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A plasma discharge due to a sustaining pulse of an alternating current plasma display panel was analyzed using a two-dimensional particle-in-cell code, and basic characteristics of the plasma discharge were calculated. The characteristics of the plasma discharge due to a sustaining pulse are as follows. (i) A large amount of space charge remained after drawing the discharge current. This excess space charge did not contribute to wall charge formation or ultraviolet radiation. (ii) The electron energy distribution function was evaluated and could be well fitted by the Druyvesteyn distribution in the high-energy region. The Druyvesteyn distribution was a consequence of the cross section for electron-Ne elastic scattering. (iii) The calculated ultraviolet radiation efficiency η of the plasma discharge due to a sustaining pulse was between 5.51% and 30.7%. Examination of the sensitivity of the efficiency to the electron temperature showed that reducing the electron temperature was a key to improving the efficiency. (iv) A detailed understanding of the conditions for a stable plasma discharge, memory margin, firing voltage, and electrode voltage of the sustaining pulse were obtained from the voltage transfer curve. The voltage transfer curve could be used to optimize the discharge cell design. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Discusses a study which used spherical and cylindrical many-particle models to stimulate radio frequency discharges. Computational formula for Poisson's equation; Theoretical models for radio frequency discharges; Difference between plasma potential and driven electrode potential.

Focuses on a general one-dimensional model to study the plasma-immersion ion implantation process in different coordinate systems. Analytic expressions for normal ion velocity distribution and other parameters; Effect of a charge-exchange collision on an ion; Equation concerning the average ion velocity at the target.

The steady-state behavior of the magnetized plasma-wall sheath has been studied through twodimensional particle simulations, which have shown that the sheath maintains itself in a strongly nonlinear, turbulent equilibrium, continuously driven by the edge Kelvin-Helmholtz instability. The sheath assumes a thickness of order l[sub x] ∼5ρ[sub i], and maintains large, long-lived vortices, with amplitudes δφ ∼ 2.5 T[sub i]/e, which drift parallel to the wall at half the ion thermal velocity. The sheath also maintains a large, spatially averaged potential drop from the wall to the plasma with Δφ≈ - 2T[sub i]/e, opposite in sign to that of the unmagnetized sheath. Accompanying the long-wavelength vortices are shorter-wavelength fluctuations, which induce an anomalous cross-field transport, scaling in accordance to Bohm diffusion when ω[sub pi] ≥ 2ω[sub ci]. At lower densities, ω[sub pi] < 2ω[sub ci], the diffusion coefficient has an additional factor, proportional to the density. These results permit the modeling of the cross-field sheath by a simple effective boundary condition. [ABSTRACT FROM AUTHOR]

The time-dependent behavior of a transversely magnetized, two-dimensional plasma-wall sheath has been studied through particle simulations, with the aim of modeling plasma behavior in the vicinity of the limiters and walls of magnetized plasma devices. The model assumes a magnetic field perfectly parallel to the confining surfaces. The simulations have shown that the cross-field sheath between a wall and a plasma is a self-sustaining turbulent boundary layer, with strong potential fluctuations and anomalous particle transport. The driving mechanism for this turbulence is the Kelvin-Helmholtz instability, which arises from the sheared particle drifts created near the wall. In this paper, the transient behavior leading to the turbulent steady state is presented, and the processes of linear growth, vortex saturation, and vortex coalescence are examined. An analytic model for the boundary Kelvin-Helmholtz instability is derived and shown to correctly predict the growth rates of the long-wavelength modes. In a companion paper, the steady-state structure and behavior of the cross-field sheath will be discussed in detail. [ABSTRACT FROM AUTHOR]