Abstract: A high-quality polycrystalline bulk semiconductor having a large crystal grain size is produced by the casting method in which growth is regulated so as to proceed in the same plane direction, i.e., the {110}; plane or {112} plane is disclosed. The process, which is for producing a polycrystalline bulk semiconductor, comprises: a step in which a melt of a semiconductor selected among Si, Ge, and SiGe is held in a crucible; a step in which a bottom part of the crucible is cooled to give a temperature gradient and that part of the melt which is located directly on the crucible bottom is rapidly cooled in the beginning of growth to supercool the melt around the crucible bottom; a step in which the crucible is cooled to grow nuclei on the crucible bottom due to the supercooled state of the melt around the crucible bottom and thereby grow dendritic crystals along the crucible bottom; and a step in which a polycrystalline bulk of the semiconductor is then grown on the upper side of the dendritic crystals.

Abstract: In one embodiment of the present invention, a curvature distribution crystal lens of the present invention is obtained via press-molding. In the case of a Ge single crystal plate, a temperature for the press-molding is in a range 1° C. to 120° C. lower than a melting point. In the case of a Si single crystal plate, a temperature for the press-molding is in a range 1° C. to 200° C. lower than a melting point. The curvature distribution crystal lens has a crystal lattice plane forming a 1D cylindrically curved surface or a 1D logarithmically curved surface whose valley is in a direction perpendicular to a direction having a maximum curvature, the direction having the maximum curvature being within 30° from a [001] or [1-10] direction in a (110) plane. As a result, it is possible to make an integrated reflection intensity uniform and to make a half-value width uniform in a wide range.

Abstract: In growing a single-crystal silicon by the present invention in a Czochralski method, after a surface of a silicon melt is brought into contact with a seed crystal in a crucible, the silicon melt being added with germanium, the single-crystal silicon is pulled while rotated, and the solar-cell single-crystal silicon substrate is sliced from the single-crystal silicon containing germanium, whereby a germanium content of solar-cell single-crystal silicon substrate is set in the range of not less than 0.03 mole % to less than 1.0 mole % when resistivity ranges from 1.4 to 1.9 ?cm. Therefore, conversion efficiency is enhanced when compared with conventional single-crystal silicon substrates. Accordingly, solar cell power generation costs decreases, so that the single-crystal silicon of the present invention can widely be utilized as the substrate for the solar cell in which the high conversion efficiency is increasingly demanded.

Abstract: In one embodiment of the present invention, a curvature distribution crystal lens of the present invention is obtained via press-molding. In the case of a Ge single crystal plate, a temperature for the press-molding is in a range 1° C. to 120° C. lower than a melting point. In the case of a Si single crystal plate, a temperature for the press-molding is in a range 1° C. to 200° C. lower than a melting point. The curvature distribution crystal lens has a crystal lattice plane forming a 1D cylindrically curved surface or a 1D logarithmically curved surface whose valley is in a direction perpendicular to a direction having a maximum curvature, the direction having the maximum curvature being within 30° from a [001] or [1-10] direction in a (110) plane. As a result, it is possible to make an integrated reflection intensity uniform and to make a half-value width uniform in a wide range.

Abstract: A multi-crystalline silicon germanium bulk crystal with microscopic compositional distribution is adapted for use in solar cells to substantially increase conversion efficiency. By controlling the average Ge concentration between 0.1 and 8.0 mole percent, significant improvements are attained with respect to short circuit current density and conversion efficiency.

Abstract: A high-quality polycrystalline bulk semiconductor having a large crystal grain size is produced by the casting method in which growth is regulated so as to proceed in the same plane direction, i.e., the {110}; plane or {112} plane is disclosed. The process, which is for producing a polycrystalline bulk semiconductor, comprises: a step in which a melt of a semiconductor selected among Si, Ge, and SiGe is held in a crucible; a step in which a bottom part of the crucible is cooled to give a temperature gradient and that part of the melt which is located directly on the crucible bottom is rapidly cooled in the beginning of growth to supercool the melt around the crucible bottom; a step in which the crucible is cooled to grow nuclei on the crucible bottom due to the supercooled state of the melt around the crucible bottom and thereby grow dendritic crystals along the crucible bottom; and a step in which a polycrystalline bulk of the semiconductor is then grown on the upper side of the dendritic crystals.

Abstract: In growing a single-crystal silicon by the present invention in a Czochralski method, after a surface of a silicon melt is brought into contact with a seed crystal in a crucible, the silicon melt being added with germanium, the single-crystal silicon is pulled while rotated, and the solar-cell single-crystal silicon substrate is sliced from the single-crystal silicon containing germanium, whereby a germanium content of solar-cell single-crystal silicon substrate is set in the range of not less than 0.1 mole % and less than 1.0 mole %. Desirably the germanium content is set in the range of not less than 0.1 mole % to not more than 0.6 mole %, and the germanium content is set in the range of not less than 0.03 mole % to less than 1.0 mole % when resistivity ranges from 1.4 to 1.9 ?cm. Therefore, conversion efficiency can largely be enhanced compared with the case where the conventional single-crystal silicon substrate is used.

Abstract: A multi-crystalline silicon germanium bulk crystal with microscopic compositional distribution is adapted for use in solar cells to substantially increase conversion efficiency. By controlling the average Ge concentration between 0.1 and 8.0 mole percent, significant improvements are attained with respect to short circuit current density and conversion efficiency.

Abstract: A Si melt is contacted to a main surface of a Si substrate made of metallurgical Si raw material to conduct liquid phase epitaxy within a temperature range around Si melting point and to form a Si crystal thin film on the main surface of the Si substrate.

Abstract: The present invention provides a multi-element polycrystal having a non-uniform microscopic distribution of the elements, by cooling a melt containing a plurality of elements at a controlled cooling rate. The present invention further provides a polycrystal for use in a solar cell capable of absorbing sunlight more efficiently at low cost, a solar cell using the polycrystal and methods of forming the polycrystal and the solar cell.

Abstract: A slab is successively fed between periodically moving press tools to reduce the slab in a widthwise direction. In this method, the leading and tail end portions of a given length in the slab are reduced at a reduced width wider than that of remaining steady portion.

Abstract: A lanthanide-containing alloy is produced by retaining the melt of this alloy by the use of a container having the inner surface formed of a calcia-based refractory possessing a CaO content of not less than 90% by weight in a non-oxidizing atmosphere.