Patent ID: 7771643

Claim:
A method of making an unsupported article of a semiconducting material, comprising: providing a mold at a temperature T 0 ; providing a molten semiconducting material at a bulk temperature T Melt , wherein T Melt ≧T 0 ; immersing the mold in the molten semiconducting material at least once for a first period of time sufficient to form a solid layer of the semiconducting material over an external surface of the mold and for the formed solid layer of semiconducting material to completely remelt; withdrawing the mold from the molten semiconducting material; holding the mold above the molten semiconducting material for a period of time sufficient to undercool the mold a predetermined amount; immersing the mold in the molten semiconducting material for a second period of time sufficient to form a solid layer of the semiconducting material over the external surface of the mold; withdrawing the mold with the solid layer of semiconducting material on the external surface of the mold; and separating the solid layer of semiconducting material from the mold to form the unsupported article of the semiconducting material.