Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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Investigation of PEG(polyethyleneglycol) Removal Mechanism during UV/O2 Gas Phase Cleaning for Silicon Technology

UV/O2 가스상 세정을 이용한 실리콘 웨이퍼상의 PEG 반응기구의 관찰

  • 권성구 (군산대학교 신소재공학과) ;
  • 김도현 (한국과학기술원 생명화학공학과) ;
  • 김기동 (군산대학교 신소재공학과) ;
  • 이승헌 (군산대학교 신소재공학과)
  • Published : 2006.11.01
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Abstract

An experiment to find out the removal mechanism of PEG(polyethyleneglycol) by using UV-enhanced $O_2$ GPC (gas phase cleaning) at low substrate temperature below $200^{\circ}C$ was executed under various process conditions, such as substrate temperature, UV exposure, and $O_2$ gas. The possibility of using $UV/O_2$ GPC as a low-temperature in-situ cleaning tool for organic removal was confirmed by the removal of a PEG film with a thickness of about 200 nm within 150 sec at a substrate temperature of $200^{\circ}C$. Synergistic effects by combining photo-dissociation and photo oxidation can only remove the entire PEG film without residues within experimental splits. In $UV/O_2$ GPC with substrate temperatures higher than the glass transition temperature, the substantial increase in the PEG removal rate can be explained by surface-wave formation. The photo-dissociation of PEG film by UV exposure results in the formation of end aldehyde by dissociation of back-bone chain and direct decomposition of light molecules. The role of oxygen is forming peroxide radicals and/or terminating the dis-proportionation reaction by forming peroxide.

