Apparatus and method for producing polycrystalline ribbon

摘要

A method for the substantially continuous growth of polycrystalline silicon ribbon. The polycrystalline silicon is chemically vapor deposited on elongated foils which move slowly through a resistance heated furnace chamber. Vapor sealing entrance and exit ports are provided which allow the continuous transfer of the foils and polycrystalline ribbon between the chamber and the ambient. The foils are positioned within the chamber so as to mask the chamber walls and to restrict the deposition to the foils. All deposition of polycrystalline silicon takes place on one side of each of the foil pieces; deposition on the edges or backs of the foils is prevented by the positioning of the foils relative to each other. Adhesion of the foils to each other is prevented by insuring that all foils are in relative motion. The process is highly efficient and cost effective because it employs efficient resistance heating, because the only surfaces which the reactant gases can contact are hot and are regions of desired deposition, and because the length of the reaction zone can be made long enough to obtain an optimum amount of gas reaction.