DOI QR코드

DOI QR Code

CFD-based Fire Accident Impact Analysis in Clean Room for semiconductor PR Process

반도체 PR 공정의 클린룸내 CFD 기반 화재 사고 영향 분석

  • Received : 2021.08.13
  • Accepted : 2021.12.10
  • Published : 2021.12.31

Abstract

The PR (Photo Resist) process in the semiconductor process is a process that uses a mixture of flammable substances. Due to the process equipment is installed in a clean room and when flammable substances leak, there is a high risk of suffocation, fire, and explosion. It is necessary to analyze the impact of accidents that may occur during operation and to evaluate whether the safety of workers can be guaranteed. In this study, the value of radiant heat and temperature change at the monitor point set up virtual inside the clean room was confirmed through CFD simulation of 10 leak and fire scenarios using the FLACS CFD - Fire Module. A fire that occurs inside a clean room transfers high radiant heat to the inter-story structure, but its scope is quite limited, and it is unlikely that it will collapse in a single fire accident. There was no scenario in which two stairs leading to the exit were exposed to high radiant heat at the same time due to a fire accident, therefore workers were able to escape in case of a fire. In addition, it was confirmed that the level of radiant heat and temperature rise rapidly decreased as they moved downstairs. According to the API 520 standard, workers exposed to 6.31 kW/m2 of radiant heat that workers can withstand for 30 seconds were confirmed that it was possible to sufficiently escape from the inside.

반도체 공정 중 PR (Photo Resist) 공정은 여러 인화성 물질을 혼합하여 사용하는 공정으로, 공정 장비가 Clean Room 내 설치되어 인화성 물질이 누출되는 경우 질식, 화재, 폭발 사고로 이어질 위험성이 크므로, 물질 누출시 발생할 수 있는 사고에 대한 영향을 분석하고, 작업자들의 안전을 보장할 수 있는지 평가하는 것이 필요하다. 본 연구는 FLACS CFD - Fire Module을 이용하여 10개의 누출, 화재 시나리오에 대한 CFD Simulation을 통해 Clean Room 내부 가상으로 설정한 Monitor Point에서의 복사열 및 온도 변화 값을 확인하였다. Clean Room 내부에서 발생한 화재는 층간 구조물에 높은 복사열을 전달하지만, 그 범위가 상당히 제한적이며, 단일 화재 사고로 인해 붕괴될 가능성이 희박하다. 화재 사고로 인해 탈출구로 이어지는 2 곳의 계단이 동시에 높은 복사열에 노출되는 시나리오는 없어, 화재 발생시 작업자가 탈출 가능하였다. 또한 복사열 및 온도 상승의 수준은 아래층으로 이동하면서 급격하게 낮아지는 것을 확인하였으며, API 520의 기준에 따라 작업자가 30초 동안 버틸 수 있는 복사열인 6.31 kW/m2에 노출된 작업자도 화재가 발생한 Clean Room 내부에서 충분히 탈출할 수 있음을 확인하였다.

Keywords

References

  1. Woodburn, P. J. and Britter, R. E., "CFD Simulation of a Tunnel Fire-Part I", Fire Safety Journal, 26(1), 35-62, (1996) https://doi.org/10.1016/0379-7112(96)00018-5
  2. Woodburn, P. J. and Britter, R. E., "CFD Simulation of a Tunnel Fire-Part II", Fire Safety Journal, 26(1), 63-90, (1996) https://doi.org/10.1016/0379-7112(96)00019-7
  3. Roh, J. S., Ryou, H. S., Park, W. H. and Jang, Y. J., "CFD Simulation and Assessment of Life Safety in a Subway Train Fire", Tunnelling and Underground Space Technology, 24(4), 447-453, (2009) https://doi.org/10.1016/j.tust.2008.12.003
  4. Jang, C. B. and Choi, S., "Simulation and Damage Analysis of an Accidental Jet Fire in a High-Pressure Compressed Pump Shelter", Safety and Health at Work, 8(1), 42-48, (2017) https://doi.org/10.1016/j.shaw.2016.06.005
  5. Yang, R., Khan, F., Yang, M., Kong, D. and Xu, C., "A Numerical Fire Simulation Approach for Effectiveness Analysis of Fire Safety Measures in Floating Liquefied Natural Gas Facilities", Ocean Engineering, 157, 219-233, (2018) https://doi.org/10.1016/j.oceaneng.2018.03.052
  6. Wang, J., Yu, X. and Zong, R., "A Dynamic Approach for Evaluating the Consequences of Toxic Gas Dispersion in the Chemical Plants Using CFD and Evacuation Modelling", Journal of Loss Prevention in the Process Industries, 65, 104156, (2020) https://doi.org/10.1016/j.jlp.2020.104156
  7. D'Silva, S., Mulders, T., Stock, H. and Erdmann, A., "Modeling the Impact of Shrinkage Effects on Photoresist Development", JM3, 20(1), 014602, (2021)
  8. Gexcon AS, "FLACS-CFD v21.1 User's Manual", 59-60, (2021)
  9. IOGP, "Risk Assessment Data Directory-Process Release Frequencies", IOGP Report 434-01, (2010)
  10. American Petroleum Institute, "API Standard 521 Pressure-relieving and Depressuring Systems", Sixth Edition, (2014)