Ion-surface interaction

Rabalais J W (ed) 1994 Low Energy Ion-Surface Interactions (Chichester Wiley)... 

A volume with contributions from several authors that treats ion-surface interactions at different energies. 

The plasma potential is the maximum value with which ions can be accelerated from the edge of the sheath towards the substrate, located at the grounded electrode. This may cause ion bombardment, which may induce ion-surface interactions such as enhancement of adatom diffusion, displacement of surface atoms, trapping or sticking of incident ions, sputtering, and implantation see Section 1.6.2.1. 

David B. Graves and Cameron F. Abrams, Molecular Dynamics Simulations if Ion-Surface Interactions with Applications to Plasma Processing Christian M. Lastoskie and Keith E. Gubbins, Characterization of Porous Materials Using Molecular Theory and Simulation... 

N. Herbots and co-workers, inj. W. Rabalais, ed., Low Energy Ion Surface Interaction, John Wiley Sons, Inc., New York, 1994. 

To overcome this problem, we have modified a commercial ion gun to generate a diffuse fast-atom beam [116, 117]. The ion beam neutralizer shown in Figure 7 consists of a multi-hole metal plate through which the primary ions pass. The ions are neutralized by the ion/surface interactions that occur as the beam passes through the metal aperatures and by charge-exchange reactions that occur within the gun assembly. A repeller grid is used to remove the residual ions from the neutralized beam. 

Let us consider two parallel plates immersed in an electrolyte solution. As is well-known the ions form a diffuse electric layer, bearing a charge opposite in sign to that of the surface, sandwiched between the two plates. Because of the strong interactions between the ions and water molecules, the ions are hydrated and the simplifying assumption is made that their configuration is the same everwhere in the system. Of course, if the ion-surface interactions favor adsorption of dehydrated counterions,... 

The polarization model is extended to account for the ion-ion and ion-surface interactions, not included in the mean field electrical potential. The role of the disorder on the dipole correlation length A, is modeled through an empirical relation, and it is shown that the polarization model reduces to the traditional Poisson Boltzmann formalism (modified to account for additional interactions) when X, becomes sufficiently small. 

The upper sign corresponds to a water-dielectric , and the lower one to a water-conductor type of interface. Equation (7) shows that a charge located next to a conductor will be attracted by its own image, and dielectrics in aqueous solutions will repel it. For a review of statistical-mechanical models of the double layer near a single interface we refer to [7], and here we would like only to illustrate how the image forces will alter the ion concentration and the electrostatic potential distribution next to a single wall. At a low electrolyte concentration the self-image forces will mostly dominate, and the ion-surface interaction will only be affected by the polarization due... 

Similar observations, regarding the adsorption sequences of cations and anions, have also been made for other oxides (a-Fe203, ZnO) and have led to a description of such oxide surfaces as structure promoting This representation constitutes an extension of the Gurney s interpretation of ion-ion interactions in solution to the ion-surface interactions. 

J.W. Rabalias, Low Energy Ion-Surface Interactions, John Wiley, Chichester (1994). 

Coronell, D.G., Hansen, D.E., Voter, A.F., Liu, C.-L., Liu, X.-Y. and Kress, J.D. (1998) Molecular Dynamics-based Ion-surface Interaction Modes for Ionized Physical Vapor Deposition Feature Scale Simulations. Appl. Phys. Lett., 73, 3860-3862. 

MOLECULAR DYNAMICS SIMULATIONS OF ION-SURFACE INTERACTIONS WITH APPLICATIONS TO PLASMA PROCESSING... 

The topic of this article is the use of molecular dynamics (MD) simulations of positive ion-surface interactions for insights into the chemical and physical processes that occur at surfaces immersed in glow discharge plasmas. To understand the signihcance of this topic, it is necessary to have some background in the technology and its major industrial application (Lieberman and Lichtenberg, 1994). The term plasma in this context refers... 

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