Abstract: The present invention consists in obtaining, with the capsule described, a vertical gradient favorable for diamond growth that prevails over any radial gradient by means of heating discs placed at the ends of the heating area, which implies a considerable control over the growth conditions. More specifically, in regard to the rate of growth, it allows for a better control of the quality of large crystals. Another important novelty is to use a source of carbon with a special design formed by cylindrical and conical hollows (graphite, amorphous carbon, diamond or other) with a solvent metal with a number of gases that are introduced in the capsule. Also, a nitrogen scavenger is used to avoid the formation of nitrides, carbides and oxides that are harmful for the growth and that as a significant novelty is placed outside the reaction area.

Abstract: A method for producing a silicon carbide single crystal, which comprises bringing a silicon carbide single crystal substrate into contact with a melt prepared by melting a raw material containing Si and C, and growing a silicon carbide single crystal on the substrate, the method including performing a cycle comprising the following steps (a) and (b): a) a step of bringing the seed crystal substrate into contact with the surface of the melt, growing a single crystal, and separating the seed crystal substrate from the surface of the melt thereby interrupting the growth of the single crystal, and b) a step of bringing the seed crystal substrate into contact with the surface of the melt and growing a single crystal, at least one time, wherein the seed crystal is a 6H-silicon carbide single crystal or a 15R-silicon carbide single crystal and the resulting single crystal is a 4H-silicon carbide single crystal.

Abstract: Processes and machines for producing large area sheets or films of crystalline, polycrystalline, or amorphous material are set forth; the production of such sheets being valuable for the manufacturing of solar photovoltaic cells, flat panel displays and the like. The surface of rotating cylindrical workpiece (10) is implanted with ion beam (30), whereby a layer of weakened material is formed below the surface. Sheet (20) is detached and peeled off, producing arbitrarily large, monolithic sheets. The sheet may be supported on a temporary or permanent handle (50) such as a glass sheet or a polymer film. Pinch roller (60) may assist in the lamination of handle (50) to sheet (20) before or after the point of separation of sheet (20) from workpiece (10). The implantation, annealing and separation processes are adapted to encourage the material to separate along the implanted layer rather than a particular crystal plane.