Yield of products of increased purity from a fluidized bed reactor where silicon is produced or consumed is enhanced by purging with inert gas, purging with hydrogen gas, and purging with a chlorosilane-containing gas. The purging with hydrogen is conducted at an elevated temperature.

Yield of products of increased purity from a fluidized bed reactor where silicon is produced or consumed is enhanced by purging with inert gas, purging with hydrogen gas, and purging with a chlorosilane-containing gas. The purging with hydrogen is conducted at an elevated temperature.

An anode active material for lithium ion batteries includes one or more unaggregated silicon particles having a mass-based chlorine content of from 5 to 200 ppm and a volume-weighted particle size distribution having diameter percentiles d.sub.50 of from 0.5 ?m to 10.0 ?m.

An anode active material for lithium ion batteries includes one or more unaggregated silicon particles having a mass-based chlorine content of from 5 to 200 ppm and a volume-weighted particle size distribution having diameter percentiles d.sub.50 of from 0.5 ?m to 10.0 ?m.

Provided is a method which not only prevents (i) accumulation of fine silicon powder in a separation device and a pipe which are provided in steps after passage of a filter and (ii) damage to a pump, but also reduces adhesion of a silane oligomer to the filter. A method, in accordance with an embodiment of the present invention, for producing polycrystalline silicon, includes: a silicon deposition step; a separation step; and a fine powder removal step of removing the fine silicon powder by passing a chlorosilane condensate through a filter.

Provided is a method which not only prevents (i) accumulation of fine silicon powder in a separation device and a pipe which are provided in steps after passage of a filter and (ii) damage to a pump, but also reduces adhesion of a silane oligomer to the filter. A method, in accordance with an embodiment of the present invention, for producing polycrystalline silicon, includes: a silicon deposition step; a separation step; and a fine powder removal step of removing the fine silicon powder by passing a chlorosilane condensate through a filter.

Provided is a polycrystalline silicon rod suitable as a raw material for production of single-crystalline silicon. A crystal piece (evaluation sample) is collected from a polycrystalline silicon rod grown by a Siemens method, and a polycrystalline silicon rod in which an area ratio of a crystal grain having a particle size of 100 nm or less is 3% or more is sorted out as the raw material for production of single-crystalline silicon. When single-crystalline silicon is grown by an FZ method using the polycrystalline silicon rod as a raw material, the occurrence of dislocation is remarkably suppressed.

The present invention relates to a process for producing of polycrystalline silicon, and the method includes (1) preparing a silicon-containing gas; (2) storing the silicon-containing gas in a storage tank; (3) depositing polycrystalline silicon by injecting the silicon-containing gas stored in the storage tank to a CVD reactor; (4) treating an off-gas emitted in the depositing step; and (5) injecting the gas treated in the treating step to the storage tank.

The present invention relates to a process for producing of polycrystalline silicon, and the method includes (1) preparing a silicon-containing gas; (2) storing the silicon-containing gas in a storage tank; (3) depositing polycrystalline silicon by injecting the silicon-containing gas stored in the storage tank to a CVD reactor; (4) treating an off-gas emitted in the depositing step; and (5) injecting the gas treated in the treating step to the storage tank.

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.