Accession Number : ADA310369

Title :   Direct Simulation Monte Carlo Study of H/H2 and H/H2/CO Mixtures for Diamond Chemical Vapor Deposition,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC CENTER FOR REACTIVE FLOW AND DYNAMICAL SYSTE MS

Personal Author(s) : Sinkovits, Robert S. ; DeVore, C. R.

PDF Url : ADA310369

Report Date : 13 JUN 1996

Pagination or Media Count : 57

Abstract : One dimensional direct simulation Monte Carlo calculations have been carried out on H/H2 and H/H2/CO mixtures under operating conditions typical of diffusion-dominated diamond chemical vapor deposition processes. Mechanisms have been included in the model for the adsorption and recombination of hydrogen atoms on the diamond surface and the dissociation of molecular hydrogen at the interior of the reactor. Hydrogen atom fluxes and recombinative and conductive heat fluxes to the diamond surface are calculated as a function of pressure, gas composition, hydrogen dissociation and surface reaction probabilities, reactor temperature, and distance between the activating source and substrate. The numerical calculations are shown to be in excellent agreement with analytical results in the limiting regimes of free-streaming particles at low pressures and continuum hydrodynamics at high pressures.

Descriptors :   *SIMULATION, *DIAMONDS, *CHEMICAL VAPOR DEPOSITION, *MONTE CARLO METHOD, *HYDROGEN, *CARBON MONOXIDE, SOURCES, ACTIVATION, COMPUTATIONS, MOLECULES, ADSORPTION, PROBABILITY, NUMERICAL ANALYSIS, LOW PRESSURE, HIGH PRESSURE, SUBSTRATES, ATOMS, SURFACE REACTIONS, DIFFUSION, RECOMBINATION REACTIONS, HEAT FLUX, DISSOCIATION, CONDUCTION(HEAT TRANSFER), HYDRODYNAMICS, MOLECULAR PROPERTIES.

Subject Categories : Physical Chemistry
      Inorganic Chemistry
      Coatings, Colorants and Finishes
      Statistics and Probability
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE