C01B33/03

PROCESS FOR PRODUCING POLYCRYSTALLINE SILICON
20220010434 · 2022-01-13 · ·

Polycrystalline silicon is produced in a chemical vapour deposition reactor, wherein, outside the reactor at at least one position on at least one reactor component, vibrations of the reactor are measured using a measurement device and optionally recorded. The vibrations may be used to identify rod fall over and other events occurring within the reactor.

PROCESS FOR PRODUCING POLYCRYSTALLINE SILICON GRANULATE

Silicon granulate is produced in a fluidized bed reactor having a fluidized bed region fluidized by a gas flow and heated by a heating apparatus. Seed particles and a feed gas including hydrogen and silane and/or halosilane is continuously supplied, and elemental silicon is deposited on the seed particles to form the silicon granulate, which is discharged as a continuous product stream from the reactor. The fluidized bed temperature affects the quality and formation of the product stream, which may be determined as the temperature of an offgas stream from the fluidized bend region. The temperature, as a responding variable may be determined and controlled by means of the mass and energy balance of a defined scheme.

PROCESS FOR PRODUCING POLYCRYSTALLINE SILICON GRANULATE

Silicon granulate is produced in a fluidized bed reactor having a fluidized bed region fluidized by a gas flow and heated by a heating apparatus. Seed particles and a feed gas including hydrogen and silane and/or halosilane is continuously supplied, and elemental silicon is deposited on the seed particles to form the silicon granulate, which is discharged as a continuous product stream from the reactor. The fluidized bed temperature affects the quality and formation of the product stream, which may be determined as the temperature of an offgas stream from the fluidized bend region. The temperature, as a responding variable may be determined and controlled by means of the mass and energy balance of a defined scheme.

Process for producing polycrystalline silicon
11655541 · 2023-05-23 · ·

Polycrystalline silicon is produced in a chemical vapour deposition reactor, wherein, outside the reactor at at least one position on at least one reactor component, vibrations of the reactor are measured using a measurement device and optionally recorded. The vibrations may be used to identify rod fall over and other events occurring within the reactor.

Process for producing polycrystalline silicon
11655541 · 2023-05-23 · ·

Polycrystalline silicon is produced in a chemical vapour deposition reactor, wherein, outside the reactor at at least one position on at least one reactor component, vibrations of the reactor are measured using a measurement device and optionally recorded. The vibrations may be used to identify rod fall over and other events occurring within the reactor.

Process for preparing polycrystalline silicon
11440803 · 2022-09-13 · ·

The invention relates to a method for producing polycrystalline silicon granulate in a fluidized bed reactor. The method comprises a fluidization of silicon seed particles by means of a fluidizing gas in a fluidized bed, which is heated by a heating device, wherein elemental silicon is deposited by pyrolysis on the silicon seed particles by the addition of a reaction gas containing hydrogen and silane and/or halosilane to form the polycrystalline silicon granulate. In a continuous process, waste gas is discharged from the fluidized bed reactor and hydrogen recovered from said waste to gas is again supplied to the fluidized bed reactor as a circulating gas. The circulating gas has a nitrogen content of less than 1000 ppmv. The invention further relates to polycrystalline silicon granulate having a nitrogen content of less than 2 ppba.

Process for preparing polycrystalline silicon
11440803 · 2022-09-13 · ·

The invention relates to a method for producing polycrystalline silicon granulate in a fluidized bed reactor. The method comprises a fluidization of silicon seed particles by means of a fluidizing gas in a fluidized bed, which is heated by a heating device, wherein elemental silicon is deposited by pyrolysis on the silicon seed particles by the addition of a reaction gas containing hydrogen and silane and/or halosilane to form the polycrystalline silicon granulate. In a continuous process, waste gas is discharged from the fluidized bed reactor and hydrogen recovered from said waste to gas is again supplied to the fluidized bed reactor as a circulating gas. The circulating gas has a nitrogen content of less than 1000 ppmv. The invention further relates to polycrystalline silicon granulate having a nitrogen content of less than 2 ppba.

Controlled Hydrolysis of Hazardous Silicon Polymer Residue

A polymer handling method for a polycrystalline silicon manufacturing device, wherein the polymer byproducts are treated in a manner that the silicon polymers are hydrolyzed. The method creates a heated treatment gas with a moisture content that both treats the polymer to a depth of about 0.25 mm to prohibit formation of the friction and shock sensitive layer near the polymer surface and keeps the hydrolyzed polymer humidified. Furthermore the polymer handling method includes inactivation of the polymer, removal of the polymer of the system and disposal of the polymer after removal.

Controlled Hydrolysis of Hazardous Silicon Polymer Residue

A polymer handling method for a polycrystalline silicon manufacturing device, wherein the polymer byproducts are treated in a manner that the silicon polymers are hydrolyzed. The method creates a heated treatment gas with a moisture content that both treats the polymer to a depth of about 0.25 mm to prohibit formation of the friction and shock sensitive layer near the polymer surface and keeps the hydrolyzed polymer humidified. Furthermore the polymer handling method includes inactivation of the polymer, removal of the polymer of the system and disposal of the polymer after removal.

Silicon Fine Particles and Method for Producing the Same

Provided are silicon fine particles that are effectively prevented from being oxidized and have a crystallite diameter close to that of an amorphous substance. The silicon fine particles of the present invention have an average diameter of primary particles of 30 to 900 nm, a crystallite diameter of less than 10 nm, a chlorine concentration of 1 to 10% by mass, and a ratio (C.sub.o/S) of an oxygen concentration (C.sub.o: % by mass) to a specific surface area (S: m.sup.2/g) of less than 0.05. The method for producing silicon fine particles of the present invention includes: heating a gas containing trichlorosilane to a temperature of 600 to 950° C. in a reactor and thermally decomposing the trichlorosilane to produce a silicon fine particle precursor containing chlorine, then collecting the silicon fine particle precursor, and then heating and dechlorinating the collected silicon fine particle precursor at a temperature of 750 to 900° C. under supply of an inert gas or under reduced pressure.