Hostname: page-component-76fb5796d-skm99 Total loading time: 0 Render date: 2024-04-25T12:50:04.670Z Has data issue: false hasContentIssue false
  • English
  • Français

Copper CMP with Composite Polymer Core - Silica Shell Abrasives: A Defectivity Study

Published online by Cambridge University Press:  01 February 2011

Silvia Armini ,
Caroline M. Whelan ,
Mansour Moinpour  and
Karen Maex
Silvia Armini
Affiliation:
armini@imec.be, IMEC/KULeuven, SPDT/ESAT, Kapeldreef 75, Leuven, 3001, Belgium
Caroline M. Whelan
Affiliation:
whelan@imec.be, IMEC, Leuven, 3001, Belgium
Mansour Moinpour
Affiliation:
mansour.moinpour@intel.com, INTEL, Santa Clara, CA, 95052, United States
Karen Maex
Affiliation:
maex@imec.be, KULeuven, Leuven, 3001, Belgium
Get access

Abstract

The results of copper Chemical Mechanical Planarization (CMP) experiments with a model slurry chemistry based on the combination of Glycine-water-Benzotriazole (Gly-H2O2-BTA), and different types of composite A (silane coupling agents between the polymer core and the silica shell) and B (electrostatic attraction between the polymer core and the silica shell) abrasives, are presented. While the presence of BTA allows a ten-fold reduction in the static etch rate from 95 nm/min. to 10 nm/min., combining oxidizer and complexing agent leads to removal rates higher than 400 nm/min. Different surface morphology and RMS roughness are observed after polishing with composite abrasives and different peroxide concentrations. Oxidizer concentrations as low as 0.1 vol.% lead to high non-uniformity and defectivity values. In particular, composite B performs better than pure colloidal/fumed silica during copper CMP using the IC-1000 pad, giving comparable Material Removal Rate (MRR), but a better surface finish due to the contribution of the elasticity of the polymer in gently transferring the applied load to the wafer surface. Cu CMP with pure polymer particles is a promising alternative to the hard inorganic material especially if combined with suitable surfactants that act from both particle stabilization and friction reduction / lubrication improvement perspectives.

The use of the medium/high-hardness pad IC-1000 is compared to the use of a soft Politex pad. In the former case, differences in terms of MRR, MRS roughness, and total defects are observed between the composite abrasives A and B; in the latter case, the behaviour of the two composites is similar. In the case of a soft pad in combination with composite abrasives, there is a remarkable improvement in the defectivity without any loss in MRR.

As revealed by SEM inspection of the composite particles collected in the slurry drain after CMP, for all the composites, the silica shell coverage is not disrupted by the shear forces and chemistry during the 1 min. polishing. Consequently, the stability and agglomeration properties of the particles in the complex Cu CMP chemistry can be helpful in explaining the experimental results in terms of MRR and surface finishing.

Keywords

CMPCudefects
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1079: Symposium N – Materials and Processes for Advanced Interconnects for Microelectronics , 2008 , 1079-N11-04
Copyright
Copyright © Materials Research Society 2008

