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Contaminant Transport and Deposition Mechanisms

  • Alvin Lieberman

Abstract

Gases, vapors, and ions are more or less uniformly distributed in the air and diffuse rapidly throughout the cleanroom. The molecules of these materials have nearly the same dimensions and mass as the air molecules in the cleanroom and respond to changes in the environment essentially the same as the air molecules. Particles, however, have significant mass and inertia and do not necessarily move at the same rate or as soon as the air parcel in which the particles are located. Further, they may be retained on a surface or within a liquid for some time with small changes in their format. During this time, the particles may also react with the substrate material or collect other particles on their surface and grow to the point where they are released to the atmosphere or transported to other locations on or near that substrate. The particles can change significantly with time in both size and composition as a result of reactions to environmental conditions. An understanding of the mechanisms controlling particle deposition and transport is quite important in contamination control. By knowing more about how particles are transported to and deposited upon critical products, the procedures and the basis for designs used in contamination control systems are better understood in terms of how they minimize particle deposition and maximize particle removal after deposition. For these reasons, this chapter emphasizes particle transport and deposition mechanisms, with lesser emphasis on gas and vapor movement mechanisms. Concerning particle motion in liquids, the differences in fluid properties, such as viscosity and density, result in the liquids transferring much larger shear forces to the particles than can gas to affect particle motion. For this reason, liquidborne particle motion is discussed separately.

