Skip to main content
Log in

Features of the Kinetics of Bulk and Heterogeneous Processes in CHF3 + Ar and C4F8 + Ar Plasma Mixtures

  • Published:
Russian Microelectronics Aims and scope Submit manuscript

Abstract

We carry out a comparative study of the kinetics of plasma-chemical processes and plasma composition in CHF3 + Ar and C4F8 + Ar mixtures under the conditions of a high-frequency (13.56 MHz) induction discharge. Using diagnostic methods and plasma modeling, the general features and differences of the plasma’s electrophysical parameters in the studied systems are established together with the key bulk processes that determine the stationary concentrations of neutral particles. Тhe CHF3 + Ar system in the range 0–75% Ar is shown to be characterized by lower values of the flux densities of the fluorine atoms and polymer of the forming radicals. Model analysis of the kinetics of the heterogeneous processes (etching, polymerization, degradation of the polymer film) confirmed the advantage of the C4F8 + Ar system of silicon etching anisotropy and etching selectivity compared to the SiO2/Si system.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1.
Fig. 2.
Fig. 3.

Similar content being viewed by others

REFERENCES

  1. Handbook of Plasma Processing Technology, Rossnagel, S.M., Cuomo, J.J., and Westwood, W.D., Eds., Park Ridge: Noyes, 1990.

    Google Scholar 

  2. Wolf, S. and Tauber, R.N., Silicon Processing for the VLSI Era, Vol. 1: Process Technology, New York: Lattice, 2000.

    Google Scholar 

  3. Roosmalen, A.J., Baggerman, J.A.G., and Brader, S.J.H., Dry Etching for VLSI, New York: Plenum, 1991.

    Book  Google Scholar 

  4. Lieberman, M.A. and Lichtenberg, A.J., Principles of Plasma Discharges and Materials Processing, New York: Wiley, 1994.

    Google Scholar 

  5. Standaert, T.E.F.M., Hedlund, C., Joseph, E.A., and Oehrlein, G.S., Role of fluorocarbon film formation in the etching of silicon, silicon dioxide, silicon nitride, and amorphous hydrogenated silicon carbide, J. Vac. Sci. Technol., A, 2004, vol. 22, pp. 53–60.

    Article  Google Scholar 

  6. Stoffels, W.W., Stoffels, E., and Tachibana, K., Polymerization of fluorocarbons in reactive ion etching plasmas, J. Vac. Sci. Technol., A, 1998, vol. 16, pp. 87–95.

    Article  Google Scholar 

  7. Ho, P., Johannes, J.E., and Buss, R.J., Modeling the plasma chemistry of C2F6 and CHF3 etching of silicon dioxide, with comparisons to etch rate and diagnostic data, J. Vac. Sci. Technol., A, 2001, vol. 19, pp. 2344–2367.

    Article  Google Scholar 

  8. Bose, D., Rao, M.V.V.S., Govindan, T.R., and Meyyappan, M., Uncertainty and sensitivity analysis of gas-phase chemistry in a CHF3 plasma, Plasma Sources Sci. Technol., 2003, vol. 12, pp. 225–234.

    Article  Google Scholar 

  9. Lim, N., Efremov, A., Yeom, G.Y., and Kwon, K.-H., On the etching characteristics and mechanisms of HfO2 thin films in CF4/O2/Ar and CHF3/O2/Ar plasma for nano-devices, J. Nanosci. Nanotechnol., 2014, vol. 14, pp. 9670–9679.

    Article  Google Scholar 

  10. Kokkoris, G., Goodyear, A., Cooke, M., and Gogolides, E., A global model for C4F8 plasmas coupling gas phase and wall surface reaction kinetics, J. Phys. D: Appl. Phys., 2008, vol. 41, p. 195211.

    Article  Google Scholar 

  11. Rauf, S. and Ventzek, P.L.G., Model for an inductively coupled Ar/C–C4F8 plasma discharge, J. Vac. Sci. Technol., A, 2002, vol. 20, pp. 14–23.

    Article  Google Scholar 

  12. Chun, I., Efremov, A., Yeom, G.Y., and Kwon, K.-H., A comparative study of CF4/O2/Ar and C4F8/O2/Ar plasmas for dry etching applications, Thin Solid Films, 2015, vol. 579, pp. 136–148.

