Abstract: A method and a device for igniting silicon rods outside a CVD-reactor. A silicon rod is disposed inside a chamber of a casing of an ignition device. At least one pair of contact electrodes applies a first voltage supplied by a transformer with an open circuit voltage sufficiently high to initialize a current flow in and ignite the silicon rod. Optionally, the silicon rod may be heated by a current flow and/or an external heating unit to a temperature within a predetermined range. The silicon rod is removed from the ignition device and may be exposed to a depositing process inside a CVD-reactor. The ignition of the silicon rod outside the CVD-reactor facilitates a new ignition for the depositing process.

Abstract: An apparatus and method for applying a voltage across silicon rods in a CVD reactor has a series connection wherein the silicon rods may be inserted as resistors. A first power supply unit has first transformers connected with one silicon rod. A second power supply unit has second transformers connected to the same number of silicon rods as the first transformers in parallel to one or more of the first transformers. The second transformers have an open circuit voltage lower than the first transformers and a short circuit current higher than the first transformers. A third power supply unit has outputs connected with the silicon rods in parallel to the first and second transformers. The third power supply unit is capable of providing a current in a voltage range below the open circuit voltage of the second transformer and higher than the short circuit current of the second transformer.

Abstract: A process and apparatus for producing polycrystalline silicon ingots. A crucible is arranged in a process chamber and filled with solid silicon material. At least one diagonal heater is located laterally offset to and generally above the silicon ingot to be produced. The silicon material is heated to form molten silicon in the crucible, and thereafter cooled down below the solidification temperature of the molten silicon. A temperature profile in the silicon material during the cooling phase is controlled at least partially via the at least one diagonal heater. The apparatus includes a process chamber, a crucible holder, and at least one diagonal heater. The diagonal heater is located laterally with respect to the crucible holder and generally above a polycrystalline silicon ingot to be formed in the crucible. The diagonal heater is stationary with respect to the crucible holder when the process chamber is closed.

Abstract: A crucible is filled with silicon material and is arranged in a process chamber. The silicon material in the crucible is melted and is subsequently cooled below the solidification temperature. During a time period, a plate element that has at least one passage may be arranged over the molten silicon in the crucible, and a gas flow may be directed onto the surface of the molten silicon at least partially via the at least one passage. Alternatively a crucible arrangement includes a crucible and a holding ring arranged on or above a crucible filled with silicon material. Additional silicon material may be received and held above the crucible by the holding ring. During the heating of the silicon material in the crucible and the holding ring, molten silicon is formed in a crucible, which is subsequently cooled below the solidification temperature of the silicon.

Abstract: A method and a device for igniting silicon rods outside a CVD-reactor. A silicon rod is disposed inside a chamber of a casing of an ignition device. At least one pair of contact electrodes applies a first voltage supplied by a transformer with an open circuit voltage sufficiently high to initialize a current flow in and ignite the silicon rod. Optionally, the silicon rod may be heated by a current flow and/or an external heating unit to a temperature within a predetermined range. The silicon rod is removed from the ignition device and may be exposed to a depositing process inside a CVD-reactor. The ignition of the silicon rod outside the CVD-reactor facilitates a new ignition for the depositing process.

Abstract: A process for melting silicon, in which silicon bodies (4; 14; 24) are detached from a silicon starting material (2) - (40) -, the silicon bodies (4; 14; 24) being dimensioned - (40) - in such a way that they can be arranged in a heatable crucible (6), the silicone bodies (4; 14; 24) are arranged in the crucible (6) and the crucible (6) is heated - (46) -, at least some of the cavities (10) that occur between the crucible walls (7) and the silicon bodies (4; 14; 24) or between monolithic parts of the silicon bodies (4; 14; 24) when the silicon bodies (4; 14; 24) are arranged in the crucible (6) - (42) - being at least partially filled with silicon granules (8; 18, 20; 28) - (44) -, and an arrangement for melting silicon.

Abstract: An arrangement for measurement of temperature and thickness growth of silicon rods in a silicon deposition reactor employs a temperature measurement device located outside the reactor. Continuous temperature measurement and measurement of the thickness growth throughout the entire deposition process is achieved with a contactlessly operating temperature measurement device arranged outside the silicon deposition reactor in front of a viewing window. The temperature measurement device can be pivoted horizontally about a rotation axis by a rotating drive. The pivoting axis runs parallel to a longitudinal axis of the silicon rod, and the central axis of the temperature measurement device runs through the pivoting axis.

Abstract: A method and arrangement for phase-fired control is provided, in which all controllable electric switching elements are linked by a common controller that has a first input for a first control signal. A set point value is pre-defined as a first input variable and assigned to a device for controlling the controllable electric switching elements. Current flowing through each switching element is measured and transmitted to the device for controlling the switching elements as a respective second input variable. The current value of the voltage in the load is measured and transmitted to the device for controlling the switching elements as a third input variable. The device for controlling the switching elements controls all switching elements in a targeted manner by use of the first, second and third input variables. A maximum of two switching elements are active at any one time.

Abstract: In a process for the hydrogenation of chlorosilanes, a gas mixture of a chlorosilane gas to be hydrogenated and hydrogen gas is heated in a reactor to temperatures in the range between 500° C. and 1800° C. The chlorosilane gas is thereby at least partially hydrogenated. The reactor is heated by way of at least one flame from a fire box surrounding the reactor for the purpose of heating the gas mixture.

Abstract: A method for providing liquid silicon comprising the method steps of filling (10) at least one crucible (50; 50a, 50b, 50c, 50d) with solid silicon (52), melting (12) the solid silicon (52) situated in the at least one crucible (50; 50a, 50b, 50c, 50d), and feeding (14; 24) liquid silicon (58) to the silicon (54) situated in the at least one crucible (50; 50a, 50b, 50c, 50d), and a device for carrying out the method.

Abstract: A process for melting silicon, in which silicon bodies (4; 14; 24) are detached from a silicon starting material (2) - (40) -, the silicon bodies (4; 14; 24) being dimensioned - (40) - in such a way that they can be arranged in a heatable crucible (6), the silicone bodies (4; 14; 24) are arranged in the crucible (6) and the crucible (6) is heated - (46) -, at least some of the cavities (10) that occur between the crucible walls (7) and the silicon bodies (4; 14; 24) or between monolithic parts of the silicon bodies (4; 14; 24) when the silicon bodies (4; 14; 24) are arranged in the crucible (6) - (42) - being at least partially filled with silicon granules (8; 18, 20; 28) - (44) -, and an arrangement for melting silicon.