Chemical vapor deposition, modeling

Armaou, A., and P.D. Christofides, Plasma Enhanced Chemical Vapor Deposition Modeling and Control, Chem. Eng. Sci., 54, 3305-3314 (1999). 

A. Em, V. Giovangigli, M. D. Smooke. Detailed modeling of three-dimensional chemical vapor deposition. J Cryst Growth 180 610, 1997. 

At the end of last century, a near frictionless carbon (NFC) coating was reported, which is practically hydrogen contained DLC film grown on steel and sapphire substrates using a plasma enhanced chemical vapor deposition (PECVD) system [50]. By using a ball on a disk tribo-meter, a super low friction coefficient of 0.001-0.003 between the films coated on both the ball and the disk was achieved [50]. A mechanistic model was proposed that carbon atoms on the surface are partially di-hydrogenated, resulting in the chemical inertness of the surface. Consequently, adhesive interaction becomes weak and super low friction is achieved [22],... 

Application of Supercomputers To Model Fluid Itansport and Chemical Kinetics in Chemical Vapor Deposition Reactors... 

Chemical vapor deposition (CVD) of carbon from propane is the main reaction in the fabrication of the C/C composites [1,2] and the C-SiC functionally graded material [3,4,5]. The carbon deposition rate from propane is high compared with those from other aliphatic hydrocarbons [4]. Propane is rapidly decomposed in the gas phase and various hydrocarbons are formed independently of the film growth in the CVD reactor. The propane concentration distribution is determined by the gas-phase kinetics. The gas-phase reaction model, in addition to the film growth reaction model, is required for the numerical simulation of the CVD reactor for designing and controlling purposes. Therefore, a compact gas-phase reaction model is preferred. The authors proposed the procedure to reduce an elementary reaction model consisting of hundreds of reactions to a compact model objectively [6]. In this study, the procedure is applied to propane pyrolysis for carbon CVD and a compact gas-phase reaction model is built by the proposed procedure and the kinetic parameters are determined from the experimental results. 

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... 

Cimdari TR, Sommerer SO (1997) Quantum modeling of the CVD of transition metal materials. Chemical Vapor Deposition 3(4), 183-192... 

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

For many applications, like chemical-vapor-deposition reactors, the semi-infinite outer flow is not an appropriate model. Reactors are often designed so that the incoming flow issues through a physical manifold that is parallel to the stagnation surface and separated by a fixed distance. Typically the manifolds (also called showerheads) are designed so that the axial velocity u is uniform, that is, independent of the radial position. Moreover, since the manifold is a solid material, the radial velocity at the manifold face is zero, due to the no-slip condition. One way to fabricate a showerhead manifold is to drill many small holes in a plate, thus causing a large pressure drop across the manifold relative to the pressure variations in the plenum upstream of the manifold and the reactor downstream of the manifold. A porous metal or ceramic plate would provide another way to fabricate the manifold. 

The details of the transitions and the vortex behavior depend on the actual channel dimensions and wall-temperature distributions. In general, however, for an application like a horizontal-channel chemical-vapor-deposition reactor, the system is designed to avoid these complex flows. Thus the ideal boundary-layer analysis discussed here is applicable. Nevertheless, one must exercise caution to be sure that the underlying assumptions of one s model are valid. 

The chemical vapor deposition (CVD) of CdTe thin films is used in the manufacture of highly efficient solar cells. To model this deposition process, a surface reaction mechanism is needed. 

In addition to the catalytic-ignition problem, this approach has been successfully implemented on opposed-flow strained-flame simulations with the inlet flow oscillating at high frequency [193]. It has also been used to model transient chemical-vapor deposition processes where the inlet flow is varies under a real-time control algorithm [324]. Although it is unlikely that a practical process-control system would be designed to induce extremely fast transients, it is important that the simulation remain stable to any potential controller command. 

There are numerous applications that depend on chemically reacting flow in a channel, many of which can be represented accurately using boundary-layer approximations. One important set of applications is chemical vapor deposition in a channel reactor (e.g., Figs. 1.5, 5.1, or 5.6), where both gas-phase and surface chemistry are usually important. Fuel cells often have channels that distribute the fuel and air to the electrochemically active surfaces (e.g., Fig. 1.6). While the flow rates and channel dimensions may be sufficiently small to justify plug-flow models, large systems may require boundary-layer models to represent spatial variations across the channel width. A great variety of catalyst systems use... 

W.G. Breiland, M.E. Coltrin, and P. Ho. Comparisons between a Gas-Phase Model of Silane Chemical Vapor Deposition and Laser-Diagnostic Measurements. J. Appl. Phys., 59 3267-3273,1986. 

M.E. Coltrin, RJ. Kee, and G. H. Evans. A Mathematical Model of the Fluid Mechanics and Gas-Phase Chemistry in a Rotating Disk Chemical Vapor Deposition Reactor. J. Electrochem. Soc., 136(3) 819-829,1989. 

M.E. Coltrin, RJ. Kee, G.H. Evans, E. Meeks, FM. Rupley, and J.F. Grcar. Spin A Fortran Program for Modeling One-Dimensional Rotating-Disk/Stagnation-Flow Chemical Vapor Deposition Reactors. Technical Report SAND91-8003, Sandia National Laboratories, 1991. 

C.R. Kleijn. Chemical Vapor Deposition Processes. In M. Meyyappan, editor, Computational Modeling in Semiconductor Processing, pages 97-216. Artech House, Boston, 1995. 

C.R. Kleijn. Computational Modeling of Transport Phenomena and Detailed Chemistry in Chemical Vapor Deposition—A Benchmark Solution. Thin Solid Films, 365 294-306,2000. 

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