Hostname: page-component-8448b6f56d-xtgtn Total loading time: 0 Render date: 2024-04-24T03:19:27.805Z Has data issue: false hasContentIssue false

Measuring substrate-independent modulus of dielectric films by instrumented indentation

Published online by Cambridge University Press:  31 January 2011

Jennifer Hay*
Affiliation:
Agilent Technologies, Oak Ridge, Tennessee 37830
*
a) Address all correspondence to this author. e-mail: jenny.hay@agilent.com
Get access

Abstract

Substrate influence is a common problem when using instrumented indentation (also known as nanoindentation) to evaluate the mechanical properties of thin films. In this work, finite element analysis was used to develop an ad hoc model that predicts the substrate influence when testing thin dielectric films on silicon. The model was evaluated experimentally using three sets of films that were nominally the same except for thickness. Using the model significantly reduced the measurement error for the thinnest films (<250 nm) by accurately accounting for the influence of the substrate. The model also significantly reduced the measurement uncertainty, because properties were evaluated using larger indents that would normally be unduly affected by the substrate. The process for developing this model may be useful in developing other ad hoc models for analyzing film-substrate systems.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Oliver, W.C. and Pharr, G.M.: An improved technique for determining hardness and elastic modulus using load and displacement sensing experiments. J. Mater. Res. 7, 1564 (1992).Google Scholar
2.Doerner, M.F. and Nix, W.D.: A method for interpreting the data from depth-sensing indentation instruments. J. Mater. Res. 1, 601 (1986).CrossRefGoogle Scholar
3.King, R.B.: Elastic analysis of some punch problems for a layered medium. Int. J. Solids Struct. 23, 1657 (1987).CrossRefGoogle Scholar
4.Gao, H., Chiu, C-H., and Lee, J.: Elastic contact versus indentation modeling of multi-layered materials. Int. J. Solids Struct. 29, 2471 (1992).Google Scholar
5.Menčík, J., Munz, D., Quandt, E., Weppelmann, E.R., and Swain, M.V.: Determination of elastic modulus of thin layers using nanoindentation. J. Mater. Res. 12, 2475 (1997).CrossRefGoogle Scholar
6.Song, H.: Selected mechanical problems in load and depth sensing indentation testing. Ph.D. Thesis, Rice University, Houston, TX, 1999.Google Scholar
7.Rar, A., Song, H., and Pharr, G.M.: Assessment of new relation for the elastic compliance of a film-substrate system, in Thin Films: Stresses and Mechanical Properties IX, edited by Ozkan, C. S., Freund, L.B., Cammarata, R.C., and Gao, H. (Mater. Res. Soc. Symp. Proc. 695, Warrendale, PA, 2002), L10.10, pp. 431438.Google Scholar
8.Xu, H. and Pharr, G.M.: An improved relation for the effective elastic compliance of a film/substrate system during indentation by a flat cylindrical punch. Scr. Mater. 55(4), 315 (2006).Google Scholar
9.Bec, S., Tonck, A., Georges, J.M., Georges, E., and Loubet, J.L.: Improvements in the indentation method with a surface force apparatus. Philos. Mag. A 74, 1061 (1996).CrossRefGoogle Scholar
10.Roche, S., Bec, S., and Loubet, J.L.: Analysis of the elastic modulus of a thin polymer film, in Mechanical Properties Derived from Nanostructuring Materials, edited by Bahr, D.F., Kung, H., Moody, N.R., and Wahl, K.J. (Mater. Res. Soc. Symp. Proc. 778, Warrendale, PA, 2003), U4.8, pp. 117122.Google Scholar
11.Hay, J.C., Bolshakov, A., and Pharr, G.M.: A critical examination of the fundamental relations in the analysis of nanoindention data. J. Mater. Res. 14, 2296 (1999).CrossRefGoogle Scholar