Hostname: page-component-7c8c6479df-5xszh Total loading time: 0 Render date: 2024-03-28T09:51:59.408Z Has data issue: false hasContentIssue false

Spectral Analysis of Frictional Forces in ILD CMP

Published online by Cambridge University Press:  01 February 2011

Ara Philipossian
Affiliation:
Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 USA
Daniel Rosales-Yeomans
Affiliation:
Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 USA
Leslie Charns
Affiliation:
Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721 USA
Chris Rogers
Affiliation:
Department of Mechanical Engineering, Tufts University, Medford, MA 02155 USA
Toshiroh Doy
Affiliation:
Department of Mechanical Engineering, Saitama University, Urawa, Saitama, 338-8570 JAPAN
Masaharu Kinoshita
Affiliation:
Rodel-Nitta Company, Tokyo, 104-0061 JAPAN
Get access

Abstract

Spectral analysis of real-time friction data obtained during ILD CMP is used to elucidate the tribology of the process in terms of stick-slip phenomena. Fourier transform analysis is employed to quantify the total amount of mechanical interaction in the pad-slurry-wafer interface as a function of various IC-1000 pad surface textures, PL-4217 fumed silica concentrations, relative pad-wafer velocities and applied wafer pressures. A new parameter termed the ‘Interfacial Interaction Index’ (γ) is defined and determined empirically by integrating the amplitude of the force spectra over a wide range of frequencies. Values of γ extracted from individual force spectra are in qualitative agreement with the tribological information obtained in previous studies using Stribeck curve analysis. This new method is remarkable since it has the potential to eliminate having to perform a multitude of experiments needed for constructing and interpreting Stribeck curves. For a given tribological mechanism, analysis of the spectra for various types of pad textures indicates significant differences between the K-Grooved pad and other types of pads. A qualitative model relating the observed spectra to pad storage modulus is presented as a potential explanation for the above observation.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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

1. Philipossian, A. and Olsen, S.. Proceedings of the CMP-MIC Conference, Marina Del Rey, CA (2003).Google Scholar
2. Philipossian, A. and Olsen, S.. Effect of slurry flow rate on pad life in ILD CMP. Submitted to the Journal of the Electrochemical Society, (2003).Google Scholar
3. Ludema, Kenneth C. Friction, Wear, Lubrication: A Textbook in Tribology. CRC Press, Inc., 1996.Google Scholar
4. Philipossian, A. and Mitchell, E.. Performing Mean Residence Time Analysis of CMP Processes. Micro, Vol. 20, No. 7 (2002).Google Scholar
5. Brigham, E. and Oren, H.. The Fast Fourier Transform and its applications. Prentice-Hall Inc., Inglewood Cliffs, New Jersey (1988).Google Scholar
6. Shi, F. and Zhao, B.. Modeling of chemical-mechanical polishing with soft pads. Applied Physics A, Vol. 67, p. 249252 (1998).Google Scholar