Dynamical [ital N]-body simulations of Coulomb scattering in plasma sheaths

Journal Article · Tue Dec 15 00:00:00 EST 1992 · Physical Review A. General Physics; (United States)

DOI:https://doi.org/10.1103/PhysRevA.46.7815· OSTI ID:6933032

Farouki, R T; Hamaguchi, S; Surendra, M; Dalvie, M ^[1]

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1. IBM Thomas J. Watson Research Center, P.O. Box 218, Yorktown Heights, New York 10598 (United States)

[ital N]-body simulations are used to assess the importance of discrete ion-ion Coulomb interactions in an electron-free plasma sheath, where ordinary Debye screening is ineffective. The angular dispersion [theta][sub rms] of the ion flux incident on the cathode is found to have a power-law dependence on a parameter [Omega] measuring the graininess'' of the sheath electric field, and an explanation for the observed exponent in this relation is postulated in terms of diffusion theory. In the [ital Coulomb] [ital logarithm], a lower cutoff [ital b][sub min] equal to a fraction of the mean ion-ion distance at the plasma-sheath boundary is determined, while the upper cutoff [ital b][sub max] appears to be no more than about ten times the sheath thickness [ital d]; no sustained logarithmic growth of [theta][sub rms][sup 2] with the lateral extent [ital a] over which Coulomb interactions are taken into account was observed. For sheath parameters representative of the low-pressure weakly ionized discharges used in very-large-scale-integration manufacturing processes, the dispersion due to Coulomb scattering in the sheath is typically [theta][sub rms][approx lt]0.1[degree].

• OSTI ID: 6933032
• Journal Information: Physical Review A. General Physics; (United States), Vol. 46:12; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
PLASMA SHEATH
ION-ION COLLISIONS
COULOMB SCATTERING
ELECTRIC DISCHARGES
MANY-BODY PROBLEM
SIMULATION
BASIC INTERACTIONS
COLLISIONS
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
INTERACTIONS
ION COLLISIONS
SCATTERING
700380* - Elementary & Classical Processes in Plasmas- (1992-)