The gas jet deposition is now one of the effective methods of a film coating .In this work the numerical Monte Carlo simulation of the C2F4 (as precursor) supersonic flow interacting with the substrate was performed for previous experiments with teflon-like film deposition.The simulation provides the determination of all macroscopic parameters of the flow.Besides, it is possible to obtain the translational and internal energy distribution for molecules colliding with a surface. All specific conditions of deposition are determined by the following parameters: source stagnation pressure and temperature, geometry and size of the nozzle, location and orientation of a substrate, Knudsen number of the flow over a substrate, temperature of a substrate.
Authors have studied the series of new gas dynamic schemes for vacuum deposition (cases 1-3).
1. By interaction of two identical opposite supersonic gas mixture jets (97.5 % of H2 and 2.5 % of C2F4) in the subsonic region of the jet interaction the temperature of heavy component can be elevated few times higher than the initial stagnation temperature of mixtures. The relative concentration of C2F4 in this region exceeds this value in the stagnation chambers a few times. After that gas endures the fan expansion. The substrate can be located on the periphery of the fan flow.
2. The convergent flow, oriented to the axis of symmetry is formed behind the nozzle in the shape of closed round axisymmetric slot on the cylindrical surface. At some conditions the shock structure, surrounding the axis of symmetry, is enriched by heavy gas component with temperature essentially higher than stagnation one. This scheme is promising for the deposition of films on the surface of stretched cylindrical bodies (wires, capillaries, fibers).
3. If two sources according to the case 2 are located on one axis, the region of the interaction of two opposite supersonic flows along one axis has extremely high temperature and concentration of heavy component. After collision gas endures the fan expansion like in the case 1.
In the full presentation the structure of flows and the results of analysis of non-equilibrium processes will be presented, including the energy distribution of molecule before deposition.
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