Radical-surface interactions plasma

Dimitrios Maroudas, Modeling of Radical-Surface Interactions in the Plasma-Enhanced Chemical Vapor Deposition of Silicon Thin Films Sanat Kumar, M. Antonio Floriano, and Athanassiors Z. Panagiotopoulos, Nanostructured Formation and Phase Separation in Surfactant Solutions Stanley I. Sandler, Amadeu K. Sum, and Shiang-Tai Lin, Some Chemical Engineering Applications of Quantum Chemical Calculations... 

Dimitries Maroudas, Modeling of Radical-Surface Interactions in the Plasma-Enhanced Chemical Vapor Deposition of Silicon Thin Films... 

Maroudas, D., Modeling of radical-surface interactions in the plasma-enhanced chemical vapor deposition of silicon thin films, in (A.K. Chakraborty, Ed.), Molecular Modeling and Theory in Chemical Engineering , vol. 28, p. 252. Academic Press, New York (2001). Maroudas, D. Multiscale modeling, Challenges for the chemical sciences in the 21st century Information and communications report , National Academies, Washington, DC. p. 133. 

Maroudas, D. Modeling of radical-surface interactions in the plasma-enhanced chemical vapor deposition of silicon thin films. In Molecular Modeling and Theory in Chemical Engineering Chakraborty, A.K., Ed. Academic Press New York, 2001 252-296. 

MODELING OF RADICAL-SURFACE INTERACTIONS IN THE PLASMA-ENHANCED CHEMICAL VAPOR DEPOSITION OF SILICON THIN FILMS... 

Ramalingam, S., Maroudas, D., and Aydil, E. S., Visualizing radical-surface interactions in plasma deposition processes Reactivity of SiHs radicals with Si surfaces. IEEE Trans. Plasma Sci. 27,104-105 (1999a). 

The main objective of this article is to summarize the work performed at the Max-Planck-Institute for Plasma Physics in Garching over the past few years relevant to plasma-surface interaction processes in the system hydrogen and carbon. This includes a short review of the properties of amorphous, hydrogenated carbon layers, further on abbreviated as a-C H, determination of reaction probabilities of reactive species such as atomic hydrogen and methyl radicals, and investigation of the simultaneous interaction of these species and low-energy ions with hydrocarbon surfaces. The reviewed ma-... 

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]. 

Assuming a dominant precursor for deposition simplifies tremendously the study of plasma-surface interactions. In spite of the oversimplification, it is worth examining the effects on the film structure and composition of growth simulations solely from a given chemically reactive radical. First, direct comparison with experimental data provides an assessment for the... 

The reaction mechanisms of plasma polymerization processes are not understood in detail. Poll et al [34] (figure C2.13.6) proposed a possible generic reaction sequence. Plasma-initiated polymerization can lead to the polymerization of a suitable monomer directly at the surface. The reaction is probably triggered by collisions of energetic ions or electrons, energetic photons or interactions of metastables or free radicals produced in the plasma with the surface. Activation processes in the plasma and the film fonnation at the surface may also result in the fonnation of non-reactive products. 

The plasma-wall interaction of the neutral particles is described by a so-called sticking model [136, 137]. In this model only the radicals react with the surface, while nonradical neutrals (H2, SiHa, and Si H2 +2) are reflected into the discharge. The surface reaction and sticking probability of each radical must be specified. The nature (material, roughness) and the temperature of the surface will influence the surface reaction probabilities. Perrin et al. [136] and Matsuda et al. [137] have shown that the surface reaction coefficient of SiH3 is temperature-independent at a value of = 0.26 0.05 at a growing a-Si H surface in a... 

A sticking model is used for the plasma-wall interaction [137]. In this model each neutral particle has a certain surface reaction coefficient, which specifies the probability that the neutral reacts at the surface when hitting it. In case of a surface reaction two events may occur. The first event is sticking, which in the case of a silicon-containing neutral leads to deposition. The second event is recombination, in which the radical recombines with a hydrogen atom at the wall and is reflected back into the discharge. 

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