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.
Similar content being viewed by others
References
J. Warnock, J. Electrochem. Soc. 138, 2398-402, 1991.
S. Sundararajan, et al., J. Electrochem. Soc. 146, 761-66, 1999.
D. G. Thakurta, et al., Thin Solid Films 366, 181-90, 2000.
S. R. Runnels, J. Electrochem. Soc. 141, 1900-04, 1994.
D. Boning, et al., in “Chemical-Mechanical Polishing-Fundamentals and Challenges”, Proc. Mat. Res. Soc. 566, San Francisco, 197–209, 1999.
O. G. Chekina, et al., J. Electrochem. Soc. 145, 2100-06, 1998.
T.-K. Yu, et al., Proc. of the 1993 International Electron Devices Meeting, 35.4.1–4, 1994.
J. A. Greenwood and J. H. Tripp, J. Appl. Mech. 34, 153–59, 1967.
K. L. Johnson, Contact mechanics, Cambridge: Cambridge University Press, 1985.
I. S. Gradshtein and I. M. Ryzhik, Tables of Integrals, Series, and Products, New York and London: Academic Press, 1994.
J. M. Steigerwald, S. P. Murarka, and R. J. Gutmann, Chemical Mechanical Planarization of Microelectronic Materials, New York: John Wiley & Sons, Inc, 1997
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Vlassak, J.J. A Contact-Mechanics Based Model for Dishing and Erosion in Chemical-Mechanical Polishing. MRS Online Proceedings Library 671, 46 (2001). https://doi.org/10.1557/PROC-671-M4.6
Published:
DOI: https://doi.org/10.1557/PROC-671-M4.6