Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-22T03:20:41.959Z Has data issue: false hasContentIssue false

A Contact-Mechanics Based Model for Dishing and Erosion in Chemical-Mechanical Polishing

Published online by Cambridge University Press:  18 March 2011

Joost J. Vlassak*
Affiliation:
Division of Engineering and Applied Sciences, Harvard University 311 Pierce Hall, 29 Oxford Street, Cambridge MA 02138
Get access

Abstract

We present a new model for dishing and erosion during chemical-mechanical planarization. According to this model, dishing and erosion is controlled by the local pressure distribution between features on the wafer and the polishing pad. The model uses a contact mechanics analysis based on the work by Greenwood to evaluate the pressure distribution taking into account the compliance of the pad as well as its roughness. Using the model, the effects of pattern density, line width, applied down-force, selectivity, pad properties, etc. on both dishing and erosion can be readily evaluated. The model may be applied to CMP used for oxide planarization, metal damascene or shallow trench isolation.

The model is implemented as an algorithm that quickly calculates the evolution of the profile of a set of features on the wafer during the polishing process. With proper calibration of the process parameters, it can be used as a tool in optimizing the CMP process and implementing CMP design rules.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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 Warnock, J., J. Electrochem. Soc. 138, 2398–402, 1991.Google Scholar
2 Sundararajan, S., et al., J. Electrochem. Soc. 146, 761–66, 1999.10.1149/1.1391678Google Scholar
3 Thakurta, D. G., et al., Thin Solid Films 366, 181–90, 2000.Google Scholar
4 Runnels, S. R., J. Electrochem. Soc. 141, 1900–04, 1994.10.1149/1.2055024Google Scholar
5 Boning, D., et al., in “Chemical-Mechanical Polishing-Fundamentals and Challenges”, Proc. Mat. Res. Soc. 566, San Francisco, 197209, 1999.Google Scholar
6 Chekina, O. G., et al., J. Electrochem. Soc. 145, 2100–06, 1998.10.1149/1.1838603Google Scholar
7 Yu, T.-K., et al., Proc. of the 1993 International Electron Devices Meeting, 35.4.1–4, 1994.Google Scholar
8 Greenwood, J. A. and Tripp, J. H., J. Appl. Mech. 34, 153–59, 1967.10.1115/1.3607616Google Scholar
9 Johnson, K. L., Contact mechanics, Cambridge: Cambridge University Press, 1985.Google Scholar
10 Gradshtein, I. S. and Ryzhik, I. M., Tables of Integrals, Series, and Products, New York and London: Academic Press, 1994.Google Scholar
11 Steigerwald, J. M., Murarka, S. P., and Gutmann, R. J., Chemical Mechanical Planarization of Microelectronic Materials, New York: John Wiley & Sons, Inc, 1997 Google Scholar