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References

  1. M. Hirose, S. Yokoyama, and Y. Yamakage, 'Characterization of photochemical processing', J. Vac. Sci. Technol. B, Vol. 3, No. 5, p. 1445, 1985
  2. M. C. Sun, D. H. Kim, and S. K. Kwon, 'Effect of $UV-O_2$, $NF_3/H_2$ surface preparation on the crystalline defects in silicon homoepitaxy (Part I. A study on photochemical surface preparation in series)', J. Crystal Growth, Vol 237/239, p. 1399, 2002 https://doi.org/10.1016/S0022-0248(01)02222-9
  3. K. Choi, S. Ghosh, J. Lim, and C. M. Lee, 'Removal efficiency of organic contaminants on Si wafer by dry cleaning using $UV/O_3$ and ECR plasma', Appl, Surf. Sci., Vol. 206, p. 355, 2003 https://doi.org/10.1016/S0169-4332(02)01215-1
  4. T. Takahagi, I. Nagai, A. Ishitani, H. Kuroda, and Y. Nagasawa, 'The formation of hydrogen passivated silicon single-crystal surfaces using ultraviolet cleaning and HF etching', J. Appl. Phys., Vol. 64, p. 3516, 1988 https://doi.org/10.1063/1.341489
  5. S. K. Kwon, K. N. Kim, C. W. Nam, and S. I. Woo, 'Effect of CO and $CO_2$ addition to the $CF_4/O_2$ gas system on the etching of a low-pressure chemical vapor deposition tungsten film', J. Vac. Sci. Technol. B, Vol. 13, No. 3, p. 914, 1995 https://doi.org/10.1116/1.588205
  6. S. K. Kwon, K. H. Kwon, B. W. Kim, J. M. Park, S. W. Yoo, K. S. Park, Y. K. Bae, and B. W. Kim, 'Characterization of via etching in $CHF_3/CF_4$ magnetically enhanced reactive ion etching using neural networks', ETRI J., Vol. 24, p. 211, 2002
  7. G. S. Oehrlein and Y. H. Lee, 'Reactive ion etching related Si surface residues and subsurface damage: Their relationship to fundamental etching mechanisms', J. Vac. Sci. Technol. A, Vol. 5, No.4, p. 1585, 1987
  8. P. K. Boyer, G. A. Roche, W. H. Ritchie, and G. J. Collins, 'Laser-induced chemical vapor deposition of $SiO_2$', Appl. Phys. Lett., Vol. 40, p. 716, 1982 https://doi.org/10.1063/1.93202
  9. T. Iwamoto and T. Ohmi, 'Ultra thin gate oxide reliability enhanced by carbon contamination free process', Appl. Surf. Sci., Vol. 117/118, p. 237, 1997
  10. H. W. Kim, Z. H. Zhou, and R. Reif, 'Room temperature wafer surface cleaning by in-situ ECR(electron cyclotron resonance) hydrogen plasma for silicon homoepitaxial growth', Thin Solid Film, Vol. 302, p. 169, 1997 https://doi.org/10.1016/S0040-6090(96)09548-X
  11. H. M. Buschbeck, A. Erhart, Y. Goeggel, C. Rosenblad, S. Wiltsche, J. Ramm, A. Dommann, and M. Kummer, 'Productionready dry cleaning and deposition for low-temperature Si and SiGe epitaxy', Appl. Surf. Sci., Vol. 224, p. 36, 2004 https://doi.org/10.1016/j.apsusc.2003.08.087
  12. S. K. Kwon, D. H. Kim, and J. T. Baek, 'Silicon epitaxial film growth on silicon substrate exposed to UV-excited $NF_3/H_2$ gas for native oxide removal', J. Crystal Growth, Vol. 198/199, p. 1039, 1999 https://doi.org/10.1016/S0022-0248(98)01077-X
  13. S. I. Raider, 'Carbon impurities at a $Si-SiO_2$ interface', Microelectronic engineering, Vol. 22, No. 1, p. 29, 1993 https://doi.org/10.1016/0167-9317(93)90124-N
  14. H. Gutleben, S. R. Lucas, C. C. Cheng, W. J. Choyke, and J. T. Yates, Jr., 'Thermal stability of the methyl group adsorbed on Si(100): $CH_3I$ surface chemistry', Surf. Sci. Lett., Vol. 257, No. 1-3, p. A566, 1991 https://doi.org/10.1016/0039-6028(91)90773-L
  15. M. L. Colaianni, P. J. Chen, H. Gutleben, and J. T. Yates, jr., 'Vibrational studies of $CH_3I$ on Si(100)-$(2{\times}1)$ : adsorption and decomposition of the methyl species', Chem. Phys. Lett., Vol. 191, No. 6, p. 561, 1992 https://doi.org/10.1016/0009-2614(92)85589-3
  16. R. C. Henderson, R. B. Marcus, and W. J. Polito, 'Carbide contamination of silicon surfaces', J. Appl. Phys., Vol. 42, No. 3, p. 1208, 1971
  17. K. Nakamura, S. Ichimura, A. Kurokawa, K. Koike, G. Inoue, and T. Fukuda, 'Ultrathin silicon oxide film on Si(100) fabricated by highly concentrated ozone at atmospheric pressure', J. Vac. Sci. Technol. A, Vol. 17, No. 4, p. 1275, 1999
  18. K. Asai, K. Komachi, K. Kamei, and H. Katahama, 'Hydrogen plasma irradiation and postannealing effects on crystalline quality at vicinal Si (100) surface', Applied Surf. Sci., Vol. 153, No. 2-3, p. 134, 2000
  19. C. G. Van de Walle, 'Energies of various configurations of hydrogen in silicon', Phys. Rev. B, Vol. 49, No. 7, p. 4579, 1994
  20. M. K. Weldon, V. E. Marsico, Y. J. Chabal, A. Agarwal, D. J. Eaglesham, J. Sapjeta, W. L. Brown, D. C. Jacobson, Y. Caudano, S. B. Christman, and E. E. Chaban, 'On the mechanism of the hydrogen-induced exfoliation of silicon', J. Vac. Sci. Technol. B, Vol. 15, No. 4, p. 1065, 1997 https://doi.org/10.1116/1.589416
  21. H. Bracht, N. A. Stolwijk, and H. Mehrer, 'Properties of intrinsic point defects in silicon determined by zinc diffusion experiments under nonequilibrium conditions', Phys. Rev. B, Vol. 52, No. 23, p. 16542, 1995
  22. H. Flicker, J. J. Loferski, and J. scoft-Monck, 'Radiation defect introduction rates in n- and p-type silicon in the vicinity of the radiation damage threshold', Phys. Rev., Vol. 128, No. 6, p. 2557, 1962 https://doi.org/10.1103/PhysRev.128.2557
  23. H. Okabe, 'Photochemistry of small molecules', John Wiley & Sons Inc., USA, 1978
  24. R. E. Emmert and R. L. Pigford, 'A study of gas absorption in falling liquid films', Chem. Eng. Prog., Vol. 50, p. 87, 1954