US Patent 7816153 Method and apparatus for producing a dislocation-free crystalline sheet

A dislocation-free sheet may be formed from a melt. A sheet of material with a first width is formed on a melt of the material using a cooling plate. This sheet has dislocations. The sheet is transported with respect to the cooling plate and the dislocations migrate to an edge of the sheet. The first width of the sheet is increased to a second width by the cooling plate. The sheet does not have dislocations at the second width. The cooling plate may have a shape with two different widths in one instance. The cooling plate may have segments that operate at different temperatures to increase the width of the sheet in another instance. The sheet may be pulled or flowed with respect to the cooling plate.