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] Armini, S., Whelan, C. M., Maex, K., Hernandez, J. L., Moinpour, M., J. Electrochem. Soc., 154, 8, H667, (2007).Google Scholar
[2] Aksu, S., Doyle, F. M., J. Electrochem. Soc., 149, 6, G352, (2002).Google Scholar
[3] Deshpande, S., Kuiry, S. C., Klimov, M., Obeng, Y., Seal, S., J. Electrochem. Soc., 151, 11, G788, (2004).Google Scholar
[4] Hariharaputhiran, M., Zhang, J., Ramarajan, S., Keleher, J. J., Li, Y., Babu, S. V., J. Electrochem. Soc., 147, 10, 3820, (2000).Google Scholar
[5] Li, Z., Ina, K., Koshiyama, I., Philipossian, A., J. Electrochem. Soc., 152, 4, G299, (2005).Google Scholar
[6] Wrschka, P., Hernandez, J., Hsu, Y., Kuan, T. S., Oehrlein, G. S., Sun, H. J., Hansen, D. A., King, J., Fury, M. A., J. Electrochem. Soc., 146, 7, 2689, (1999)..Google Scholar
[7] Brown, N. J., Baker, P. C., Maney, R. T., Proceedings of SPIE, 306, 42, (1981).Google Scholar
[8] Zhang, F., Busnaina, A., Electrochem. Solid-State Lett., 1, 4, 184, (1998).Google Scholar
[9] Zhang, F., Busnaina, A., Ahmadi, G., J. Electrochem. Soc., 146, 7, 2665, (1999).Google Scholar
[10] Ahmadi, G., Xia, X., J. Electrochem. Soc., 148, 3, G99, (2001).Google Scholar
[11] Mazaheri, R., Ahmadi, G., J. Electrochem. Soc., 149, 7, G370 (2002).Google Scholar
[12] Mazaheri, R., Ahmadi, G., J. Electrochem. Soc., 150, 4, G233 (2003).Google Scholar
[13] Luo, J., Dornfeld, D. A., IEEE Transaction: Semiconductor Manufacturing, 16, 1, 45, (2003).Google Scholar
[14] Armini, S., Whelan, C. M., Smet, M., Eslava, S., Maex, K., Polymer Journal, 38, 8, 786, (2006).Google Scholar
[15] Armini, S., Eslava, S., Whelan, C. M., Terzieva, V., Maex, K., Proceedings of the American Chemical Society Colloid and Surface Science Symposium, June 12-15, 2005, Potsdam, New York, USA.Google Scholar
[16] Armini, S., Vakarelski, I. U., Whelan, C. M., Maex, K., Higashitani, K., Langmuir, 23, 4, 2007, (2007).Google Scholar
[17] Armini, S., Burtovyy, R., Luzinov, I., Whelan, C. M., Maex, K., Moinpour, M., Electrochemical and Solid-State Letters, 10, H74, (2007).Google Scholar
[18] Horcas, I., Fernandez, R., Gomez-Rodriguez, J. M., Colchero, J., Gomez-Herrero, J., Baro, A. M., Rev. Sci. Instrum., 78, 013705, (2007).Google Scholar
[19] Harihaputhiran, M., Ramarajan, S., Babu, S. V., MRS Symp. Proceedings Series, 566, 129, (1999).Google Scholar
[20] Steigerwald, J. M., Murarka, S. P., Gutmann, R. J., “Chemical Mechanical Planarization of Microelectronic Materials”, John Wiley and Sons Ed. New York, 1997.Google Scholar
[21] Schindler, P. W., Adv. Chem. Series, 67, 196, (1967).Google Scholar
[22] Kaanta, C. W., Bombardier, S. G., Cote, W. J., Hill, W. R., Kerszykowski, G., Landis, H. S., Poindexer, D. J., Pollard, C. W., Ross, G. H., Ryan, J. G., Wolff, S., Cronnin, J. E., in Proceedings of the 8th International VLSI Multilevel Interconnection Conference, VMIC, 1992, 226.Google Scholar
[23] Babu, S. V., Li, Y., Hariharaputhiran, M., Ramarajan, S., Zhang, J., Her, Y-S., Prendergast, J. E., in Proceedings of the 15th International VLSI Multilevel Interconnection Conference, VMIC, 1998, 443.Google Scholar
[24] Zeidler, D., Stavreva, Z., Plotner, M., Dresker, K., Microelectron. Eng., 33, 259, (1997).Google Scholar
[25] Notoya, T., Poling, G. W., Corrosion, 35, 193, (1979).Google Scholar
[26] Hariharaputhiran, M., Zhang, J., Ramarajan, S., Keleher, J. J., Li, Y., Babu, S. V., J. Electrochem. Soc., 147, 10, 3820, (2000).Google Scholar
[27] Armini, S., Whelan, C. M., Moinpour, M., Maex, K., Electrochem. Solid-State Lett., submitted.Google Scholar