| In the present work, low pressure radio-frequency (RF) plasma glow discharge, typical of those generated in the plasma processing industry, is numerically modeled via two well-established continuum models. The local field approximation model equations are solved in both a parallel-plate and a cylindrical reactor using a finite difference scheme. The effects of reactor pressure and applied RF voltage on the plasma parameters are examined. In the local energy approximation model, a high-order finite volume method is employed in a one-dimensional geometry. Here, temporal discretization is performed via backward difference schemes of first and second orders. Utilizing the deferred correction technique, high-order Lagrange polynomials are used to calculate the convection and diffusion fluxes at the cell faces, as well as the gradient fields at the cell centers. To evaluate the accuracy and performance of the method, comparisons with respect to CPU time, accuracy level and order are carried out among various methods and resolutions. Depending on the spatial scheme method, spatial error convergence exhibits up to fourth-order global trend with increasing the number of control volumes.;After the spatial distribution of the time-averaged, quasi-steady-state plasma variables are achieved from the local field approximation model, (sub-)micron-sized dust particles injected into the plasma are tracked in a Lagrangian framework. In doing so, the transient equations for particles motion and charge, together with the various forces acting on each particle, are considered. In the case of a single particle in a parallel-plate reactor, the abilities of two of the well-known ion drag expressions in modeling the particle dynamics are examined. Also, transient characteristic of charging process of smaller particles with respect to their motion time scale is elaborated. Further, in the presence of a temperature gradient in the plasma chamber, the qualitative effect of the thermophoretic force on the particle motion is discussed. In a cylindrical plasma chamber, equilibrium configurations of a few interacting dust particles are modeled. Direct comparison of the results with experiment demonstrates excellent qualitative agreement. Based on the ion focus phenomenon, a physical model is formulated and proven successful in simulating the vertically aligned structures. |
