David B. Mitzi
Journal of Materials Chemistry
Various mathematical solutions to the convective-diffusion equation for noninteracting Brownian particles were carried out to predict deposition of submicrometer particles onto a flat surface in viscous, three-dimensional (axisymmetric) stagnation-point flow at clean-room velocities (∼ 100 cm/s). The particle deposition aspects modeled included electrostatics, inasmuch as both diffusion and electrostatics are the dominant mechanisms expected. The results were obtained in terms of dimensionless groups for deposition, convective-diffusion, and electrostatic attraction. It was found that the deposition velocity can be well approximated by a simple combination of the convective-diffusion velocity and the eletro-static velocity. These results are translated into practical terms, examples are given, and the predictions are compared with predictions made by other methods. A disk 20 cm in diameter charged to 2000-V potential is shown to attract a particle 0.1 μm in diameter so as to produce an electrostatic deposition velocity 180 times larger than the diffusion deposition velocity, giving it a deposition velocity nearly equal to that of a particle 10 μm in diameter settling under gravity. © 1989 Elsevier Science Publishing Co., Inc.
David B. Mitzi
Journal of Materials Chemistry
J.K. Gimzewski, T.A. Jung, et al.
Surface Science
Andreas C. Cangellaris, Karen M. Coperich, et al.
EMC 2001
T.N. Morgan
Semiconductor Science and Technology