JSTS:Journal of Semiconductor Technology and Science

The Institute of Electronics and Information Engineers (대한전자공학회)
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Use of In-Situ Optical Emission Spectroscopy for Leak Fault Detection and Classification in Plasma Etching

  • Received : 2012.09.12
  • Accepted : 2013.03.05
  • Published : 2013.08.31
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Abstract

In-situ optical emission spectroscopy (OES) is employed for leak detection in plasma etching system. A misprocessing is reported for significantly reduced silicon etch rate with chlorine gas, and OES is used as a supplementary sensor to analyze the gas phase species that reside in the process chamber. Potential cause of misprocessing reaches to chamber O-ring wear out, MFC leaks, and/or leak at gas delivery line, and experiments are performed to funnel down the potential of the cause. While monitoring the plasma chemistry of the process chamber using OES, the emission trace for nitrogen species is observed at the chlorine gas supply. No trace of nitrogen species is found in other than chlorine gas supply, and we found that the amount of chlorine gas is slightly fluctuating. We successfully found the root cause of the reported misprocessing which may jeopardize the quality of thin film processing. Based on a quantitative analysis of the amount of nitrogen observed in the chamber, we conclude that the source of the leak is the fitting of the chlorine mass flow controller with the amount of around 2-5 sccm.

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References

  1. C. Lee and M. A. Lieberman, "Global Model of Ar, $O_{2}$, $Cl_{2}$, and $Ar/O_{2}$ High-density Plasma Discharge," JVST A: Vacuum, Surfaces, and Films, Vol. 13, No. 2, pp. 368-380, 1995. https://doi.org/10.1116/1.579366
  2. M. Weling, C. T. Gabriel, W. Jain, and D. Pramanik, "Method for Leak Detection in Etching Chamber," US patent 5,222,957, Jun. 1996.
  3. Y. Li, J.D. Wang, Z.H. Huang, H.Q. Xu, and X.-T. Zhou, "Monitoring Leaking Gases by OP-FTRI Remote Sensing," J. Environ. Sci. Health A, Vol. 37, No. 8, pp. 1453-1462, 2002. https://doi.org/10.1081/ESE-120013269
  4. H. Tanaka, "Plasma leak monitoring method, plasma processing apparatus and plasma Processing Method, US patent 7,217,942 B2, May 2007.
  5. B. Kim, M. Kwon, D. Kim. S. W. Baik, G. S. May, J. Jung, and B. Woo, "In-Situ Leak Detection of Plasma Processing Chamber Using Neural Network and Optical Emission Spectroscopy," Materials and Manufacturing Processes, Vol. 26 pp. 218-222, 2011. https://doi.org/10.1080/10426914.2010.492054
  6. B. S. Kim, S. H. Chun, S.-S. Han, G. S. May, and S. J. Hong, "Wavelength Selection for the Analysis of the Plasma Etch Process Using Optical Emission Spectroscopy," In Proc. 18th Korean Semiconductor Conference, Jeju Island, Korea, TP1-25, 2011.
  7. S. J. Hong and G. S. May, "Neural-Network-Based Sensor Fusion of Optical Emission and Mass Spectroscopy Data for Real-Time Fault Detection in Reactive Ion Etching," IEEE Trans. Ind. Electron., Vol. 52, No. 4, pp. 1063-1072, 2005. https://doi.org/10.1109/TIE.2005.851663
  8. J. H. Ahn, J. M. Gu, S. Y. Lee, K. Lee, G. S. May, and S. J. Hong, "Real-time Arc Detection and the Analysis of Exited Particles During Plasma Etching Using Optical Emission Spectroscopy (OES) and Plasma Eyes Chromatic System (PECS), AEC/APC Symposium, Austin, TX, 2010.
  9. S. J. Hong and G. S. May, "Neural Network-Based Real-Time Malfunction Diagnosis of Reactive Ion Etching using In-Situ Metrology Data," IEEE Trans. Semi. Manufac., Vol. 17, No. 3, pp. 408-421, 2004. https://doi.org/10.1109/TSM.2004.831952