Electron and Chemical Kinetics in the Low-Pressure RF Discharge Etching of Silicon in SF6

IEEE Transactions on Plasma Science

Volumn 14, Issue 2, 1986, Pages 145-155

  Kline, L E ^a  

^a WESTINGHOUSE ELECTRIC COMPANY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CHEMICAL REACTIONS - REACTION KINETICS; ELECTRIC FIELDS; MATHEMATICAL STATISTICS - MONTE CARLO METHODS; PLASMAS; SEMICONDUCTING SILICON - ETCHING;

BOLTZMANN EQUATION; SULFUR HEXAFLUORIDE;

ELECTRIC DISCHARGES;

EID: 0022704633     PISSN: 00933813     EISSN: 19399375     Source Type: Journal    
DOI: 10.1109/TPS.1986.4316517     Document Type: Article

References (44)

1. H. F. Winters, J. W. Coburn, and E. Kay, “Plasma etching—A ‘pseudo-black-box’ approach,” J. Appl. Phys., vol. 48, pp. 4973–4983, 1977. M. J. Kushner, “A kinetic study of the plasma-etching process. 1. A model for the etching of Si and SiO 2 in C n F m /O 2 and C n F m /H 2 plasmas,” J. Appl. Phys., vol. 53, pp. 2923–2938, 1982. H. F. Winters, J. W. Coburn, and T. J. Chuang, “Surface processes in plasma-assisted etching environments,” J. Vac. Sci. Technol. B, vol. 1, pp. 469–480, 1983.
2. C. A. Zarowin, “A theory of plasma-assisted chemical vapor transport processes,” J. Appl. Phys., vol. 57, pp. 929–942, 1985.
3. C. A. Zarowin, “Relation between the RF discharge parameters and plasma etch rates, selectivity, and anisotropy,” J. Vac. Sci. Technol. A, vol. 2, pp. 1537–1549, 1984.
4. M. J. Kushner, H. M. Anderson, and P. J. Hargis, “Simulation of spatially dependent excitation rates and power deposition in RF discharges for plasma etching,” in Proc. Mat. Res. Soc., 1985.
5. D. Edelson and D. Flamm, “Computer simulation of a CF 4 etching plasma,” J. Appl. Phys., vol. 56, pp. 1522–1531, 1984.
6. K. E. Greenberg and J. T. Verdeyen, “Kinetic processes of NF 2 etchant gas discharges,” J. Appl. Phys., vol. 57, pp. 1596–1601, 1985.
7. K. Tachibana, M. Nishida, H. Harima, and Y. Urano, “Diagnostics and modeling of a methane plasma used in the chemical vapor deposition of amorphous carbon films,” J. Phys. D., vol. 17, pp. 1727-1742, 1984.
8. K. Tachibana, T. Okuyama, H. Harima, and Y. Urano, “Diagnostics and modeling of plasmas used for the CVD of a - C : H a - Si : H and a - Si x - C 1 - x : H films,” presented at the Intl. Symp. of Plasma Chem., Eindhoven, Netherlands, July 1985.
9. M. J. Kushner, “Monte-Carlo simulation of electron properties in RF parallel plate capacitively coupled discharges,” J. Appl. Phys., vol. 54, pp. 4958–4965, 1983.
10. A. Garscadden, G. L. Duke, and W. F. Bailey, “Electron kinetics of silane discharges,” Appl. Phys. Lett., vol. 43, pp. 1012–1014, 1983.
11. K. M. Eisele, “SF 6, a preferable etchant of plasma etching silicon,” J. Electrochem. Soc., vol. 128, pp. 123–126, 1981.
12. L. E. Kline, “Computer simulation of SF 6 etching of silicon,” Bull. Amer. Phys. Soc., vol. 29, p. 151, 1984.
13. L. E. Kline, D. K. Davies, C. L. Chen, and P. J. Chantry, “Dielectric properties for SF 6 and SF 6 mixtures predicted from basic data,” J. Appl. Phys., vol. 50, pp. 6789–6798, 1979.
14. T. Yoshizawa, Y. Sakai, H. Tagashira, and S. Sakamoto, “Boltzmann equation analysis of the electron swarm development in SF 6,” J. Phys. D., vol. 12, pp. 1839–1852, 1979.
15. E. Marode and J. P. Boeuf, “A Monte Carlo analysis of an electron swarm in a non-uniform field,” J. Phys. D., vol. 15, pp. 2169–2187, 1984.
16. T. Nimura and M. Hayashi, “Importance of attachment cross-sections of F - formation for the effective ionization coefficients in SF 6,” J. Phys. D., vol. 17, pp. 2215–2223, 1984.
17. M. Yousfi, P. Segur, and T. Vassiliadis, “Solution of the Boltzmann equation with ionization and attachment: Application to SF 6,” J. Phys. D., vol. 18, pp. 359–375, 1985.
18. C. M. Horwitz, “RF Sputtering-voltage division between two electrodes,” J. Vac. Sci. Technol. A, vol. 1, pp. 60–68, 1983.
19. R. A. Gottscho and M. L. Mandich, “Time resolved optical diagnostics of radio frequency plasmas,” J. Vac. Sci. Technol. A, vol. 3, pp. 617–624, 1985.
20. S. D. Rockwood, “Elastic and inelastic cross sections of electron-Hg scattering from transport data,” Phys. Rev. A, vol. 8, pp. 2348–2358, 1973.
21. W. B. Lacina, “Theoretical modeling of molecular and electron kinetic processes,” Final Rep., Office of Naval Res., Contract N00014-78-C-0499, Jan. 1979.
