thermally stable nanolayered structure is analyzed. Also, the relative effects of in-plane grain size and layer thickness on the multilayer hardness are discussed.

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Articles
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1Clemens, B.M., Kung, H. and Barnett, S.A.: Structure and strength of multilayers. MRS Bull. 24(2), 20 (1999).CrossRefGoogle Scholar
2Misra, A. and Kung, H.: Deformation behavior of nanostructured metallic multilayers. Adv. Eng. Mater. 3(4), 217 (2001).3.0.CO;2-5>CrossRefGoogle Scholar
3Phillips, M.A., Clemens, B.M. and Nix, W.D.: Microstructure and nanoindentation hardness of Al/Al3Sc multilayers. Acta Mater. 51, 3171 (2003).CrossRefGoogle Scholar
4Barnett, S.A., Madan, A., Kim, I. and Martin, K.: Stability of nanometer-thick layers in hard coatings. MRS Bull. 28(3), 169 (2003).CrossRefGoogle Scholar
5Kung, H., Jervis, T.R., Hirvonen, J.P., Mitchell, T.E. and Nastasi, M.: High-temperature structural stability of MoSi2-based nanolayer composites. J. Vac. Sci. Technol., B 13, 1126 (1995).CrossRefGoogle Scholar
6Lee, H.J., Kwon, K.W., Ryu, C. and Sinclair, R.: Thermal stability of a Cu/Ta multilayer: An intriguing interfacial reaction. Acta Mater. 47, 3965 (1999).Google Scholar
7Hong, S.I., Hill, M.A., Sakai, Y., Wood, J.T. and Embury, J.D.: On the stability of cold drawn, 2-phase wires. Acta Metall. Mater. 43, 3313 (1995).Google Scholar
8Kampe, J.C. Malzhan, Courtney, T.H. and Leng, Y.: Shape instabilities of plate-like structures. Acta Metall. 37, 1735 (1989).CrossRefGoogle Scholar
9Sharma, G., Ramanujan, R.V. and Tiwari, G.P.: Instability mechanisms in lamellar microstructures. Acta Mater. 48, 875 (2000).CrossRefGoogle Scholar
10Knoedler, H.L., Lucas, G.E. and Levi, C.G.: Morphological stability of copper-silver multilayer thin films at elevated temperatures. Metall. Mater. Trans. A. 34A, 1043 (2003).CrossRefGoogle Scholar
11Josell, D., Coriell, S.R. and McFadden, G.B.: Evaluating the zero creep conditions for thin film and multilayer thin film specimens. Acta Metall. Mater. 43, 1987 (1995).Google Scholar
12Josell, D. and Spaepen, F.: Surfaces, interfaces, and changing shapes in multilayered films. MRS Bull. 24(2), 39 (1999).CrossRefGoogle Scholar
13Josell, D., Carter, W.C. and Bonevich, J.E.: Stability of multilayer structures: Capillary effects. Nanostruct. Mater. 12, 387 (1999).CrossRefGoogle Scholar
14Lewis, A.C., Josell, D. and Weihs, T.P.: Stability in thin film multilayers and microlaminates: The role of free energy, structure, and orientation at interfaces and grain boundaries. Scripta Mater. 48, 1079 (2003).CrossRefGoogle Scholar
15Troche, P., Hoffmann, J., Heinemann, K., Hartung, F., Schmitz, G., Freyhardt, H.C., Rudolph, D., Thieme, J. and Guttmann, P.: Thermally driven shape instabilities of Nb/Cu multilayer structures: Instability of Nb/Cu multilayers. Thin Solid Films 353, 33 (1999).Google Scholar
16Zhai, Q., Kong, D., Morrone, A., and Ebrahimi, F.: Characterization of high strength Cu/Ag multilayered composites, in Electrochemical Synthesis and Modification of Materials, edited by And, P.C.ricacos, Corcoran, S.G., Delplancke, J-L., Moffat, T.P., and Searson, P.C. (Mater. Res. Soc. Symp. Proc. 451, Pittsburgh, PA, 1997) pp. 489494.Google Scholar
17Bobeth, M., Hecker, M., Pompe, W., Schneider, C.M., Thomas, J., Ullrich, A. and Wetzig, K.: Thermal stability of nanoscale Co/Cu multilayers, Z. Metallkde. 92, 810 (2001).Google Scholar
18Misra, A., Hoagland, R.G. and Kung, H.: Thermal stability of self-supported nanolayered Cu/Nb films. Philos. Mag. 84, 1021 (2004).Google Scholar
19Anderson, P.M., Bingert, J.F., Misra, A. and Hirth, J.P.: Rolling textures in nanoscale Cu/Nb multilayers. Acta Mater. 51, 6059 (2003).CrossRefGoogle Scholar
20Thornton, J.A.: High rate thick film growth. Ann. Rev. Mater. Sci. 7, 239 (1977).Google Scholar
21Sridhar, N., Rickman, J.M. and Srolovitz, D.J.: Multilayer film stability. J. Appl. Phys. 82,4852 (1997).CrossRefGoogle Scholar
22Gong, H.R. and Liu, B.X.: Unusual alloying behavior at the equilibrium immiscible Cu-Nb interfaces. J. Appl. Phys. 96, 3020 (2004).CrossRefGoogle Scholar
23Raabe, D. and Ge, J.: Experimental study on the thermal stability of Cr filaments in a Cu–Cr–Ag in situ composites. Scripta Mater. 51, 915 (2004).CrossRefGoogle Scholar
24Shewmon, P.: Diffusion in Solids, 2nd ed. (TMS, Warrendale, PA, 1989).Google Scholar
25Porter, D.A. and Easterling, K.E.: Phase Transformations in Metals and Alloys, 2nd ed. (Chapman & Hall, London, U.K., 1992).CrossRefGoogle Scholar
26Brown, A.M. and Ashby, M.F.: Acta Metall., 28, 1085 (1980).Google Scholar
27Vanleuken, H., Lodder, A. and Degroot, R.A.: Ab initio electronic structure calculations on the Nb/Cu multilayer system. J. Phys.: Condens. Matter 3, 7651 (1991).Google Scholar
28Venkatraman, R. and Bravman, J.C.: Separation of film thickness and grain boundary strengthening effects in Al thin films on Si. J. Mater. Res. 7, 2040 (1992).CrossRefGoogle Scholar
29Thompson, C.V.: The yield stress of polycrystalline thin films. J. Mater. Res. 8,237 (1993).CrossRefGoogle Scholar
30Hoagland, R.G., Kurtz, R.J. and Henager, C.H.: Slip resistance of interfaces and the strength of metallic multilayer composites. Scripta Mater. 50, 775 (2004).CrossRefGoogle Scholar
31Hansen, N. and Ralph, B.: The strain and grain size dependence of the flow stress of copper. Acta Metall. 30, 411 (1982).CrossRefGoogle Scholar
32Adams, M.A., Roberts, A.C. and Smallman, R.E.: Yield and fracture in polycrystalline niobium. Acta Metall. 8, 328 (1960).CrossRefGoogle Scholar