Keywords

Particle Motion Knudsen Number Particle Deposition Deposition Velocity Contaminant Transport 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Ananth, G. P., & Liu, B. Y. H., 1988. Particle Transport and Deposition in Computer Disk Drives. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 235–239, September 26, 1988, Los Angeles.Google Scholar
  2. Blitshteyn, M., 1986. The Use of Blow-off Guns in Semiconductor Manufacturing. Microcontamination 4(1):20–28.Google Scholar
  3. Brock, J. R., 1962. On the Theory of Thermal Forces Acting on Aerosol Particles. Journal of Colloid Science 17:768.CrossRefGoogle Scholar
  4. Cooper, D. W., 1986. Particle Contamination and Microelectronics Manufacturing: An Introduction. Aerosol Science and Technology 5( 12):287–299.Google Scholar
  5. Cooper, D. W., et al., 1988. Deposition of Submicron Aerosol Particles during Integrated Circuit Manufacturing: Theory. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 19–26, September 26, 1988, Los Angeles.Google Scholar
  6. Cooper, D. W., et al., 1989. Deposition of Submicron Aerosol Particles during Integrated Circuit Manufacturing: Experiments. Journal of Environmental Science 32(1):27–31.Google Scholar
  7. Donovan, R. P., et al., 1988. Experimental Study of Particle Deposition on Silicon Wafers under the Combined Effects of Electric Fields and Thermal Gradients. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 37–42, September 26, 1988, Los Angeles.Google Scholar
  8. Donovan, R. P., et al., 1990. Investigating Particle Deposition Mechanisms on Wafers Exposed to Aqueous Baths. Microcontamination 8(8):25–29.Google Scholar
  9. Fardi, B., & Liu, B. Y. H., 1990. Deposition of Particles on Spinning Computer Disks. Proceedings of the 36th Institute of Environmental Sciences Annual Technical Meeting, pp. 169–172, April 1990, New Orleans.Google Scholar
  10. Fissan, H. J., & Turner, J. R., 1988. Control of Particle Flux to Prevent Surface Contamination. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 33–36, September 26, 1988, Los Angeles.Google Scholar
  11. Frieben, W. R., 1989. The Effect of Cleanroom Design and Manufacturing Systems on the Microbiological Contamination of Aseptically Filled Products. Journal of Environmental Science 28(3):25–27.Google Scholar
  12. Fujii, S., et al., 1984. Studies on Design Theory of Laminar Flow Type Clean Room: Particle Deposition to the Surface. Proceedings of the 7th International Committee of Contamination Control Societies Conference, September 18–21. 1984. Paris.Google Scholar
  13. Fujii, S., et al., 1988. Measurements of Airflow Turbulence in a Clean Room and Particulate Behavior in the Boundary Layer on a Wafer. Proceedings of the 35th Institute of Environmental Sciences Annual Technical Meeting, King of Prussia, PA. May 3–5, 1988.Google Scholar
  14. Hablanian, M. H., 1989. If You Rough Slowly, Do You Get a Clean Vacuum Chamber? Research and Development 31(4):81–86.Google Scholar
  15. Inoue, M., et al., 1988. Aerosol Deposition on Wafer. Proceedings of 35th Institute of Environmental Sciences Annual Technical Meeting. King of Prussia, PA, May 3–5, 1988.Google Scholar
  16. Jennings, S. J., 1988. The Mean Free Path in Air. Journal of Aerosol Science 19(2):159–166.CrossRefGoogle Scholar
  17. Kaplan, C. R., & Gentry, J. W., 1988. Agglomeration of Chainlike Combustion Aerosols due to Brownian Motion. Aerosol Science and Technology 8(1): 11–28.CrossRefGoogle Scholar
  18. Liu, B. Y. H., & Ahn, K. H., 1987. Particle Deposition on Semiconductor Wafers. Aerosol Science and Technology 6(3):215–224.CrossRefGoogle Scholar
  19. Liu, B. Y. H., Pui, D. Y. H., & Lin, B. Y., 1986. Aerosol Charge Neutralization by a Radioactive Alpha Source. Particle Characterization 3(3): 111–116.CrossRefGoogle Scholar
  20. Ohmi, T., Inaba, H., & Takenami, T., 1989. Research on Adhesion of Particles to Charged Wafers Critical in Contamination Control. Microcontamination 7(10):29–42.Google Scholar
  21. Otani, Y., et al., 1989. Determination of Deposition Velocity onto a Wafer for Particles in the Size Range Between 0.03 and 0.8 μm. Journal of Aerosol Science 20(7):787–796.CrossRefGoogle Scholar
  22. Pui, D. Y. H., Ye, Y. & Liu, B. Y. H., 1988. Sampling Transport and Deposition of Particles in High Purity Gas Supply System. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 287–293. September 26, 1988, Los Angeles.Google Scholar
  23. Riley, D. J., & Carbonell, R. G., 1990. The Deposition of Liquid-Based Contaminants onto Silicon Surfaces. Proceedings of the 36th Institute of Environmental Sciences Annual Technical Meeting, pp. 224–228, April 1990, New Orleans.Google Scholar
  24. Ruuskanen, J., et al., 1990. Contamination in an Experimental Gallium Arsenide Etch System. American Industrial Hygiene Association Journal 51(1):8–13.CrossRefGoogle Scholar
  25. Sakata, S., et al., 1988. Aerosol Deposition on Wafer Surface. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 65–72, September 26, 1988, Los Angeles.Google Scholar
  26. Schwartz, A., & McDermott, W. T., 1988. Numerical Modelling of Submicron Particle Deposition in Pressurized Systems. Proceedings of the 9th International Committee of Contamination Control Societies Conference, pp. 78–85, September 26, 1988, Los Angeles.Google Scholar
  27. Stratmann, F., Peterson, T., & Fissan, H., 1988. Particle Deposition onto a Flat Surface from a Point Particle Source. Journal of Environmental Science 31(6):39–41.Google Scholar
  28. Wang, H. C, et al., 1989. Factors Affecting Particle Content in High-Pressure Cylinder Gases. Solid State Technology 32(5): 155–158.Google Scholar
  29. Welker, R. W., 1988. Equivalence between Surface Contamination Rates and Class 100 Conditions. Proceedings of the 35th Institute of Environmental Sciences Annual Technical Meeting, King of Prussia, PA, May 3–5, 1988.Google Scholar
  30. Wen, H. Y., & Kasper, G., 1989. On the Kinetics of Particle Reentrainment from Surfaces. Journal of Aerosol Science 20(4):483–498.CrossRefGoogle Scholar
  31. Whyte, W., 1986. Sterility Assurance and Models for Assessing Airborne Bacterial Contamination. Journal of Parenteral Science and Technology 40(5): 188–197.Google Scholar
  32. Yost, M., & Steinman, A., 1986. Electrostatic Attraction and Particle Control. Microcontamination 4(6): 18–27.Google Scholar

Copyright information

© Van Nostrand Reinhold 1992

Authors and Affiliations

  • Alvin Lieberman

There are no affiliations available

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