Plasma-surface interactions profile

Absorption spectroscopy and laser induced fluorescence (LIF), give access to the concentration of molecules, atoms, and ions in the ground state. LIF is enable to achieve highly spatial and time resolved analyses. This technique is thus particularly suitable to investigate composition changes in the plasma, and obtain spatial or time concentration profiles. Published results in fluorine plasmas using absorption [25-27] and LIF [28-32] mainly concern temperature measurements [25] or the quantification of CFV radicals [26-31] in fluorocarbon-based plasmas and SOx in SF6—02 discharges [32], Recently LIF has been used to measure plasma-surface interaction products [33]. 

Glow discharges or plasmas have been used extensively to promote chemical reactions for thin-film etching and deposition in a variety of technologically important areas. The reactive chemical atmosphere and complex discharge-surface interactions in these systems permit the attainment of unique etch profiles and film properties. 

Application of a quantity of solution, in this case protein solution, to a column filled with appropriate substrate, leads to an exchange between the solute and the surface, and movement with the solvent front such that the emerging solute profile contains complete information concerning the kinetics of adsorption/desorption. Apart from the interaction of solute with surface, concurrent three-dimensional diffusion often occurs, and perhaps occlusion, if the substrate is porous. Nevertheless, the option of deducing interfacial kinetics from the elution profile in a flowing system has a certain elegance and relevance to the performance of blood plasma proteins in vivo. 

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