| 摘要 |
Silicon is deposited from a mixture of hydrogen and a halosilane, e.g. trichlorosilane, on to one or more, preferably two, heated silicon filaments arranged in a cylindrical reaction chamber parallel to the axis thereof and downstream of the point of injection of the reactant gas mixture, the injection orifice having a diameter of less than 0.1 inch., preferably less than 0.05 inch, and the gas mixture being injected parallel to the filaments at a rate of more than 5 1./min. and at a velocity of more than 200 m./sec. preferably <PICT:0875622/III/1> <PICT:0875622/III/2> <PICT:0875622/III/3> more than 500 m./sec. The filaments are preferably 12 inches, more preferably 18 inches long. Two filaments may be spaced at least 1.5 inches apart, each filament being at least 1 inch from the nearest wall of the reaction chamber. The reaction chamber may have a diameter of 22-33% of the length of the filaments. The line from the injection orifice to the upstream end of each filament and the plane through the orifice normal to the axis of each filament may intersect at an angle of 20-30 degrees (Figs. 1 and 2). In a modification (Fig. 3), two injection orifices may be used to produce a single turbulent stream. Hydrogen and trichlorosilane may be reacted in a mol. ratio of 6-30 to 1, preferably 6-20 to 1. The filaments may be raised to a temperature of 1150 DEG C. by resistance heating. |