22. L. E. Kline and J. G. Siambis, “Computer simulation of electron avalanches and streamers,” Phys. Rev., vol. A5, pp. 794–799, 1972.
23. T. Stanski and B. Adamczyk, “Measurements of dissociative ionization cross sections of SF 6 by using double collector cycloidal mass spectrometer,” lnt. J. Mass Spectrom. and Ion Phys., vol. 46, pp. 31–34, 1983. P. A. Schulz, A. S. Sudbo, E. R. Crane, Y. R. Shen, and Y. T. Lee, “Multiphoton dissociation of SF 6 by a molecular beam method,” J. Chem. Phys., vol. 72, p. 4985, 1980. S. Trajmar and A. Chutjian, “Electron impact excitation of SF 6,” J. Phys. B., vol. 10, pp. 2943–2949, 1977.
24. K. Rohr, “Vibrational Excitation of SF 6 by low-energy electron impact,” J. Phys. B., vol. 10, pp. 1175–1179, 1977.
25. L. S. Frost and A. V. Phelps, “Rotational excitation and momentum transfer cross sections for electrons in H 2 and N 2 from transport coefficients,” Phys. Rev., vol. 127, pp. 1621–1633, 1962.
26. R. d’Agostino and D. Flamm, “Plasma etching of Si and SIO 2 in SF 6 - O 2 mixtures,” J. Appl. Phys., vol. 52, pp. 162–167, 1981. R. d’Agostino, V. Colaprico, and F. Cramarossa, “The use of ‘actinometer’ gases in optical diagnostics of plasma etching mixtures: SF 6 - O 2,” Plasma Chem. and Plasma Proc., vol. 1, pp. 365–375, 1981.
27. J. J. Wagner and W. W. Brandt, “D.C. plasma etching of silicon by sulfur hexafluoride, mass spectrometric study of the discharge products,” Plasma Chem. and Plasma Proc., vol. 1, pp. 201–215, 1981.
28. G. Turban, J. Pasquereau, M. Rapeaux, Y. Catherine, and B. Groileau, “Decomposition and recombination of CF 4 in plasma etching,” in Electrochemical Society Extended Abstracts 81–2. Pennington, NJ: Electrochem. Soc., 1981, pp. 636–638.
29. C. C. Tang and D. W. Hess, “Tungsten etching in CF 4 and SF 6 discharges,” J. Electrochem. Soc., vol. 131, pp. 115–120, 1984.
30. C. W. Gear, Numerical Initial Value Problems in Ordinary Differential Equations. Englewood Cliffs, NJ: Prentice-Hall, 1971.
31. P. J. Chantry, private communication, 1985.
32. E. W. McDaniel, Collision Phenomena in Ionized Gases. New York: Wiley, 1964, ch. 10.
33. P. J. Chantry, A. V. Phelps, and G. J. Schulz, “Theory of electron collision experiments at intermediate and high gas densities,” Phys. Rev., vol. 152, pp. 81–98, 1966.
34. H. W. Ellis, E. W. McDaniel, D. L. Albritton, L. A. Viehland, S. L. Lin, and E. A. Mason, “Transport properties of gaseous ions over a wide range, Part II,” Atomic Data and Nuclear Data Tables, vol. 22, pp. 179–217, 1978.
35. K. P. Brand and H. Jungblut, “The interaction potentials of SF 6 ions in SF 6 parent gas determined from mobility data,” J. Chem. Phys., vol. 78, pp. 1999–2007, 1983.
36. J. B. Thompson, “Negative ions in the positive column of the oxygen discharge,” Proc. Phys. Soc., vol. 73, pp. 818–821, 1959. G. L. Rogoff, “Ambipolar diffusion coefficients for discharges in attaching gases,” J. Phys. D., vol. 18, pp. 1533–1545, 1985.
37. B. H. Mahan, “Recombination of gaseous ions,” in Advances in Chemical Physics, I. Prigogine and S. A. Rice, Eds. New York: Wiley, 1973.
38. J. N. Bardsley, A. Herzenberg, and F. Mandl, in Atomic Collision Processes, M. R. C. McDowell, ed. Amsterdam: North Holland, 1964.
39. D. Hansen, H. Jungblut, and W. F. Schmidt, “Electron detachment from negative ions in sulphur hexafluoride,” J. Phys. D., vol. 16, pp. 1623–1643, 1983.
40. A. Picard, G. Turban, and B. Grolleau, “Positive and negative ions in SF 6 plasma,” in Proc. 7th Intl. Symp. Plasma Chem. (Eindhoven, The Netherlands), 1985, pp. 570–575.
41. V. M. Donnelly, D. L. Flamm, W. C. Dautremont-Smith, and D. J. Werder, “Anisotropic etching of Si0 2 in low frequency CF 4 /O 2 and NF 3 /Ar plasmas,” J. Appl. Phys., vol. 55, pp. 242–252, 1984.
42. H. G. Lergon, M. Venugopalan, and K. G. Mueller, “Mass spectrometer-wall probe diagnostics of Ar discharges containing SF 6 and/or 0 2 : Reactive ions in etching plasmas,” Plasma Chem. Plasma Proc., vol. 4, pp. 107–118, 1984.
43. L. E. Kline and W. D. Partlow, “Experiments and modeling of methane-silane plasmas,” in Proc. 1985 IEEE Intl. Conf. Plasma Sci., 1985, p. 15.
44. A. Gupta and H. D. Toong, “Microprocessors—The first twelve years,” Proc. IEEE, vol. 71, pp. 1236–1256, 1983.