Abstract:
A furnace for the growth of crystalline semiconductor material has a heater chamber comprising one or more heating devices, a process chamber in which the crystalline semiconductor material is grown when in use and a separator. The separator is positioned between the heater chamber and process chamber such that the material receives heat from the heating devices via the separator. The separator is provided with a number of channels having a predetermined geometry so as to allow the passage of gas through the separator. A gas flow system is arranged to cause the flow of a process gas from the heater chamber to the process chamber through the channels of the separator. Associated methods are also disclosed.
Abstract:
Method for the initial start of reaction when producing silicon tetrachloride by reaction of silicon metal, ferrosilicon, silicon oxide, and/or silicon carbide with chlorine in fluid bed, fixed bed or disappearing bed reactors. The temperature at the start of chlorination (ignition) is at or close to ambient temperature (room temperature), whereby a small amount of an ignition or reaction initiation material such as an alloy and/or compound that readily reacts exothermally with chlorine at or close to ambient temperature thereby raising the temperature of the adjacent silicon or silicon containing material to a temperature above the chlorination ignition temperature of silicon or the silicon containing material.
Abstract:
A process for casting a magnesium alloy consisting of 2,0 - 6,00 % by weight of aluminium, 3,00 - 8,00 % by weight of rare earth metals (RE-metals), the ratio of the amount of RE-metals to the amount of aluminium expressed as % by weight being larger than 0,8, at least 40 % by weight of the RE-metals being cerium, less than 0,5 % by weight of manganese, less than 1,00 % by weight of zinc, less than 0,01 % by weight of calcium less than 0,01 % by weight of strontium and the balance being magnesium and unavoidable impurities, the total impurity level being below 0,1 % by weight, wherein the alloy is cast in a die the temperature of which is controlled in the range of 180-340°C, the die is filled in a time which expressed in milliseconds is equal to the product of a number between 5 and 500 multiplied by the average part thickness expressed in millimeter, the static metal pressures being maintained during casting between 20-70 MPa and is subsequently intensified up to 180 MPa.
Abstract:
A multi-ingot furnace for the growth of crystalline semiconductor material has one or more heating devices for heating a hot zone in which crucibles containing semiconductor material are received. At least one of the heating devices is arranged to apply a predetermined differential heat flux profile across a horizontal cross-section of the semiconductor material in one or more of the crucibles, the predetermined differential heat flux profile being selected in dependence the position of the one or more crucibles in an array. In this manner, the heating device can at least partially compensate for differences in the temperature across the semiconductor material that arises from its geometric position in the furnace. This reduces the possibility of defects such as dislocations during the growth of a crystalline semiconductor material. Associated methods are also disclosed.
Abstract:
A process and equipment for reacting silicon tetrachloride with liquid zinc to produce silicon and zinc chloride the reaction taking place in a reactor (1 ). Silicon tetrachloride gas is injected continuously through one or more nozzles (7) into a flow of molten zinc (5) in a reaction zone (2) of the reactor where the temperature is above the melting temperature of zinc (>419°C) and below the boiling temperature of zinc chloride at 1 atmosphere pressure (732°C). The reaction products, silicon and zinc chloride are collected in a separation zone (3) from which they may be removed. Silicon with high purity is effectively and cheaply produced by the present inventive process and equipment.
Abstract:
Salt composition for protecting, refining and/or recycling molten magnesium or magnesium alloys, whereby the salt composition consists of halogenides of strontium, potassium, cesium or mixtures thereof.
Abstract:
salt composition for protecting, refiniag and/or recycling molten magnesium or magnesium alloys, whereby the salt composition consists of halogenides of strontium, potassium, cesium or mixtures thereof .
Abstract:
A magnesium alloy consisting of 1,00 - 10,00 % by weight of aluminium, 1,00 - 8,00 % by weight of rare earth metals (RE-metals), at least 40 % by weight of the RE-metals being cerium, less than 0,5 % by weight of manganese, less than 1,00 % by weight of zinc, 0,00 - 3,00 % by weight of calcium, 0,00 - 3,00 % by weight of strontium and the balance being magnesium and unavoidable impurities, the total impurity level being below 0,1 % by weight.
Abstract:
A process for the re-use of remainders or other residual Si of high purity silicon such as saw dust or kerf from manufacturing of solar cells wafers or semi-contductor devices, is characterized in that the dry kerf, chips and/or other residual Si from wafer production processes or semi-conductor devices is used as feedstock together with metallurgical grade silicon in a direct chlorination reactor (1) producing silicon tetrachloride, SiCI4. Un- reacted kerf or other small particles that escape the reaction zone unreacted are repeatedly returned to the reactor for further chlorination regardless of their size. The equipment included in the process may, beyond the reactor (1), comprise a storage and mixing device (2) for the mixing and storage of the Si material/kerf, a recovery device (3) for separation and recovery of Si containing particles escaping the reaction zone of the reactor and being returned to the reaction zone of the reactor by a return feeding means (9), a condensation unit (10) in which the smallest sized particles escaping the reaction zone of the reactor and recovery device are collected in a slurry with the liquid SiCI4, and a mixing unit (13) into which additional kerf, chips and other residual Si from wafer production processes or semi-conductor devices is added and mixed with the existing SiCI 4 /Si slurry that is subsequently added directly to the reaction zone of the reactor for cooling and temperature control.
Abstract:
Process for producing silicon tetrachloride, SiCI 4 by reaction of silicon metal, Si and chlorine, Cl 2 in a reactor. The temperature and rate of reaction is controlled by simultaneous, direct injection of chlorine and a cooling medium to the reaction zone of the reactor where the cooling medium is introduced as a liquid at a temperature lower than the reactor temperature and evaporates inside the reactor utilizing its heat of evaporation and its specific heat capacity for cooling. The cooling medium may preferably be silicon tetrachloride or an inert gas.