Abstract: A method is provided for converting polycrystalline ribbon to macrocrystalline ribbon in which a molten zone is formed in and moved along the polycrystalline ribbon. Macrocrystalline material in ribbon shape is formed as the molten region passes and the molten material resolidifies. The molten zone is formed in the polycrystalline ribbon by impinging energy beams from two energy sources on the two major surfaces of the ribbon. The combined energy from the first and second energy sources is sufficient to melt the ribbon material and to form a molten zone extending through the thickness of the ribbon. The molten zone has an intersection with each of the major surfaces of the ribbon. The two energy sources are adjusted independently to control the area of the intersection of the molten zone with each surface so that the areas are non-identical.

Abstract: Polycrystalline silicon is produced by a high pressure plasma process. A silicon halide or halosilane is reacted with hydrogen in the presence of a high pressure plasma to deposit silicon on a heated substrate. The effluent from this reaction is collected, the silicon-bearing compounds separated out, and re-introduced to the deposition reaction. The initial silicon bearing compound can be inexpensive silicon tetrachloride. Maximum utilization of all silicon bearing reaction products maximizes polycrystalline silicon production efficiency.

Abstract: Polycrystalline silicon is deposited on the interior surface of a shaped container. The silicon is deposited by reacting hydrogen and a silicon bearing gas in the presence of a high pressure plasma. The silicon body is separated from the shaped container by utilizing thermal expansion shear stress.

Abstract: A method of producing monocrystalline semiconductor material in web form which provides the steps of providing a web of polycrystalline semiconductor material having a width which is much greater than its thickness, providing a monocrystalline semiconductor material seed having the same relative dimensions as the polycrystalline material source, providing one or more semiconductor material shaping members, contacting the source, the seed and the shaping member and heating the interface therebetween preferentially to produce a molten zone, moving said monocrystalline semiconductor material seed away from said molten zone as monocrystalline semiconductor material is formed thereon.