Abstract: A device for heat treating (annealing) a III-V semiconductor wafer comprises at least one wafer support unit which is dimensioned such that a cover provided above the wafer surface is either spaced without any distance or with a distance of maximally about 2 mm to the wafer surface. A process for heat treating III-V semiconductor wafers having diameters larger than 100 mm and a dislocation density below 1×104 cm?2 is carried out in the device of the invention. SI GaAs wafers produced have an at least 25% increased characteristic fracture strength (Weibull distribution), an improved radial macroscopic and mesoscopic homogeneity and an improved quality of the mechano-chemically polished surface. The characteristic fracture strength is higher than 1900 MPa.

Abstract: A process and a device for producing crystalline silicon, particularly poly- or multi-crystalline silicon are described, wherein a melt of a silicon starting material is formed and the silicon melt is subsequently solidified in a directed orientation. A phase or a material is provided in gaseous, fluid or solid form above the melt in such a manner, that a concentration of a foreign atom selected from oxygen, carbon and nitrogen in the silicon melt and thus in the solidified crystalline silicon is controllable, and/or that a partial pressure of a gaseous component in a gas phase above the silicon melt is adjustable and/or controllable, the gaseous component being selected from oxygen gas, carbon gas and nitrogen gas and gaseous species containing at least one element selected from oxygen, carbon and nitrogen.

Abstract: A single crystal having a technologically generated cleavage surface that extends along a natural crystallographic cleavage plane with an accuracy of less than |0.001°| when measured over a length relevant for the technology of the single crystal or over each of a plurality of surface areas extending in the direction of separation and having a length ?2 mm within the technologically relevant surface area.

Abstract: A method of dividing single crystals, particularly of plates of parts thereof, is proposed, which can comprise: pre-adjusting the crystallographic cleavage plane (2?) relative to the cleavage device, setting a tensional intensity (K) by means of tensional fields (3?, 4?), determining an energy release rate G(?) in dependence from a possible deflection angle (?) from the cleavage plane (2?) upon crack propagation, controlling the tensional fields (3?, 4?) such that the crack further propagates in the single crystal, wherein G(0)?2?e(0) and simultaneously at least one of the following conditions is satisfied: ? ? G ? ? ? ? = 0 ? 2 ? ? e h ? ? if ? ? ? 2 ? G ? ? 2 ? 0 ? ? or ( 2.1 ) ? ? G ? ? ? ? 2 ? ? e h ? ? ? ? : ? ? 1 < ? < ? 2 . ( 2.

Abstract: An embodiment of the invention provides a single crystal cleaved from a larger crystal and having a cleavage surface that extends along a natural crystallographic plane of the single crystal, the cleavage surface produced by generating a stress field to propagate a crack in the larger crystal along the natural plane, so that during cracking by the stress field a magnitude of a derivative of an energy release rate, G(?), generated by the stress field at a front of the crack as a function of angular deviation, ?, from the natural plane, is less than or equal to twice an effective step energy, ?e, divided by a step height, h.

Abstract: A device for heat treating (annealing) a III-V semiconductor wafer comprises at least one wafer support unit which is dimensioned such that a cover provided above the wafer surface is either spaced without any distance or with a distance of maximally about 2 mm to the wafer surface. A process for heat treating III-V semiconductor wafers having diameters larger than 100 mm and a dislocation density below 1×104 cm?2 is carried out in the device of the invention. SI GaAs wafers produced have an at least 25% increased characteristic fracture strength (Weibull distribution), an improved radial macroscopic and mesoscopic homogeneity and an improved quality of the mechano-chemically polished surface. The characteristic fracture strength is higher than 1900 MPa.

Abstract: A process and a device for producing crystalline silicon, particularly poly- or multi-crystalline silicon are described, wherein a melt of a silicon starting material is formed and the silicon melt is subsequently solidified in a directed orientation. A phase or a material is provided in gaseous, fluid or solid form above the melt in such a manner, that a concentration of a foreign atom selected from oxygen, carbon and nitrogen in the silicon melt and thus in the solidified crystalline silicon is controllable, and/or that a partial pressure of a gaseous component in a gas phase above the silicon melt is adjustable and/or controllable, the gaseous component being selected from oxygen gas, carbon gas and nitrogen gas and gaseous species containing at least one element selected from oxygen, carbon and nitrogen.

Abstract: A method of dividing single crystals, particularly of plates of parts thereof, is proposed, which can comprise: pre-adjusting the crystallographic cleavage plane (2?) relative to the cleavage device, setting a tensional intensity (K) by means of tensional fields (3?, 4?), determining an energy release rate G(?) in dependence from a possible deflection angle (?) from the cleavage plane (2?) upon crack propagation, controlling the tensional fields (3?, 4?) such that the crack further propagates in the single crystal, wherein G(0)?2?e(0) and simultaneously at least one of the following conditions is satisfied: ? ? G ? ? ? ? = 0 ? 2 ? ? e h ? ? if ? ? ? 2 ? G ? ? 2 ? 0 ? ? or ( 2.1 ) ? ? G ? ? ? ? 2 ? ? e h ? ? ? ? : ? ? 1 < ? < ? 2 , ( 2.

Abstract: A device for heat treating (annealing) a III-V semiconductor wafer comprises at least one wafer support unit which is dimensioned such that a cover provided above the wafer surface is either spaced without any distance or with a distance of maximally about 2 mm to the wafer surface. A process for heat treating III-V semiconductor wafers having diameters larger than 100 mm and a dislocation density below 1×104 cm?2 is carried out in the device of the invention. SI GaAs wafers produced have an at least 25% increased characteristic fracture strength (Weibull distribution), an improved radial macroscopic and mesoscopic homogeneity and an improved quality of the mechano-chemically polished surface. The characteristic fracture strength is higher than 1900 MPa.

Abstract: A device for heat treating (annealing) a III-V semiconductor wafer comprises at least one wafer support unit which is dimensioned such that a cover provided above the wafer surface is either spaced without any distance or with a distance of maximally about 2 mm to the wafer surface. A process for heat treating III-V semiconductor wafers having diameters larger than 100 mm and a dislocation density below 1×104 cm?2 is carried out in the device of the invention. SI GaAs wafers produced have an at least 25% increased characteristic fracture strength (Weibull distribution), an improved radial macroscopic and mesoscopic homogeneity and an improved quality of the mechano-chemically polished surface. The characteristic fracture strength is higher than 1900 MPa.