    Article  Google Scholar 

  13. Yeom, G.Y. and Kushner, M.J., Si/SiO2 etch properties using CF4 and CHF3 in radio frequency cylindrical magnetron discharges, Appl. Phys. Lett., 1990, vol. 56, pp. 857–859.

    Article  Google Scholar 

  14. Lele, C., Liang, Z., Linda, X., Dongxia, L., Hui, C., and Tod, P., Role of CF2 in the etching of SiO2, Si3N4 and Si in fluorocarbon plasma, J. Semicond., 2009, vol. 30, p. 033005-1.

    Article  Google Scholar 

  15. Johnson, E.O. and Malter, L., A floating double probe method for measurements in gas discharges, Phys. Rev., 1950, vol. 80, pp. 58–70.

    Article  Google Scholar 

  16. Sugavara, M., Plasma Etching: Fundamentals and Applications, New York: Oxford Univ. Press, 1998.

    Google Scholar 

  17. Efremov, A., Min, N.K., Choi, B.G., Baek, K.H., and Kwon, K.-H., Model-based analysis of plasma parameters and active species kinetics in Cl2/X (X = Ar, He, N2) inductively coupled plasmas, J. Electrochem. Soc., 2008, vol. 155, pp. D777–D782.

    Article  Google Scholar 

  18. Kwon, K.-H., Efremov, A., Kim, M., Min, N.K., Jeong, J., and Kim, K., A model-based analysis of plasma parameters and composition in HBr/X (X = Ar, He, N2) inductively coupled plasmas, J. Electrochem. Soc., 2010, vol. 157, pp. H574–H579.

    Article  Google Scholar 

  19. Turban, G., Grolleau, B., Launay, P., and Briaud, P., A mass spectrometric diagnostic of C2F6 and CHF3 plasmas during etching of SiO2 and Si, Rev. Phys. Appl., 1985, vol. 20, pp. 609–620.

    Article  Google Scholar 

  20. Takahashi, K., Hori, M., and Goto, T., Characteristics of fluorocarbon radicals and CHF3 molecule in CHF3 electron cyclotron resonance downstream plasma, Jpn. J. Appl. Phys., 1994, vol. 33, pp. 4745–4758.

    Article  Google Scholar 

  21. Font, G.I., Morgan, W.L., and Mennenga, G., Cross-section set and chemistry model for the simulation of c‑C4F8 plasma discharges, J. Appl. Phys., 2002, vol. 91, pp. 3530–3538.

    Article  Google Scholar 

  22. Ho, P., Johannes, J.E., Buss, R.J., and Meeks, E., Chemical reaction mechanisms for modeling the fluorocarbon plasma etch of silicon oxide and related materials, Sandia Report, SAND2001-1292, 2001.

  23. Gray, D.C., Tepermeister, I., and Sawin, H.H., Phenomenological modeling of ion enhanced surface kinetics in fluorine-based plasma etching, J. Vac. Technol., B, 1993, vol. 11, pp. 1243–1257.

  24. Lee, C., Graves, D.B., and Lieberman, M.A., Role of etch products in polysilicon etching in a high-density chlorine discharge, Plasma Chem. Plasma Process., 1996, vol. 16, pp. 99–118.

    Article  Google Scholar 

  25. Matsui, M., Tatsumi, T., and Sekine, M., Relationship of etch reaction and reactive species flux in C4F8–Ar–O2 plasma for SiO2 selective etching over Si and Si3N4, J. Vac. Sci. Technol., A, 2001, vol. 19, pp. 2089–2096.

    Article  Google Scholar 

Download references

ACKNOWLEDGMENTS

The work was supported by the Russian Foundation for Basic Research, project no. 18-37-00064 mol_a.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to A. M. Efremov.

Additional information

Translated by G. Dedkov

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Murin, D.B., Efremov, A.M. & Kwon, KH. Features of the Kinetics of Bulk and Heterogeneous Processes in CHF3 + Ar and C4F8 + Ar Plasma Mixtures. Russ Microelectron 48, 99–106 (2019). https://doi.org/10.1134/S1063739719020070

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S1063739719020070

Navigation